Zoom lens

Information

  • Patent Application
  • 20030202257
  • Publication Number
    20030202257
  • Date Filed
    May 20, 2003
    21 years ago
  • Date Published
    October 30, 2003
    21 years ago
Abstract
The invention relates to a zoom lens system which is compatible with a TTL optical finder having a diagonal field angle of at least 70° at the wide-angle end and about 7 to 10 magnifications and is fast as represented by an F-number of about 2.8 at the wide-angle end. The zoom lens system comprises a first lens group G1 which is movable along its optical axis during zooming and has positive refracting power, a second lens group G2 which moves toward the image side along the optical axis during zooming from the wide-angle end to the telephoto end and has negative refracting power and rear lens groups G3 to G6 having at least two spacings variable during zooming. In particular, the focal length f1 of the first lens group G1 should meet 6
Description


BACKGROUND OF THE INVENTION

[0001] This application claims benefit of Japanese Patent Application No. 2000-250577 filed in Japan on 8.22.200, the contents of which are incorporated by this reference.



BACKGROUND OF THE INVENTION

[0002] The present invention relates generally to a zoom lens, and more particularly to a high-aperture-ratio, high zoom-ratio zoom lens system including a wide-angle zone which has a phototaking field angle of at least 70° suitable for cameras in general, and video cameras or digital cameras in particular.


[0003] In recent years, attention has been paid on digital cameras (electronic cameras) which are potential next-generation cameras superseding silver-salt 135 mm film (usually called Leica size) cameras. For digital cameras for general users, single-focus lenses having a diagonal field angle of about 60° or zoom lenses of about 3 magnifications using the same at wide-angle ends go mainstream. For high-class users, on the other hand, zoom lenses must be further extended to the wide-angle or telephoto end, and be compatible with TTL optical finders as well. As a matter of course, such zoom lenses are required to have ever higher performance. For zoom lenses having a diagonal field angle of about 75° at the wide-angle end and about 7 to 10 magnifications and compatible with TTL optical finders, some are now commercially available for the aforesaid silver-salt 135 mm film cameras. However, wide-angle, high-zoom-ratio zoom lenses, which are well suitable for image-pickup formats considerably smaller in size than the film camera formats and are fast as expressed by an F-number of about 2.0 to 2.8 at the wide-angle end, are little known except those for TV cameras and other commercial purposes.



SUMAMRY OF THE INVENTION

[0004] The state of the art being like this, an object of the present invention is to provide a wide-angle, high-zoom-ratio zoom lens, and especially a zoom lens system which is compatible with a TTL optical finder having a diagonal field angle of at least 70° at the wide-angle end and about 7 to 10 magnifications, and is fast as well, as expressed by an F-number of about 2.0 to 2.8 at the wide-angle end.


[0005] To achieve this object, the present invention basically provides


[0006] a zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of the zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of the zoom lens system along the optical axis during zooming from a wide-angle end to a telephoto end of the zoom lens system and has negative refracting power, and a rear lens group having at least two movable subgroups or, alternatively,


[0007] a zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of the zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of the zoom lens system along the optical axis during zooming from a wide-angle end to a telephoto end of the zoom lens system and has negative refracting power, and a rear group which is located subsequent to the second lens group and has at least two spacings variable during zooming.


[0008] Such constructions are favorable for achieving high zoom ratios while various aberrations are minimized. The present invention having such basic constructions has the following characteristic features.


[0009] According to the first embodiment of the present invention, there is provided a zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of the zoom lens system during zooming and having positive refracting power, a second lens group which moves toward an image side of the zoom lens system along the optical axis during zooming from a wide-angle end to a telephoto end of the zoom lens system and a rear lens group having at least two spacings variable during zooming, wherein a focal length f1 of the first lens group satisfies the following condition (1):


6<f1/L<20  (1)


[0010] where L is a diagonal length of an effective image pickup surface located in the vicinity of an image-formation plane.


[0011] When the lower limit of 6 to condition (1) is not reached, spherical aberrations remain under-corrected at the telephoto end. When the upper limit to 20 is exceeded, the amount of zooming movement of the movable groups increases, and so the overall size of the zoom lens system tends to increase.


[0012] More preferably, condition (1) should be reduced to


6.5<f1/L<16  (1′)


[0013] Most preferably, condition (1) should be reduced to


7<f1/L<12  (1″)


[0014] According to the second embodiment of the present invention, there is provided a zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of the zoom lens system during zooming and having positive refracting power, a second lens group which moves toward an image side of the zoom lens system along the optical axis during zooming from a wide-angle end to a telephoto end of the zoom lens system and a rear lens group having at least two movable subgroups or a zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of the zoom lens system during zooming and having positive refracting power, a second lens group which moves toward an image side of the zoom lens system along the optical axis during zooming from a wide-angle end to a telephoto end of the zoom lens system and a rear lens group having at least two spacings variable during zooming, wherein a focal length f1 of the first lens group and anomalous dispersion ΔθgF of a medium of at least one positive lens in the first lens group satisfy the following conditions:


6<f1/L<20  (1)


0.015<ΔθgF<0.1  (2)


[0015] where L is a diagonal length of an effective image pickup surface located in the vicinity of an image-formation plane.


[0016] It is here noted that the anomalous dispersion ΔθgF of each medium (vitreous material) is defined by


θgF=AgF+BgF·νd+ΔθgF


[0017] with the proviso that θgF=(ng−nF)/(nF−nC) and νd=(nd−1)/(nF−nC) wherein nd, nF, nC and ng are refractive indices with respect to d-line, F-line, C-line and g-line, respectively, and AgF and BgF are each a linear coefficient determined by two vitreous material types represented by glass code 511605 (available under the trade name of NSL7, Ohara Co., Ltd. with θgF=0.5436 and νd=60.49) and glass code 620363 (available under the trade name of PBM2, Ohara Co., Ltd. with θgF=0.5828 and νd=36.26);that is, AgF is 0.641462485 and BgF is −0.001617829.


[0018] When the lower limit of 0.015 to condition (2) is not reached, short wavelength longitudinal chromatic aberrations remain under-corrected at the telephoto end, and so colors are likely to bleed out at the edges of a subject having a large luminance difference. Any inexpensive medium exceeding the upper limit of 0.1 is little available, and opposite chromatic aberrations occur above 0.1.


[0019] More preferably, conditions (2) and (3) should be reduced to


6.5<f1/L<16  (1′)


0.020<ΔθgF<0.08  (2′)


[0020] Most preferably, conditions (2) and (3) should be reduced to


7<f1/L<12  (1″)


0.025<ΔθgF<0.06  (2″)


[0021] According to the third embodiment of the present invention, there is provided a zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of the zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of the zoom lens system along the optical axis during zooming from a wide-angle end to a telephoto end of the zoom lens system, has negative refracting power and comprises at least three negative lens elements while a positive lens element is located nearest to an image side of the second lens group, or three negative lens elements located nearest to an object side of the second lens group while a positive lens element is located on said image side or a negative lens element while two positive lens elements are located nearest to the image side of the second lens group, with any one of surfaces in the second lens group being defined by an aspheric surface, and a rear lens group having at least two movable subgroups and comprising a total of 6 to 11 lens elements inclusive or a zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of the zoom lens system during zooming, a second lens group which moves toward an image side of the zoom lens system along the optical axis during zooming from a wide-angle end to a telephoto end of the zoom lens system and has negative refracting power and a rear lens group having at least two spacings variable during zooming, wherein the following condition is satisfied with respect to an amount of movement Δz1 of the first lens group from the wide-angle end to the telephoto end when the zoom lens system is focused on an object point at infinity and an amount of movement Δz2 of the second lens group from the wide-angle end to the telephoto end when the zoom lens system is focused on an object point at infinity:


3<(Δz2−Δz1)/L<9  (3)


[0022] where the movement of each lens group toward the image side is assumed to be positive and L is a diagonal length of an effective image pickup surface located in the vicinity of an image-formation plane.


[0023] For zooming from the wide-angle end to the telephoto end, the second lens group is relatively moved away from the first lens group, as already explained. Especially for a high-zoom-ratio zoom lens system, there must be a space large enough for the movement of the second lens group because that amount of movement is large. This is particularly true as the field angle of the zoom lens system becomes wide. As a result, the diameter of the first lens group often becomes too large. When the upper limit of 9 to condition (3) is exceeded, the diameter of the first lens group becomes too large and so the size of the zoom lens system becomes large. When the lower limit of 3 is not reached, there is an increased load of zooming on the rear lens group, which may result in large fluctuations of spherical aberrations upon zooming.


[0024] More preferably, condition (3) should be reduced to


3.2<(Δz2−Δz1)/L<8  (3′)


[0025] Most preferably, condition (3) should be reduced to


3.4<(Δz2−Δz1)/L<7  (3″)


[0026] When a zoom lens system has a wide-angle, high-zoom-ratio arrangement, the largest load is applied on the second lens group. In addition, even the magnitude of the diameter of the first lens group is determined by the power, amount of movement, and arrangement of the second lens group. In consideration of the diameter of the first lens group alone, it is favorable to locate the principal point of the second lens group as close to the object side as possible. Thus, it is preferable that the second lens group is constructed of a front subgroup having negative refracting power and a rear subgroup having positive refracting power. In this case, however, barrel distortion is likely to occur due to the wide-angle, high-zoom-ratio arrangement and difficulty is involved in making correction for astigmatism all over the zooming zone. These problems can substantially be eliminated if the second lens group is constructed of at least three negative lenses and a positive lens located nearest to the image side thereof, or three negative lenses located nearest to the object side thereof and a positive lens located on the image side, or a negative lens and two positive lenses located nearest to the image side thereof, with any one of the surfaces in the second lens group being defined by an aspheric surface.


[0027] When the number of lenses in the rear lens group is less than 6, severe conditions are added to correction of chromatic aberrations and spherical aberrations. When more than 11 lenses are used, on the other hand, the entire rear lens group becomes too thick to secure ample zooming space.


[0028] The rear lens group has a plurality of subgroups. In view of chromatic aberrations, spherical aberrations, coma and increased aperture, it is more preferable to construct the rear lens group of at least two subgroups having positive refracting power, wherein the subgroup located nearest to the image side thereof and having positive refracting power and the subgroup located nearest to the image side thereof and having positive refracting power are each composed of at least three lenses.


[0029] According to the fourth embodiment of the present invention, there is provided a zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of the zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of the zoom lens system along the optical axis during zooming from a wide-angle end to a telephoto end of the zoom lens system, has negative refracting power and comprises at least three negative lens elements while a positive lens element is located nearest to an image side of the second lens group, or three negative lens elements located nearest to an object side of the second lens group while a positive lens element is located on said image side or a negative lens element while two positive lens elements are located nearest to the image side of the second lens group, with any one of surfaces in the second lens group being defined by an aspheric surface, and a rear lens group having at least two movable subgroups and comprising a total of 6 to 11 lens elements inclusive or a zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of the zoom lens system during zooming, a second lens group which moves toward an image side of the zoom lens system along the optical axis during zooming from a wide-angle end to a telephoto end of the zoom lens system and has negative refracting power and a rear lens group having at least two spacings variable during zooming, wherein the following condition is satisfied with respect to an amount of movement Δz1 of the first lens group from the wide-angle end to the telephoto end when the zoom lens system is focused on an object point at infinity and an amount of movement Δz2 of the second lens group from the wide-angle end to the telephoto end when the zoom lens system is focused on an object point at infinity:


−1.0<(Δz1/Δhd z2<0.5 where Δz2>0  (4)


[0030] where the movement of each lens group toward the image side is assumed to be positive.


[0031] This is the condition for making a proper locus of an image point defined by a composite first-and-second lens group system upon zooming from the wide-angle end to the telephoto end. By this locus, the magnification-variable zone and focal length of the rear lens group are determined to some extent. When the upper limit of 0.5 to condition (4) is exceeded, the magnification of the rear lens group becomes low or the focal length of the rear lens group becomes long and, hence, the entire size of the zoom lens system tends to become large relative to the value of L. When the lower limit of −1.0 is not reached, on the contrary, the entire size of the zoom lens system becomes small relative to the value of L. However, when the value of L is small and the F-number is small, it is difficult to make correction for spherical aberrations and comas.


[0032] It is acceptable to meet condition (4) and condition (3) simultaneously.


[0033] More preferably, condition (4) should be reduced to


−0.9<(Δz1z2<0.4 where Δz2>0  (4′)


[0034] Most preferably, condition (4) should be reduced to


−0.8<(Δz1z2<0.3 where Δz2>0  (4″)


[0035] According to the fifth embodiment of the present invention, there is provided a zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system and has negative refracting power, and a rear lens group having at least two movable subgroups or a zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system and has negative refracting power, and a rear lens group having at least two spacings variable during zooming, wherein said first lens group moves toward said image side in a convex reciprocation locus and an amount of movement Δz1WM of said first lens group from said wide-angle end to an intermediate focal length of said zoom lens system, given by fM(={square root}{square root over ( )}(fW·fT)), is positive where fW is a composite focal length of said zoom lens system when focused at said wide-angle end on an object point at infinity and fT is a composite focal length of said zoom lens system when focused at said telephoto end on an object point at infinity, with the proviso that the movement of said first lens group lens toward said image side is assumed to be positive and fM is the geometric mean of fW and fT. It is here noted that upon zooming from the wide-angle end to the telephoto end, the second lens group moves relatively away from the first lens group and the rear lens group moves in such a way that its principal point position goes off an image plane. It is also noted that the position of the image plane is kept constant.


[0036] When an electronic image pickup device or a viewing frame having a small value for L, the magnification of the rear lens group is particularly small or nearly one even at the telephoto end, because the ratio of the focal length of the first lens group to that of the zoom lens system becomes very large. At the same time, since the focal length of the rear lens group is longer than that of the second lens group, it is required that a locus of an image point defined by a composite first-and-second lens group system upon zooming from the wide-angle end to the telephoto end change considerably sharply toward the image side in the vicinity of the wide-angle end, and change considerably gently at the telephoto end. In other words, it is preferable that such a locus as mentioned above is taken by the first lens group.


[0037] According to the sixth embodiment of the present invention, there is a zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system and has negative refracting power, and a rear lens group having at least two movable subgroups or a zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system and has negative refracting power, and a rear lens group having at least two spacings variable during zooming, wherein said first lens group moves toward said image side in a convex reciprocation locus and only the aforesaid condition (4) or both conditions (3) and (4) are satisfied.


[0038] In this embodiment, too, the effects mentioned with reference to the fourth and fifth embodiments are obtainable.


[0039] According to the seventh embodiment of the present invention, there is provided a zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system, has negative refracting power and comprises at least three negative lenses while a positive lens is located nearest to said image side, or three negative lenses located nearest to said object side while a positive lens is located on said image side or a negative lens while two positive lenses are located nearest to said image side, with any one of surfaces in said second lens group being defined by an aspheric surface, and a rear lens group having at least two movable subgroups and comprising a total of 6 to 11 lens elements inclusive, or a zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system and has negative refracting power and a rear lens group having at least two spacings variable during zooming.


[0040] When a zoom lens system has a wide-angle, high-zoom-ratio arrangement, the largest load is applied on the second lens group. In addition, even the magnitude of the diameter of the first lens group is determined by the power, amount of movement, and arrangement of the second lens group. In consideration of the diameter of the first lens group alone, it is favorable to locate the principal point of the second lens group as close to the object side as possible. Thus, it is preferable to locate a positive lens nearest to the image side of the second lens group. In this case, however, barrel distortion is likely to occur due to the wide-angle, high-zoom-ratio arrangement and difficulty is involved in making correction for astigmatism all over the zooming zone. These problems can substantially be eliminated if the second lens group is constructed of at least three negative lenses, wherein at least one surface is formed by an aspheric surface. In particular, it is preferable that the aspheric surface is of such a shape that off and off the center of the aspheric surface, its divergence becomes weaker or its convergence becomes stronger as compared with its longitudinal curvature. Even when the second lens group is constructed of three negative lenses located nearest to the object side thereof with a positive lens located on the image side thereof or constructed of a negative lens with two positive lenses located nearest to the image side thereof, similar effects are obtainable as already mentioned.


[0041] Furthermore in this embodiment, the following conditions should preferably be satisfied with respect to a β2T2W ratio Δβ2 where β2T is the magnification of the second lens group at the telephoto end and β2W is the magnification of the second lens group at the wide-angle end when the zoom lens system is focused on an object point at infinity and the focal length f2 of the second lens group.


0.3<log(Δβ2)/log(γ)<0.8  (5)


5<γ<15  (6)


[0042] Here γ is the zoom ratio of the zoom lens system from the wide-angle end to the telephoto end.


[0043] When a zoom lens system has a wide-angle, high-zoom-ratio arrangement, the largest load is applied on the second lens group, as already mentioned. In addition, even the magnitude of the diameter of the first lens group is determined by the power, amount of movement, and arrangement of the second lens group. It is thus preferable to allocate the zooming function to the rear lens group as much as possible. Condition (5) is provided to define the proportion of the zoom ratio of the second lens group all over the zooming zone. When the upper limit of 0.8 is exceed, the load of the zooming function on the second lens group becomes too large to make correction for the aforesaid off-axis aberrations and reduce the diameter of the first lens group. When the lower limit of 0.3 is not reached, on the contrary, the load of the zooming function on the rear lens group becomes too large and, hence, it is difficult to achieve large aperture because spherical aberrations, coma and so on become instable all over the zooming zone. Condition (6) represents the zoom ratio range wherein condition (5) is effective. Any departure from this range causes condition (5) to be ineffective. In other words, when the upper limit of 15 to condition (6) is exceeded, it is preferable to reduce the degree of allocation of the zooming function to the second lens group to below the lower limit to condition (5). When the lower limit of 5 is not reached, on the other hand, it is acceptable to increase the degree of allocation of the zooming function to the second lens group to greater than the upper limit to condition (5) because influences of aberrations diminish. However, any sufficient zoom ratio is not obtainable.


[0044] More preferably, the aforesaid conditions should be


0.35<log(Δβ2)/log(γ)<0.65  (5′)


9<γ<15  (6′)


[0045] or


0.5<log(Δβ2)/log(γ)<0.8  (5″)


5<γ<9  (6″)


[0046] According to the eighth embodiment of the present invention, there is provided a zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system, has negative refracting power and comprises at least three negative lenses while a positive lens is located nearest to said image side, or three negative lenses located nearest to said object side while a positive lens is located on said image side or a negative lens while two positive lenses are located nearest to said image side, with any one of surfaces in said second lens group being defined by an aspheric surface, and a rear lens group having at least two movable subgroups and comprising a total of 6 to 11 lens elements inclusive, or a zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system and has negative refracting power and a rear lens group having at least two spacings variable during zooming, wherein the following condition is satisfied with respect to the composite magnification βrW of the rear lens group when the zoom lens system is focused at the wide-angle end on an object point at infinity.


−0.6<βrW<−0.1  (7)


[0047] As already mentioned, when an image pickup device or a film viewing frame having a small value for L (the diagonal length of an effective image pickup surface) is used, the ratio of the focal length of the first lens group to that of the zoom lens system becomes very large. For instance, this is because the simple proportional coefficient multiple of an optical system for 135 mm format or APS format cannot be physically applied to mechanical construction or lens machining. For this reason, it is impossible to reduce the focal length of each lens group, and especially the composite focal length of the first and second lens groups. In other words, the magnification of the rear lens group must be smaller than that of an optical system for the aforesaid formats. When the lower limit of −0.6 to condition (7) is not reached, the focal length of the composite first-and-second lens group system tends to become short and, hence, the edge thickness, center thickness and air space of each lens tend to become extremely small. An attempt to secure these make the Petzval sum of the optical system negative and, at the same time, renders it difficult to secure off-axis aberrations such as distortion, astigmatism and coma all over the zooming zone. When the upper limit of −0.1 is exceeded, the lens system tends to become huge.


[0048] It is preferable that the aforesaid rear lens group is composed of at least three subgroups, each having a variable axial relative distance, and three such subgroups have positive, negative, and positive power in order from the object side of the rear lens group.


[0049] Alternatively, it is preferable that the rear lens group is composed of a plurality of subgroups, each having a variable axial relative distance, and all subgroups in the rear lens group have each at least one doublet component. Still alternatively, it is preferable that the rear lens group is composed of at least three subgroups, each having a variable axial relative distance and all subgroups in the rear lens group have each at least one doublet component.


[0050] It is more preferable that when 9<γ<15 (6′), −0.5<βrW<−0.1 (7′), or when 5<γ<9 (6″), −0.6<βrW<−0.2 (7″).


[0051] According to the ninth embodiment of the present invention, there is provided a zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system, has negative refracting power and comprises at least three negative lenses while a positive lens is located nearest to said image side, or three negative lenses located nearest to said object side while a positive lens is located on said image side or a negative lens while two positive lenses are located nearest to said image side, with any one of surfaces in said second lens group being defined by an aspheric surface, and a rear lens group having at least two movable subgroups and comprising a total of 6 to 11 lens elements inclusive, or a zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system and has negative refracting power and a rear lens group having at least two spacings variable during zooming, wherein focusing is effected by any one of subgroups located nearer to an image side of said rear lens group than a positive subgroup of subgroups having negative magnification, said positive subgroup located nearest to an object side of said rear lens group, and the following condition is satisfied with respect to a magnification βRRW of said positive subgroup located nearest to the image side of said rear lens group when said zoom lens system is focused at said wide-angle end on an object point at infinity:


−0.4<βRRW<0.9  (8)


[0052] In the present invention, focusing is effected by moving a subgroup or subgroups in the rear lens group on the optical axis, and zooming is effected by the second lens group and the rear lens group. Actually, however, only the subgroup of a plurality of subgroups constituting the rear lens group, which subgroup has positive refracting power and negative magnification and is located nearest to the object side of the rear lens group, contributes to zooming. Other subgroups are designed to have magnifications far away from −1, so that focusing can be done by one or more of the subgroups. It is particularly preferable to effect focusing with a positive subgroup located nearest to the image side of the rear lens group, because there are little fluctuations of aberrations with focusing. Condition (8) is provided to define the magnification βRRW of the positive subgroup located nearest to the image side of the rear lens group. Falling below the lower limit of −0.4 is not preferable because of increased fluctuations of the paraxial amount and the amount of aberrations. Exceeding the upper limit of 0.9 is again not preferable because the amount of movement of the focusing subgroup becomes too large and so this subgroup tends to interfere with the adjacent subgroup before focusing is achieved from an object point at infinity to a close-up object point.


[0053] It is preferable that focusing is effected by the positive subgroup located nearest to the image side of the rear lens group and/or a negative subgroup located on the object side of the rear lens group, because fluctuations of aberrations with focusing can be so reduced that proper focusing and proper sensitivity can be obtained.


[0054] More preferably, condition (8) should be reduced to


−0.3<βRRW<0.8  (8″)


[0055] Most preferably, condition (8) should be reduced to


−0.2<βRRW<0.7  (8″)


[0056] According to the tenth embodiment of the present invention, there is provided a a zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system, has negative refracting power and comprises at least three negative lenses while a positive lens is located nearest to said image side, or three negative lenses located nearest to said object side while a positive lens is located on said image side or a negative lens while two positive lenses are located nearest to said image side, with any one of surfaces in said second lens group being defined by an aspheric surface, and a rear lens group having at least two movable subgroups and comprising a total of 6 to 11 lens elements inclusive, or a zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system and has negative refracting power and a rear lens group having at least two spacings variable during zooming, wherein the following conditions are satisfied with respect to an amount of movement ΔzRF of a subgroup of said subgroups in said rear lens group, said subgroup having positive refracting power and located nearest to an object side of said rear lens group, from said wide-angle end to said telephoto end when said zoom lens system is focused on an object point at infinity and an amount of movement ΔzRR of a positive subgroup located nearest to an image side of said rear lens group when said zoom lens system is focused on an object point at infinity:


−0.4<ΔzRRzRF<0.8  (9)


0.3<|ΔzRF|/L<4.0  (10)


[0057] where L is a diagonal length of an effective image pickup surface located in the vicinity of an image-formation plane.


[0058] Of the subgroups constituting the rear lens group, the positive subgroup located nearest to the object side of the rear lens group contributes actually to zooming. Consequently, this subgroup moves monotonously toward the object side of the zoom lens system from the wide-angle end to the telephoto end thereof. Other subgroups have magnifications far away from −1, and move or act substantially to make correction for displacements of focusing positions due to zooming and aberrations. On the other hand, as the positive subgroup located nearest to the image side of the rear lens group moves toward the object side of the zoom lens system than required, the position of an exit pupil comes close to the image plane. For this reason, when an electronic image pickup device is used, shading is likely to occur. When the upper limit of 0.8 to condition (9) is exceeded, the exit pupil comes close to the image plane on the telephoto side, and so the angle of light rays incident on the perimeter of a screen becomes too large. When the lower limit of −0.4 is not reached, the total thickness of the rear lens group increases and so the overall size of the optical system becomes large. When the upper limit of 4.0 to condition (10) is exceeded, it is likely that the overall length of the optical system becomes long or fluctuations of aberrations with zooming become noticeable. When the lower limit of 0.3 is not reached, the diameter of the first lens group is likely to become large. These are true even when at least one subgroup is placed midway between the aforesaid two positive subgroups. Especially when that subgroup is a negative one, it is preferable to satisfy


−2<ΔzRN/L<1  (11)


[0059] Here ΔzRN is the amount of movement of the negative subgroup from the wide-angle end to the telephoto end when the zoom lens system is focused on an object point at infinity. When the lower limit of −2 to this condition is not reached, the total thickness of the rear lens group increase and so the overall size of the optical system becomes large. When the upper limit of 1 is exceeded, it is likely that the subgroups interfere during focusing on a nearby object point at the telephoto end. This holds true even when a negative subgroup is located on the object side with respect to the aforesaid positive subgroups and on the image side with respect to the second lens group.


[0060] More preferably, the following conditions should be satisfied independently or simultaneously.


−0.3<ΔzRRzRF<0.7  (9′)


0.5<|ΔzRF|/L<3.5  (10′)


−1.5<ΔzRN/L<0.7  (11′)


[0061] Most preferably, the following conditions should be satisfied independently or simultaneously.


−0.2<ΔzRRzRF<0.6  (9″)


0.7<|ΔzRF/L<3.0  (10″)


−1<ΔzRN/L<0.5  (11″)


[0062] It is also preferable that the positive subgroup located nearest to the object side of the rear lens group has negative magnification in view of its contribution to zooming.


[0063] According to the eleventh embodiment of the present invention, there is provided a zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system, has negative refracting power and comprises at least three negative lenses while a positive lens is located nearest to said image side, or three negative lenses located nearest to said object side while a positive lens is located on said image side or a negative lens while two positive lenses are located nearest to said image side, with any one of surfaces in said second lens group being defined by an aspheric surface, and a rear lens group having at least two movable subgroups and comprising a total of 6 to 11 lenses inclusive, said rear lens group comprising a subgroup having positive refracting power and negative magnification and a positive subgroup located nearest to an image side of said rear lens group which vary in relative positions thereof during zooming, or a zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system and has negative refracting power and a rear lens group having a plurality of subgroups, said rear lens group comprising a subgroup having positive refracting power and negative magnification and a positive subgroup located nearest to an image side of said rear lens group with a negative subgroup located between said two positive subgroup, while said three subgroup vary in relative positions thereof during zooming, wherein said two positive subgroups have each at least one doublet component, at least one aspheric surface and at least one lens formed of a vitreous material with ν>80 where ν is an Abbe constant. Since the chromatic aberrations, spherical aberrations and comas of each lens group are in good condition, satisfactory images can be obtained from the wide-angle end to the telephoto end. It is here preferable that the negative subgroup located midway between the two positive subgroups includes a doublet.


[0064] According to the twelfth embodiment of the present invention, there is provided a zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system, has negative refracting power and comprises at least three negative lenses while a positive lens is located nearest to said image side, or three negative lenses located nearest to said object side while a positive lens is located on said image side or a negative lens while two positive lenses are located nearest to said image side, with any one of surfaces in said second lens group being defined by an aspheric surface, and a rear lens group having at least two movable positive subgroups and comprising a total of 7 to 11 lenses inclusive, or a zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system and has negative refracting power and a rear lens group having at least three spacings variable during zooming, wherein a subgroup located nearest to an object side of said rear lens group has negative refracting power.


[0065] In the zoom lens system according to the present invention, when a finder optical path-splitting member is inserted between the subgroup located nearest to the image side of the rear lens group and the image lance, a long back focus is needed. In other words, an attempt to forcibly ample back focus makes the Petzval sum of the zoom lens system likely to become negative. It is thus preferable that a negative lens subgroup is located nearest to the object side of the rear lens group. It is here noted that the negative subgroup located nearest to the object side of the rear lens group may be made up of one lens component or fixed in the vicinity of a stop. By the “lens component” used herein is intended a lens with no air separation between the object-side surface and the image-side surface thereof, which are in contact with air, or specifically a single lens or a doublet.


[0066] It is preferable that a negative subgroup and an aperture stop are located on the object side with respect to the two positive subgroup and on the image side with respect to the second lens group, with a spacing being at most three times as large as the thickness of that negative subgroup on the optical axis of the zoom lens system.


