Lens Assembly

BACKGROUND OF THE INVENTION
Field of the Invention

The invention relates to a lens assembly.

Description of the Related Art

The current development trend of a lens assembly for mobil phone is toward high resolution. The number of lenses used in the lens assembly for mobil phone is increasing, making the total length of the lens assembly for mobil phone is getting longer, which can no longer meet the requirements of thin and light for mobile phone. Therefore, the lens assembly needs a new structure in order to meet the requirements of high resolution and miniaturization at the same time.

BRIEF SUMMARY OF THE INVENTION

The invention provides a lens assembly to solve the above problems. The lens assembly of the invention is provided with characteristics of a shortened total lens length, an increased resolution, and still has a good optical performance.

The lens assembly in accordance with an exemplary embodiment of the invention includes a first lens, a second lens, a third lens, and a fourth lens. The first lens is with positive refractive power and includes a concave surface facing an object side and a convex surface facing an image side. The second lens is with negative refractive power and includes a concave surface facing the object side. The third lens is with positive refractive power. The fourth lens is with refractive power and includes a concave surface facing the image side. The first lens, the second lens, the third lens, and the fourth lens are arranged in order from the object side to the image side along an optical axis. The lens assembly satisfies: TTL/f>2; wherein TTL is a total length of optical system of the lens assembly and f is an effective focal length of the lens assembly.

The lens assembly in accordance with another exemplary embodiment of the invention includes a first lens, a second lens, a third lens, a fourth lens, and a reflective element. The first lens is with positive refractive power and includes a convex surface facing an image side. The second lens is with negative refractive power and includes a concave surface facing an object side. The third lens is with positive refractive power. The fourth lens is with refractive power and includes a concave surface facing the image side. The reflective element includes a reflective surface. The first lens, the second lens, the third lens, and the fourth lens are arranged in order from the object side to the image side along an optical axis. The reflective element is disposed between the first lens and the fourth lens. The lens assembly satisfies: 2 mm<L<6 mm; wherein L is an interval from an object side surface of a lens closest to the object side to the reflective surface along the optical axis.

In another exemplary embodiment, the lens assembly further includes a reflective element disposed between the first lens and the fourth lens, the reflective element includes a reflective surface.

In yet another exemplary embodiment, the second lens further includes a convex surface or a concave surface facing the image side, the third lens includes a convex surface facing the object side.

In another exemplary embodiment, the third lens further includes a concave surface or another convex surface facing the image side, the fourth lens is with negative refractive power and further includes a convex surface facing the object side.

In yet another exemplary embodiment, the lens assembly further includes a fifth lens disposed between the object side and the first lens, the fifth lens is a meniscus lens with positive refractive power and includes a convex surface facing the object side and a concave surface facing the image side, the third lens further includes a plane surface or another convex surface facing the image side, the fourth lens is with negative refractive power and further includes a plane surface or a convex surface facing the object side.

In another exemplary embodiment, the lens assembly further includes a fifth lens disposed between the fourth lens and the image side or the third lens and the fourth lens, the fifth lens is with positive refractive power and includes a convex surface facing the image side.

In yet another exemplary embodiment, the fifth lens further includes another convex surface facing the object side, the second lens further includes a convex surface or a concave surface facing the image side, the third lens includes a convex surface facing the object side and a concave surface or a convex surface facing the image side, the fourth lens is with positive or negative refractive power and further includes a convex surface facing the object side.

In another exemplary embodiment, the lens assembly further includes a sixth lens disposed between the third lens and the fifth lens, the sixth lens is a meniscus lens with negative refractive power and includes a concave surface facing the object side and a convex surface facing the image side, the fifth lens is a meniscus lens and further includes a concave surface facing the object side, the second lens further includes another concave surface facing the image side, the third lens further includes another convex surface facing the image side, the fourth lens is with positive refractive power and further includes a convex surface facing the object side.

In yet another exemplary embodiment, the lens assembly satisfies at least any one of the following conditions: 5 mm<ALOD<14 mm; 0<TTL/ALOD<2; 1<(TTL+f)/f_obj1<5; 1<f_obj1/L1T<4; 0.2 mm<L1T×L1SD<2.2 mm²; −4 mm²<L1T×R₁₁<0 mm²; wherein ALOD is a total effective optical diameter of an object side surface of each lens of the lens assembly, TTL is a total length of optical system of the lens assembly, f is an effective focal length of the lens assembly, f_obj1is an effective focal length of a lens closest to the object side, L1T is a thickness along the optical axis of the first lens, L1SD is an effective optical semi-diameter of an image side surface of the first lens, and R₁₁is a radius of curvature of an object side surface of the first lens.