[0067] When a subgroup having negative refracting power is located nearest to the object side of the rear lens group, it is preferable to construct the rear lens group of seven or more lenses in all.


[0068] In the eleventh embodiment of the invention, it is preferable that the zoom lens system comprises, in order from an object side thereof, a first lens group which is movable along an optical axis thereof during zooming and positive refracting power, a second lens group which is movable along the optical axis and has negative refracting power, and a rear lens group located subsequent thereto and having variable refracting power, while at least one of the following three conditions is satisfied.


2.0<FBW/fW<5.0  (12)


1.4<FW<3.5  (13)


2<ENP/L<5  (14)


[0069] Here FBW is the back focus (calculated on an air basis) when the zoom lens system is focused at the wide-angle end on an object point at infinity, FW is the minimum F-number when the zoom lens system is focused at the wide-angle end on an object point at infinity, and ENP is the position of an entrance pupil at the wide-angle end.


[0070] The present invention is found to be effective for lens systems that satisfy one of these conditions. In particular, the present invention is best suited for image pickup systems using electronic image pickup devices. Especially when the present invention is applied to an image-formation optical system for phototaking systems (cameras, video movies, etc.) including a high-pixel image pickup device with a pixel interval a represented by


1.0×10−4×L<a<6.0×10−4×L (mm)


[0071] it is possible to achieve an image pickup system making effective use of the image quality of a high-pixel arrangement.


[0072] Two or more of the conditions mentioned above with reference to the present zoom lens system should preferably be satisfied simultaneously. More preferably, two or more of the requirements for the present invention should be satisfied at the same time. The more the number of the requirements met, the better the results are.


[0073] In each of the embodiments of the present invention, it is preferable that the second lens group comprises at least three negative lenses while a positive lens is located nearest to said image side, or three negative lenses located nearest to said object side while a positive lens is located on said image side or a negative lens while two positive lenses are located nearest to said image side, with any one of surfaces in said second lens group being defined by an aspheric surface. When the rear lens group has at least two spacings variable during zooming, it is preferable that the rear lens group is made up of 7 to 11 lenses in all. More preferably, the rear lens group is made up of 7 to 9 lenses inclusive in all while two aspheric surfaces are used, because an arrangement favorable in view of size is achievable while high image-formation capability is maintained.


[0074] By the combined use of two or more of the aforesaid embodiments, it is possible to obtain ever higher effects.


[0075] Still other objects and advantages of the invention will be in part be obvious and will in part be apparent from the specification.


[0076] The invention accordingly comprises the features of construction, combinations of elements, and arrangement of parts which will be exemplified in the construction hereinafter set forth, and the scope of the invention will be indicated in the claims.







BRIEF DESCRIPTION OF THE DRAWINGS

[0077]
FIG. 1 is a sectional view for the lens arrangement of Example 1 of the zoom lens system according to the invention when focused on an object point at infinity.


[0078]
FIG. 2 is a sectional view, similar to FIG. 1, of the lens arrangement of Example 2 of the zoom lens system.


[0079]
FIG. 3 is a sectional view, similar to FIG. 1, of the lens arrangement of Example 3 of the zoom lens system.


[0080]
FIG. 4 is a sectional view, similar to FIG. 1, of the lens arrangement of Example 4 of the zoom lens system.


[0081]
FIG. 5 is a sectional view, similar to FIG. 1, of the lens arrangement of Example 5 of the zoom lens system.


[0082]
FIG. 6 is a sectional view, similar to FIG. 1, of the lens arrangement of Example 6 of the zoom lens system.


[0083]
FIG. 7 is a sectional view, similar to FIG. 1, of the lens arrangement of Example 7 of the zoom lens system.


[0084]
FIG. 8 is a sectional view, similar to FIG. 1, of the lens arrangement of Example 8 of the zoom lens system.


[0085]
FIG. 9 is a sectional view, similar to FIG. 1, of the lens arrangement of Example 9 of the zoom lens system.


[0086]
FIG. 10 is a sectional view, similar to FIG. 1, of the lens arrangement of Example 10 of the zoom lens system.


[0087]
FIG. 11 is a sectional view, similar to FIG. 1, of the lens arrangement of Example 11 of the zoom lens system.


[0088]
FIG. 12 is a sectional view, similar to FIG. 1, of the lens arrangement of Example 12 of the zoom lens system.


[0089]
FIG. 13 is a sectional view, similar to FIG. 1, of the lens arrangement of Example 13 of the zoom lens system.


[0090]
FIG. 14 is a sectional view, similar to FIG. 1, of the lens arrangement of Example 14 of the zoom lens system.


[0091]
FIG. 15 is a sectional view, similar to FIG. 1, of the lens arrangement of Example 15 of the zoom lens system.


[0092]
FIG. 16 is a sectional view, similar to FIG. 1, of the lens arrangement of Example 16 of the zoom lens system.


[0093]
FIG. 17 is a sectional view, similar to FIG. 1, of the lens arrangement of Example 17 of the zoom lens system.


[0094]
FIG. 18 is a sectional view, similar to FIG. 1, of the lens arrangement of Example 18 of the zoom lens system.


[0095]
FIG. 19 is a sectional view, similar to FIG. 1, of the lens arrangement of Example 19 of the zoom lens system.


[0096]
FIG. 20 is a sectional view, similar to FIG. 1, of the lens arrangement of Example 20 of the zoom lens system.


[0097]
FIG. 21 is a sectional view, similar to FIG. 1, of the lens arrangement of Example 21 of the zoom lens system.


[0098]
FIG. 22 is a sectional view, similar to FIG. 1, of the lens arrangement of Example 22 of the zoom lens system.


[0099]
FIG. 23 is a sectional view, similar to FIG. 1, of the lens arrangement of Example 23 of the zoom lens system.


[0100]
FIG. 24 is a sectional view, similar to FIG. 1, of the lens arrangement of Example 24 of the zoom lens system.


[0101]
FIG. 25 is a sectional view, similar to FIG. 1, of the lens arrangement of Example 25 of the zoom lens system.


[0102] FIGS. 26(a), 26(b) and 26(c) are aberration diagrams for Example 1 when focused on an object point at infinity.


[0103] FIGS. 27(a), 27(b) and 27(c) are aberration diagrams for Example 2 when focused on an object point at infinity.


[0104] FIGS. 28(a), 28(b) and 28(c) are aberration diagrams for Example 3 when focused on an object point at infinity.


[0105] FIGS. 29(a), 29(b) and 29(c) are aberration diagrams for Example 4 when focused on an object point at infinity.


[0106] FIGS. 30(a), 30(b) and 30(c) are aberration diagrams for Example 5 when focused on an object point at infinity.


[0107] FIGS. 31(a), 31(b) and 31(c) are aberration diagrams for Example 6 when focused on an object point at infinity.


[0108] FIGS. 32(a), 32(b) and 32(c) are aberration diagrams for Example 7 when focused on an object point at infinity.


[0109] FIGS. 33(a), 33(b) and 33(c) are aberration diagrams for Example 8 when focused on an object point at infinity.


[0110] FIGS. 34(a), 34(b) and 34(c) are aberration diagrams for Example 9 when focused on an object point at infinity.


[0111] FIGS. 35(a), 35(b) and 35(c) are aberration diagrams for Example 10 when focused on an object point at infinity.


[0112] FIGS. 36(a), 36(b) and 36(c) are aberration diagrams for Example 11 when focused on an object point at infinity.


[0113] FIGS. 37(a), 37(b) and 37(c) are aberration diagrams for Example 12 when focused on an object point at infinity.


[0114] FIGS. 38(a), 38(b) and 38(c) are aberration diagrams for Example 13 when focused on an object point at infinity.


[0115] FIGS. 39(a), 39(b) and 39(c) are aberration diagrams for Example 14 when focused on an object point at infinity.


[0116] FIGS. 40(a), 40(b) and 40(c) are aberration diagrams for Example 15 when focused on an object point at infinity.


[0117] FIGS. 41(a), 41(b) and 41(c) are aberration diagrams for Example 16 when focused on an object point at infinity.


[0118] FIGS. 42(a), 42(b) and 42(c) are aberration diagrams for Example 17 when focused on an object point at infinity.


[0119] FIGS. 43(a), 43(b) and 43(c) are aberration diagrams for Example 18 when focused on an object point at infinity.


[0120] FIGS. 44(a), 44(b) and 44(c) are aberration diagrams for Example 19 when focused on an object point at infinity.


[0121] FIGS. 45(a), 45(b) and 45(c) are aberration diagrams for Example 20 when focused on an object point at infinity.


[0122] FIGS. 46(a), 46(b) and 46(c) are aberration diagrams for Example 21 when focused on an object point at infinity.


[0123] FIGS. 47(a), 47(b) and 47(c) are aberration diagrams for Example 22 when focused on an object point at infinity.


[0124] FIGS. 48(a), 48(b) and 48(c) are aberration diagrams for Example 23 when focused on an object point at infinity.


[0125] FIGS. 49(a), 49(b) and 49(c) are aberration diagrams for Example 24 when focused on an object point at infinity.


[0126] FIGS. 50(a), 50(b) and 50(c) are aberration diagrams for Example 25 when focused on an object point at infinity.


[0127]
FIG. 51 is illustrative of the diagonal length of an effective image pickup surface for phototaking on an image pickup device.


[0128]
FIG. 52 is illustrative of the diagonal length of an effective image pickup surface for phototaking on a phototaking film.


[0129]
FIG. 53 is a front perspective view illustrative of the outside shape of a digital camera with the inventive zoom lens built therein.


[0130]
FIG. 54 is a rear perspective view of the digital camera.


[0131]
FIG. 55 is a sectional view of the FIG. 53 digital camera.


[0132]
FIG. 56 is a conceptual illustration of a single-lens reflex camera's objective optical system with the inventive zoom lens incorporated therein.


[0133]
FIG. 57 is a front perspective view illustrative of an uncovered personal computer in which the inventive zoom lens is incorporated as an objective optical system.


[0134]
FIG. 58 is a sectional view of a phototaking optical system for a personal computer.


[0135]
FIG. 59 is a sectional view of the FIG. 57 state.


[0136] FIGS. 60(a), 60(b) and 60(c) are a front and a side view of a portable telephone in which the inventive zoom lens is incorporated as an objective optical system and a sectional view of a phototaking optical system therefore.







DESCRITPION OF THE PREFERRED EMBODIMENTS

[0137] Set out below are Examples 1 to 25 of the zoom lens system according to the present invention. FIGS. 1 to 25 are sectional views illustrative of the lens arrangements of these examples when focused on an object point at infinity. Throughout the drawings, the first, second, third, fourth, fifth and sixth lens groups are shown at G1, G2, G3, G4, G5 and G6, respectively. A plane-parallel plate group comprising a finder optical path-splitting prism (a plane-parallel plate), an optical low-pass filter with an infrared cutting coat applied thereon and a cover glass for an electronic image pickup device such as a CCD is shown at P and an image plane at I. The plane-parallel plate group P is fixedly located between the final lens group and the image plane I. In FIGS. 1 to 25, the locus of movement of each lens group from the wide-angle end to the telephoto end is schematically depicted by an arrow. Numerical data on each example will be enumerated below.


[0138] As shown in FIG. 1, the zoom lens system of Example 1 is made up of a first lens group G1 having positive refracting power, a second lens group G2 having negative refracting power, a third lens group G3 having negative refracting power, a fourth lens group G4 having positive refracting power, a fifth lens group G5 having negative refracting power and a sixth lens group G6 having positive refracting power. For zooming from the wide-angle end to the telephoto end when the system is focused on an object point at infinity, the first lens group G1 moves toward the image side of the zoom lens system in a convex reciprocating locus and reaches the telephoto end where it is located nearer to the object side of the zoom lens system than at the location of the wide-angle end, the second lens group G2 moves toward the image side, the third lens group G3 remains fixed with an aperture stop integrated therewith on the image side, the fourth lens group G4 moves toward the object side, the fifth lens group G5 moves toward the image side, and the sixth lens group G6 moves toward the object side in a convex reciprocating locus while the spacing between the fifth lens group G5 and the sixth lens group G6 becomes narrow, and reaches the telephoto end where it is located somewhat nearer to the image side than at the location of the wide-angle end. For focusing on a nearby subject, the sixth lens group G6 is designed to move out toward the object side. More specifically, for focusing at 0.3 m from an infinite object distance at the wide-angle end, on the one hand, the sixth lens group G6 moves toward the object side in such a way that the spacing between the fifth lens group G5 and the sixth lens group G6 changes from 8.26323 mm to 8.10753 mm. For focusing at 1.284 m (with a magnification of 1/20) from an infinite object distance at the telephoto end, on the other hand, the sixth lens group G6 moves toward the object side in such a way that the spacing between the fifth lens group G5 and the sixth lens group G6 changes from 5.08574 mm to 1.45116 mm.


[0139] In Example 1, the first lens group G1 is made up of a negative meniscus lens convex on the object side thereof, a double-convex lens and a positive meniscus lens convex on the object side thereof, the second lens group G2 is made up of a double-concave lens, a double-concave lens with an object-side surface thereof provided with a thin resin layer, thereby making this surface aspheric, and a doublet consisting of a negative meniscus lens convex on the image side thereof and a positive meniscus lens convex on the image side thereof, the third lens group G3 is made up of a negative meniscus lens convex on the image side thereof and a stop, the fourth lens group G4 is made up of a double-convex lens and a doublet consisting of a negative meniscus lens convex on the object side thereof and a double-convex lens, the fifth lens group G5 is made up of a double-concave lens and a positive meniscus lens convex on the object side thereof, and the sixth lens group G6 is made up of a double-convex lens and a doublet consisting of a double-convex lens and a negative meniscus lens convex on the image side thereof. Three aspheric surfaces are used, one for the object-side resin layer surface of the double-concave lens in the second lens group G2, one for the object-side surface of the double-convex lens in the fourth lens group G4 and one for the object-side surface of the double-convex lens in the sixth lens group G6.


[0140] As shown in FIG. 2, the zoom lens system of Example 2 is made up of a first lens group G1 having positive refracting power, a second lens group G2 having negative refracting power, a third lens group G3 having negative refracting power, a fourth lens group G4 having positive refracting power, a fifth lens group G5 having negative refracting power and a sixth lens group G6 having positive refracting power. For zooming from the wide-angle end to the telephoto end when the zoom lens system is focused on an object point at infinity, the first lens group G1 moves toward the image side of the zoom lens system in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the object side of the zoom lens system than at the location of the wide-angle end, the second lens group G2 moves toward the image side, the third lens group G3 remains fixed with an aperture stop integrated therewith on the image side, the fourth lens group G4 moves toward the object side, the fifth lens group G5 moves toward the object side in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the image side than at the location of the wide-angle end, and the sixth lens group G6 moves toward the object side in a convex reciprocation locus while the spacing between the fifth lens group G5 and the sixth lens group G6 becomes narrow and then somewhat wide, and reaches the telephoto end where it is located somewhat nearer to the image side than at the location of the wide-angle end. For focusing on a nearby subject, the sixth lens group G6 is designed to move out toward the object side. More specifically, when the system is focused on a nearby subject at the wide-angle end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 7.7998 mm and when focused on a nearby subject at the telephoto end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 2.2730 mm.


[0141] In Example 2, the first lens group G1 is made up of two lenses, i.e., a negative meniscus lens convex on its object side and a positive meniscus lens convex on its object side, the second lens group G2 is made up of a double-concave lens, a double-concave lens with an image-side surface thereof provided with a thin resin layer, thereby making that surface aspheric and a doublet consisting of a negative meniscus lens convex on its mage side and a positive meniscus lens convex on its image side, the third lens group G3 is made up of a negative meniscus lens convex on its image side and a stop, the fourth lens group G4 is made up of a double-convex lens and a doublet consisting of a negative meniscus lens convex on its object side and a double-convex lens, the fifth lens group G5 is made up of a doublet consisting of a double-concave lens and a positive meniscus lens on its object side, and the sixth lens group G6 is made up of a double-convex lens and a doublet consisting of a positive meniscus lens convex on its image side and a negative meniscus lens convex on its image side. Three aspheric surfaces are used, one for the image-side resin layer surface of the double-concave lens in the second lens group G2, one for the object-side surface of the double-convex lens in the fourth lens group G4 and one for the object-side surface of the double-convex lens in the sixth lens group G6.


[0142] As shown in FIG. 3, the zoom lens system of Example 3 is made up of a first lens group G1 having positive refracting power, a second lens group G2 having negative refracting power, a third lens group G3 having negative refracting power, a fourth lens group G4 having positive refracting power, a fifth lens group G5 having negative refracting power and a sixth lens group G6 having positive refracting power. For zooming from the wide-angle end to the telephoto end where the system is focused on an object point at infinity, the first lens group G1 moves toward the image side of the zoom lens system in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the object side of the zoom lens system than at the location of the wide-angle end, the second lens group G2 moves toward the image side, the third lens group G3 remains fixed with an aperture stop integrated therewith on its image side, the fourth lens group G4 moves toward the object side, the fifth lens group G5 moves toward the object side in a convex reciprocation locus and reaches the telephoto end where it is located somewhat nearer to the image side than at the location of the wide-angle end, and the sixth lens group G6 moves toward the object side in a convex reciprocation locus while the spacing between the fifth lens group G5 and the sixth lens group G6 becomes narrow and then somewhat wide, and reaches the telephoto end where it is located somewhat nearer to the object side than at the location of the wide-angle end. For focusing on a nearby subject, the sixth lens group G6 is designed to move out toward the object side. More specifically, when the system is focused on a nearby subject at the wide-angle end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 7.6726 mm and when focused on a nearby subject at the telephoto end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 3.1112 mm.


[0143] In Example 3, the first lens group G1 is made up of two lenses, i.e., a negative meniscus lens convex on its object side and a positive meniscus lens convex on its object side, the second lens group G2 is made up of a negative meniscus lens convex on its object side, a double-concave lens, a positive meniscus lens convex on its object side with an image-side surface thereof provided with a thin resin layer, thereby making that surface aspheric, and a negative meniscus lens convex on its object side, the third lens group G3 is made up of a negative meniscus lens convex on its object side and a stop, the fourth lens group G4 is made up of a double-convex lens and a doublet consisting of a negative meniscus lens convex on its object side and a double-convex lens, the fifth lens group G5 is made up of a doublet consisting of a double-concave lens and a positive meniscus lens convex on its object side, and the sixth lens group G6 is made up of a double-convex lens and a doublet consisting of a double-convex lens and a negative meniscus lens convex on its image side. Three aspheric surfaces are used, one for the image-side resin layer surface of the positive meniscus lens in the second lens group G2, said lens convex on its object side, one for the object-side surface of the double-convex lens in the fourth lens group G4 and one for the image-side surface of the double-convex lens in the sixth lens group G6.


[0144] As shown in FIG. 4, the zoom lens system of Example 4 is made up of a first lens group G1 having positive refracting power, a second lens group G2 having negative refracting power, a fixed aperture stop, a third lens group G3 having positive refracting power, a fourth lens group G4 having negative refracting power and a fifth lens group G5 having positive refracting. For zooming from the wide-angle end to the telephoto end of the zoom lens system when focused on an object point at infinity, the first lens group G1 moves toward the image side of the zoom lens system in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the object side of the zoom lens system than at the location of the wide-angle end, the second lens group G2 moves toward the image side, the third lens group G3 moves toward the object side, the fourth lens group G4 moves toward the object side in a convex reciprocation locus and reaches the telephoto end where it is located somewhat nearer to the object side than at the location of the wide-angle end, and the fifth lens group G5 moves toward the object side in a convex reciprocation locus while the spacing between the fourth lens group G4 and the fifth lens group G5 becomes wide and then somewhat narrow, and reaches the telephoto end where it is located somewhat nearer to the object side than at the location of the wide-angle end. For focusing on a nearby subject, the fifth lens group G5 is designed to move out toward the object side. More specifically, when the system is focused on a nearby subject at the wide-angle end, the spacing between the fourth lens group G4 and the fifth lens group G5 is set at 3.0843 mm and when focused on a nearby subject at the telephoto end, the spacing between the fourth lens group G4 and the fifth lens group G5 is set at 2.2572 mm.


[0145] In Example 4, the first lens group G1 is made up of two lenses, i.e., a negative meniscus lens convex on its object side and a positive meniscus lens convex on its object side, the second lens group G2 is made up of a negative meniscus lens convex on its object side, a double-concave lens and a doublet consisting of a positive meniscus lens convex on its image side and a double-concave lens and a double-convex lens, the third lens group G3, with the fixed aperture stop located between the second lens group G2 and the third lens group G3, is made up of a double-convex lens and a doublet consisting of a double-convex lens and a negative meniscus lens convex on its image side, the fourth lens group G4 is made up of a doublet consisting of a positive meniscus lens convex on its image side and a double-concave lens, and the fifth lens group G5 is made up of a double-convex lens and a doublet consisting of a double-convex lens and a negative meniscus lens convex on its image side. Three aspheric surfaces are used, one for the object-side surface of the doublet in the second lens group G2, one for the object-side surface of the double-convex lens in the third lens group G3 and one for the object-side surface of the double-convex lens in the fifth lens group G5.


[0146] As shown in FIG. 5, the zoom lens system of Example 5 is made up of a first lens group G1 having positive refracting power, a second lens group G2 having negative refracting power, a fixed aperture stop, a third lens group G3 having positive refracting power, a fourth lens group G4 having negative refracting power and a fifth lens group G5 having positive refracting. For zooming from the wide-angle end to the telephoto end of the zoom lens system when focused on an object point at infinity, the first lens group GI moves toward the image side of the zoom lens system in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the object side of the zoom lens system than at the location of the wide-angle end, the second lens group G2 moves toward the image side, the third lens group G3 moves toward the object side, the fourth lens group G4 moves toward the object side in a convex reciprocation locus and reaches the telephoto end where it is located somewhat nearer to the object side than at the location of the wide-angle end, and the fifth lens group G5 moves toward the object side while the spacing between the fourth lens group G4 and the fifth lens group G5 becomes wide and then somewhat narrow. For focusing on a nearby subject, the fifth lens group G5 is designed to move out toward the object side. More specifically, when the system is focused on a nearby subject at the wide-angle end, the spacing between the fourth lens group G4 and the fifth lens group G5 is set at 4.2063 mm and when focused on a nearby subject at the telephoto end, the spacing between the fourth lens group G4 and the fifth lens group G5 is set at 2.006 mm.


[0147] In Example 5, the first lens group G1 is made up of two lenses, i.e., a negative meniscus lens convex on its object side and a positive meniscus lens convex on its object side, the second lens group G2 is made up of a negative meniscus lens convex on its object side, a double-concave lens, a doublet consisting of a positive meniscus lens convex on its image side and a double-concave lens and a double-convex lens. The third lens group G3, with the fixed stop located between the second lens group G2 and the third lens group G3, is made up of a double-convex lens and a negative meniscus lens convex on its image side, the fourth lens group G4 is made up of a doublet consisting of a positive meniscus lens convex on its image side and a double-concave lens, and the fifth lens group G5 is made up of a doublet consisting of a negative meniscus lens convex on its object side and a positive meniscus lens convex on its object side, a double convex lens and a positive meniscus lens convex on its object side. Three aspheric surfaces are used, one for the object-side surface of the doublet in the second lens group G2, one for the object-side surface of the double-convex lens in the third lens group G3 and one for the image-side surface of the double-convex lens in the fifth lens group G5.


[0148] As shown in FIG. 6, the zoom lens system of Example 6 is made up of a first lens group G1 having positive refracting power, a second lens group G2 having negative refracting power, a third lens group G3 having negative refracting power, a fourth lens group G4 having positive refracting power, a fifth lens group G5 having negative refracting power and a sixth lens group G6 having positive refracting power. For zooming from the wide-angle end to the telephoto end of the zoom lens system when focused on an object point at infinity, the first lens group G1 moves toward the image side of the zoom lens system in a convex reciprocation locus and reaches the telephoto end of the zoom lens system where it is located nearer to the object side than at the location of the wide-angle end, the second lens group G2 moves toward the image side, the third lens group G3, which is integrally provided with an aperture stop on its image side, moves toward the image side while the spacing between the second lens group G2 and the third lens group G3 becomes narrow, the fourth lens group G4 moves toward the object side, the fifth lens group G5 moves toward the object side in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the image side than at the location of the wide-angle end, and the sixth lens group G6 moves toward the object side in a convex reciprocation locus while the spacing between the fifth lens group G5 and the sixth lens group G6 becomes narrow, and reaches the telephoto end where it is located somewhat nearer to the object side than at the location of the wide-angle end. For focusing on a nearby subject, the sixth lens group G6 is designed to move out toward the object side of the system. More specifically, when the system is focused on a nearby substance at the wide-angle end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 7.9681 mm and when focused on a nearby subject at the telephoto end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 1.7655 mm.


[0149] In Example 6, the first lens group G1 is made up of a negative meniscus lens convex on its object side, a double-convex lens and a positive meniscus lens convex on its object side, the second lens group G2 is made up of a double-concave lens, a double-concave lens with an object-side surface thereof provided with a thin resin layer, thereby making that surface aspheric, and a doublet consisting of a negative meniscus lens convex on its image side and a positive meniscus lens convex on its image side, the third lens group G3 is made up of a negative meniscus lens convex on its image side and a stop, the fourth lens group G4 is made up of a double-convex lens and a doublet consisting of a negative meniscus lens convex on its object side and a double-convex lens, the fifth lens group G5 is made up of a doublet consisting of a double-concave lens and a positive meniscus lens convex on its object side, and the sixth lens group G6 is made up of a double-convex lens and a doublet consisting of a double-convex lens and a negative meniscus lens convex on its image side. Three aspheric surfaces are provided, one for the object-side resin layer surface of the double-concave lens in the second lens group G2, one for the object-side surface of the double-convex lens in the fourth lens group G4 and one for the object-side surface of the double-convex lens in the sixth lens group G6.


[0150] As shown in FIG. 7, the zoom lens system of Example 7 is made up of a first lens group G1 having positive refracting power, a second lens group G2 having negative refracting power, a third lens group G3 having negative refracting power, a fourth lens group G4 having positive refracting power, a fifth lens group G5 having negative refracting power and a sixth lens group G6 having positive refracting power. For zooming from the wide-angle end to the telephoto end of the zoom lens system when focused on an object point at infinity, the first lens group G1 moves toward the image side of the system in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the object side of the zoom lens system than at the location of the wide-angle end, the second lens group G2 moves toward the image side, the third lens group G3, which is integrally provided with an aperture stop on its image side, moves toward the image side while the spacing between the second lens group G2 and the third lens group G3 becomes narrow, the fourth lens group G4 moves toward the object side, and the fifth lens group G5 moves together with the sixth lens group G6 in a convex reciprocation locus and reaches the telephoto end where it is located somewhat nearer to the object side than at the location of the wide-angle end. For focusing on a nearby subject, the sixth lens group G6 is designed to move out toward the object side. More specifically, when the system is focused on a nearby subject at the wide-angle end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 7.4249 mm, and when focused on a nearby subject at the telephoto end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 3.9201 mm.


[0151] In Example 7, the first lens group G1 is made up of a negative meniscus lens convex on its object side, a double-convex lens and a positive meniscus lens convex on its object side, the second lens group G2 is made up of a negative meniscus lens convex on its object side, a double-concave lens with an object-side surface thereof provided with a thin resin layer thereby making that surface aspheric, and a doublet consisting of a negative meniscus lens convex on its image side and a positive meniscus lens convex on its image side, the third lens group G3 is made up of a negative meniscus lens convex on its image side and a stop, the fourth lens group G4 is made up of a double-convex lens and a doublet consisting of a double-concave lens and a double-convex lens, the fifth lens group G5 is made up of a doublet consisting of a double-concave lens and a positive meniscus lens convex on its object side, and the sixth lens group G6 is made up of a double-convex lens and a doublet consisting of a positive meniscus lens convex on its image side and a negative meniscus lens convex on its image side. Three aspheric surfaces are provided, one for the object-side resin layer surface of the double-concave lens in the second lens group G2, one for the object-side surface of the double-convex lens in the fourth lens group G4 and one for the object-side surface of the double-convex lens in the sixth lens group G6.


[0152] As shown in FIG. 7, the zoom lens system of Example 7 is made up of a first lens group G1 having positive refracting power, a second lens group G2 having negative refracting power, a third lens group G3 having negative refracting power, a fourth lens group G4 having positive refracting power, a fifth lens group G5 having negative refracting power and a sixth lens group G6 having positive refracting power. For zooming from the wide-angle end to the telephoto end of the system when focused on an object point at infinity, the first lens group G1 moves toward the image side of the system in a convex reciprocation locus and reaches the telephoto end where it is located on the object side of the system with respect to the location of the wide-angle end, the second lens group G2 moves toward the image side, the third lens group G3, which is integrally provided with an aperture stop on its image side, moves toward the image side while the spacing between the second lens group G2 and the third lens group G3 becomes narrow, the fourth lens group G4 moves toward the object side, and the fifth lens group G5 moves together with the sixth lens group G6 in a convex reciprocation locus and reaches the telephoto end where it is located somewhat on the object side with respect to the location of the wide-angle end. For focusing on a nearby subject, the sixth lens group G6 is designed to move toward the object side. More specifically, when the system is focused on a nearby subject at the wide-angle end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 7.4249 mm, and when focused on a nearby subject at the telephoto end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 3.9201 mm.


[0153] In Example 7, the first lens group G1 is made up of a negative meniscus lens convex on its object side, a double-convex lens and a positive meniscus lens convex on its object side, the second lens group G2 is made up of a negative meniscus lens convex on its object side, a double-concave lens with an object-side surface thereof provided with a thin resin layer thereby making that surface aspheric, and a doublet consisting of a negative meniscus lens convex on its image side and a positive meniscus lens convex on its image side, the third lens group G3 is made up of a negative meniscus lens convex on its image side and a stop, the fourth lens group G4 is made up of a double-convex lens and a doublet consisting of a double-concave lens and a double-convex lens, the fifth lens group G5 is made up of a doublet consisting of a double-concave lens and a positive meniscus lens convex on its object side, and the sixth lens group G6 is made up of a double-convex lens and a doublet consisting of a positive meniscus lens convex on its image side and a negative meniscus lens convex on its image side. Three aspheric surfaces are provided, one for the object-side resin layer surface of the double-concave lens in the second lens group G2, one for the object-side surface of the double-convex lens in the fourth lens group G4 and one for the object-side surface of the double-convex lens in the sixth lens group G6.


[0154] As shown in FIG. 8, the zoom lens system of Example 8 is made up of a first lens group G1 having positive refracting power, a second lens group G2 having negative refracting power, a third lens group G3 having negative refracting power, a fourth lens group G4 having positive refracting power, a fifth lens group G5 having negative refracting power and a sixth lens group G6 having positive refracting power. For zooming from the wide-angle end to the telephoto end of the zoom lens system when focused on an object point at infinity, the first lens group G1 moves toward the image side of the system in a convex reciprocation locus and reaches the telephoto end where it is located neater to the object side of the zoom lens system than at the location of the wide-angle end, the second lens group G2 moves toward the image side, the third lens group G3 is integrally provided with an aperture stop on its object side and remains fixed, the fourth lens group G4 moves toward the object side, the fifth lens group G5 remains fixed, and the sixth lens group G6 moves toward the object side. For focusing on a nearby subject, the sixth lens group G6 is designed to move out toward the object side. More specifically, when the zoom lens system is focused on a nearby subject at the wide-angle end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 8.5198 mm, and when focused on a nearby subject at the telephoto end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 1.3741 mm.


[0155] In Example 8, the first lens group G1 is made up of a negative meniscus lens convex on its object side, a double-convex lens and a positive meniscus lens convex on its object side, the second lens group G2 is made up of a double-concave lens, a double-concave lens with an object-side surface therein provided with a thin resin layer thereby making that surface aspheric, and a doublet consisting of a double-concave lens and a double-convex lens, the third lens group G3 is made up of a stop and a negative meniscus lens convex on its image side, the fourth lens group G4 is made up of a positive meniscus lens convex on its object side and a doublet consisting of a negative meniscus lens convex on its object side and a double-convex lens, the fifth lens group G5 is made up of a doublet consisting of a double-concave lens and a positive meniscus lens convex on its object side, and the sixth lens group G6 is made up of a double-convex lens and a doublet consisting of a double-convex lens and a negative meniscus lens convex on its image side. Three aspheric surfaces are provided, one for the object-side resin layer surface of the double-concave lens in the second lens group G2, one for the double-convex lens in the fourth lens group G4 and one for the object-side surface of the double-convex lens in the sixth lens group G6.


[0156] As shown in FIG. 9, the zoom lens system of Example 9 is made up of a first lens group G1 having positive refracting power, a second lens group G2 having negative refracting power, a fixed aperture stop, a third lens group G3 having positive refracting power and a fourth lens group G4 having positive refracting power. For zooming from the wide-angle end to the telephoto end of the system when focused on an object point at infinity, the first lens group G1 moves to the image side of the system in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the object side of the zoom lens system than at the location of the wide-angle end, the second lens group G2 moves toward the image side, the third lens group G3 moves toward the object side, and the fourth lens group G4 moves toward the object side while the spacing between the third lens group G3 and the fourth lens group G4 becomes wide. For focusing on a nearby subject, the fourth lens group G4 is designed to move out toward the object side. More specifically, when the system is focused on a nearby subject at the wide-angle end, the spacing between the third lens group G3 and the fourth lens group G4 is set at 1.3397 mm, and when focused on a nearby subject at the telephoto end, the spacing between the third lens group G3 and the fourth lens group G4 is set at 15.0854 mm.


[0157] In Example 9, the first lens group G1 is made of a negative meniscus lens convex on its object side, a double-convex lens and a positive meniscus lens convex on its object side, the second lens group G2 is made up of a negative meniscus lens convex on its object side, a double-concave lens with an image-side surface thereof provided with a thin resin layer thereby making that surface aspheric, and a doublet consisting of a negative meniscus lens convex on its object side and a double-convex lens, the third lens group G3, with the fixed stop located between the second lens group G2 and the third lens group G3, is made up of a positive meniscus lens convex on its object side and a doublet consisting of a negative meniscus lens convex on its object side and a double-convex lens, and the fourth lens group G4 is made up of a doublet consisting of a double-convex lens and a double-concave lens, a positive meniscus lens convex on its image side and a doublet consisting of a double-convex lens and a double-concave lens. Three aspheric surfaces are provided, one for the image-side resin layer surface of the double-concave lens in the second lens group G2, one for the object-side surface of the positive meniscus lens in the third lens group G3 and one for the object-side surface of the positive meniscus lens in the fourth lens group G4.


[0158] As shown in FIG. 10, the zoom lens system of Example 10 is made up of a first lens group G1 having positive refracting power, a second lens group G2 having negative refracting power, a third lens group G3 having negative refracting power, a fourth lens group G4 having positive refracting power, a fifth lens group G5 having negative refracting power and a sixth lens group G6 having positive refracting power. For zooming from the wide-angle end to the telephoto end of the zoom lens system when focused on an object point at infinity, the first lens group G1 moves toward the image side of the system in a convex reciprocation locus and reaches the telephoto end where it is located neater to the object side of the zoom lens system than at the location of the wide-angle end, the second lens group G2 moves toward the image side, the third lens group G3, which is integrally provided with an aperture stop on its image side, remains fixed, the fourth lens group G4 moves toward the object side, the fifth lens group G5 moves toward the object side in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the image side than at the location of the wide-angle end, and the sixth lens group G6 moves toward the object side in a concave reciprocation locus while the spacing between the fifth lens group G5 and the sixth lens group G6 becomes narrow and reaches the telephoto end where it is located somewhat neater to the image side than at the location of the wide-angle end. For focusing on a nearby subject, the sixth lens group G6 is designed to move out toward the object side of the zoom lens system. More specifically, when the zoom lens system is focused on a nearby subject at the wide-angle end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 8.1246 mm, and when focused on a nearby subject at the telephoto end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 2.3175 mm.


[0159] In Example 10, the first lens group G1 is made up of a negative meniscus lens convex on its object side, a double-convex lens and a positive meniscus lens convex on its object side, the second lens group G2 is made up of a double-concave lens with an image-side surface thereof provided with a thin resin layer thereby making that surface aspheric, a double-concave lens, a negative meniscus lens convex on its image side and two double-convex lenses, the third lens group G3 is made up of a negative meniscus lens convex on its image side and a stop, the fourth lens group G4 is made up of a double-convex lens and a doublet consisting of a negative meniscus lens convex on its object side and a double-convex lens, the fifth lens group G5 is made up of a double-concave lens and a positive meniscus lens convex on its object side, and the sixth lens group G6 is made up of a double-convex lens and a doublet consisting of a double-convex lens and a negative meniscus lens convex on its image side. Three aspheric surfaces are provided, one for the image-side resin layer surface of the double-concave lens in the second lens group G2, one for the object-side surface of the double-convex lens in the fourth lens group G4 and one for the object-side surface of the double-convex lens in the sixth lens group G6.


[0160] As shown in FIG. 11, the zoom lens system of Example 11 is made up of a first lens group G1 having positive refracting power, a second lens group G2 having negative refracting power, a third lens group G3 having negative refracting power, a fourth lens group G4 having positive refracting power, a fifth lens group G5 having negative refracting power and a sixth lens group G6 having positive refracting power. For zooming from the wide-angle end to the telephoto end of the zoom lens system when focused on an object point at infinity, the first lens group G1 moves toward the image side of the system in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the object side than at the location of the wide-angle end, the second lens group G2 moves toward the image side, the third lens group G3, which is integrally provided with an aperture stop on its image side, remains fixed, the fourth lens group G4 moves toward the object side of the system, the fifth lens group G5 moves toward the object side in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the object side than at the location of the wide-angle end, and the sixth lens group G6 moves toward the object side in a convex reciprocation locus while the spacing between the fifth lens group G5 and the sixth lens group G6 becomes narrow and then slightly wide and reaches the telephoto end where it is located somewhat nearer to the object side than at the location of the wide-angle end. For focusing on a nearby subject, the sixth lens group G6 is designed to move out toward the object side of the zoom lens system. More specifically, when the zoom lens system is focused on a nearby subject at the wide-angle end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 6.6911 mm, and when focused on a nearby subject at the telephoto end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 3.0700 mm.


[0161] In Example 11, the first lens group G1 is made up of two lenses, i.e., a negative meniscus lens convex on its object side and a positive meniscus lens convex on its object side, the second lens group G2 is made up of a negative meniscus lens convex on its object side, two double-concave lenses and a double-convex lens, the third lens group G3 is made up of a negative meniscus lens convex on its object side and a stop, the fourth lens group G4 is made up of a double-convex lens and a doublet consisting of a negative meniscus lens convex on its object side and a double-convex lens, the fifth lens group G5 is made up of a doublet consisting of a double-concave lens and a positive meniscus lens convex on its object side, and the sixth lens group G6 is made up of a double-convex lens and a doublet consisting of a double-convex lens and a negative meniscus lens convex on its image side. Three aspheric surfaces are used, one for the image-side surface of the double-convex lens in the second lens group G2, one for the object-side surface of the double-convex lens in the fourth lens group G4 and one for the image-side surface of the double-convex lens in the sixth lens group G6.


[0162] As shown in FIG. 12, the zoom lens system of Example 12 is made up of a first lens group G1 having positive refracting power, a second lens group G2 having negative refracting power, a third lens group G3 having negative refracting power, a fourth lens group G4 having positive refracting power, a fifth lens group G5 having negative refracting power and a sixth lens group G6 having positive refracting power. For zooming from the wide-angle end to the telephoto end of the zoom lens system when focused on an object point at infinity, the first lens group G1 moves toward the image side of the zoom lens system in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the object side of the system than at the location of the wide-angle end, the second lens group G2 moves to the image side, the third lens group G3, which has an aperture stop on its image side as an integral piece, remains fixed, the fourth lens group G4 moves toward the object side, the fifth lens group G5 moves toward the object side in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the object side than at the location of the wide-angle end, and the sixth lens group G6 moves toward the object side in a convex reciprocation locus while the spacing between the fifth lens group G5 and the sixth lens group G6 becomes narrow and then slightly wide, and reaches the telephoto end where it is located somewhat nearer to the object side than at the location of the wide-angle end. For focusing on a nearby subject, the sixth lens group G6 is designed to move out toward the object side of the system. More specifically, when the system is focused on a nearby subject at the wide-angle end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 6.0167 mm, and when focused on a nearby subject at the telephoto end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 2.1156 mm.


[0163] In Example 12, the first lens group G1 is made up of a negative meniscus lens convex on its object side and two positive meniscus lenses, each convex on its object side, the second lens group G2 is made up of a negative meniscus lens convex on its object side, two double-concave lenses and a double-convex lens, the third lens group G3 is made up of a double-concave lens and a stop, the fourth lens group G4 is made up of a double-convex lens and a doublet consisting of a negative meniscus lens convex on its object side and a positive meniscus lens convex on its object side, the fifth lens group G5 is made up of a doublet consisting of a double-concave lens and a positive meniscus lens convex on its object side, and the sixth lens group G6 is made up of a double-convex lens and a doublet consisting of a double-convex lens and a negative meniscus lens convex on its object side. Three aspheric surfaces are used, one for the object-side surface of the double-concave lens in the second lens group G2, one for the object-side surface of the double-convex lens in the fourth lens group G4 and one for the image-side surface of the double-convex lens in the sixth lens group G6.


[0164] As shown in FIG. 13, the zoom lens system of Example 13 is made up of a first lens group G1 having positive refracting power, a second lens group G2 having negative refracting power, a third lens group G3 having positive refracting power, a fourth lens group G4 having positive refracting power, a fifth lens group G5 having negative refracting power and a sixth lens group G6 having positive refracting power. For zooming from the wide-angle end to the telephoto end of the zoom lens system when focused on an object point at infinity, the first lens group G1 moves toward the image side of the zoom lens system in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the object side of the zoom lens system than at the location of the wide-angle end, the second lens group G2 moves toward the image side, the third lens group G3, which has an aperture stop on its object side as an integral piece, remains fixed, the fourth lens group G4 moves toward the object side, the fifth lens group G5 moves toward the object side in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the object side than at the location of the wide-angle end, and the sixth lens group G6 moves toward the object side while the spacing between the fifth lens group G5 and the sixth lens group G6 becomes narrow. For focusing on a nearby subject, the sixth lens group G6 is designed to move out toward the object side. More specifically, when the zoom lens system is focused on a nearby subject at the wide-angle end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 7.3354 mm, and when focused on a nearby subject at the telephoto end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 1.7386 mm.


[0165] In Example 13, the first lens group G1 is made up of a negative meniscus lens convex on its object side and two positive meniscus lenses, each convex on its object side, the second lens group G2 is made up of a negative meniscus lens convex on its object side, a double-concave lens, a double-concave lens with an object-side surface thereof provided with a thin resin layer thereby making that surface aspheric and a double-convex lens, the third lens group G3 is made up of a stop and a double-convex lens, the fourth lens group G4 is made up of a double-convex lens and a doublet consisting of a negative meniscus lens convex on its object side and a double-convex lens, the fifth lens group G5 is made up of a doublet consisting of a double-concave lens and a positive meniscus lens convex on its object side, and the sixth lens group G6 is made up of a double-convex lens and a doublet consisting of a positive meniscus lens convex on its image side and a negative meniscus lens convex on its image side. Three aspheric surfaces are used, one for the object-side resin layer surface of the double-concave lens in the second lens group G2, one for the object-side surface of the double-convex lens in the fourth lens group G4 and one for the object-side surface of the double-convex lens in the sixth lens group G6.


[0166] As shown in FIG. 14, the zoom lens system of Example 14 is made up of a first lens group G1 having positive refracting power, a second lens group G2 having negative refracting power, a fixed aperture stop, a third lens group G3 having positive refracting power, a fourth lens group G4 having negative refracting power and a fifth lens group G5 having positive refracting power. For zooming from the wide-angle end to the telephoto end of the zoom lens system when focused on an object point at infinity, the first lens group G1 moves toward the image side of the zoom lens system in a concave reciprocation locus and reaches the telephoto end where it is located nearer to the object side of the zoom lens system than at the location of the wide-angle end, the second lens group G2 moves toward the image side, the third lens group G3 moves toward the object side, the fourth lens group G4 moves toward the object side, and the fifth lens group G5 moves toward the object side while the spacing between the fourth lens group G4 and the fifth lens group G5 becomes narrow. For focusing on a nearby subject, the fifth lens group G5 is designed to move out toward the object side of the zoom lens system. More specifically, when the zoom lens system is focused on a nearby subject at the wide-angle end, the spacing between the fourth lens group G4 and the fifth lens group G5 is set at 7.5416 mm, and when focused on a nearby subject at the telephoto end, the spacing between the fourth lens group G4 and the fifth lens group G5 is set at 0.5503 mm.


[0167] In Example 14, the first lens group G1 is made up of a negative meniscus lens convex on its object side and two positive meniscus lenses, each convex on its object side, the second lens group G2 is made up of a negative meniscus lens convex on its object side, a double-concave lens, a doublet consisting of a double-concave lens and a negative meniscus lens convex on its object side and a double-convex lens, the third lens group G3, with the fixed stop located between the second lens group G2 and the third lens group G3, is made up of a double-convex lens and a doublet consisting of a negative meniscus lens convex on its object side and a double-convex lens, the fourth lens group G4 is made up of a doublet consisting of a double-concave lens and a positive meniscus lens convex on its object side, and the fifth lens group G5 is made up of a double-convex lens and a positive meniscus lens convex on its image side. Three aspheric surfaces are used, one for the object-side surface of the doublet in the second lens group G2, one for the object-side surface of the double-convex lens in the third lens group G3 and one for the object-side surface of the double-convex lens in the fifth lens group G5.


[0168] As shown in FIG. 15, the zoom lens system of Example 15 is made up of a first lens group G1 having positive refracting power, a second lens group G2 having negative refracting power, a fixed aperture stop, a third lens group G3 having positive refracting power, a fourth lens group G4 having negative refracting power and a fifth lens group G5 having positive refracting power. For zooming from the wide-angle end to the telephoto end of the zoom lens system when focused on an object point at infinity, the first lens group G1 moves toward the image side of the zoom lens system in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the object side of the zoom lens system than at the location of the wide-angle end, the second lens group G2 moves toward the image side, the third lens group G3 moves toward the object side, the fourth lens group G4 moves toward the object side, and the fifth lens group G5 moves toward the object side while the spacing between the fourth lens group G4 and the fifth lens group G5 becomes narrow. For focusing on a nearby subject, the fifth lens group G5 is designed to move out toward the object side of the zoom lens system. More specifically, when the zoom lens system is focused on a nearby subject on the wide-angle end, the spacing between the fourth lens group G4 and the fifth lens group G5 is set at 7.8923 mm, and when focused on a nearby subject on the telephoto end, the spacing between the fourth lens group G4 and the fifth lens group G5 is set at 2.3128 mm.


[0169] In Example 15, the first lens group G1 is made up of a negative meniscus lens convex on its object side and two positive meniscus lenses, each convex on its object side, the second lens group G2 is made up of a negative meniscus lens convex on its object side, a double-concave lens, a double-concave lens with an object-side surface thereof provided with a thin resin layer thereby making that surface aspheric and a double-convex lens, the third lens group G3, with the fixed stop located between the second lens group G2 and the third lens group G3, is made up of a double-convex lens and a doublet consisting of a negative meniscus lens convex on its object side and a double-convex lens, the fourth lens group G4 is made up of a doublet consisting of a double-concave lens and a positive meniscus lens convex on its object side, and the fifth lens group G5 is made up of a double-convex lens and a doublet consisting of a negative meniscus lens convex on its object side and a double-convex lens. Three aspheric surfaces are provided, one for the object-side resin layer surface of the double-concave lens in the second lens group G2, the object-side surface of the double-convex lens in the third lens group G3 and one for the object-side surface of the double-convex lens in the fifth lens group G5.


[0170] As shown in FIG. 16, the zoom lens system of Example 16 is composed of a first lens group G1 having positive refracting power, a second lens group G2 having negative refracting power, a third lens group G3 having negative refracting power, a fourth lens group G4 having positive refracting power, a fifth lens group G5 having negative refracting power and a sixth lens group G6 having positive refracting power. For zooming from the wide-angle end to the telephoto end of the zoom lens system when focused on an object point at infinity, the first lens group G1 moves toward the image side of the zoom lens system in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the object side of the zoom lens system than at the location of the wide-angle end, the second lens group G2 moves toward the image side, the third lens group G3, which has an aperture stop on its image side as an integral piece, remains fixed, the fourth lens group G4 moves toward the object side, the fifth lens group G5 moves toward the object side in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the object side than at the location of the wide-angle end, and the sixth lens group G6 moves toward the object side in a convex reciprocation locus while the fifth lens group G5 and the sixth lens group G6 becomes narrow and then slightly wide and reaches the telephoto end where it is located somewhat nearer to the object side than at the location of the wide-angle end. For focusing on a nearby subject, the sixth lens group G6 is designed to move out toward the object side of the system. More specifically, when the zoom lens system is focused on a nearby subject at the wide-angle end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 7.6961 mm, and when focused on a nearby subject at the telephoto end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 3.0968 mm.


[0171] In Example 16, the first lens group G1 is made up of a negative meniscus lens convex on its object side and two positive meniscus lenses, each convex on its object side, the second lens group G2 is made up of a negative meniscus lens convex on its object side, a double-concave lens, a double-convex lens and a negative meniscus lens convex on its image side, the third lens group G3 is made up of a double-concave lens and a stop, the fourth lens group G4 is made up of a double-convex lens and a doublet consisting of a negative meniscus lens convex on its object side and a double-convex lens, the fifth lens group G5 is made up of a doublet consisting of a double-concave lens and a positive meniscus lens convex on its object side, and the sixth lens group G6 is made up of a double-convex lens and a doublet consisting of a double-convex lens and a negative meniscus lens convex on its image side. Three aspheric surfaces are provided, one for the object-side surface of the double-concave lens in the second lens group G2, one for the object-side surface of the double-convex lens in the fourth lens group G4 and one for the image-side surface of the double-convex lens in the sixth lens group G6.


[0172] As shown in FIG. 17, the zoom lens system of Example 17 is composed of a first lens group G1 having positive refracting power, a second lens group G2 having negative refracting power, a third lens group G3 having negative refracting power, a fourth lens group G4 having positive refracting power, a fifth lens group G5 having negative refracting power and a sixth lens group G6 having positive refracting power. For zooming from the wide-angle end to the telephoto end of the zoom lens system when focused on an object point at infinity, the first lens group G1 moves toward the image side of the zoom lens system in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the object side of the zoom lens system than at the location of the wide-angle end, the second lens group G2 moves toward the image side, the third lens group G3, which has an aperture stop on its image side as an integral piece, remains fixed, the fourth lens group G4 moves toward the object side, the fifth lens group G5 moves toward the object side in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the object side than the location of the wide-angle end, and the sixth lens group G6 moves toward the object side in a convex reciprocation locus while the spacing between the fifth lens group G5 and the sixth lens group G6 becomes narrow and then slightly wide, and reaches the telephoto end where it is located somewhat nearer to the object side than at the location of the wide-angle end. For focusing on a nearby subject, the sixth lens group G6 is designed to move out toward the object side of the zoom lens system. More specifically, when the zoom lens system is focused on a nearby subject at the wide-angle end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 6.0079 mm, and when focused on a nearby subject at the wide-angle end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 2.6039 mm.


[0173] In Example 17, the first lens group G1 is made up of a negative meniscus lens convex on its object side and two positive meniscus lenses, each convex on its object side, the second lens group G2 is made up of a negative meniscus lens convex on its object side, two double-concave lenses and a double-convex lens, the third lens group G3 is made up of a doublet consisting of a double-concave lens and a positive meniscus lens convex on its object side and a stop, the fourth lens group G4 is made up of a double-convex lens and a doublet consisting of a negative meniscus lens convex on its object side and a positive meniscus lens convex on its object side, the fifth lens group G5 is made up of a doublet consisting of a double-concave lens and a positive meniscus lens convex on its object side, and the sixth lens group G6 is made up of a double-convex lens and a doublet consisting of a double-convex lens and a negative meniscus lens convex on its image side. Three aspheric surfaces are used, one for the object-side surface of the second double-concave lens in the second lens group G2, one for the object-side surface of the double-convex lens in the fourth lens group G4 and one for the image-side surface of the double-convex lens in the sixth lens group G6.


[0174] As shown in FIG. 18, the zoom lens system of Example 18 is composed of a first lens group G1 having positive refracting power, a second lens group G2 having negative refracting power, a third lens group G3 having negative refracting power, a fourth lens group G4 having positive refracting power, a fifth lens group G5,having negative refracting power and a fourth lens group G6. For zooming from the wide-angle end to the telephoto end of the zoom lens system when focused on an object point at infinity, the first lens group G1 moves toward the image side of the system in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the object side of the zoom lens system than at the location of the wide-angle end, the second lens group G2 moves toward the image side, the third lens group G3, which has an aperture stop on its image side as an integral piece, remains fixed, the fourth lens group G4 moves toward the object side, the fifth lens group G5 moves toward the object side in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the object side than at the location of the wide-angle end, and the sixth lens group G6 moves toward the object side in a convex reciprocation locus while the spacing between the fifth lens group G5 and the sixth lens group G6 becomes narrow and then slightly wide and reaches the telephoto end where it is located somewhat nearer to the object side than at the location of the wide-angle end. For focusing on a nearby object, the sixth lens group G6 is designed to move toward the object side. More specifically, when the system is focused on a nearby subject at the wide-angle end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 6.0177 mm, and when focused on a nearby subject, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 2.2983 mm.


[0175] In Example 18, the first lens group G1 is made up of a negative meniscus lens convex on its object side and two positive meniscus lenses, each convex on its object side, the second lens group G2 is made up of a negative meniscus lens convex on its object side, two double-concave lenses and a double-convex lens, the third lens group G3 is made up of a plano-concave lens and a stop, the fourth lens group G4 is made up of a double-convex lens and a doublet consisting of a negative meniscus lens convex on its object side and a positive meniscus lens convex on its object side, the fifth lens group G5 is made up of a doublet consisting of a double-concave lens and a positive meniscus lens convex on its object side, and the sixth lens group G6 is made up of a double-convex lens and a doublet consisting of a double-convex lens and a negative meniscus lens convex on its image side. Four aspheric surfaces are used, one for the object-side surface of the second double-concave lens in the second lens group G2, one for the image-side surface of the plano-concave lens in the third lens group G3, one for the object-side surface of the double-convex lens in the fourth lens group G4 and one for the image-side surface of the double-convex lens in the sixth lens group G6.


[0176] As shown in FIG. 19, the zoom lens system of Example 19 is composed of a first lens group G1 having positive refracting power, a second lens group G2 having negative refracting power, a fixed aperture stop, a third lens group G3 having positive refracting power and a fourth lens group G4 having positive refracting power. For zooming from the wide-angle end to the telephoto end of the zoom lens system when focused on an object point at infinity, the first lens group G1 moves toward the image side of the zoom lens system in a convex reciprocation locus and reaches the telephoto end where it is located nearer to object side of the zoom lens system than at the location of the wide-angle end, the second lens group G2 moves toward the image side, the third lens group G3 moves toward the object side, and the fourth lens group G4 moves toward the object side while the spacing between the third lens group G3 and the fourth lens group G4 becomes wide. For focusing on a nearby subject, the fourth lens group G4 is designed to move out toward the object side of the system.


[0177] In Example 19, the first lens group G1 is made up of a doublet consisting of a negative meniscus lens convex on its object side and a double-convex lens and a positive meniscus lens convex on its object side, and the second lens group G2 is made up of a negative meniscus lens convex on its object side, a double-concave lens and two double-convex lenses. The fixed stop is located between the second lens group G2 and the third lens group G3. The third lens group G3 is made up of a double-convex lens and a doublet consisting of a positive meniscus lens convex on its object side and a negative meniscus lens convex on its object side, and the fourth lens group G4 is made up of a positive meniscus lens convex on its object side and a doublet consisting of a negative meniscus lens convex on its object side and a double-convex lens. Three aspheric surfaces are provided, one for the image-side surface of the double-concave lens in the second lens group G2, one for the object-side surface of the double-convex lens in the third lens group G3 and one for the surface located nearest to the image side in the fourth lens group G4.


[0178] As shown in FIG. 20, the zoom lens system of Example 20 is composed of a first lens group G1 having positive refracting power, a second lens group G2 having negative refracting power, a fixed aperture stop, a third lens group G3 having positive refracting power, a fourth lens group G4 having negative refracting power and a fifth lens group G5. For zooming from the wide-angle end to the telephoto end of the zoom lens system when focused on an object point at infinity, the first lens group G1 moves toward the image side of the zoom lens system in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the object side of the system than at the location of the wide-angle end, the second lens group G2 moves toward the image side, the third lens group G3 moves toward the object side, the fourth lens group G4 moves toward the object side while the spacing between the third lens group G3 and the fourth lens group G4 becomes wide, and the fifth lens group G5 moves toward the object side while the spacing between the fourth lens group G4 and the fifth lens group G5 becomes narrow and then slightly wide. For focusing on a nearby subject, the fifth lens group G5 is designed to move out toward the object side.


[0179] In Example 20, the first lens group G1 is made up of a doublet consisting of a negative meniscus lens convex on its object side and a double-convex lens and a positive meniscus lens convex on its object side, and the second lens group G2 is made up of a negative meniscus lens convex on its object side, a double-concave lens and a doublet consisting of a negative meniscus lens convex on its object side and a double-convex lens. The fixed stop is located between the second lens group G2 and the third lens group G3. The third lens group G3 is made up of a double-convex lens and a doublet consisting of a double-convex lens and a double-concave lens, the fourth lens group G4 is made up of a doublet consisting of a positive meniscus lens convex on its image side and a double-concave lens, and the fifth lens group G5 is made up of a doublet consisting of a double-concave lens and a double-convex lens and a double-convex lens. Three aspheric surfaces are provided, one for the image-side surface of the negative meniscus lens in the second lens group G2, one for the surface of the doublet in the third lens group G3, which is located nearest to the object side, and one for the surface of the doublet in the fifth lens group G5, which is located nearest to the image side.


[0180] As shown in FIG. 21, the zoom lens system of Example 21 is composed of a first lens group G1 having positive refracting power, a second lens group G2 having negative refracting power, a third lens group G3 having negative refracting power, a fourth lens group G4 having positive refracting power, a fifth lens group G5 having negative refracting power and a sixth lens group G5 having positive refracting power. For zooming from the wide-angle end to the telephoto end of the zoom lens system when focused on an object point at infinity, the first lens group G1 moves toward the image side of the zoom lens system in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the image side than at the location of the wide-angle end, the second lens group G2 moves toward the image side, the third lens group G3, which has an aperture stop on its object side as an integral piece, remains fixed, the fourth lens group G4 moves toward the object side, the fifth lens group G5 moves toward the object side while the spacing between the spacing between the fourth lens group G4 and the fifth lens group G5 becomes wide, and the sixth lens group G6 moves toward the object side while the spacing between the fifth lens group G5 and the sixth lens group G6 becomes slightly wide and then slightly narrow. For focusing on a nearby subject, the sixth lens group G6 is designed to move out toward the object side.


[0181] In Example 21, the first lens group G1 is made up of a doublet consisting of a negative meniscus lens convex on its object side and a double-convex lens, the second lens group G2 is made up of a negative meniscus lens convex on its object side, two double-concave lenses and a double-convex lens, the third lens group G3 is made up of a stop and a negative meniscus lens convex on its image side, the fourth lens group G4 is made up of a positive meniscus lens convex on its object side and a doublet consisting of a double-convex lens and a double-concave lens, the fifth lens group G5 is made up of a doublet consisting of a positive meniscus lens convex on its object side and a negative meniscus lens convex on its object side, and the sixth lens group G6 is made up of a double-convex lens and a doublet consisting of a negative meniscus lens convex on its image side and a double-convex lens. Three aspheric surfaces are provided, one for the image-side surface of the negative meniscus lens in the second lens group G2, one for the surface of the doublet in the fourth lens group G4, which is located nearest to the image side, and one for the image-side surface of the double-convex lens in the sixth lens group G6.


[0182] As shown in FIG. 22, the zoom lens system of Example 22 is composed of a first lens group G1 having positive refracting power, a second lens group G2 having negative refracting power, a third lens group G3 having negative refracting power, a fourth lens group G4 having positive refracting power, a fifth lens group G5 having negative refracting power and a sixth lens group G6 having positive refracting power. For zooming from the wide-angle end to the telephoto end of the zoom lens system when focused on an object point at infinity, the first lens group G1 moves toward the image side of the zoom lens system in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the object side of the zoom lens system than at the location of the wide-angle end, the second lens group G2 moves toward the image side, the third lens group G3, which has an aperture stop on its image side as an integral piece, remains fixed, the fourth lens group G4 moves toward the object side, the fifth lens group G5 moves toward the image side, and the sixth lens group G6 moves toward the object side in a convex reciprocation locus while the spacing between the fifth lens group G5 and the sixth lens group G6 becomes narrow and reaches the telephoto end where it is located somewhat nearer to the object side than at the location of the wide-angle end. For focusing on a nearby subject, the sixth lens group G6 is designed to move out toward the object side. More specifically, when the zoom lens system is focused on a nearby subject at the wide-angle end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 10.6679 mm, and when focused on a nearby subject at the telephoto end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 1.0776 mm.


[0183] In Example 22, the first lens group G1 is made up of a negative meniscus lens convex on its object side, a double-convex lens and a positive meniscus lens convex on its object side, the second lens group G2 is made up of a negative meniscus lens convex on its object side, a double-concave lens with an image-side surface thereof provided with a thin resin layer thereby making that surface aspheric and a doublet consisting of a negative meniscus lens convex on its image side and a positive meniscus lens convex on its image side, the third lens group G3 is made up of a negative meniscus lens convex on its image side and a stop, the fourth lens group G4 is made up of a double-convex lens and a doublet consisting of a negative meniscus lens convex on its object side and a double-convex lens, the fifth lens group G5 is made up of a doublet consisting of a double-concave lens and a positive meniscus lens convex on its object side, and the sixth lens group G6 is made up of a double-convex lens and a doublet consisting of a double-convex lens and a negative meniscus lens convex on its image side. Three aspheric surfaces are provided, one for the object-side resin layer surface of the double-concave lens in the second lens group G2, the object-side surface of the double-convex lens in the fourth lens group G4 and one for the object-side surface of the double-convex lens in the sixth lens group G6.


[0184] As shown in FIG. 23, the zoom lens system of Example 23 is composed of a first lens group G1 having positive refracting power, a second lens group G2 having negative refracting power, a third lens group G3 having negative refracting power, a fourth lens group G4 having positive refracting power, a fifth lens group G5 having negative refracting power and a sixth lens group G6 having positive refracting power. For zooming from the wide-angle end to the telephoto end of the zoom lens system when focused on an object point at infinity, the first lens group G1 moves toward the image side of the zoom system in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the object side of the system than at the location of the wide-angle end, the second lens group G2 moves toward the image side, the third lens group G3, which has an aperture stop on its image side as an integral piece, remains fixed, the fourth lens group G4 moves toward the object side, the fifth lens group G5 moves toward the image side, and the sixth lens group G6 moves toward the object side in a convex reciprocation locus while the spacing between the fifth lens group G5 and the sixth lens group G6 becomes narrow and reaches the telephoto end where it is located somewhat nearer to the object side than at the location of the wide-angle end. For focusing on a nearby subject, the sixth lens group G6 is designed to move out toward the object side. More specifically, when the system is focused on a nearby subject at the wide-angle end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 9.3998 mm, and when focused on a nearby subject at the telephoto end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 0.9516 mm.


[0185] In Example 23, the first lens group G1 is made up of a negative meniscus lens convex on its object side and two positive meniscus lenses, each convex on its object side, the second lens group G2 is made up of a negative meniscus lens convex on its object side, a negative meniscus lens convex on its image side and a doublet consisting of a negative meniscus lens convex on its image side and a positive meniscus lens convex on its image side, the third lens group G3 is made up of a negative meniscus lens convex on its image side and a stop, the fourth lens group G4 is made up of a double-convex lens and a doublet consisting of a negative meniscus lens convex on its object side and a double-convex lens, the fifth lens group G5 is made up of a doublet consisting of a double-concave lens and a positive meniscus lens convex on its object side, and the sixth lens group G6 is made up of a double-convex lens and a doublet consisting of a double-convex lens and a negative meniscus lens convex on its image side. Three aspheric surfaces are provided, one for the object-side surface of the negative meniscus lens in the second lens group G2, one for the object-side surface of the double-convex lens in the fourth lens group G4 and one for the object-side surface of the double-convex lens in the sixth lens group G6.


[0186] As shown in FIG. 24, the zoom lens system of Example 24 is composed of a first lens group having positive refracting power, a second lens group G2 having negative refracting power, a third lens group G3 having negative refracting power, a fourth lens group G4 having positive refracting power, a fifth lens group G5 having negative refracting power and a sixth lens group G6 having positive refracting power. For zooming from the wide-angle end to the telephoto end of the system when focused on an object point at infinity, the first lens group G1 moves toward the image side of the zoom lens system in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the object side of the system than at the position of the wide-angle end, the second lens group G2 moves toward the image side, the third lens group G3, which has an aperture stop on its image side as an integral piece, remains fixed, the fourth lens group G4 moves toward the object side, the fifth lens group G5 moves toward the image side, and the sixth lens group G6 moves toward the object side in a convex reciprocation locus while the spacing between the fifth lens group G5 and the sixth lens group G6 becomes narrow and reaches the telephoto end where it is located somewhat nearer to the object side than at the position of the wide-angle end. For focusing on a nearby subject, the sixth lens group G6 is designed to move out toward the object side of the system. More specifically, when the system is focused on a nearby subject at the wide angle end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 9.73471 mm, and when focused on a nearby subject at the telephoto end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 0.8531 mm.


[0187] In Example 24, the first lens group G1 is made up of a negative meniscus lens convex on its object side, a double-convex lens and a positive meniscus lens convex on its object side, the second lens group G2 is made up of a negative meniscus lens convex on its object side, a negative meniscus lens convex on its image side and a doublet consisting of a negative meniscus lens convex on its image side and a positive meniscus lens convex on its image side, the third lens group G3 is made up of a negative meniscus lens convex on its image side and a stop, the fourth lens group G4 is made up of a double-convex lens and a doublet consisting of a negative meniscus lens convex on its object side and a double-convex lens, the fifth lens group G5 is made up of a doublet consisting of a double-concave lens and a positive meniscus lens convex on its object side, and the sixth lens group G6 is made up of a double-convex lens and a doublet consisting of double-convex lens and a negative meniscus lens convex on its image side. Three aspheric surfaces are provided, one for the image-side surface of the negative meniscus lens in the second lens group G2, which lens is convex on its image side, one for the object-side surface of the double-convex lens in the fourth lens group G4, and one for the object-side surface of the double-convex lens in the sixth lens group G6.


[0188] As shown in FIG. 25, the zoom lens system of Example 25 is composed of a first lens group G1 having positive refracting power, a second lens group G2 having negative refracting power, a third lens group G3 having negative refracting power, a fourth lens group G4 having positive refracting power, a fifth lens group G5 having negative refracting power and a sixth lens group G6 having positive refracting power. For zooming from the wide-angle end to the telephoto end of the zoom lens system when focused on an object point at infinity, the first lens group G1 moves toward the image side of the zoom lens system in a convex reciprocation locus and reaches the telephoto end where it is located nearer to the object side of the zoom lens system than at the position of the wide-angle end, the second lens group G2 moves toward the image side, the third lens group G3, which has an aperture stop on its image side as an integral piece, remains fixed, the fourth lens group G4 moves toward the object side, the fifth lens group G5 moves toward the image side, and the sixth lens group G6 moves toward the object side while the spacing between the fifth lens group G5 and the sixth lens group G6 becomes narrow and reaches the telephoto end where it is located somewhat nearer to the image side than at the position of the wide-angle end. For focusing on a nearby subject, the sixth lens group G6 is designed to move out toward the object side. More specifically, when the system is focused on a nearby subject at the wide-angle end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 7.9914 mm, and when focused on a nearby subject at the telephoto end, the spacing between the fifth lens group G5 and the sixth lens group G6 is set at 1.4726 mm.


[0189] In Example 25, the first lens group G1 is made up of a negative meniscus lens convex on its object side, a double-convex lens and a positive meniscus lens convex on its object side, the second lens group G2 is made up of a negative meniscus lens convex on its object side, a double-concave lens and a doublet consisting of a double-concave lens and a double-convex lens, the third lens group G3 is made up of a negative meniscus lens convex on its image side and a stop, the fourth lens group G4 is made up of a double-convex lens and a doublet consisting of a negative meniscus lens convex on its object side and a double-convex lens, the fifth lens group G5 is made up of a doublet consisting of a double-concave lens and a positive meniscus lens convex on its object side, and the sixth lens group G6 is made up of a double-convex lens and a doublet consisting of a double-convex lens and a negative meniscus lens convex on its image side. Three aspheric surfaces are provided, one for the surface of the doublet in the second lens group G2, which is located nearest to the image side, one for the object-side surface of the double-convex lens in the fourth lens group G4 and one for the object-side surface of the double-convex lens in the sixth lens group G6.


[0190] Throughout Examples 1 to 25, it is acceptable to make the amount of focusing movement larger than exemplified above, thereby focusing the system on a more nearby subject.


[0191] Enumerated below are the data on each example. However, it is noted that the symbols used hereinafter but not hereinbefore have the following meanings.


[0192] f is the focal length of the zoom lens system, ω is the half field angle of the system, FNO is the F-number of the system, W is the wide-angle end of the system, WS is an intermediate state between the wide-angle end and a standard state (the geometric means of the wide-angle end and the standard state), S is the standard state, ST is an intermediate state between the standard state and the telephoto end of the system, T is the telephoto end of the system, r1, r2 . . . are the radii of curvature of the respective lens surfaces, d1, d2 . . . are the spacing between adjacent lens surfaces, nd1, nd2 . . . are the d-line refractive indices of the respective lenses, and νd1, νd2 . . . are the Abbe constants of the respective lenses. Here let x stand for an optical axis where the direction of propagation of light is positive and y represent a direction perpendicular to the optical axis. Then, aspheric surface shape is given by




x
=(y2/r)/[1+{1−(K+1)(y/r)2}1/2]+A4y4+A6y6+A8y8+A10y10



[0193] where r is a paraxial radius of curvature, K is a conical coefficient, and A4, A6, A8 and A10 are the fourth, sixth, eighth and tenth aspherical coefficients.



EXAMPLE 1

[0194]

1
















 r1 = 144.6796
 d1 = 2.6000
 nd1 = 1.84666
 νd1 = 23.78


 r2 = 82.7855
 d2 = 0.2000


 r3 = 86.4734
 d3 = 6.6250
 nd2 = 1.49700
 νd2 = 81.54


 r4 = −587.8788
 d4 = 0.2000


 r5 = 67.2317
 d5 = 4.9655
 nd3 = 1.69680
 νd3 = 55.53


 r6 = 245.5595
 d6 =



(Variable)


 r7 = −2.080 × 104
 d7 = 1.7000
 nd4 = 1.77250
 νd4 = 49.60


 r8 = 17.9014
 d8 = 8.5657


 r9 = −66.4539 (Aspheric)
 d9 = 0.2000
 nd5 = 1.53508
 νd5 = 40.94


r10 = −145.6382
d10 = 1.3000
 nd6 = 1.77250
 νd6 = 49.60


r11 = 275.5575
d11 = 4.1902


r12 = −23.6269
d12 = 1.1790
 nd7 = 1.48749
 νd7 = 70.23


r13 = −120.2094
d13 = 4.4826
 nd8 = 1.84666
 νd8 = 23.78


r14 = −36.0216
d14 =



(Variable)


r15 = −13.3441
d15 = 1.3000
 nd9 = 1.77250
 νd9 = 49.60


r16 = −14.7782
d16 = 1.0476


r17 = ∞ (Stop)
d17 =



(Variable)


r18 = 22.2411 (Aspheric)
d18 = 5.1519
nd10 = 1.49700
νd10 = 81.54


r19 = −44.3261
d19 = 0.1026


r20 = 66.0894
d20 = 1.1010
nd11 = 1.80610
νd11 = 40.92


r21 = 17.8460
d21 = 5.1279
nd12 = 1.49700
νd12 = 81.54


r22 = −87.9421
d22 =



(Variable)


r23 = −55.9458
d23 = 0.9000
nd13 = 1.51633
νd13 = 64.14


r24 = 13.4125
d24 = 3.2354
nd14 = 1.84666
νd14 = 23.78


r25 = 19.3681
d25 =



(Variable)


r26 = 26.8826 (Aspheric)
d26 = 4.2125
nd15 = 1.49700
νd15 = 81.54


r27 = −27.8744
d27 = 0.1500


r28 = 279.7814
d28 = 4.1538
nd16 = 1.61800
νd16 = 63.33


r29 = −15.8089
d29 = 1.0000
nd17 = 1.84666
νd17 = 23.78


r30 = −57.4983
d30 =



(Variable)


r31 = ∞
d31 =
nd18 = 1.51633
νd18 = 64.14



16.0000


r32 = ∞
d32 = 1.0000


r33 = ∞
d33 = 2.6000
nd19 = 1.54771
νd19 = 62.84


r34 = ∞
d34 = 1.0000


r35 = ∞
d35 = 0.7500
nd20 = 1.51633
νd20 = 64.14


r36 = ∞
d36 = 1.2400


r37 = ∞










[0195] Aspherical Coefficients


[0196] 9 th surface


[0197] K=0


[0198] A4=2.1263×10−5


[0199] A6=1.5727×10−8


[0200] A8=3.9610×10−11


[0201] A10=0.0000


[0202] 18 th surface


[0203] K=0


[0204] A4=−1.9875×10−5


[0205] A6=−1.3029×10−8


[0206] A8=5.1888×10−11


[0207] A10=0.0000


[0208] 26 th surface


[0209] K=0


[0210] A4=−1.7061×10−5


[0211] A6=−8.7539×10−9


[0212] A8=1.1345×10−10


[0213] A10=0.0000


[0214] Zooming Data (∞)
2WWSSSTTf (mm)7.2600012.9999923.2999741.7298474.74939FNO2.80003.37953.50003.50003.5000ω (° )38.4513.044.12d61.6886910.5670129.8576447.1396157.82811d1444.7656923.2831412.259746.308422.57394d1719.0023211.350268.661006.270170.99971d221.500007.8391511.9794716.0405022.86634d258.263238.968156.466945.082225.08574d304.692465.300466.350606.065124.50622



EXAMPLE 2

[0215]

3
















 r1 = 82.4483
 d1 = 2.6000
 nd1 = 1.84666
 νd1 = 23.78


 r2 = 57.4502
 d2 = 0.1000


 r3 = 57.9164
 d3 = 7.1329
 nd2 = 1.49700
 νd2 = 81.54


 r4 = 284.4315
 d4 = 0.2000


 r5 = 69.2991
 d5 = 5.3163
 nd3 = 1.60311
 νd3 = 60.64


 r6 = 400.4019
 d6 =



(Variable)


 r7 = −1559.7350
 d7 = 1.5000
 nd4 = 1.77250
 νd4 = 49.60


 r8 = 18.3563
 d8 = 8.8487


 r9 = −51.0656
 d9 = 1.3643
 nd5 = 1.77250
 νd5 = 49.60


r10 = 89.9326
d10 = 0.2000
 nd6 = 1.53508
 νd6 = 40.94


r11 = 56.6440 (Aspheric)
d11 = 2.9409


r12 = −70.2481
d12 = 1.1135
 nd7 = 1.48749
 νd7 = 70.23


r13 = −351.6349
d13 = 3.8722
 nd8 = 1.84666
 νd8 = 23.78


r14 = −41.4750
d14 =



(Variable)


r15 = −21.7766
d15 = 1.0673
 nd9 = 1.69680
 νd9 = 55.53


r16 = −24.1145
d16 = 1.4225


r17 = ∞ (Stop)
d17 =



(Variable)


r18 = 21.1358 (Aspheric)
d18 = 5.4704
nd10 = 1.49700
νd10 = 81.54


r19 = −79.1895
d19 = 0.1774


r20 = 47.1634
d20 = 1.1410
nd11 = 1.80440
νd11 = 39.59


r21 = 15.0512
d21 = 3.4835
nd12 = 161800
νd12 = 63.33


r22 = −184.9380
d22 =



(Variable)


r23 = −74.7571
d23 = 0.9000
nd13 = 1.51633
νd13 = 64.14


r24 = 11.7718
d24 = 1.9155
nd14 = 1.84666
νd14 = 23.78


r25 = 17.1123
d25 =



(Variable)


r26 = 37.8693 (Aspheric)
d26 = 3.4588
nd15 = 1.49700
νd15 = 81.54


r27 = −21.7737
d27 = 0.1500


r28 = −131.6293
d28 = 3.7575
nd16 = 1.61800
νd16 = 63.33


r29 = −12.5491
d29 = 1.0000
nd17 = 1.84666
νd17 = 23.78


r30 = −38.2936
d30 =



(Variable)


r31 = ∞
d31 =
nd18 = 1.51633
νd18 = 64.14



16.0000


r32 = ∞
d32 = 1.0000


r33 = ∞
d33 = 2.6000
nd19 = 1.54771
νd19 = 62.84


r34 = ∞
d34 = 1.0000


r35 = ∞
d35 = 0.7500
nd20 = 1.51633
νd20 = 64.14


r36 = ∞
d36 = 1.2400


r37 = ∞










[0216] Aspherical Coefficients


[0217] 11 th surface


[0218] K=0


[0219] A4=−2.3956×10−5


[0220] A6=1.1363×10−8


[0221] A8=−2.9304×10−11


[0222] A10=0.0000


[0223] 18 th surface


[0224] K=0


[0225] A4=−1.9310×10−5


[0226] A6=−5.6603×10−9


[0227] A8=−5.6829×10−11


[0228] A10=0.0000


[0229] 26 th surface


[0230] K=0


[0231] A4=−1.9084×10−5


[0232] A6=8.1108×10−9


[0233] A8=2.2527×10−10


[0234] A10=0.0000


[0235] Zooming Data (∞)
4WWSSSTTf (mm)7.259912.9999823.2999441.7297774.74923FNO2.80003.07733.40403.50003.5000ω (° )38.4713.054.09d62.0412912.0345630.3570047.3170758.11117d1452.0835923.8013512.151205.171372.10989d1715.9675411.837668.877426.747171.12789d221.500004.355767.4981110.6419317.10388d257.961977.072845.580794.445195.93947d304.693396.856638.166588.288615.95167



EXAMPLE 3

[0236]

5
















 r1 = 79.8928
 d1 = 2.6000
 nd1 = 1.84666
 νd1 = 23.78


 r2 = 56.5419
 d2 = 0.0932


 r3 = 56.8568
 d3 = 7.2921
 nd2 = 1.49700
 νd2 = 81.54


 r4 = 279.2946
 d4 = 0.2000


 r5 = 71.4740
 d5 = 5.1087
 nd3 = 1.60311
 νd3 = 60.64


 r6 = 368.5676
 d6 =



(Variable)


 r7 = 297.1098
 d7 = 1.5000
 nd4 = 1.77250
 νd4 = 49.60


 r8 = 16.7226
 d8 = 8.2214


 r9 = −58.5814
 d9 = 1.3643
 nd5 = 1.77250
 νd5 = 49.60


r10 = 42.9833
d10 = 2.8172


r11 = 44.9540
d11 = 2.4853
 nd6 = 1.68893
 νd6 = 31.07


r12 = 67.5910
d12 = 0.5000
 nd7 = 1.53508
 νd7 = 40.94


r13 = 60.4446 (Aspheric)
d13 = 2.4132


r14 = −152.6589
d14 = 2.7489
 nd8 = 1.84666
 νd8 = 23.78


r15 = −43.1824
d15 =



(Variable)


r16 = 1521.7545
d16 = 1.2383
 nd9 = 1.69680
 νd9 = 55.53


r17 = 103.2631
d17 = 1.3581


r18 = ∞ (Stop)
d18 =



(Variable)


r19 = 19.8319 (Aspheric)
d19 = 6.0797
nd10 = 1.49700
νd10 = 81.54


r20 = −98.1431
d20 = 0.1774


r21 = 41.2385
d21 = 1.1410
nd11 = 1.80440
νd11 = 39.59


r22 = 13.6120
d22 = 5.6638
nd12 = 1.60311
νd12 = 60.64


r23 = −105.3016
d23 =



(Variable)


r24 = −60.3378
d24 = 0.9000
nd13 = 1.51633
νd13 = 64.14


r25 = 11.2684
d25 = 2.0556
nd14 = 1.84666
νd14 = 23.78


r26 = 16.0592
d26 =



(Variable)


r27 = 57.5023
d27 = 3.0046
nd15 = 1.49700
νd15 = 81.54


r28 = −29.3958 (Aspheric)
d28 = 0.1500


r29 = 60.6802
d29 = 4.8459
nd16 = 1.60311
νd16 = 60.64


r30 = −12.9748
d30 = 1.0000
nd17 = 1.84666
νd17 = 23.78


r31 = −47.6191
d31 =



(Variable)


r32 = ∞
d32 =
nd18 = 1.51633
νd18 = 64.14



16.0000


r33 = ∞
d33 = 1.0000


r34 = ∞
d34 = 2.6000
nd19 = 1.54771
νd19 = 62.84


r35 = ∞
d35 = 1.0000


r36 = ∞
d36 = 0.7500
nd20 = 1.51633
νd20 = 64.14


r37 = ∞
d37 = 1.2400


r38 = ∞










[0237] Aspherical Coefficients


[0238] 13 th surface


[0239] K=0


[0240] A4=−1.4437×10−5


[0241] A6=2.9795×10−9


[0242] A8=−9.7997×10−12


[0243] A10=0.0000


[0244] 19 th surface


[0245] K=0


[0246] A4−1.9829×10−5


[0247] A6=−1.2490×10−9


[0248] A8=9.5912×10−12


[0249] A10=0.0000


[0250] 28 th surface


[0251] K=0


[0252] A4=−8.0968×10−6


[0253] A6=−1.4115×10−8


[0254] A8=−3.7788×10−10


[0255] A10=0.0000


[0256] Zooming Data (∞)
6WWSSSTTf (mm)7.2600213.0000323.3000841.7303374.75116FNO2.80033.08383.47423.50033.5007ω (° )38.4213.054.11d61.3600612.4983430.2182447.7433258.25431d1554.9639924.8999212.036114.747291.70314d1817.1433612.832909.248216.812491.02608d231.500003.505706.357328.9213016.08346d267.833567.528706.607335.981906.80232d315.025767.635389.289819.786997.59082



EXAMPLE 4

[0257]

7
















 r1 = 81.6544
 d1 = 2.6000
 nd1 = 1.84666
 νd1 = 23.78


 r2 = 54.5219
 d2 = 0.0918


 r3 = 55.1373
 d3 = 6.6789
 nd2 = 1.60311
 νd2 = 60.64


 r4 = 170.0871
 d4 = 0.2000


 r5 = 63.9518
 d5 = 5.5295
 nd3 = 1.60311
 νd3 = 60.64


 r6 = 261.7938
 d6 =



(Variable)


 r7 = 135.9397
 d7 = 1.5000
 nd4 = 1.77250
 νd4 = 49.60


 r8 = 18.6691
 d8 = 7.1069


 r9 = −77.9436
 d9 = 1.3643
 nd5 = 1.77250
 νd5 = 49.60


r10 = 29.3916
d10 = 3.6128


r11 = −136.6311 (Aspheric)
d11 = 2.6052
 nd6 = 1.68893
 νd6 = 31.07


r12 = −93.2719
d12 = 1.2000
 nd7 = 1.77250
 νd7 = 49.60


r13 = 48.4132
d13 = 0.1500


r14 = 40.2538
d14 = 5.6753
 nd8 = 1.68893
 νd8 = 31.07


r15 = −41.2699
d15 =



(Variable)


r16 = ∞ (Stop)
d16 =



(Variable)


r17 = 20.5800 (Aspheric)
d17 = 3.1262
 nd9 = 1.49700
 νd9 = 81.54


r18 = −89.3640
d18 = 0.1500


r19 = 221.1623
d19 = 3.2743
nd10 = 1.48749
νd10 = 70.23


r20 = −22.6962
d20 = 1.0743
nd11 = 1.69895
νd11 = 30.13


r21 = −65.3546
d21 =



(Variable)


r22 = −44.1685
d22 = 2.2362
nd12 = 1.84666
νd12 = 23.78


r23 = −17.9114
d23 = 0.9000
nd13 = 1.51633
νd13 = 64.14


r24 = 19.1017
d24 =



(Variable)


r25 = 26.6661 (Aspheric)
d25 = 3.6847
nd14 = 1.49700
νd14 = 81.54


r26 = −34.1574
d26 = 0.1500


r27 = 52.2108
d27 = 4.2853
nd15 = 1.49700
νd15 = 81.54


r28 = −14.7656
d28 = 1.2000
nd16 = 1.80518
νd16 = 25.42


r29 = −55.0799
d29 =



(Variable)


r30 = ∞
d30 =
nd17 = 1.51633
νd17 = 64.14



16.0000


r31 = ∞
d31 = 1.0000


r32 = ∞
d32 = 2.6000
nd18 = 1.54771
νd18 = 62.84


r33 = ∞
d33 = 1.0000


r34 = ∞
d34 = 0.7500
nd19 = 1.51633
νd19 = 64.14


r35 = ∞
d35 = 1.2400


r36 = ∞










[0258] Aspherical Coefficients


[0259] 11 th surface


[0260] K=0


[0261] A4=1.0139×10−5


[0262] A6=3.2872×10−9


[0263] A8=−1.1023×10−11


[0264] A10=0.0000


[0265] 17 th surface


[0266] K=0


[0267] A4=−1.7036×10−5


[0268] A6=−1.7437×10−8


[0269] A8=4.5946×10−11


[0270] A10=0.0000


[0271] 25 th surface


[0272] K=0


[0273] A4=3.4248×10−6


[0274] A6=1.4711×10−8


[0275] A8=4.5298×10−10


[0276] A10=0.0000


[0277] Zooming Data (∞)
8WWSSSTTf (mm)7.2599923.2999274.74889FNO2.80003.58013.5000ω (° )38.5413.224.14d61.0000014.8979331.0552147.1274259.32091d1552.3055629.1376615.907127.484622.50000d1620.2371412.060387.383505.166251.27216d213.727675.352708.3203610.8953115.89787d243.242867.151166.720195.063105.57919d294.692117.335549.4757310.775139.15056



EXAMPLE 5

[0278]

9
















 r1 = 78.1210
 d1 = 2.6000
 nd1 = 1.84666
 νd1 = 23.78


 r2 = 52.5351
 d2 = 0.0776


 r3 = 53.2073
 d3 = 6.8025
 nd2 = 1.60311
 νd2 = 60.64


 r4 = 159.3705
 d4 = 0.2000


 r5 = 65.8776
 d5 = 5.5331
 nd3 = 1.60311
 νd3 = 60.64


 r6 = 303.8063
 d6 =



(Variable)


 r7 = 163.0022
 d7 = 1.5000
 nd4 = 1.77250
 νd4 = 49.60


 r8 = 17.9806
 d8 = 6.9388


 r9 = −95.4021
 d9 = 1.3643
 nd5 = 1.77250
 νd5 = 49.60


r10 = 31.9739
d10 = 3.3248


r11 = −83.4161 (Aspheric)
d11 = 2.2162
 nd6 = 1.68893
 νd6 = 31.07


r12 = −51.8821
d12 = 1.2000
 nd7 = 1.77250
 νd7 = 49.60


r13 = 110.2656
d13 = 0.1500


r14 = 52.7805
d14 = 4.8751
 nd8 = 1.68893
 νd8 = 31.07


r15 = −44.3555
d15 =



(Variable)


r16 = ∞ (Stop)
d16 =



(Variable)


r17 = 20.3453 (Aspheric)
d17 = 4.8644
 nd9 = 1.49700
 νd9 = 81.54


r18 = −18.1397
d18 = 0.1995


r19 = −17.0247
d19 = 0.9865
nd10 = 1.58144
νd10 = 40.75


r20 = −41.9737
d20 =



(Variable)


r21 = −34.7870
d21 = 1.6000
nd11 = 1.84666
νd11 = 23.78


r22 = −15.2340
d22 = 0.9000
nd12 = 1.51633
νd12 = 64.14


r23 = 20.7010
d23 =



(Variable)


r24 = 21.6523
d24 = 1.2000
nd13 = 1.80518
νd13 = 25.42


r25 = 11.8448
d25 = 5.1050
nd14 = 1.49700
νd14 = 81.54


r26 = 282.0413
d26 = 0.1500


r27 = 18.6629
d27 = 5.4207
nd15 = 1.49700
νd15 = 81.54


r28 = −35.6003 (Aspheric)
d28 = 0.1500


r29 = 45.1746
d29 = 1.0526
nd16 = 1.80518
νd16 = 25.42


r30 = 26.6635
d30 =



(Variable)


r31 = ∞
d31 =
nd17 = 1.51633
νd17 = 64.14



16.0000


r32 = ∞
d32 = 1.0000


r33 = ∞
d33 = 2.6000
nd18 = 1.54771
νd18 = 62.84


r34 = ∞
d34 = 1.0000


r35 = ∞
d35 = 0.7500
nd19 = 1.51633
νd19 = 64.14


r36 = ∞
d36 = 1.2400










[0279] Aspherical Coefficients


[0280] 11 th surface


[0281] K=0


[0282] A4=7.1125×10−6


[0283] A6=2.0512×10−8


[0284] A8=−5.1595 ×10−11


[0285] A10=0.0000


[0286] 17 th surface


[0287] K=0


[0288] A4=−1.5184×10−5


[0289] A6=−2.3566×10−8


[0290] A8=3.4360×10−10


[0291] A10=0.0000


[0292] 28 th surface


[0293] K=0


[0294] A4=3.1780×10−5


[0295] A6=−9.9597×10−8


[0296] A8=−5.2192×10−10


[0297] A10=0.0000


[0298] Zooming Data (∞)
10WWSSSTTf (mm)7.2599923.2999774.75182FNO2.80003.57783.5000ω (° )38.5213.194.13d61.0454615.0284631.0988946.1676359.30495d1552.0823729.2179616.445477.468482.50000d1619.8377012.093027.118004.382851.23876d202.855105.906249.1359311.3221515.45881d234.364417.151166.720195.063105.57919d305.494427.401219.5775111.7835310.27488



EXAMPLE 6

[0299]

11
















 r1 = 141.6786
 d1 = 2.6000
 nd1 = 1.84666
 νd1 = 23.78


 r2 = 82.2770
 d2 = 0.2054


 r3 = 86.0098
 d3 = 6.6214
 nd2 = 1.49700
 νd2 = 81.54


 r4 = −623.7275
 d4 = 0.2000


 r5 = 66.9330
 d5 = 4.9709
 nd3 = 1.69680
 νd3 = 55.53


 r6 = 242.1492
 d6 =



(Variable)


 r7 = −1681.4393
 d7 = 1.7000
 nd4 = 1.77250
 νd4 = 49.60


 r8 = 17.8527
 d8 = 8.5980


 r9 = −59.5314 (Aspheric)
 d9 = 0.2000
 nd5 = 1.53508
 νd5 = 40.94


r10 = −119.6362
d10 = 1.3000
 nd6 = 1.77250
 νd6 = 49.60


r11 = 342.3608
d11 = 4.1895


r12 = −24.2842
d12 = 1.1790
 nd7 = 1.48749
 νd7 = 70.23


r13 = −101.8680
d13 = 4.5574
 nd8 = 1.84666
 νd8 = 23.78


r14 = −33.5232
d14 =



(Variable)


r15 = −17.5269
d15 = 1.3000
 nd9 = 1.77250
 νd9 = 49.60


r16 = −20.0488
d16 = 1.0127


r17 = ∞ (Stop)
d17 =



(Variable)


r18 = 21.3027 (Aspheric)
d18 = 5.1829
nd10 = 1.49700
νd10 = 81.54


r19 = −71.1108
d19 = 0.0740


r20 = 64.9416
d20 = 1.1010
nd11 = 1.80610
νd11 = 40.92


r21 = 16.9316
d21 = 5.1171
nd12 = 1.49700
νd12 = 81.54


r22 = −53.3840
d22 =



(Variable)


r23 = −52.6066
d23 = 0.9000
nd13 = 1.51633
νd13 = 64.14


r24 = 13.9038
d24 = 3.2142
nd14 = 1.84666
νd14 = 23.78


r25 = 21.1652
d25 =



(Variable)


r26 = 30.4474 (Aspheric)
d26 = 5.0612
nd15 = 1.49700
νd15 = 81.54


r27 = −27.3044
d27 = 0.1500


r28 = 172.6100
d28 = 4.5076
nd16 = 1.61800
νd16 = 63.33


r29 = −16.2580
d29 = 1.0000
nd17 = 1.84666
νd17 = 23.78


r30 = −61.9158
d30 =



(Variable)


r31 = ∞
d31 =
nd18 = 1.51633
νd18 = 64.14



16.0000


r32 = ∞
d32 = 1.0000


r33 = ∞
d33 = 2.6000
nd19 = 1.54771
νd19 = 62.84


r34 = ∞
d34 = 1.0000


r35 = ∞
d35 = 0.7500
nd20 = 1.51633
νd20 = 64.14


r36 = ∞
d36 = 1.2400


r37 = ∞










[0300] Aspherical Coefficients


[0301] 9 th surface


[0302] K=0


[0303] A4=2.2129×10−5


[0304] A6=6.5725×10−10


[0305] A8=7.2804×10−11


[0306] A10=0.0000


[0307] 18 th surface


[0308] K=0


[0309] A4=−1.8979×10−5


[0310] A6=8.7960×10−9


[0311] A8=−1.5301×10−10


[0312] A10=0.0000


[0313] 26 th surface


[0314] K=0


[0315] A4=−1.7277×10−5


[0316] A6=3.9898×10−9


[0317] A8=−5.5382×10−11


[0318] A10=0.0000


[0319] Zooming Data (∞)
12WWSSSTTf (mm)7.2600213.0000323.3001341.7306974.75304FNO2.80003.40613.50003.50003.5000ω (° )38.4513.034.12d61.6999010.5661129.9568447.1401057.75352d1438.8384618.701639.093724.720002.59257d1725.0005515.7775411.574557.615041.02237d221.491937.8521511.9577016.0334223.12571d258.124068.997106.587945.198265.37687d304.611215.360976.516416.389664.90755



EXAMPLE 7

[0320]

13
















 r1 = 133.2906
 d1 = 2.6000
 nd1 = 1.84666
 νd1 = 23.78


 r2 = 79.7190
 d2 = 0.4683


 r3 = 88.0849
 d3 = 6.7955
 nd2 = 1.49700
 νd2 = 81.54


 r4 = −928.2450
 d4 = 0.2000


 r5 = 61.1424
 d5 = 5.7149
 nd3 = 1.60311
 νd3 = 60.64


 r6 = 290.9980
 d6 =



(Variable)


 r7 = 858.6153
 d7 = 1.7000
 nd4 = 1.77250
 νd4 = 49.60


 r8 = 17.2556
 d8 = 8.7043


 r9 = −65.5194 (Aspheric)
 d9 = 0.2000
 nd5 = 1.53508
 νd5 = 40.94


r10 = −103.0065
d10 = 1.3000
 nd6 = 1.77250
 νd6 = 49.60


r11 = 207.4789
d11 = 3.9972


r12 = −29.5057
d12 = 1.2706
 nd7 = 1.60311
 νd7 = 60.64


r13 = −3.472 × 104
d13 = 4.4191
 nd8 = 1.84666
 νd8 = 23.78


r14 = −39.4285
d14 =



(Variable)


r15 = −14.2222
d15 = 1.3000
 nd9 = 1.77250
 νd9 = 49.60


r16 = −15.6911
d16 = 0.9994


r17 = ∞ (Stop)
d17 =



(Variable)


r18 = 29.1466 (Aspheric)
d18 = 5.3713
nd10 = 1.49700
νd10 = 81.54


r19 = −55.2100
d19 = 0.1000


r20 = −2878.6841
d20 = 1.0357
nd11 = 1.69895
νd11 = 30.13


r21 = 26.7931
d21 = 5.3045
nd12 = 1.61800
νd12 = 63.33


r22 = −52.9610
d22 =



(Variable)


r23 = −72.6679
d23 = 0.9000
nd13 = 1.51633
νd13 = 64.14


r24 = 14.0385
d24 = 3.1899
nd14 = 1.84666
νd14 = 23.78


r25 = 23.1764
d25 =



(Variable)


r26 = 34.1187 (Aspheric)
d26 = 4.0924
nd15 = 1.49700
νd15 = 81.54


r27 = −27.1159
d27 = 0.1500


r28 = −179.2221
d28 = 4.5403
nd16 = 1.61800
νd16 = 63.33


r29 = −13.8901
d29 = 1.0000
nd17 = 1.84666
νd17 = 23.78


r30 = −48.2993
d30 =



(Variable)


r31 = ∞
d31 =
nd18 = 1.51633
νd18 = 64.14



16.0000


r32 = ∞
d32 = 1.0000


r33 = ∞
d33 = 2.6000
nd19 = 1.54771
νd19 = 62.84


r34 = ∞
d34 = 1.0000


r35 = ∞
d35 = 0.7500
nd20 = 1.51633
νd20 = 64.14


r36 = ∞
d36 = 1.2400


r37 = ∞










[0321] Aspherical Coefficients


[0322] 9 th surface


[0323] K=0


[0324] A4=2.2685×10−5


[0325] A6=−9.9328×10−9


[0326] A8=6.5515×10−11


[0327] A10=0.0000


[0328] 18 th surface


[0329] K=0


[0330] A4=−1.5955×10−5


[0331] A6=1.031533 10−8


[0332] A8=−9.0638×10−11


[0333] A10=0.0000


[0334] 26 th surface


[0335] K=0


[0336] A4=−1.7668×10−5


[0337] A6=−1.6378×10−9


[0338] A8=5.8919×10−11


[0339] A10=0.0000


[0340] Zooming Data (∞)
14WWSSSTTf (mm)7.2599412.9997923.2996041.7293574.74958FNO2.80003.27363.50003.50003.5000ω (° )38.4813.034.10d61.5761310.5869329.6608247.2203157.38048d1435.3362414.675757.057283.954472.57253d1727.9022518.4622913.505529.051771.02205d222.012276.5060411.6408016.2232923.37367d257.591117.591117.591117.591117.59111d304.350606.309376.831546.238475.63660



EXAMPLE 8

[0341]

15
















 r1 = 154.0084
 d1 = 2.6000
 nd1 = 1.84666
 νd1 = 23.78


 r2 = 85.1308
 d2 = 0.2000


 r3 = 89.0506
 d3 = 6.8812
 nd2 = 1.49700
 νd2 = 81.54


 r4 = −500.6640
 d4 = 0.2000


 r5 = 71.0865
 d5 = 4.9871
 nd3 = 1.69680
 νd3 = 55.53


 r6 = 321.2628
 d6 =



(Variable)


 r7 = −1661.3349
 d7 = 1.7000
 nd4 = 1.77250
 νd4 = 49.60


 r8 = 18.0950
 d8 = 8.8337


 r9 = −62.2296 (Aspheric)
 d9 = 0.2000
 nd5 = 1.53508
 νd5 = 40.94


r10 = −129.5877
d10 = 1.3000
 nd6 = 1.77250
 νd6 = 49.60


r11 = 1178.5652
d11 = 3.1344


r12 = −33.4282
d12 = 1.1790
 nd7 = 1.48749
 νd7 = 70.23


r13 = 90.9167
d13 = 4.3569
 nd8 = 1.84666
 νd8 = 23.78


r14 = −65.5020
d14 =



(Variable)


r15 = ∞ (Stop)
d15 = 2.6661


r16 = −14.4489
d16 = 0.9955
 nd9 = 1.77250
 νd9 = 49.60


r17 = −16.4057
d17 =



(Variable)


r18 = 29.3239 (Aspheric)
d18 = 5.3050
nd10 = 1.80610
νd10 = 40.74


r19 = 422.7477
d19 = 0.4857


r20 = 93.3084
d20 = 1.0357
nd11 = 1.69895
νd11 = 30.13


r21 = 16.2156
d21 = 5.2656
nd12 = 1.49700
νd12 = 81.54


r22 = −38.2018
d22 =



(Variable)


r23 = −65.0932
d23 = 0.9000
nd13 = 1.51633
νd13 = 64.14


r24 = 13.7958
d24 = 2.9478
nd14 = 1.84666
νd14 = 23.78


r25 = 19.9898
d25 =



(Variable)


r26 = 26.7797 (Aspheric)
d26 = 4.1503
nd15 = 1.49700
νd15 = 81.54


r27 = −33.3863
d27 = 0.1500


r28 = 66.7328
d28 = 4.3835
nd16 = 1.61800
νd16 = 63.33


r29 = −18.3728
d29 = 1.0000
nd17 = 1.80518
νd17 = 25.42


r30 = −118.1096
d30 =



(Variable)


r31 = ∞
d31 =
nd18 = 1.51633
νd18 = 64.14



16.0000


r32 = ∞
d32 = 1.0000


r33 = ∞
d33 = 2.6000
nd19 = 1.54771
νd19 = 62.84


r34 = ∞
d34 = 1.0000


r35 = ∞
d35 = 0.7500
nd20 = 1.51633
νd20 = 64.14


r36 = ∞
d36 = 1.2400


r37 = ∞










[0342] Aspherical Coefficients


[0343] 9 th surface


[0344] K=0


[0345] A4=1.7476×10−5


[0346] A6=1.7656×10−8


[0347] A8=2.5483×10−11


[0348] A10=0.0000


[0349] 18 th surface


[0350] K=0


[0351] A4=−7.2819×10−6


[0352] A6=1.5490×10−8


[0353] A8=−1.0251×10−10


[0354] A10=0.0000


[0355] 26 th surface


[0356] K=0


[0357] A4=−1.2862×10−5


[0358] A6=−1.1215×10−8


[0359] A8=2.6887×10−11


[0360] A10=0.0000


[0361] Zooming Data (∞)
16WWSSSTTf (mm)7.2600013.0000423.3000041.7301074.75000FNO2.80003.24523.50003.50003.5000ω (° )38.4313.044.11d61.5181310.7671729.8451047.3589258.73695d1443.6222120.6789210.311385.776941.73681d1719.3497013.115049.545255.965950.99829d222.581488.8161412.3859315.9652220.93289d258.674907.434405.563585.043385.18729d304.282155.522657.393467.913667.76975



EXAMPLE 9

[0362]

17
















 r1 = 125.4804
 d1 = 2.6000
 nd1 = 1.84666
 νd1 = 23.78


 r2 = 73.9280
 d2 = 0.6131


 r3 = 82.0053
 d3 = 7.1121
 nd2 = 1.49700
 νd2 = 81.54


 r4 = −2731.9228
 d4 = 0.2000


 r5 = 73.7403
 d5 = 6.0707
 nd3 = 1.69680
 νd3 = 55.53


 r6 = 689.0297
 d6 =



(Variable)


 r7 = 327.5056
 d7 = 1.7000
 nd4 = 1.77250
 νd4 = 49.60


 r8 = 14.2610
 d8 = 8.5253


 r9 = −89.4120
 d9 = 1.3000
 nd5 = 1.77250
 νd5 = 49.60


r10 = 38.2328
d10 = 0.2000
 nd6 = 1.53508
 νd6 = 40.94


r11 = 28.4986 (Aspheric)
d11 = 2.5230


r12 = 47.5033
d12 = 1.1790
 nd7 = 1.48749
 νd7 = 70.23


r13 = 34.1694
d13 = 3.2934
 nd8 = 1.84666
 νd8 = 23.78


r14 = −324.6493
d14 =



(Variable)


r15 = ∞ (Stop)
d15 =



(Variable)


r16 = 16.9572 (Aspheric)
d16 = 7.2692
 nd9 = 1.49700
 νd9 = 81.54


r17 = 452.6400
d17 = 0.1000


r18 = 136.4678
d18 = 1.1010
nd10 = 1.80610
νd10 = 40.92


r19 = 15.7221
d19 = 5.6961
nd11 = 1.49700
νd11 = 81.54


r20 = −38.5697
d20 =



(Variable)


r21 = 58.4853
d21 = 3.0175
nd12 = 1.84666
νd12 = 23.78


r22 = −202.3168
d22 = 1.4952
nd13 = 1.51633
νd13 = 64.14


r23 = 15.1757
d23 = 8.9786


r24 = −49.4262 (Aspheric)
d24 = 5.1311
nd14 = 1.49700
νd14 = 81.54


r25 = −19.2986
d25 = 0.1500


r26 = 18.4543
d26 = 5.9364
nd15 = 1.61800
νd15 = 63.33


r27 = −38.6487
d27 = 1.0000
nd16 = 1.84666
νd16 = 23.78


r28 = 76.9096
d28 =



(Variable)


r29 = ∞
d29 =
nd17 = 1.51633
νd17 = 64.14



16.0000


r30 = ∞
d30 = 1.0000


r31 = ∞
d31 = 2.6000
nd18 = 1.54771
νd18 = 62.84


r32 = ∞
d32 = 1.0000


r33 = ∞
d33 = 0.7500
nd19 = 1.51633
νd19 = 64.14


r34 = ∞
d34 = 1.2400


r35 = ∞










[0363] Aspherical Coefficients


[0364] 11 th surface


[0365] K=0


[0366] A4=−2.9080×10−5


[0367] A6=−4.7003×10−8


[0368] A8=1.3039×10−11


[0369] A10=0.0000


[0370] 16 th surface


[0371] K=0


[0372] A4=−2.6940×10−5


[0373] A6=−2.6991×10−8


[0374] A8=−4.1850×10−11


[0375] A10=0.0000


[0376] 24 th surface


[0377] K=0


[0378] A4=4.8837×10−6


[0379] A6=4.0251×10−8


[0380] A8=5.0375×10−10


[0381] A10=0.0000


[0382] Zooming Data (∞)
18WWSSSTTf (mm)7.2601013.0001023.3000041.7293974.74571FNO2.80003.23113.50003.50003.5000ω (° )38.4312.964.12d41.2238210.5752130.8611247.1725560.33060d1444.4162922.3976112.107355.550002.52402d1518.029449.251346.752303.909331.06282d201.563096.2630910.1879514.9460918.74913



EXAMPLE 10

[0383]

19
















 r1 = 127.5747
 d1 = 2.6000
 nd1 = 1.84666
 νd1 = 23.78


 r2 = 76.5681
 d2 = 0.6108


 r3 = 87.0503
 d3 = 6.7061
 nd2 = 1.49700
 νd2 = 81.54


 r4 = −906.1216
 d4 = 0.2000


 r5 = 65.5756
 d5 = 5.1656
 nd3 = 1.69680
 νd3 = 55.53


 r6 = 257.9868
 d6 =



(Variable)


 r7 = −841.7430
 d7 = 1.7000
 nd4 = 1.77250
 νd4 = 49.60


 r8 = 20.7672
 d8 = 0.1181
 nd5 = 1.53508
 νd5 = 40.94


 r9 = 17.4318 (Aspheric)
 d9 = 8.3674


r10 = −69.0347
d10 = 1.3000
 nd6 = 1.77250
 νd6 = 49.60


r11 = 50.8067
d11 = 3.5790


r12 = −34.9364
d12 = 1.2000
 nd7 = 1.48749
 νd7 = 70.23


r13 = −206.9525
d13 = 0.7359


r14 = 131.5379
d14 = 2.9312
 nd8 = 1.68893
 νd8 = 31.07


r15 = −65.1273
d15 = 0.2838


r16 = 446.1597
d16 = 3.4504
 nd9 = 1.84666
 νd9 = 23.78


r17 = −111.5214
d17 =



(Variable)


r18 = −89.0223
d18 = 1.2751
nd10 = 1.73400
νd10 = 51.47


r19 = −5156.0079
d19 = 1.0546


r20 = ∞ (Stop)
d20 =



(Variable)


r21 = 20.4978 (Aspheric)
d21 = 5.4824
nd11 = 1.49700
νd11 = 81.54


r22 = −55.0155
d22 = 0.4103


r23 = 42.1503
d23 = 1.1010
nd12 = 1.80610
νd12 = 40.92


r24 = 14.0853
d24 = 5.1806
nd13 = 1.49700
νd13 = 81.54


r25 = −75.3872
d25 =



(Variable)


r26 = −29.7893
d26 = 0.9000
nd14 = 1.51633
νd14 = 64.14


r27 = 14.3985
d27 = 3.2881
nd15 = 1.84666
νd15 = 23.78


r28 = 28.0747
d28 =



(Variable)


r29 = 117.1492 (Aspheric)
d29 = 4.3053
nd16 = 1.49700
νd16 = 81.54


r30 = −21.7875
d30 = 0.1500


r31 = 78.2931
d31 = 5.0168
nd17 = 1.61800
νd17 = 63.33


r32 = −14.1145
d32 = 1.0000
nd18 = 1.84666
νd18 = 23.78


r33 = −50.2289
d33 =



(Variable)


r34 = ∞
d34 =
nd19 = 1.51633
νd19 = 64.14



16.0000


r35 = ∞
d35 = 1.0000


r36 = ∞
d36 = 2.6000
nd20 = 1.54771
νd20 = 62.84


r37 = ∞
d37 = 1.0000


r38 = ∞
d38 = 0.7500
nd21 = 1.51633
νd21 = 64.14


r39 = ∞
d39 = 1.2400


r40 = ∞










[0384] Aspherical Coefficients


[0385] 9 th surface


[0386] K=0


[0387] A4=−1.8060×10−5


[0388] A6=−1.5653×10−8


[0389] A8=−3.1402×10−10


[0390] A10=0.0000


[0391] 21 th surface


[0392] K=0


[0393] A4=−1.9350×10−5


[0394] A6=8.1535×10−9


[0395] A8=−1.1537×10−10


[0396] A10=0.0000


[0397] 29 th surface


[0398] K=0


[0399] A4=−1.4723×10−5


[0400] A6=−4.3194×10−9


[0401] A8=1.8719×10−10


[0402] A10=0.0000


[0403] Zooming Data (∞)
20WWSSSTTf (mm)7.2600013.0000023.3000841.7305974.75291FNO2.80003.45123.50003.50003.5000ω (° )38.4812.854.11d61.6478710.5888330.0482247.1187058.44456d1744.7217422.7941811.481175.950853.03382d2018.9146411.567778.331115.339471.07479d251.848978.0314311.9578316.1382022.70498d288.282648.782146.880405.854835.87377d334.710295.375206.587196.424034.10299



EXAMPLE 11

[0404]

21
















 r1 = 89.8312
 d1 = 2.6000
 nd1 = 1.84666
 νd1 = 23.78


 r2 = 63.9685
 d2 = 0.0006


 r3 = 64.1053
 d3 = 9.1675
 nd2 = 1.49700
 νd2 = 81.54


 r4 = 479.8472
 d4 = 0.2000


 r5 = 75.2405
 d5 = 6.4325
 nd3 = 1.60311
 νd3 = 60.64


 r6 = 342.9922
 d6 =



(Variable)


 r7 = 959.9708
 d7 = 1.8000
 nd4 = 1.81600
 νd4 = 46.62


 r8 = 18.8418
 d8 = 5.3800


 r9 = −472.5238
 d9 = 1.1000
 nd5 = 1.73400
 νd5 = 51.47


r10 = 28.9390
d10 = 5.9081


r11 = −29.2098
d11 = 1.2000
 nd6 = 1.71300
 νd6 = 53.87


r12 = 100.5460
d12 = 0.1500


r13 = 49.3222
d13 = 7.5695
 nd7 = 1.63980
 νd7 = 34.46


r14 = −24.6810 (Aspheric)
d14 =



(Variable)


r15 = 1133.4292
d15 = 1.2000
 nd8 = 1.78472
 νd8 = 25.68


r16 = 106.5968
d16 = 0.2500


r17 = ∞ (Stop)
d17 =



(Variable)


r18 = 20.1552 (Aspheric)
d18 = 5.1000
 nd9 = 1.49700
 νd9 = 81.54


r19 = −94.7419
d19 = 0.1774


r20 = 36.0051
d20 = 1.1410
nd10 = 1.80440
νd10 = 39.59


r21 = 13.5064
d21 = 5.5328
nd11 = 1.60311
νd11 = 30.64


r22 = −1129.4923
d22 =



(Variable)


r23 = −72.5596
d23 = 0.9000
nd12 = 1.51633
νd12 = 64.14


r24 = 11.8049
d24 = 2.9338
nd13 = 1.84666
νd13 = 23.78


r25 = 16.8009
d25 =



(Variable)


r26 = 91.9126
d26 = 2.9663
nd14 = 1.49700
νd14 = 81.54


r27 = −29.0231 (Aspheric)
d27 = 0.1500


r28 = 48.8627
d28 = 5.1022
nd15 = 1.60311
νd15 = 60.64


r29 = −13.3197
d29 = 0.8500
nd16 = 1.84666
νd16 = 23.78


r30 = −48.0006
d30 =



(Variable)


r31 = ∞
d31 =
nd17 = 1.51633
νd17 = 64.14



16.0000


r32 = ∞
d32 = 1.0000


r33 = ∞
d33 = 2.6000
nd18 = 1.54771
νd18 = 62.84


r34 = ∞
d34 = 1.0000


r35 = ∞
d35 = 0.7500
nd19 = 1.51633
νd19 = 64.14


r36 = ∞
d36 = 1.2400


r37 = ∞










[0405] Aspherical Coefficients


[0406] 14 th surface


[0407] K=0


[0408] A4=−8.9550×10−9


[0409] A6=8.4748×10−9


[0410] A8=1.6761×10−11


[0411] A10=0.0000


[0412] 18 th surface


[0413] K=0


[0414] A4=−1.7592×10−5


[0415] A6=4.4455×10−9


[0416] A8=−1.3451×10−10


[0417] A10=0.0000


[0418] 27 th surface


[0419] K=0


[0420] A4=−1.4716×10−6


[0421] A6=1.5442×10−9


[0422] A8=−2.3629×10−10


[0423] A10=0.0000


[0424] Zooming Data (∞)
22WWSSSTTf (mm)7.3384513.1032123.2894038.8914574.68837FNO2.80003.18593.50003.50003.5000ω (° )38.1213.014.08d61.3600612.6403031.0748248.1796461.33273d1454.2637025.0469311.104995.198241.70314d1717.4169812.142108.862146.815381.02608d221.500004.149806.858039.3403916.90092d256.856407.478956.179725.743526.81559d304.460207.592298.383109.824685.35600



EXAMPLE 12

[0425]

23
















 r1 = 82.2399
 d1 = 2.6000
 nd1 = 1.84666
 νd1 = 23.78


 r2 = 60.0259
 d2 = 0.1000


 r3 = 60.6829
 d3 = 7.7500
 nd2 = 1.49700
 νd2 = 81.54


 r4 = 307.4605
 d4 = 0.2000


 r5 = 72.7643
 d5 = 5.8500
 nd3 = 1.60311
 νd3 = 60.64


 r6 = 328.6935
 d6 =



(Variable)


 r7 = 266.6699
 d7 = 1.8000
 nd4 = 1.81600
 νd4 = 46.62


 r8 = 18.3068
 d8 = 6.0269


 r9 = −91.9091
 d9 = 1.1000
 nd5 = 1.73400
 νd5 = 51.47


r10 = 31.9296
d10 = 5.1735


r11 = −33.4696 (Aspheric)
d11 = 1.2000
 nd6 = 1.71300
 νd6 = 53.87


r12 = 1.387 × 104
d12 = 0.1500


r13 = 76.1645
d13 = 6.2143
 nd7 = 1.69895
 νd7 = 30.13


r14 = −29.0944
d14 =



(Variable)


r15 = −256.8086
d15 = 1.0000
 nd8 = 1.78472
 νd8 = 25.68


r16 = 217.7610
d16 = 0.2030


r17 = ∞ (Stop)
d17 =



(Variable)


r18 = 19.3410 (Aspheric)
d18 = 5.5508
 nd9 = 1.49700
 νd9 = 81.54


r19 = −61.9647
d19 = 0.1774


r20 = 28.8671
d20 = 1.1410
nd10 = 1.80440
νd10 = 39.59


r21 = 13.5945
d21 = 5.8000
nd11 = 1.49700
νd11 = 81.54


r22 = 5392.6719
d22 =



(Variable)


r23 = −154.6780
d23 = 0.9000
nd12 = 1.51633
νd12 = 64.14


r24 = 11.7076
d24 = 3.6031
nd13 = 1.84666
νd13 = 23.78


r25 = 15.0847
d25 =



(Variable)


r26 = 50.4757
d26 = 3.2775
nd14 = 1.49700
νd14 = 81.54


r27 = −50.8313 (Aspheric)
d27 = 0.1500


r28 = 45.8348
d28 = 5.5505
nd15 = 1.60311
νd15 = 60.64


r29 = −13.2011
d29 = 0.8500
nd16 = 1.84666
νd16 = 23.78


r30 = −38.4178
d30 =



(Variable)


r31 = ∞
d31 =
nd17 = 1.51633
νd17 = 64.14



16.0000


r32 = ∞
d32 = 1.0000


r33 = ∞
d33 = 2.6000
nd18 = 1.54771
νd18 = 62.84


r34 = ∞
d34 = 1.0000


r35 = ∞
d35 = 0.7500
nd19 = 1.51633
νd19 = 64.14


r36 = ∞
d36 = 1.2400


r37 = ∞










[0426] Aspherical Coefficients


[0427] 11 th surface


[0428] K=0


[0429] A4=2.1955×10−6


[0430] A6=7.9776×10−10


[0431] A8=4.2465×10−12


[0432] A10=0.0000


[0433] 18 th surface


[0434] K=0


[0435] A4=−2.2173×10−5


[0436] A6=−5.2442×10−10


[0437] A8=−1.3172×10−10


[0438] A10=0.0000


[0439] 27 th surface


[0440] K=0


[0441] A4=−4.3385×10−6


[0442] A6=−5.8507×10−9


[0443] A8=−3.8312×10−10


[0444] A10=0.0000


[0445] Zooming Data (∞)
24WWSSSTTf (mm)7.3525313.1415523.3004440.5897074.68803FNO2.80003.19433.50003.50003.5000ω (° )38.0913.064.10d61.3600612.8824531.0049549.0568759.99418d1452.4057325.2992611.478015.292111.70314d1717.4744512.092159.078296.896881.02608d221.500003.822436.290798.7222016.22424d256.188796.989005.582235.342605.88322d301.191557.724215.356009.527203.22100



EXAMPLE 13

[0446]

25
















 r1 = 128.1845
 d1 = 2.6000
 nd1 = 1.84666
 νd1 = 23.78


 r2 = 77.8836
 d2 = 0.1422


 r3 = 79.5351
 d3 = 8.7726
 nd2 = 1.60311
 νd2 = 60.64


 r4 = 1.760 × 105
 d4 = 0.2000


 r5 = 60.5207
 d5 = 7.8199
 nd3 = 1.49700
 νd3 = 81.54


 r6 = 225.3888
 d6 =



(Variable)


 r7 = 87.0813
 d7 = 1.5000
 nd4 = 1.77250
 νd4 = 49.60


 r8 = 15.7852
 d8 = 8.9335


 r9 = −28.4093
 d9 = 1.3643
 nd5 = 1.77250
 νd5 = 49.60


r10 = 61.5066
d10 = 2.4804


r11 = −48.6469 (Aspheric)
d11 = 0.2000
 nd6 = 1.53508
 νd6 = 40.94


r12 = −200.0000
d12 = 1.2000
 nd7 = 1.69350
 νd7 = 53.20


r13 = 96.2114
d13 = 0.2000


r14 = 68.6685
d14 = 6.7199
 nd8 = 1.68893
 νd8 = 31.07


r15 = −32.7420
d15 =



(Variable)


r16 = ∞ (Stop)
d16 = 0.4000


r17 = 312.4731
d17 = 0.9972
 nd9 = 1.60342
 νd9 = 38.03


r18 = −144.3938
d18 =



(Variable)


r19 = 18.9253 (Aspheric)
d19 = 3.6985
nd10 = 1.49700
νd10 = 81.54


r20 = −1.054 × 107
d20 = 0.1774


r21 = 58.8544
d21 = 1.1208
nd11 = 1.77250
νd11 = 49.60


r22 = 15.9897
d22 = 4.9136
nd12 = 1.49700
νd12 = 81.54


r23 = −68.6413
d23 =



(Variable)


r24 = −73.7867
d24 = 0.9000
nd13 = 1.51633
νd13 = 64.14


r25 = 17.0943
d25 = 1.8262
nd14 = 1.84666
νd14 = 23.78


r26 = 22.4714
d26 =



(Variable)


r27 = 37.0884 (Aspheric)
d27 = 4.8733
nd15 = 1.49700
νd15 = 81.54


r28 = −23.1086
d28 = 0.1500


r29 = −909.2556
d29 = 3.3951
nd16 = 1.49700
νd16 = 81.54


r30 = −18.5310
d30 = 1.0265
nd17 = 1.84666
νd17 = 23.78


r31 = −50.0749
d31 =



(Variable)


r32 = ∞
d32 =
nd18 = 1.51633
νd18 = 64.14



16.0000


r33 = ∞
d33 = 1.0000


r34 = ∞
d34 = 2.6000
nd19 = 1.54771
νd19 = 62.84


r35 = ∞
d35 = 1.0000


r36 = ∞
d36 = 0.7500
nd20 = 1.51633
νd20 = 64.14


r37 = ∞
d37 = 1.2400


r38 = ∞










[0447] Aspherical Coefficients


[0448] 11 th surface


[0449] K=0


[0450] A4=9.2934×10−6


[0451] A6=−4.3005×10−9


[0452] A8=−6.0577×10−11


[0453] A10=0.0000


[0454] 19 th surface


[0455] K=0


[0456] A4=−1.5515×10−5


[0457] A6=−1.5901×10−9


[0458] A8=−1.9683×10−10


[0459] A10=0.0000


[0460] 27 th surface


[0461] K=0


[0462] A4=−1.7557×10−5


[0463] A6=−2.2661×10−9


[0464] A8=1.2023×10−10


[0465] A10=0.0000


[0466] Zooming Data (∞)
26WWSSSTTf (mm)7.2769913.1348323.3015641.8583874.69868FNO2.80003.00963.50003.50003.5000ω (° )38.4713.074.13d61.0000012.3246329.1205747.1425558.02772d156.7204327.0053213.693087.482552.50000d1820.3844313.6855410.296747.226031.55935d230.867343.003626.203808.9125714.79711d267.498198.313945.779535.094995.49059d315.531909.1381611.986708.6359212.42630



EXAMPLE 14

[0467]

27
















 r1 = 117.1093
 d1 = 2.6000
 nd1 = 1.84666
 νd1 = 23.78


 r2 = 78.9815
 d2 = 0.2900


 r3 = 83.6308
 d3 = 7.1360
 nd2 = 1.49700
 νd2 = 81.54


 r4 = 8.136 × 104
 d4 = 0.2000


 r5 = 64.0026
 d5 = 7.2854
 nd3 = 1.49700
 νd3 = 81.54


 r6 = 406.9074
 d6 =



(Variable)


 r7 = 173.0596
 d7 = 1.5000
 nd4 = 1.77250
 νd4 = 49.60


 r8 = 14.7807
 d8 = 8.6963


 r9 = −33.4479
 d9 = 1.3643
 nd5 = 1.77250
 νd5 = 49.60


r10 = 82.7642
d10 = 1.5769


r11 = −78.1187 (Aspheric)
d11 = 0.4088
 nd6 = 1.66680
 νd6 = 33.05


r12 = 518.9177
d12 = 1.2000
 nd7 = 1.69350
 νd7 = 53.20


r13 = 55.8817
d13 = 0.0065


r14 = 43.1420
d14 = 5.9081
 nd8 = 1.68893
 νd8 = 31.07


r15 = −31.8050
d15 =



(Variable)


r16 = ∞ (Stop)
d16 =



(Variable)


r17 = 21.9025 (Aspheric)
d17 = 3.3063
 nd9 = 1.49700
 νd9 = 81.54


r18 = −1.082 × 106
d18 = 0.2991


r19 = 30.2359
d19 = 1.1208
nd10 = 1.77250
νd10 = 49.60


r20 = 14.9061
d20 = 5.0481
nd11 = 1.49700
νd11 = 81.54


r21 = −81.9434
d21 =



(Variable)


r22 = −101.2030
d22 = 0.9000
nd12 = 1.51633
νd12 = 64.14


r23 = 15.4168
d23 = 1.8234
nd13 = 1.84666
νd13 = 23.78


r24 = 20.2251
d24 =



(Variable)


r25 = 42.9650 (Aspheric)
d25 = 4.1635
nd14 = 1.49700
νd14 = 81.54


r26 = −21.2353
d26 = 0.1500


r27 = −231.8094
d27 = 2.6973
nd15 = 1.49700
νd15 = 81.54


r28 = −16.2244
d28 = 1.2276
nd16 = 1.84666
νd16 = 23.78


r29 = −47.0800
d29 =



(Variable)


r30 = ∞
d30 =
nd17 = 1.51633
νd17 = 64.14



16.0000


r31 = ∞
d31 = 1.0000


r32 = ∞
d32 = 2.6000
nd18 = 1.54771
νd18 = 62.84


r33 = ∞
d33 = 1.0000


r34 = ∞
d34 = 0.7500
nd19 = 1.51633
νd19 = 64.14


r35 = ∞
d35 = 1.2400


r36 = ∞










[0468] Aspherical Coefficients


[0469] 11 th surface


[0470] K=0


[0471] A4=8.8203×10−6


[0472] A6=9.5199×10−9


[0473] A8=−4.6923×10−11


[0474] A10=0.0000


[0475] 17 th surface


[0476] K=0


[0477] A4=−1.2806×10−5


[0478] A6=−2.1296×10−9


[0479] A8=−2.5132×10−11


[0480] A10=0.0000


[0481] 25 th surface


[0482] K=0


[0483] A4=−1.7844×10−5


[0484] A6=8.4598×10−10


[0485] A8=1.3070×10−10


[0486] A10=0.0000


[0487] Zooming Data (∞)
28WWSSSTTf (mm)7.3366813.2473723.3007842.1381574.69414FNO2.80003.09023.50003.50003.5000ω (° )38.2713.004.12d61.0000011.4212430.9406148.2903959.30210d1555.5966225.8569213.753656.563392.50000d1620.1877214.5307511.358447.512831.55935d212.764264.806247.1571110.1640416.30729d247.718567.833896.047204.979054.27440d294.705608.3110010.793208.5697413.14420



EXAMPLE 15

[0488]

29
















 r1 = 132.6548
 d1 = 2.6000
 nd1 = 1.84666
 νd1 = 23.78


 r2 = 79.4364
 d2 = 0.4361


 r3 = 85.8501
 d3 = 6.6634
 nd2 = 1.60311
 νd2 = 60.64


 r4 = 4.060 × 104
 d4 = 0.2000


 r5 = 59.6705
 d5 = 6.1756
 nd3 = 1.49700
 νd3 = 81.54


 r6 = 294.2591
 d6 =



(Variable)


 r7 = 98.7402
 d7 = 1.5000
 nd4 = 1.77250
 νd4 = 49.60


 r8 = 14.8930
 d8 = 9.4296


 r9 = −32.3971
 d9 = 1.3643
 nd5 = 1.77250
 νd5 = 49.60


r10 = 70.8620
d10 = 2.0091


r11 = −72.3210 (Aspheric)
d11 = 0.2000
 nd6 = 1.53508
 νd6 = 40.94


r12 = −200.0000
d12 = 1.2000
 nd7 = 1.69350
 νd7 = 53.20


r13 = 67.0853
d13 = 0.2000


r14 = 44.8428
d14 = 6.9613
 nd8 = 1.68893
 νd8 = 31.07


r15 = −35.6841
d15 =



(Variable)


r16 = ∞ (Stop)
d16 =



(Variable)


r17 = 21.0081 (Aspheric)
d17 = 2.9255
 nd9 = 1.49700
 νd9 = 81.54


r18 = −9.840 × 105
d18 = 0.1774


r19 = 34.1654
d19 = 1.1208
nd10 = 1.77250
νd10 = 49.60


r20 = 14.0687
d20 = 4.9352
nd11 = 1.49700
νd11 = 81.54


r21 = −74.9646
d21 =



(Variable)


r22 = −61.8007
d22 = 0.9000
nd12 = 1.51633
νd12 = 64.14


r23 = 16.0108
d23 = 1.8375
nd13 = 1.84666
νd13 = 23.78


r24 = 22.5570
d24 =



(Variable)


r25 = 32.5943 (Aspheric)
d25 = 4.3313
nd14 = 1.49700
νd14 = 81.54


r26 = −33.8655
d26 = 0.1500


r27 = 53.1963
d27 = 1.1524
nd15 = 1.84666
νd15 = 23.78


r28 = 18.3125
d28 = 3.6734
nd16 = 1.49700
νd16 = 81.54


r29 = −121.7913
d29 =



(Variable)


r30 = ∞
d30 =
nd17 = 1.51633
νd17 = 64.14



16.0000


r31 = ∞
d31 = 1.0000


r32 = ∞
d32 = 2.6000
nd18 = 1.54771
νd18 = 62.84


r33 = ∞
d33 = 1.0000


r34 = ∞
d34 = 0.7500
nd19 = 1.51633
νd19 = 64.14


r35 = ∞
d35 = 1.2400


r36 = ∞










[0489] Aspherical Coefficients


[0490] 11 th surface


[0491] K=0


[0492] A4=5.6253×10−6


[0493] A6=8.1204×10−9


[0494] A8=−1.5465×10−10


[0495] A10=0.0000


[0496] 17 th surface


[0497] K=0


[0498] A4=−1.0911×10−5


[0499] A6=−8.6347×10−10


[0500] A8=−3.2657×10−11


[0501] A10=0.0000


[0502] 25 th surface


[0503] K=0


[0504] A4=−1.8333×10−5


[0505] A6=−3.1998×10−9


[0506] A8=1.0415×10−10


[0507] A10=0.0000


[0508] Zooming Data (∞)
30WWSSSTTf (mm)7.2863813.0918323.2994241.5511074.69787FNO2.80003.09333.50003.50003.5000ω (° )38.4113.044.13d61.0000012.0168729.5289147.0979958.40761d1556.6022727.2510213.504697.099692.50000d1620.2094614.0992710.842987.369031.55935d212.229754.071456.738469.2992814.66227d248.057398.703386.543606.015916.08811d296.194209.2233012.553308.6063914.38620



EXAMPLE 16

[0509]

31
















 r1 = 80.0460
 d1 = 2.6000
 nd1 = 1.84666
 νd1 = 23.78


 r2 = 57.3690
 d2 = 0.0798


 r3 = 56.8758
 d3 = 6.9751
 nd2 = 1.49700
 νd2 = 81.54


 r4 = 362.0517
 d4 = 0.2000


 r5 = 73.3775
 d5 = 4.4654
 nd3 = 1.60311
 νd3 = 60.64


 r6 = 289.7112
 d6 =



(Variable)


 r7 = 177.0825
 d7 = 1.5000
 nd4 = 1.77250
 νd4 = 49.60


 r8 = 16.8427
 d8 = 7.9000


 r9 = −29.2679 (Aspheric)
 d9 = 1.3643
 nd5 = 1.77250
 νd5 = 49.60


r10 = 67.6142
d10 = 3.5642


r11 = 117.8157
d11 = 4.8943
 nd6 = 1.72825
 νd6 = 28.46


r12 = −31.3298
d12 = 0.5000


r13 = −63.4774
d13 = 1.0000
 nd7 = 1.74400
 νd7 = 44.78


r14 = −239.8825
d14 =



(Variable)


r15 = −435.4231
d15 = 1.2680
 nd8 = 1.72825
 νd8 = 28.46


r16 = 514.6994
d16 = 1.3139


r17 = ∞ (Stop)
d17 =



(Variable)


r18 = 20.0387 (Aspheric)
d18 = 5.6776
 nd9 = 1.49700
 νd9 = 81.54


r19 = −73.1240
d19 = 0.1774


r20 = 46.3298
d20 = 1.1410
nd10 = 1.80440
νd10 = 39.59


r21 = 13.8759
d21 = 5.4223
nd11 = 1.60311
νd11 = 60.64


r22 = −120.0020
d22 =



(Variable)


r23 = −55.7471
d23 = 0.9000
nd12 = 1.51633
νd12 = 64.14


r24 = 11.2108
d24 = 1.8651
nd13 = 1.84666
νd13 = 23.78


r25 = 15.9872
d25 =



(Variable)


r26 = 55.1052
d26 = 2.9459
nd14 = 1.49700
νd14 = 81.54


r27 = −28.6459 (Aspheric)
d27 = 0.1500


r28 = 69.1964
d28 = 4.5501
nd15 = 1.60311
νd15 = 60.64


r29 = −13.8791
d29 = 1.0000
nd16 = 1.84666
νd16 = 23.78


r30 = −46.4615
d30 =



(Variable)


r31 = ∞
d31 =
nd17 = 1.51633
νd17 = 64.14



16.0000


r32 = ∞
d32 = 1.0000


r33 = ∞
d33 = 2.6000
nd18 = 1.54771
νd18 = 62.84


r34 = ∞
d34 = 1.0000


r35 = ∞
d35 = 0.7500
nd19 = 1.51633
νd19 = 64.14


r36 = ∞
d36 = 1.2400


r37 = ∞










[0510] Aspherical Coefficients


[0511] 9 th surface


[0512] K=0


[0513] A4=8.8395×10−6


[0514] A6=5.0711×10−9


[0515] A8=−1.9545×10−11


[0516] A10=0.0000


[0517] 18 th surface


[0518] K=0


[0519] A4=−2.0678×10−5


[0520] A6=−6.4243×10−9


[0521] A8=2.3028×10−11


[0522] A10=0.0000


[0523] 27 th surface


[0524] K=0


[0525] A4=−3.0971×10−6


[0526] A6=−9.4407×10−9


[0527] A8=1.9644×10−11


[0528] A10=0.0000


[0529] Zooming Data (∞)
32WSTf (mm)7.2718523.2974974.69992FNO2.80003.50003.5000ω (° )40.1713.974.40d61.3600630.1291258.31748d1454.7045612.246251.70314d1717.263019.523911.02608d221.500006.5358516.09191d257.857996.358246.81641d304.640008.846007.32400



EXAMPLE 17

[0530]

33
















 r1 = 84.5614
 d1 = 2.6000
 nd1 = 1.84666
 νd1 = 23.78


 r2 = 60.9235
 d2 = 0.1000


 r3 = 60.9993
 d3 = 7.7500
 nd2 = 1.49700
 νd2 = 81.54


 r4 = 411.3180
 d4 = 0.2000


 r5 = 69.8137
 d5 = 5.8500
 nd3 = 1.60311
 νd3 = 60.64


 r6 = 273.9185
 d6 =



(Variable)


 r7 = 326.8029
 d7 = 1.8000
 nd4 = 1.81600
 νd4 = 46.62


 r8 = 18.4614
 d8 = 5.8823


 r9 = −86.8945
 d9 = 1.1000
 nd5 = 1.73400
 νd5 = 51.47


r10 = 32.9914
d10 = 5.2210


r11 = −30.1936 (Aspheric)
d11 = 1.2000
 nd6 = 1.71300
 νd6 = 53.87


r12 = 3.111 × 104
d12 = 0.1500


r13 = 94.9186
d13 = 6.1767
 nd7 = 1.69895
 νd7 = 30.13


r14 = −27.0373
d14 =



(Variable)


r15 = −754.3167
d15 = 0.8000
 nd8 = 1.78472
 νd8 = 25.68


r16 = 50.7584
d16 = 2.0000
 nd9 = 1.68893
 νd9 = 31.07


r17 = 699.9122
d17 = 0.7000


r18 = ∞ (Stop)
d18 =



(Variable)


r19 = 19.3389 (Aspheric)
d19 = 5.5976
nd10 = 1.49700
νd10 = 81.54


r20 = −64.3089
d20 = 0.1774


r21 = 36.8090
d21 = 1.1410
nd11 = 1.80440
νd11 = 39.59


r22 = 15.7560
d22 = 4.3000
nd12 = 1.49700
νd12 = 81.54


r23 = 6909.3107
d23 =



(Variable)


r24 = −213.9678
d24 = 0.9000
nd13 = 1.51633
νd13 = 64.14


r25 = 11.9504
d25 = 3.6757
nd14 = 1.84666
νd14 = 23.78


r26 = 15.7330
d26 =



(Variable)


r27 = 56.9085
d27 = 3.2663
nd15 = 1.49700
νd15 = 81.54


r28 = −49.9335 (Aspheric)
d28 = 0.1500


r29 = 48.3454
d29 = 5.3103
nd16 = 1.60311
νd16 = 60.64


r30 = −12.9112
d30 = 0.8500
nd17 = 1.84666
νd17 = 23.78


r31 = −36.0617
d31 =



(Variable)


r32 = ∞
d32 =
nd18 = 1.51633
νd18 = 64.14



16.0000


r33 = ∞
d33 = 1.0000


r34 = ∞
d34 = 2.6000
nd19 = 1.54771
νd19 = 62.84


r35 = ∞
d35 = 1.0000


r36 = ∞
d36 = 0.7500
nd20 = 1.51633
νd20 = 64.14


r37 = ∞
d37 = 1.2400


r38 = ∞










[0531] Aspherical Coefficients


[0532] 11 th surface


[0533] K=0


[0534] A4=3.5442×10−6


[0535] A6=−1.0145×10−8


[0536] A8=4.1292×10−11


[0537] A10=0.0000


[0538] 19 th surface


[0539] K=0


[0540] A4=−2.3122×10−5


[0541] A6=−1.0925×10−9


[0542] A8=−1.2640×10−10


[0543] A10=0.0000


[0544] 28 th surface


[0545] K=0


[0546] A4=−2.8818×10−6


[0547] A6=−5.4227×10−9


[0548] A8=−2.8339×10−10


[0549] A10=0.0000


[0550] Zooming Data (∞)
34WSTf (mm)7.2721223.2991574.69940FNO2.80003.50003.5000ω (° )38.4413.064.09d61.3600631.2364559.54246d1452.3223111.303841.70314d1817.202758.822961.02608d231.500006.6171016.48589d266.174855.371426.39230d312.400006.464003.36900



EXAMPLE 18

[0551]

35
















 r1 = 85.6717
 d1 = 2.6000
 nd1 = 1.84666
 νd1 = 23.78


 r2 = 61.4682
 d2 = 0.1000


 r3 = 61.7093
 d3 = 7.7500
 nd2 = 1.49700
 νd2 = 81.54


 r4 = 391.3879
 d4 = 0.2000


 r5 = 71.8120
 d5 = 5.8500
 nd3 = 1.60311
 νd3 = 60.64


 r6 = 318.2499
 d6 =



(Variable)


 r7 = 360.3572
 d7 = 1.8000
 nd4 = 1.81600
 νd4 = 46.62


 r8 = 18.8770
 d8 = 5.9565


 r9 = −91.8447
 d9 = 1.1000
 nd5 = 1.73400
 νd5 = 51.47


r10 = 33.5783
d10 = 5.2551


r11 = −31.3548 (Aspheric)
d11 = 1.2000
 nd6 = 1.71300
 νd6 = 53.87


r12 = 4.805 × 104
d12 = 0.1500


r13 = 97.5840
d13 = 6.2516
 nd7 = 1.69895
 νd7 = 30.13


r14 = −27.8035
d14 =



(Variable)


r15 = ∞
d15 = 1.8000
 nd8 = 1.78472
 νd8 = 25.68


r16 = 268.7641 (Aspheric)
d16 = 1.0000


r17 = ∞ (Stop)
d17 =



(Variable)


r18 = 18.6304 (Aspheric)
d18 = 5.6253
 nd9 = 1.49700
 νd9 = 81.54


r19 = −57.6238
d19 = 0.1774


r20 = 34.9774
d20 = 1.1410
nd10 = 1.80440
νd10 = 39.59


r21 = 14.9385
d21 = 4.3000
nd11 = 1.49700
νd11 = 81.54


r22 = 4295.3319
d22 =



(Variable)


r23 = −226.3830
d23 = 0.9000
nd12 = 1.51633
νd12 = 64.14


r24 = 11.9132
d24 = 3.6481
nd13 = 1.84666
νd13 = 23.78


r25 = 15.2759
d25 =



(Variable)


r26 = 54.3162
d26 = 3.3130
nd14 = 1.49700
νd14 = 81.54


r27 = −51.5747 (Aspheric)
d27 = 0.1500


r28 = 49.4131
d28 = 5.2625
nd15 = 1.60311
νd15 = 60.64


r29 = −13.1129
d29 = 0.8500
nd16 = 1.84666
νd16 = 23.78


r30 = −36.5139
d30 =



(Variable)


r31 = ∞
d31 =
nd17 = 1.51633
νd17 = 64.14



16.0000


r32 = ∞
d32 = 1.0000


r33 = ∞
d33 = 2.6000
nd18 = 1.54771
νd18 = 62.84


r34 = ∞
d34 = 1.0000


r35 = ∞
d35 = 0.7500
nd19 = 1.51633
νd19 = 64.14


r36 = ∞
d36 = 1.2400


r37 = ∞










[0552] Aspherical Coefficients


[0553] 11 th surface


[0554] K=0


[0555] A4=3.5400×10−6


[0556] A6=−7.6377×10−9


[0557] A8=4.0209×10−11


[0558] A10=0.0000


[0559] 16 th surface


[0560] K=0


[0561] A4=−4.0343×10−7


[0562] A6=2.7672×10−8


[0563] A8=−2.5380×10−10


[0564] A10=0.0000


[0565] 18 th surface


[0566] K=0


[0567] A4=−2.6388×10−5


[0568] A6=−1.7329×10−9


[0569] A8=−1.6305×10−10


[0570] A10=0.0000


[0571] 27 th surface


[0572] K=0


[0573] A4=−3.4938×10−6


[0574] A6=−5.9935×10−9


[0575] A8=−2.8356×10−10


[0576] A10=0.0000


[0577] Zooming Data (∞)
36WSTf (mm)7.2724423.3003274.70039FNO2.80003.50003.5000ω (° )38.4513.054.09d61.3600631.1540359.61613d1452.2899811.328341.70314d1717.277948.929191.02608d221.500006.4491216.47111d256.184895.464326.07561d302.397006.509003.82700



EXAMPLE 19

[0578]

37
















 r1 = 102.8951
 d1 = 2.2000
 nd1 = 1.84666
 νd1 = 23.78


 r2 = 61.5389
 d2 =
 nd2 = 1.49700
 νd2 = 81.54



11.0000


 r3 = −641.2805
 d3 = 0.2750


 r4 = 51.4180
 d4 = 6.1875
 nd3 = 1.69680
 νd3 = 55.53


 r5 = 146.6226
 d5 =



(Variable)


 r6 = 148.7220
 d6 = 1.9010
 nd4 = 1.83400
 νd4 = 37.16


 r7 = 15.1960
 d7 = 8.2500


 r8 = −17.1556
 d8 = 1.6500
 nd5 = 1.80610
 νd5 = 40.92


 r9 = 15.0399 (Aspheric)
 d9 = 2.0625


r10 = 58.8129
d10 = 3.4375
 nd6 = 1.68893
 νd6 = 31.07


r11 = −74.3150
d11 = 0.2062


r12 = 241.0544
d12 = 4.8125
 nd7 = 1.68893
 νd7 = 31.07


r13 = −21.3830
d13 =



(Variable)


r14 ∞ (Stop)
d14 =



(Variable)


r15 = 37.4279 (Aspheric)
d15 = 3.4375
 nd8 = 1.49700
 νd8 = 81.54


r16 = −462.8778
d16 = 0.2062


r17 = 15.8702
d17 = 5.5000
 nd9 = 1.59551
 νd9 = 39.24


r18 = 79.4628
d18 = 1.3750
nd10 = 1.80610
νd10 = 40.92


r19 = 14.4884
d19 =



(Variable)


r20 = 26.6553
d20 = 4.1250
nd11 = 1.83400
νd11 = 37.16


r21 = 147.2888
d21 = 0.4125


r22 = 142.7176
d22 = 1.3750
nd12 = 1.84666
νd12 = 23.78


r23 = 17.8989
d23 = 6.1875
nd13 = 1.49700
νd13 = 81.54


r24 = −22.9886 (Aspheric)
d24 =



(Variable)


r25 = ∞
d25 =
nd14 = 1.51633
νd14 = 64.14



23.3750


r26 = ∞
d26 = 1.3750


r27 = ∞
d27 = 2.2000
nd15 = 1.54771
νd15 = 62.84


r28 = ∞
d28 = 1.3750


r29 = ∞
d29 = 1.0313
nd16 = 1.52300
νd16 = 55.00


r30 = ∞
d30 = 3.2468


r31 = ∞










[0579] Aspherical Coefficients


[0580] 9 th surface


[0581] K=0


[0582] A4=−1.4335×10−4


[0583] A6=3.6008×10−7


[0584] A8=−1.5707×10−9


[0585] A10=0.0000


[0586] 15 th surface


[0587] K=0


[0588] A4=−8.3514×10−6


[0589] A6=−6.4776×10−10


[0590] A8=−1.3217×10−11


[0591] A10=0.0000


[0592] 24 th surface


[0593] K=0


[0594] A4=2.1082×10−5


[0595] A6=9.2526×10−8


[0596] A8=−1.4509×10−9


[0597] A10=6.8600×10−12


[0598] Zooming Data (∞)
38WSTf (mm)7.1543618.8367250.05002FNO2.04822.35362.5012ω (° )38.3815.786.16d51.3750023.1002444.56543d1353.6260519.093896.13762d1423.1950910.317873.56923d197.0058012.7088218.49477d241.198217.554509.33878



EXAMPLE 20

[0599]

39
















 r1 = 155.9824
 d1 = 1.7875
 nd1 = 1.84666
 νd1 = 23.78


 r2 = 61.8424
 d2 =
 nd2 = 1.61800
 νd2 = 63.33



11.0000


 r3 = −600.9530
 d3 = 0.2750


 r4 = 47.5178
 d4 = 6.1875
 nd3 = 1.69680
 νd3 = 55.53


 r5 = 121.5999
 d5 =



(Variable)


 r6 = 119.2914
 d6 = 1.3750
 nd4 = 1.80610
 νd4 = 40.92


 r7 = 13.2227 (Aspheric)
 d7 = 8.2500


 r8 = −32.4710
 d8 = 1.6500
 nd5 = 1.83400
 νd5 = 37.16


 r9 = 39.0123
 d9 = 1.3750


r10 = 165.6443
d10 = 1.3750
 nd6 = 1.57501
 νd6 = 41.50


r11 = 20.0406
d11 = 7.1500
 nd7 = 1.75520
 νd7 = 27.51


r12 = −48.8507
d12 =



(Variable)


r13 = ∞ (Stop)
d13 =



(Variable)


r14 = 30.8548
d14 = 3.4375
 nd8 = 1.80518
 νd8 = 25.42


r15 = −89.0085
d15 = 0.2062


r16 = 38.9337 (Aspheric)
d16 = 4.4000
 nd9 = 1.80610
 νd9 = 40.92


r17 = −94.3851
d17 = 1.3750
nd10 = 1.84666
νd10 = 23.78


r18 = 32.5308
d18 =



(Variable)


r19 = −57.6645
d19 = 2.7500
nd11 = 1.77250
νd11 = 49.60


r20 = −47.1601
d20 = 1.3750
nd12 = 1.60342
νd12 = 38.03


r21 = 30.6668
d21 =



(Variable)


r22 = −228.3337
d22 = 1.3750
nd13 = 1.84666
νd13 = 23.78


r23 = 19.0716
d23 = 6.1875
nd14 = 1.49700
νd14 = 81.54


r24 = −31.2823 (Aspheric)
d24 = 0.2062


r25 = 36.1622
d25 = 6.1875
nd15 = 1.69350
νd15 = 53.21


r26 = −35.8359
d26 =



(Variable)


r27 = ∞
d27 =
nd16 = 1.51633
νd16 = 64.14



23.3750


r28 = ∞
d28 = 1.3750


r29 = ∞
d29 = 2.2000
nd17 = 1.54771
νd17 = 62.84


r30 = ∞
d30 = 1.3750


r31 = ∞
d31 = 1.0313
nd18 = 1.52300
νd18 = 55.00


r32 = ∞
d32 = 3.2377


r33 = ∞










[0600] Aspherical Coefficients


[0601] 7 th surface


[0602] K=0


[0603] A4=−2.0811×10−5


[0604] A6=−9.3584×10−10


[0605] A8=−9.2039×10−10


[0606] A10=0.0000


[0607] 16 th surface


[0608] K=0


[0609] A4=−9.0277×10−6


[0610] A6=2.1013×10−8


[0611] A8=−5.4554×10−10


[0612] A10=2.6012×10−12


[0613] 24 th surface


[0614] K=0


[0615] A4=−1.8657×10−6


[0616] A6=2.3003×10−8


[0617] A8=−5.0119×10−10


[0618] A10=0.0000


[0619] Zooming Data (∞)
40WSTf (mm)7.1620618.8363150.04733FNO2.02902.36732.8226ω (° )38.3415.986.16d51.3750020.3927942.36136d1249.9878014.959687.89768d1320.7415012.472664.81483d182.756925.6140410.58915d217.737725.383516.87877d262.750009.9048011.70852



EXAMPLE 21

[0620]

41
















 r1 = 104.3405
 d1 = 2.2000
 nd1 = 1.84666
 νd1 = 23.78


 r2 = 59.5725
 d2 =
 nd2 = 1.49700
 νd2 = 81.54



11.0000


 r3 = −1321.3547
 d3 = 0.2750


 r4 = 47.5960
 d4 = 6.1875
 nd3 = 1.69680
 νd3 = 55.53


 r5 = 136.8909
 d5 =



(Variable)


 r6 = 140.6680
 d6 = 1.9010
 nd4 = 1.80610
 νd4 = 40.92


 r7 = 13.7491 (Aspheric)
 d7 = 6.1875


 r8 = −60.0958
 d8 = 1.6500
 nd5 = 1.83400
 νd5 = 37.16


 r9 = 61.9207
 d9 = 4.1250


r10 = −21.5206
d10 = 1.3750
 nd6 = 1.63930
 νd6 = 44.87


r11 = 56.5075
d11 = 3.4375


r12 = 96.6074
d12 = 5.5000
 nd7 = 1.80100
 νd7 = 34.97


r13 = −25.9673
d13 =



(Variable)


r14 = ∞ (Stop)
d14 = 2.7500


r15 = −40.0734
d15 = 1.2375
 nd8 = 1.60311
 νd8 = 60.64


r16 = −78.4453
d16 =



(Variable)


r17 = 34.7554
d17 = 4.8125
 nd9 = 1.80809
 νd9 = 22.76


r18 = 1028.4306
d18 = 0.2062


r19 = 60.9355 (Aspheric)
d19 = 4.4000
nd10 = 1.80610
νd10 = 40.92


r20 = −29.1117
d20 = 1.3750
nd11 = 1.84666
νd11 = 23.78


r21 = 127.3373
d21 =



(Variable)


r22 = 32.2756
d22 = 2.7500
nd12 = 1.60342
νd12 = 38.03


r23 = 145.1897
d23 = 1.3750
nd13 = 1.77250
νd13 = 49.60


r24 = 16.7202
d24 =



(Variable)


r25 = 33.5170
d25 = 7.5625
nd14 = 1.49700
νd14 = 81.54


r26 = −27.9038 (Aspheric)
d26 = 0.2062


r27 = 69.1174
d27 = 1.3750
nd15 = 1.84666
νd15 = 23.78


r28 = 19.6221
d28 = 6.1875
nd16 = 1.49700
νd16 = 81.54


r29 = −57.6668
d29 =



(Variable)


r30 = ∞
d30 =
nd17 = 1.51633
νd17 = 64.14



23.3750


r31 = ∞
d31 = 1.3750


r32 = ∞
d32 = 2.2000
nd18 = 1.54771
νd18 = 62.84


r33 = ∞
d33 = 1.3750


r34 = ∞
d34 = 1.0313
nd19 = 1.52300
νd19 = 55.00


r35 = ∞
d35 = 3.2477


r36 = ∞










[0621] Aspherical Coefficients


[0622] 7 th surface


[0623] K=0


[0624] A4=−9.7269×10−6


[0625] A6=−1.1309×10−7


[0626] A8=6.4969×10−10


[0627] A10=0.0000


[0628] 19 th surface


[0629] K=0


[0630] A4=−7.1713×10−6


[0631] A6=−1.9289×10−9


[0632] A8=−3.9414×10−11


[0633] A10=2.4197×10−13


[0634] 26 th surface


[0635] K=0


[0636] A4=−5.4190×10−7


[0637] A6=−2.7019×10−8


[0638] A8=−3.8924×10−11


[0639] A10=0.0000


[0640] Zooming Data (∞)
42WSTf (mm)7.1457118.8552250.04974FNO2.00472.36612.8509ω (° )38.4415.986.16d51.3750021.9458342.47373d1350.6575414.254865.45806d1621.3352012.382235.88901d212.747315.1878110.57000d247.029077.050196.86418d292.750009.0105010.53508



EXAMPLE 22

[0641]

43
















 r1 = 131.8770
 d1 = 2.6000
 nd1 = 1.84666
 νd1 = 23.78


 r2 = 77.6142
 d2 = 0.2000


 r3 = 80.8510
 d3 = 6.3796
 nd2 = 1.49700
 νd2 = 81.54


 r4 = −2977.8302
 d4 = 0.2000


 r5 = 67.0321
 d5 = 5.0727
 nd3 = 1.69680
 νd3 = 55.53


 r6 = 266.3144
 d6 =



(Variable)


 r7 = 1181.5043
 d7 = 1.7000
 nd4 = 1.77250
 νd4 = 49.60


 r8 = 17.1175
 d8 = 8.6482


 r9 = −77.8867 (Aspheric)
 d9 = 0.2000
 nd5 = 1.53508
 νd5 = 40.94


r10 = −246.1158
d10 = 1.3000
 nd6 = 1.77250
 νd6 = 49.60


r11 = 430.0786
d11 = 4.1745


r12 = −24.0715
d12 = 1.1790
 nd7 = 1.48749
 νd7 = 70.23


r13 = −346.5320
d13 = 4.4844
 nd8 = 1.84666
 νd8 = 23.78


r14 = −42.2965
d14 =



(Variable)


r15 = −13.2198
d15 = 1.3000
 nd9 = 1.77250
 νd9 = 49.60


r16 = −14.9920
d16 = 1.0969


r17 = ∞ (Stop)
d17 =



(Variable)


r18 = 23.9865 (Aspheric)
d18 = 5.3859
nd10 = 1.49700
νd10 = 81.54


r19 = −62.7302
d19 = 0.4217


r20 = 65.9532
d20 = 1.1010
nd11 = 1.80610
νd11 = 40.92


r21 = 18.5852
d21 = 5.1465
nd12 = 1.49700
νd12 = 81.54


r22 = −44.8828
d22 =



(Variable)


r23 = −97.1974
d23 = 0.9000
nd13 = 1.51633
νd13 = 64.14


r24 = 13.4425
d24 = 3.0840
nd14 = 1.84666
νd14 = 23.78


r25 = 18.2242
d25 =



(Variable)


r26 = 22.8739 (Aspheric)
d26 = 4.4524
nd15 = 1.49700
νd15 = 81.54


r27 = −32.9476
d27 = 0.1500


r28 = 111.9927
d28 = 3.9237
nd16 = 1.61800
νd16 = 63.33


r29 = −19.6931
d29 = 1.0000
nd17 = 1.84666
νd17 = 23.78


r30 = −150.1546
d30 =



(Variable)


r31 = ∞
d31 =
nd18 = 1.51633
νd18 = 64.14



16.0000


r32 = ∞
d32 = 1.0000


r33 = ∞
d33 = 2.6000
nd19 = 1.54771
νd19 = 62.84


r34 = ∞
d34 = 1.0000


r35 = ∞
d35 = 0.7500
nd20 = 1.51633
νd20 = 64.14


r36 = ∞
d36 = 1.2400


r37 = ∞










[0642] Aspherical Coefficients


[0643] 9 th surface


[0644] K=0


[0645] A4=2.1755×10−5


[0646] A6=7.8908×10−8


[0647] A8=−3.9978×10−10


[0648] A10=1.3455×10−12


[0649] 18 th surface


[0650] K=0


[0651] A4=−1.6485×10−5


[0652] A6=1.0262×10−8


[0653] A8=−3.9805×10−10


[0654] A10=3.5368×10−12


[0655] 26 th surface


[0656] K=0


[0657] A4=−1.4825×10−5


[0658] A6=−5.9281×10−8


[0659] A8=7.7542×10−10


[0660] A10=−4.4522×10−12


[0661] Zooming Data (∞)
44WWSSSTTf (mm)7.2599412.9998123.2996241.7290974.74765FNO2.80003.36893.50003.50003.5000ω (° )38.5013.164.16d61.6141710.6486230.7740047.2320558.71613d1444.7052923.2632713.317556.201752.00079d1717.5450410.444177.818325.521781.09606d221.500007.8298112.5154016.7404422.56134d2510.8240110.719847.991235.552244.75986d304.547905.423126.092006.602495.99969



EXAMPLE 23

[0662]

45
















 r1 = 120.4727
 d1 = 2.6000
 nd1 = 1.84666
 νd1 = 23.78


 r2 = 73.3708
 d2 = 0.2000


 r3 = 76.1454
 d3 = 6.5370
 nd2 = 1.49700
 νd2 = 81.54


 r4 = 2489.4366
 d4 = 0.2000


 r5 = 67.2263
 d5 = 5.1710
 nd3 = 1.69680
 νd3 = 55.53


 r6 = 274.6988
 d6 =



(Variable)


 r7 = 714.7087
 d7 = 1.7000
 nd4 = 1.77250
 νd4 = 49.60


 r8 = 16.1327
 d8 = 8.7770


 r9 = −81.5087 (Aspheric)
 d9 = 1.5000
 nd5 = 1.69350
 νd5 = 53.20


r10 = −1305.7058
d10 = 4.0368


r11 = −20.2734
d11 = 1.1790
 nd6 = 1.48749
 νd6 = 70.23


r12 = −62.9405
d12 = 4.8993
 nd7 = 1.84666
 νd7 = 23.78


r13 = −30.8273
d13 =



(Variable)


r14 = 15.4268
d14 = 1.3000
 nd8 = 1.77250
 νd8 = 49.60


r15 = −18.4448
d15 = 1.1025


r16 = ∞ (Stop)
d16 =



(Variable)


r17 = 25.1535 (Aspheric)
d17 = 5.5136
 nd9 = 1.49700
 νd9 = 81.54


r18 = −55.2846
d18 = 1.5487


r19 = 64.5304
d19 = 1.1010
nd10 = 1.80610
νd10 = 40.92


r20 = 18.9507
d20 = 5.1163
nd11 = 1.49700
νd11 = 81.54


r21 = −43.1776
d21 =



(Variable)


r22 = −77.9341
d22 = 0.9000
nd12 = 1.51633
νd12 = 64.14


r23 = 13.4277
d23 = 3.4850
nd13 = 1.84666
νd13 = 23.78


r24 = 17.9962
d24 =



(Variable)


r25 = 21.5792 (Aspheric)
d25 = 4.5936
nd14 = 1.49700
νd14 = 81.54


r26 = −34.1855
d26 = 0.1500


r27 = 300.7621
d27 = 4.4791
nd15 = 1.61800
νd15 = 63.33


r28 = −17.4341
d28 = 1.0000
nd16 = 1.84666
νd16 = 23.78


r29 = −75.6852
d29 =



(Variable)


r30 = ∞
d30 =
nd17 = 1.51633
νd17 = 64.14



16.0000


r31 = ∞
d31 = 1.0000


r32 = ∞
d32 = 2.6000
nd18 = 1.54771
νd18 = 62.84


r33 = ∞
d33 = 1.0000


r34 = ∞
d34 = 0.7500
nd19 = 1.51633
νd19 = 64.14


r35 = ∞
d35 = 1.2400


r36 = ∞










[0663] Aspherical Coefficients


[0664] 9 th surface


[0665] K=0


[0666] A4=1.8629×10−5


[0667] A6=6.9168×10−8


[0668] A8=−2.7327×10−10


[0669] A10=1.2121×10−12


[0670] 17 th surface


[0671] K=0


[0672] A4=−1.6089×10−5


[0673] A6=−2.0073×10−8


[0674] A8=3.8142×10−10


[0675] A10=−2.1082×10−12


[0676] 25 th surface


[0677] K=0


[0678] A4=−1.5463×10−5


[0679] A6=−2.6231×10−8


[0680] A8=2.4043×10−10


[0681] A10=−9.6547×10−13


[0682] Zooming Data (∞)
46WSTf (mm)7.2598223.2991074.74396FNO2.80003.50003.5000ω (° )40.4114.084.46d61.5962731.9764559.22440d1344.7569212.185992.03777d1617.395648.625461.04694d211.5806211.2933521.65579d249.558376.833004.68713d294.666096.448925.81086



EXAMPLE 24

[0683]

47
















 r1 = 128.7222
 d1 = 2.6000
 nd1 = 1.84666
 νd1 = 23.78


 r2 = 76.5762
 d2 = 0.1990


 r3 = 79.6940
 d3 = 6.4626
 nd2 = 1.49700
 νd2 = 81.54


 r4 = −2955.9452
 d4 = 0.2000


 r5 = 67.1272
 d5 = 5.0669
 nd3 = 1.69680
 νd3 = 55.53


 r6 = 263.8928
 d6 =



(Variable)


 r7 = 380.2582
 d7 = 1.7000
 nd4 = 1.77250
 νd4 = 49.60


 r8 = 15.9616
 d8 = 8.7181


 r9 = −59.9828
 d9 = 1.5000
 nd5 = 1.69350
 νd5 = 53.20


r10 = −301.9443 (Aspheric)
d10 = 3.8167


r11 = −20.5627
d11 = 1.1790
 nd6 = 1.48749
 νd6 = 70.23


r12 = −59.0207
d12 = 5.1126
 nd7 = 1.84666
 νd7 = 23.78


r13 = −30.2745
d13 =



(Variable)


r14 = −15.4364
d14 = 1.3000
 nd8 = 1.77250
 νd8 = 49.60


r15 = −18.6107
d15 = 1.1009


r16 = ∞ (Stop)
d16 =



(Variable)


r17 = 25.8357 (Aspheric)
d17 = 5.4824
 nd9 = 1.49700
 νd9 = 81.54


r18 = −58.3524
d18 = 1.9683


r19 = 67.3450
d19 = 1.1010
nd10 = 1.80610
νd10 = 40.92


r20 = 19.5738
d20 = 5.1220
nd11 = 1.49700
νd11 = 81.54


r21 = −40.5031
d21 =



(Variable)


r22 = −94.9007
d22 = 0.9000
nd12 = 1.51633
νd12 = 64.14


r23 = 13.4666
d23 = 3.4715
nd13 = 1.84666
νd13 = 23.78


r24 = 17.9806
d24 =



(Variable)


r25 = 20.7610 (Aspheric)
d25 = 4.5646
nd14 = 1.49700
νd14 = 81.54


r26 = −34.2142
d26 = 0.1500


r27 = 513.7109
d27 = 4.4703
nd15 = 1.61800
νd15 = 63.33


r28 = −17.8110
d28 = 1.0000
nd16 = 1.84666
νd16 = 23.78


r29 = −83.6823
d29 =



(Variable)


r30 = ∞
d30 =
nd17 = 1.51633
νd17 = 64.14



16.0000


r31 = ∞
d31 = 1.0000


r32 = ∞
d32 = 2.6000
nd18 = 1.54771
νd18 = 62.84


r33 = ∞
d33 = 1.0000


r34 = ∞
d34 = 0.7500
nd19 = 1.51633
νd19 = 64.14


r35 = ∞
d35 = 1.2400


r36 = ∞










[0684] Aspherical Coefficients


[0685] 10 th surface


[0686] K=0


[0687] A4=−1.7426×10−5


[0688] A6=−6.5228×10−8


[0689] A8=2.7392×10−10


[0690] A10=−7.9412×10−13


[0691] 17 th surface


[0692] K=0


[0693] A4=−1.6148×10−5


[0694] A6=6.2346×10−9


[0695] A8=−1.2987×10−10


[0696] A10=1.1435×10−12


[0697] 25 th surface


[0698] K=0


[0699] A4=−1.7043×10−5


[0700] A6=−3.2560×10−9


[0701] A8=2.8184×10−10


[0702] A10=−1.6473×10−12


[0703] Zooming Data (∞)
48WSTf (mm)7.2599923.3000574.75174FNO2.80003.50003.5000ω (° )38.4613.174.17d61.6076732.0485559.57895d1344.7113412.275592.02865d1617.181538.385261.03922d211.5000011.4173921.29066d249.893556.807454.59258d294.610286.575266.26289



EXAMPLE 25

[0704]

49
















 r1 = 125.0583
 d1 = 2.6000
 nd1 = 1.84666
 νd1 = 23.78


 r2 = 75.8265
 d2 = 0.2052


 r3 = 78.8734
 d3 = 6.6854
 nd2 = 1.49700
 νd2 = 81.54


 r4 = −1567.5318
 d4 = 0.2000


 r5 = 66.2728
 d5 = 5.0118
 nd3 = 1.69680
 νd3 = 55.53


 r6 = 235.6712
 d6 =



(Variable)


 r7 = 304.4445
 d7 = 1.7000
 nd4 = 1.77250
 νd4 = 49.60


 r8 = 16.9298
 d8 = 8.3012


 r9 = −67.4212
 d9 = 1.5000
 nd5 = 1.77250
 νd5 = 49.60


r10 = 58.4741
d10 = 4.0559


r11 = −33.1641
d11 = 1.1790
 nd6 = 1.48749
 νd6 = 70.23


r12 = 123.4460
d12 = 4.7343
 nd7 = 1.68893
 νd7 = 31.07


r13 = −32.8044 (Aspheric)
d13 =



(Variable)


r14 = −13.3788
d14 = 1.3000
 nd8 = 1.77250
 νd8 = 49.60


r15 = −14.1982
d15 = 0.9997


r16 = ∞ (Stop)
d16 =



(Variable)


r17 = 21.1913 (Aspheric)
d17 = 5.3343
 nd9 = 1.49700
 νd9 = 81.54


r18 = −53.8005
d18 = 0.3147


r19 = 53.6050
d19 = 1.1010
nd10 = 1.80610
νd10 = 40.92


r20 = 16.0840
d20 = 5.1135
nd11 = 1.49700
νd11 = 81.54


r21 = −142.9938
d21 =



(Variable)


r22 = −42.8783
d22 = 0.9000
nd12 = 1.51633
νd12 = 64.14


r23 = 13.9697
d23 = 3.3288
nd13 = 1.84666
νd13 = 23.78


r24 = 21.2945
d24 =



(Variable)


r25 = 31.1501 (Aspheric)
d25 = 4.3266
nd14 = 1.49700
νd14 = 81.54


r26 = −23.5905
d26 = 0.1500


r27 = 911.4978
d27 = 4.2792
nd15 = 1.61800
νd15 = 63.33


r28 = −15.3539
d28 = 1.0000
nd16 = 1.84666
νd16 = 23.78


r29 = −50.5690
d29 =



(Variable)


r30 = ∞
d30 =
nd17 = 1.51633
νd17 = 64.14



16.0000


r31 = ∞
d31 = 1.0000


r32 = ∞
d32 = 2.6000
nd18 = 1.54771
νd18 = 62.84


r33 = ∞
d33 = 1.0000


r34 = ∞
d34 = 0.7500
nd19 = 1.51633
νd19 = 64.14


r35 = ∞
d35 = 1.2400


r36 = ∞










[0705] Aspherical Coefficients


[0706] 13 th surface


[0707] K=0


[0708] A4=−7.0043×10−6


[0709] A6=−5.4249×10−9


[0710] A8=3.0262×10−12


[0711] A10=0.0000


[0712] 17 th surface


[0713] K=0


[0714] A4=−1.8414×10−5


[0715] A6=−1.4788×10−8


[0716] A8=5.9114×10−11


[0717] A10=0.0000


[0718] 25 th surface


[0719] K=0


[0720] A4=−2.1192×10−5


[0721] A6=−1.3690×10−8


[0722] A8=1.3573×10−10


[0723] A10=0.0000


[0724] Zooming Data (∞)
50WSTf (mm)2.80003.50003.5000FNO7.2600123.2999774.74863ω (° )38.3713.004.12d61.7154230.1429158.15917d1344.9007212.400342.55088d1619.058598.366330.99888d211.5000012.2120022.72088d248.150116.363825.19171d294.659956.426504.45718


[0725] FIGS. 26 to 50 are aberration diagrams for Examples 1 to 25 upon focused on an object point at infinity. In these diagrams, SA, AS, DT and CC stand for spherical aberrations, astigmatisms, distortions and chromatic aberrations of magnification at the wide-angle end (a), the intermediate state (b) and the telephoto end of the system, respectively, with “FLY” representing an image height.


[0726] Enumerated below the values of conditions (1) to (14) in the respective examples.
51ConditionEx. 1Ex. 2Ex. 3Ex. 4Ex. 5(1)9.3039.5499.7189.6909.615(2)0.02800.02800.0280−0.0019−0.0019(3)5.1045.0975.1725.3025.296(4)−0.331−0.122−0.068−0.171−0.175(5)0.5810.5700.5570.5940.610(6)10.29610.29610.29610.29610.296(7)−0.287−0.288−0.269−0.285−0.281(8)0.0580.1820.1510.068−0.039(9)0.0100.0850.1590.2350.257(10)1.6371.3491.4651.7241.691(11)0.3060.069−0.139−0.618−0.545(12)2.8462.8462.8912.8462.956(13)2.8002.8002.8002.8002.800(14)2.9843.2063.1243.0603.066ConditionEx. 6Ex. 7Ex. 8Ex. 9Ex. 10(1)9.2579.3469.3119.1239.260(2)0.02800.02800.02800.02800.0280(3)5.0965.0735.2025.3735.163(4)−0.366−0.508−0.366−0.750−0.362(5)0.5920.5660.6100.6430.610(6)10.29710.29610.29610.29510.297(7)−0.274−0.297−0.275−0.326−0.257(8)0.0750.2640.0340.5240.143(9)0.0150.0570.1900.315−0.034(10)1.7442.0591.6682.2801.622(11)0.223−0.1170.0000.274(12)2.8342.7982.7892.4752.848(13)2.8002.8002.8002.8002.800(14)2.9402.9823.0032.8393.014ConditionEx. 11Ex. 12Ex. 13Ex. 14Ex. 15(1)9.9789.8879.75410.1429.704(2)0.02800.02800.02800.02800.0280(3)5.4525.3305.1845.3005.219(4)−0.138−0.156−0.052−0.096−0.061(5)0.5910.5760.5470.5020.539(6)10.17810.15810.26510.19110.252(7)−0.255−0.261−0.334−0.315−0.306(8)0.1770.2530.1870.3020.187(9)0.0550.1230.3660.4550.439(10)1.4781.4951.7111.6851.696(11)−0.078−0.157−0.444−0.454−0.566(12)2.7842.3342.9542.8183.041(13)2.8002.8002.8002.8002.800(14)3.2253.1223.2893.0302.986ConditionEx. 16Ex. 17Ex. 18Ex. 19Ex. 20(1)9.1109.5959.7077.4657.644(2)0.02800.02800.02800.02800.0051(3)4.8275.2895.2963.9273.727(4)−0.075−0.149−0.1530.0900.026(5)0.5420.6030.5890.7040.584(6)10.27310.27210.2726.9966.988(7)−0.286−0.270−0.264−0.294−0.346(8)0.1490.2350.2380.0450.606(9)0.1650.0600.0880.4150.562(10)1.3761.4701.4811.7841.448(11)−0.139−0.108−0.120−0.736(12)2.8342.5252.5253.4543.665(13)2.8002.8002.8002.0482.029(14)2.8173.1033.1223.0782.989ConditionEx. 21Ex. 22Ex. 23Ex. 24Ex. 25(1)7.4099.4488.7809.3919.275(2)0.02800.02800.02800.02800.0280(3)3.7365.1914.8845.2705.131(4)0.091−0.337−0.349−0.358−0.333(5)0.6560.5780.5960.6050.585(6)7.00410.29610.29610.29610.296(7)−0.490−0.291−0.281−0.280−0.301(8)−0.1020.0770.0450.0560.054(9)0.5040.0880.0700.102−0.011(10)1.4041.4951.3861.4671.642(11)−0.6930.4190.3160.3320.287(12)3.6752.8262.8422.8342.841(13)2.0052.8002.8002.8002.800(14)3.0852.9672.7482.9222.938


[0727] It is here noted that the resin layer provided on such lens elements as exemplified above is not in itself regarded as any lens element.


[0728] While various examples corresponding to the respective embodiments of the present invention have been given, it is appreciated that many other modifications thereto may be feasible without departing the scope of the invention described herein.


[0729] For instance, the second lens group G2 in each example may be composed of, in order from its object side, a negative lens element, a negative lens element, a negative lens element, a positive lens element and a positive lens element, as shown in FIG. 10.


[0730] The best arrangement for the third through sixth lens groups G3 through G6 is composed of six lens elements as shown in FIG. 19, or ten lens elements as shown in FIG. 19. Of course, it is noted that the number of lens elements in the rear lens groups, too, may be varied in the scope disclosed herein. For instance, it is possible to replace the positive single lens element on the object side of the fourth lens group G4 shown in FIG. 17 by a doublet lens component obtained by cementing together a positive lens element and a negative lens element; that is, it is possible to construct the third through sixth lens groups with 11 lens elements.


[0731] In what follows, the diagonal length L of the effective image pickup surface and the pixel interval a are now explained. FIG. 51 is illustrative of one exemplary pixel matrix for a given image pickup device. R (red), G (green) and B (blue) pixels are arranged in a mosaic pattern at a pixel interval a. By the term “effective image pickup surface” is intended an area within a photoelectric conversion surface on an image pickup device used for the reproduction of a phototaken image (e.g., for displaying an image on a personal computer or outputting an image to a printer). The effective image pickup surface is set at an area narrower than the overall photoelectric conversion surface of the image pickup device in correspondence to the performance of an optical system (an image circle wherein the performance of the optical system can be assured). The diagonal length L of the effective image pickup surface used herein is understood to mean the diagonal length of this effective image pickup surface. While the image pickup range used for image reproduction may be optionally varied, it is noted that when the zoom lens of the present invention is used for an image pickup device having such functions, there is a change in the diagonal length L of the effective image pickup surface thereof. In such a case, the diagonal length L of the effective image pickup surface according to the present invention is defined by the maximum value in the range allowed for L.


[0732]
FIG. 52 is illustrative of the diagonal length of an effective image pickup surface in the case where a phototaking film is used instead of the image pickup device. When an image is formed on the phototaking film, the effective phototaking area is determined by the aperture of a viewing frame located just in front of the film surface. In this case, too, the shape of the viewing frame may be optionally varied. As in the case of FIG. 51, the diagonal length L of the effective phototaking surface according to the present invention is defined by the maximum value in the range allowed for L.


[0733] The inventive electronic image pickup device as explained above may be applied to phototaking devices wherein object images are formed through a zoom lens and then received on an image pickup device such as a CCD or a silver-salt film, especially digital cameras, video cameras, information processors represented by personal computers, telephone sets, convenient-to-carry portable telephones, etc., as typically explained below.


[0734] How the inventive zoom lens is incorporated in a phototaking optical system 41 of a digital camera is conceptually illustrated in FIGS. 53 through 55. FIG. 53 is a front perspective view of the outside shape of a digital camera 40, and FIG. 54 is a rear perspective view of the same. FIG. 55 is a sectional view illustrative of the construction of the digital camera 40. In this embodiment, the digital camera 40 comprises a phototaking optical system 41 having a phototaking optical path 42, a finder optical system 43 having a finder optical path 44, a shutter 45, a flash 46, a liquid crystal monitor 47, etc. As the shutter 45 attached onto the camera 40 is pressed down, an image is phototaken through the phototaking optical system 41 comprising the inventive zoom lens (roughly illustrated), e.g., the zoom lens system of Example 1. An object image formed through the phototaking optical system 41 is formed on the image pickup surface of a CCD 45 through an optical low-pass filter with an infrared cutting coat applied thereon. The object image received on the CCD 49 is displayed as an electronic image on the liquid crystal monitor 47 attached to the backside of the camera via processing means 51. If this processing means 51 is connected to recording means 52, then it is also possible to record the phototaken electronic image. It is here noted that the recording means 52 may be provided separately from the processing means 51 or, alternatively, may be constructed in such a way that images are written on floppy disks, memory cards, MOs or the like. If a silver-salt film is used instead of the CCD 49, it is then possible to construct a silver-salt camera.


[0735] Further, a finder objective optical system 53 is provided on the finder optical path 44. An object image formed by this finder objective optical system 53 is formed on a viewing frame 57 of an image erection Porro prism 55. In the rear of this Porro prism 55, there is disposed an eyepiece optical system 59 for guiding the erected image to the eyeball E of the observer. It is here noted that cover members 50 are provided on the incident sides of the phototaking optical system 45 and finder objective optical system 53, with a cover member 50 located on the exit side of the eyepiece optical system 59.


[0736] The thus constructed digital camera 40 can be achieved with high performance yet at low cost, because the phototaking optical system 41 is constructed of the inventive zoom lens which has a wide field angle and a high zoom ratio with improved aberrations and is fast with a back focus enough for receiving filters, etc.


[0737] In the FIG. 55 embodiment, plane-parallel plates are used as the cover members 50. However, it is acceptable to use powered lenses instead.


[0738] It is noted that the FIG. 55 embodiment is an example of the digital camera wherein the phototaking optical path 42 is located parallel with the finder optical path 44. If a prism for splitting the finder optical path is provided in association with an image pickup surface of the zoom lens system for the phototaking optical system 41, it is then possible to dispense with the finder objective optical system 53 and Porro prism 55 and, instead, provide a penta prism so as to guide a subject image to the eyeball E of an observer via the phototaking optical system 41.


[0739]
FIG. 56(a) is a conceptual schematic illustrative of an objective optical system for a single-lens reflex camera, in which the inventive zoom lens is incorporated. In this case, too, the zoom lens system of Example 1 is used as an objective optical system 71. An image-formation light beam passing through this objective optical system 71 is split into a phototaking optical path and a finder optical path through a half-silvered mirror prism (a beam splitter or the like) 72. It is here preferable to use a quick-return mirror in place of the half-silvered mirror prism 72, because light quantity losses are avoidable. In the phototaking optical path, there are disposed a filter F such as a low-pass filter or an infrared cut filter and a CCD 73 to form an object image on an image pickup surface of the CCD 73 thorugh the filter F. The finder optical path is provided with a screen mat 74 on a primary image plane formed at a position conjugate to its image pickup surface. This primary image is reflected by a plane mirror 75, and then relayed as a secondary image via a relay optical system 76 where it is erected into an erected image. Finally, the secondary image is guided to the eyeball E of an observer via an eyepiece lens 77.


[0740] In the finder optical path portion shown in FIG. 56(a), the plane mirror 75 and relay optical system 76 may be replaced by a concave mirror prism 78 having positive power, as shown in FIG. 56(b). With this arrangement, it is possible to achieve some reduction in the number of parts and compactness. It is here noted that this concave mirror prism 78 may be composed of an entrance surface having power and an exit surface having power as well as a reflecting surface defined by not only a rotationally symmetric surface (such as a spherical or aspheric surface) but also a non-rotationally symmetric surface such as an anamorphic or free surface. By using a silver-salt film in place of the CCD 73, it is possible to obtain a silver-salt camera with the silver-salt film loaded therein.


[0741] FIGS. 57 to 59 are illustrative of a personal computer that is one exemplary information processor in which the inventive zoom lens is incorporated as an objective optical system. FIG. 57 is a front perspective view of an uncovered personal computer 300, FIG. 58 is a sectional view of a phototaking optical system 303 in the personal computer 300, and FIG. 59 is a side view of the FIG. 57 state. As can be seen from FIGS. 57 to 59, the personal computer 300 comprises a keyboard 301 via which an operator enters information therein from outside, information processing and recording means (not shown), a monitor 302 for displaying information to the operator and a phototakig optical system 303 for phototaking the image of the operator and the images of objects therearound. The monitor 302 used may be any one of a transmission type liquid crystal display device designed to be illuminated from its backside by a backlight (not shown), a reflection type liquid crystal display device wherein images are displayed by reflecting incoming light, a CRT display, and so on. As shown, the phototaking optical system 302 is built in the right upper portion of the monitor 302. However, it is noted that this phototaking optical system 302 may be located everywhere around the monitor 302 or the keyboard 301.


[0742] This phototaking optical system 303 comprises on a phototaking optical path 304 an objective lens 112 formed of the inventive zoom lens (roughly illustrated) and an image pickup device chip 162 for receiving an image. These are built in the personal computer 300.


[0743] An optical low-pass filter is additionally applied onto the image pickup device chip 162 to form a monolithic image pickup unit 160, which can be fitted in the rear end of a barrel 113 of the objective lens 112 in one-touch simple operation. Thus, any center or surface alignment of the objective lens 112 and image pickup device chip 162 can be dispensed with, so that these can be easily assembled together. It is noted that the barrel 113 is provided at the end with a cover glass 114 for protection of the objective lens 112 and the driving mechanism for the zoom lens in the barrel 113 is not shown.


[0744] An object image received on the image pickup device chip 162 is entered in the processing means of the personal computer 300 through a terminal 166, so that it is displayed as an electronic image on the monitor 302. As an example, an image 305 phototaken of the operator is depicted. It is also possible to display this image 305 on a remote display located on the other end of the computer via the processing means and via the Internet or a telephone.


[0745] FIGS. 60(a), 60(b) and 60(c) are illustrative of a telephone, especially a convenient-to-carry portable telephone that is one exemplary information processor in which the inventive zoom lens is incorporated as a phototaking optical system. FIG. 60(a) is a front view of a portable telephone 400, FIG. 60(b) is a side view thereof, and FIG. 60(c) is a sectional view of a phototaking optical system 405. As shown in FIGS. 60(a) to 60(c), the portable telephone 400 comprises a microphone portion 401 for entering operator's voice therein as information, a speaker portion 402 for producing the voice of an operator at the other end, an input dial 403 for allowing an operator to enter information therein, a monitor 404 for displaying the image of the operator or the image of the operator at the other end and information such as telephone numbers and processing means (not shown) for processing image information, communication information, input signals and so on. The monitor 404 used herein is a liquid crystal display device. It is noted that the positions where these parts are mounted are not limited to those illustrated. This phototaking optical system 405 comprises an objective lens 112 formed of the inventive zoom lens (roughly shown) disposed on a phototaking optical path 407 and an image pickup device chip 162 for receiving an object image. These are all built in the portable telephone 400.


[0746] An optical low-pass filter is additionally applied onto the image pickup device chip 162 to form a monolithic image pickup unit 160, which can be fitted in the rear end of a barrel 113 of the objective lens 112 in one-touch simple operation. Thus, any center or surface alignment of the objective lens 112 and image pickup device chip 162 can be dispensed with, so that these can be easily assembled together. It is noted that the barrel 113 is provided at the end with a cover glass 114 for protection of the objective lens 112 and the driving mechanism for the zoom lens in the barrel 113 is not shown.


[0747] An object image received on the image pickup device chip 162 is entered in the processing means (not shown) through a terminal 166, so that it is displayed as an electronic image on the monitor 402 and/or a monitor at the other end. As an example, an image 305 phototaken of the operator is depicted. To transmit images to the operator at the other end, the processing means includes a signal processing function of converting information on the object image received on the image pickup device chip 162 to transmittable signals.


[0748] As can be appreciated from the foregoing, the present invention can provide a wide-angle, high-zoom-ratio zoom lens system which is used for cameras having a small effective image pickup surface size such as a digital camera and compatible with TTL optical finders having a diagonal field angle of at least 70° at wide-angle ends and about 7 to 10 magnifications, and is fast as well, as expressed by an F-number of about 2.0 to 2.8 at the wide-angle end.


Claims
  • 1. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system and has negative refracting power, and a rear lens group having at least two movable subgroups, wherein a focal length f1 of said first lens group and anomalous dispersion ΔθgF of at least one positive lens element in said first lens group satisfy the following conditions:
  • 2. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system, has negative refracting power and comprises at least three negative lens elements while a positive lens element is located nearest to said image side, or three negative lens elements located nearest to said object side while a positive lens element is located on said image side or a negative lens element while two positive lens elements are located nearest to said image side, with any one of surfaces in said second lens group being defined by an aspheric surface, and a rear lens group having at least two movable subgroups and comprising a total of 6 to 11 lens elements inclusive, wherein the following condition is satisfied with respect to an amount of movement Δz1 of said first lens group from said wide-angle end to said telephoto end when said zoom lens system is focused on an object point at infinity and an amount of movement Δz2 of said second lens group from said wide-angle end to said telephoto end when said zoom lens system is focused on an object point at infinity:
  • 3. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system, has negative refracting power and comprises at least three negative lens elements while a positive lens element is located nearest to said image side, or three negative lens elements located nearest to said object side while a positive lens element is located on said image side or a negative lens element while two positive lens elements are located nearest to said image side, with any one of surfaces in said second lens group being defined by an aspheric surface, and a rear lens group having at least two movable subgroups and comprising a total of 6 to 11 lens elements inclusive, wherein the following condition is satisfied with respect to an amount of movement Δz1 of said first lens group from said wide-angle end to said telephoto end when said zoom lens system is focused on an object point at infinity and an amount of movement Δz2 of said second lens group from said wide-angle end to said telephoto end when said zoom lens system is focused on an object point at infinity:
  • 4. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system and has negative refracting power, and a rear lens group having at least two movable subgroups, wherein said first lens group moves toward said image side in a convex reciprocation locus and an amount of movement Δz1WM of said first lens group from a wide angle end to an intermediate focal length of said zoom lens system, given by fM(={square root}{square root over ( )}(fW·fT)), is positive where fW is a composite focal length of said zoom lens system when focused at said wide-angle end on an object point at infinity and fT is a composite focal length of said zoom lens system when focused at said telephoto end on an object point at infinity, with the proviso that the movement of said first lens group lens toward said image side is assumed to be positive.
  • 5. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system and has negative refracting power, and a rear lens group having at least two movable subgroups, wherein the following condition is satisfied with respect to an amount of movement Δz1 of said first lens group from said wide-angle end to said telephoto end when said zoom lens system is focused on an object point at infinity and an amount of movement Δz2 of said second lens group from said wide-angle end to said telephoto end when said zoom lens system is focused on an object point at infinity:
  • 6. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system and has negative refracting power, and a rear lens group having at least two movable subgroups, wherein the following conditions are satisfied with respect to an amount of movement Δz1 of said first lens group from said wide-angle end to said telephoto end when said zoom lens system is focused on an object point at infinity and an amount of movement Δz2 of said second lens group from said wide-angle end to said telephoto end when said zoom lens system is focused on an object point at infinity:
  • 7. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system, has negative refracting power and comprises at least three negative lens elements while a positive lens element is located nearest to said image side, or three negative lens elements located nearest to said object side while a positive lens element is located on said image side or a negative lens element while two positive lens elements are located nearest to said image side, with any one of surfaces in said second lens group being defined by an aspheric surface, and a rear lens group having at least two movable subgroups and comprising a total of 6 to 11 lens elements inclusive, wherein the following conditions are satisfied with respect to a ratio Δβ2 (=β2T/β2W) where β2W and β2T are magnifications of said second lens group at said wide-angle end and said telephoto end, respectively, when said zoom lens system is focused on an object point at infinity and a zoom ratio γ from said wide-angle end to said telephoto end of said zoom lens system:
  • 8. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system, has negative refracting power and comprises at least three negative lens elements while a positive lens element is located nearest to said image side, or three negative lens elements located nearest to said object side while a positive lens element is located on said image side or a negative lens element while two positive lens elements are located nearest to said image side, with any one of surfaces in said second lens group being defined by an aspheric surface, and a rear lens group having at least two movable subgroups and comprising a total of 6 to 11 lens elements inclusive, wherein the following condition is satisfied with respect to a composite magnification βrW of said rear lens group when said zoom lens system is focused at said wide-angle end on an object point at infinity:
  • 9. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system, has negative refracting power and comprises at least three negative lens elements while a positive lens element is located nearest to said image side, or three negative lens elements located nearest to said object side while a positive lens element is located on said image side or a negative lens element while two positive lens elements are located nearest to said image side, with any one of surfaces in said second lens group being defined by an aspheric surface, and a rear lens group having at least two movable subgroups and comprising a total of 6 to 11 lens elements inclusive, wherein all said movable subgroups in said rear lens group have each at least one doublet component and the following condition is satisfied with respect to a composite magnification βrW of said rear lens group when said zoom lens system is focused at said wide-angle end on an object point at infinity:
  • 10. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system, has negative refracting power and comprises at least three negative lens elements while a positive lens element is located nearest to said image side, or three negative lens elements located nearest to said object side while a positive lens element is located on said image side or a negative lens element while two positive lens elements are located nearest to said image side, with any one of surfaces in said second lens group being defined by an aspheric surface, and a rear lens group having at least two movable subgroups and comprising a total of 6 to 11 lens elements inclusive, wherein focusing is effected by any one of subgroups located nearer to an image side of said rear lens group than a positive subgroup of subgroups having negative magnification, said positive subgroup located nearest to an object side of said rear lens group, and the following condition is satisfied with respect to a magnification βRRW of said positive subgroup located nearest to the image side of said rear lens group when said zoom lens system is focused at said wide-angle end on an object point at infinity:
  • 11. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system, has negative refracting power and comprises at least three negative lens elements while a positive lens element is located nearest to said image side, or three negative lens elements located nearest to said object side while a positive lens element is located on said image side or a negative lens element while two positive lens elements are located nearest to said image side, with any one of surfaces in said second lens group being defined by an aspheric surface, and a rear lens group having at least two movable subgroups and comprising a total of 6 to 11 lens elements inclusive, wherein the following conditions are satisfied with respect to an amount of movement ΔzRF of a subgroup of said subgroups in said rear lens group, said subgroup having positive refracting power and located nearest to an object side of said rear lens group, from said wide-angle end to said telephoto end when said zoom lens system is focused on an object point at infinity and an amount of movement ΔzRR of a positive subgroup located nearest to an image side of said rear lens group when said zoom lens system is focused on an object point at infinity:
  • 12. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system, has negative refracting power and comprises at least three negative lens elements while a positive lens element is located nearest to said image side, or three negative lens elements located nearest to said object side while a positive lens element is located on said image side or a negative lens element while two positive lens elements are located nearest to said image side, with any one of surfaces in said second lens group being defined by an aspheric surface, and a rear lens group having at least two movable subgroups and comprising a total of 6 to 11 lens elements inclusive, wherein said rear lens group comprises a subgroup having positive refracting power and negative magnification and a positive subgroup located nearest to an image side of said rear lens group which vary in relative positions thereof during zooming, said two positive subgroups have each at least one doublet component, at least one aspheric surface and at least one lens element formed of a vitreous material with ν>80 where ν is an Abbe constant.
  • 13. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system, has negative refracting power and comprises at least three negative lens elements while a positive lens element is located nearest to said image side, or three negative lens elements located nearest to said object side while a positive lens element is located on said image side or a negative lens element while two positive lens elements are located nearest to said image side, with any one of surfaces in said second lens group being defined by an aspheric surface, and a rear lens group having at least two movable subgroups and comprising a total of 6 to 11 lens elements inclusive, wherein a subgroup located nearest to an image side of said rear lens group has negative refracting power.
  • 14. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system, has negative refracting power and comprises at least three negative lens elements while a positive lens element is located nearest to said image side, or three negative lens elements located nearest to said object side while a positive lens element is located on said image side or a negative lens element while two positive lens elements are located nearest to said image side, with any one of surfaces in said second lens group being defined by an aspheric surface, and a rear lens group having at least two movable subgroups and comprising a total of 6 to 11 lens elements inclusive, wherein a subgroup located nearest to an image side of said rear lens group comprises one negative lens component.
  • 15. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system, has negative refracting power and comprises at least three negative lens elements while a positive lens element is located nearest to said image side, or three negative lens elements located nearest to said object side while a positive lens element is located on said image side or a negative lens element while two positive lens elements are located nearest to said image side, with any one of surfaces in said second lens group being defined by an aspheric surface, and a rear lens group having at least two movable subgroups and comprising a total of 6 to 11 lens elements inclusive, wherein a subgroup located nearest to an image side of said rear lens group remains always fixed in the vicinity of an aperture stop and comprises one negative lens component.
  • 16. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system and has negative refracting power, and at least two rear lens groups which are located subsequent to said second lens group and have a spacing variable during zooming, wherein a focal length f1 of said first lens group satisfies the following condition:
  • 17. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system and has negative refracting power, and at least two rear lens groups which are located subsequent to said second lens group and have a spacing variable during zooming, wherein a focal length f1 of said first lens group and anomalous dispersion ΔθgF of at least one positive lens element in said first lens group satisfy the following conditions:
  • 18. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system and has negative refracting power, and at least two rear lens groups which are located subsequent to said second lens group and have a spacing variable during zooming, wherein the following condition is satisfied with respect to an amount of movement Δz1 of said first lens group from said wide-angle end to said telephoto end when said zoom lens system is focused on an object point at infinity and an amount of movement Δz2 of said second lens group from said wide-angle end to said telephoto end when said zoom lens system is focused on an object point at infinity:
  • 19. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system and has negative refracting power, and at least two rear lens groups which are located subsequent to said second lens group and have a spacing variable during zooming, wherein the following condition is satisfied with respect to an amount of movement Δz1 of said first lens group from said wide-angle end to said telephoto end when said zoom lens system is focused on an object point at infinity and an amount of movement Δz2 of said second lens group from said wide-angle end to said telephoto end when said zoom lens system is focused on an object point at infinity:
  • 20. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system and has negative refracting power, and at least two rear lens groups which are located subsequent to said second lens group and have a spacing variable during zooming, wherein said first lens group moves toward said image side in a convex reciprocation locus and an amount of movement Δz1WM of said first lens group from a wide angle end to an intermediate focal length of said zoom lens system, given by fM(={square root}{square root over ( )}(fW·fT)) where fW is a composite focal length of said zoom lens system when focused at said wide-angle end on an object point at infinity and fT is a composite focal length of said zoom lens system when focused at said telephoto end on an object point at infinity, with the proviso that the movement of said first lens group lens toward said image side is assumed to be positive.
  • 21. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system and has negative refracting power, and at least two rear lens groups which are located subsequent to said second lens group and have a spacing variable during zooming, wherein said first lens group moves toward said image side in a convex reciprocation locus and the following condition is satisfied with respect to an amount of movement Δz1 of said first lens group from said wide-angle end to said telephoto end when said zoom lens system is focused on an object point at infinity and an amount of movement Δz2 of said second lens group from said wide-angle end to said telephoto end when said zoom lens system is focused on an object point at infinity:
  • 22. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system and has negative refracting power, and at least two rear lens groups which are located subsequent to said second lens group and have a spacing variable during zooming, wherein said first lens group moves toward said image side in a convex reciprocation locus and the following conditions are satisfied with respect to an amount of movement Δz1 of said first lens group from said wide-angle end to said telephoto end when said zoom lens system is focused on an object point at infinity and an amount of movement Δz2 of said second lens group from said wide-angle end to said telephoto end when said zoom lens system is focused on an object point at infinity:
  • 23. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system, and has negative refracting power and at least two rear lens groups which are located subsequent to said second lens group and have a spacing variable during zooming, wherein said second lens group comprises at least three negative lens elements while a positive lens element is located nearest to said image side, or three negative lens elements located nearest to said object side while a positive lens element is located on said image side or a negative lens element while two positive lens elements are located nearest to said image side, with any one of surfaces in said second lens group being defined by an aspheric surface, and the following conditions are satisfied with respect to a ratio Δβ2 (=β2T/β2W) where β2W and β2T are magnifications of said second lens group at said wide-angle end and said telephoto end, respectively, when said zoom lens system is focused on an object point at infinity and a zoom ratio γ from said wide-angle end to said telephoto end of said zoom lens system:
  • 24. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system, has negative refracting power and at least two rear lens groups which are located subsequent to said second lens group and have a spacing variable during zooming, wherein the following condition is satisfied with respect to a composite magnification βrW of said rear lens groups when said zoom lens system is focused at said wide-angle end on an object point at infinity:
  • 25. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system and has negative refracting power and at least two rear lens groups which are located subsequent to said second lens group and have a spacing variable during zooming, wherein all said movable subgroups in said rear lens group have each at least one doublet component and the following condition is satisfied with respect to a composite magnification βrW of said rear lens group when said zoom lens system is focused at said wide-angle end on an object point at infinity:
  • 26. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system, has negative refracting power and at least two rear lens groups which are located subsequent to said second lens group and have a spacing variable during zooming, wherein focusing is effected by any one of subgroups located nearer to an image side of said rear lens group than a positive subgroup of subgroups having negative magnification, said positive subgroup located nearest to an object side of said rear lens group, and the following condition is satisfied with respect to a magnification βRRW of said positive subgroup located nearest to the image side of said rear lens group when said zoom lens system is focused at said wide-angle end on an object point at infinity:
  • 27. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system, has negative refracting power and comprises at least three negative lens elements while a positive lens element is located nearest to said image side, or three negative lens elements located nearest to said object side while a positive lens element is located on said image side or a negative lens element while two positive lens elements are located nearest to said image side, with any one of surfaces in said second lens group being defined by an aspheric surface, and a rear lens group having at least two movable subgroups and comprising a total of 6 to 11 lens elements inclusive, wherein the following conditions are satisfied with respect to an amount of movement ΔzRF of a subgroup of said subgroups in said rear lens group, said subgroup having positive refracting power and located nearest to an object side of said rear lens group, from said wide-angle end to said telephoto end when said zoom lens system is focused on an object point at infinity and an amount of movement ΔzRR of a positive subgroup located nearest to an image side of said rear lens group when said zoom lens system is focused on an object point at infinity:
  • 28. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system during zooming from a wide-angle end to a telephoto end of said zoom lens system and has negative refracting power and a rear lens group having a plurality of subgroups, wherein said rear lens group comprises a subgroup having positive refracting power and negative magnification and a positive subgroup located nearest to an image side of said rear lens group, said two positive subgroups varying in relative positions thereof during zooming with a negative subgroup located therebetween, and having each at least one doublet component, at least one aspheric surface and at least one lens element formed of a vitreous material with ν>80 (ν is an Abbe constant).
  • 29. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system and has positive refracting power, a second lens group which moves toward an image side of said zoom lens system during zooming from a wide-angle end to a telephoto end of said zoom lens system and has negative refracting power and a rear lens group having a plurality of subgroups, wherein the following conditions are satisfied with respect to an amount of movement ΔzRF of a subgroup in said rear lens group from said wide-angle end to said telephoto end when said zoom lens system is focused on an object point at infinity, said subgroup having positive refracting power and negative magnification and located nearest to an image side of said rear lens group and an amount of movement ΔzRR of a positive subgroup located nearest to an image side of said rear lens group when said zoom lens system is focused on an object point at infinity, said rear lens group has between said two positive subgroups a negative subgroup varying in a position relative thereto during zooming, and the following condition is satisfied with respect to an amount of movement ΔzRN of said negative subgroup from said wide-angle end to said telephoto end when said zoom lens system is focused on an object point at infinity:
  • 30. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and having positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system and having negative refracting power and a rear lens group which is located subsequent to said second lens group and at least three spacings variable during zooming, wherein a subgroup located nearest to an object side of said rear lens group has negative refracting power.
  • 31. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and having positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system and having negative refracting power and a rear lens group which is located subsequent to said second lens group and at least three spacings variable during zooming, wherein a subgroup located nearest to an object side of said rear lens group comprises one negative lens component.
  • 32. A zoom lens system comprising, in order from an object side thereof, a first lens group which is movable along an optical axis of said zoom lens system during zooming and having positive refracting power, a second lens group which moves toward an image side of said zoom lens system along said optical axis during zooming from a wide-angle end to a telephoto end of said zoom lens system and having negative refracting power and a rear lens group which is located subsequent to said second lens group and at least three spacings variable during zooming, wherein a subgroup located nearest to an object side of said rear lens group remains always fixed in the vicinity of an aperture stop and comprises one negative lens component.
  • 33. The zoom lens system according to claim 1, wherein said subgroup located nearest to said object side of said rear lens group has negative magnification.
  • 34. The zoom lens system according to claim 1, which comprises a zoom zone including a field angle 2ω=70° at which phototaking is possible.
  • 35. The zoom lens system according to claim 1, wherein the following condition is satisfied with respect to a back focus FBW (as calculated on an air basis) of said zoom lens system when focused at said wide-angle end on an object point at infinity:
  • 36. The zoom lens system according to claim 1, wherein the following condition is satisfied with respect to a minimum F-number FW of said zoom lens system when focused at said wide-angle end on an object point at infinity:
  • 37. The zoom lens system according to claim 1, wherein the following condition is satisfied with respect to an entrance pupil position ENP of said zoom lens system at said wide-angle end:
  • 38. The zoom lens system according to claim 1, which is used as an image-formation optical system for a phototaking system (a camera, a video movie, etc.) having an image pickup device having a pixel interval a given by
  • 39. An image pickup system comprising an image pickup device located in the vicinity of an image-formation plane of a zoom lens system as recited in any one of claims 1 to 32.
  • 40. The image pickup system according to claim 40, wherein an electronic image pickup device is used as said image pickup device and a low-pass filter is located between said zoom lens system and said electronic image pickup device.
  • 41. The image pickup system according to claim 40, wherein between said zoom lens system and said electronic image pickup device there is located an optical element for splitting an observation optical path.
Priority Claims (1)
Number Date Country Kind
2000-250577 Aug 2000 JP
Continuations (1)
Number Date Country
Parent 09934074 Aug 2001 US
Child 10441107 May 2003 US