In another exemplary embodiment, the lens assembly satisfies at least any one of the following conditions: 0.5<M1T/L1T<4; 1<TTL/L<5; 0<L/f<2.5; −1<f_obj3/f_obj4<2; wherein M1T is an interval from an image side surface of the first lens to the reflective surface along the optical axis, L1T is a thickness along the optical axis of the first lens, TTL is a total length of optical system of the lens assembly, L is an interval from an object side surface of a lens closest to the object side to the reflective surface along the optical axis, f_obj3is an effective focal length of a lens third close to the object side, f_obj4is an effective focal length of a lens fourth close to the object side, and f is an effective focal length of the lens assembly.

In yet another exemplary embodiment, the lens assembly satisfies: −2 mm<8×M1T−(OD₂+OD₃+OD₄+OD₅)<1 mm; wherein M1T is an interval from an image side surface of the first lens to the reflective surface along the optical axis, OD₂is an effective optical diameter of an object side surface of a lens second close to the object side, OD₃is an effective optical diameter of an object side surface of a lens third close to the object side, OD₄is an effective optical diameter of an object side surface of a lens fourth close to the object side, and OD₅is an effective optical diameter of an object side surface of a lens fifth close to the object side.

In another exemplary embodiment, the second lens further includes a convex surface or a concave surface facing the image side, the third lens includes a convex surface facing the object side.

In yet another exemplary embodiment, the first lens further includes another convex surface facing the object side.

In another exemplary embodiment, the lens assembly satisfies at least any one of the following conditions: 5 mm<ALOD<14 mm; 0<TTL/ALOD<2; wherein ALOD is a total effective optical diameter of an object side surface of each lens of the lens assembly and TTL is a total length of optical system of the lens assembly.

In yet another exemplary embodiment, the lens assembly satisfies at least any one of the following conditions: 1<(TTL+f)/f_obj1<5; −1<f_obj3/f_obj4<2; 1<f_obj1/L1T<4; 0.2 mm²<L1T×L1SD<2.2 mm²; −4 mm²<L1T×R₁₁<0 mm²; 0.5<M1T/L1T<4; 1<TTL/L<5; 0<L/f<2.5; wherein TTL is a total length of optical system of the lens assembly, f is an effective focal length of the lens assembly, f_obj1is an effective focal length of a lens closest to the object side, f_obj3is an effective focal length of a lens third close to the object side, f_obj4is an effective focal length of a lens fourth close to the object side, L1T is a thickness along the optical axis of the first lens, L1SD is an effective optical semi-diameter of an image side surface of the first lens, R₁₁is a radius of curvature of an object side surface of the first lens, M1T is an interval from an image side surface of the first lens to the reflective surface along the optical axis, L1T is a thickness along the optical axis of the first lens, L is an interval from an object side surface of a lens closest to the object side to the reflective surface along the optical axis, and f is an effective focal length of the lens assembly.

In another exemplary embodiment, the lens assembly further includes a fifth lens disposed between the object side and the first lens, the fifth lens is a meniscus lens with positive refractive power and includes a convex surface facing the object side and a concave surface facing the image side, the second lens further includes a convex surface facing the image side, the third lens includes a convex surface facing the image side, the fourth lens is with negative refractive power and further includes a convex surface facing the object side.

in yet another exemplary embodiment, the lens assembly satisfies: 8 mm≤TTL1≤9 mm; wherein TTL1 is an interval from the convex surface of the fifth lens to an image plane along the optical axis.

In another exemplary embodiment, the lens assembly satisfies: D=f/2, 2.85 mm≤D≤2.95 mm; wherein D is an effective diameter of an entrance pupil of the lens assembly and f is an effective focal length of the lens assembly.

In yet another exemplary embodiment, the lens assembly satisfies at least any one of the following conditions: 55 degrees≤FOV≤65 degrees; 0/° C.≤TCE<10×10⁻⁶/° C.; 0.5≤L5T/E≤1.47; Nd₅≥1.9; Vd₅<20; wherein FOV is a field of view of the lens assembly, TCE is a coefficient of thermal expansion of the fifth lens at 25 degrees Celsius, L5T is a thickness along the optical axis of the fifth lens, E is a thickness of the outermost periphery of the fifth lens, Nd₅is an index of refraction of the fifth lens, and Vd₅is an Abbe number of the fifth lens.

A detailed description is given in the following embodiments with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention can be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein:

FIG. 1 is a lens layout and optical path diagram of a lens assembly in accordance with a first embodiment of the invention;

FIG. 2A depicts a field curvature diagram of the lens assembly in accordance with the first embodiment of the invention;

FIG. 2B is a distortion diagram of the lens assembly in accordance with the first embodiment of the invention;

FIG. 2C is a modulation transfer function diagram of the lens assembly in accordance with the first embodiment of the invention;

FIG. 3 is a lens layout and optical path diagram of a lens assembly in accordance with a second embodiment of the invention;

FIG. 4A depicts a field curvature diagram of the lens assembly in accordance with the second embodiment of the invention;

FIG. 4B is a distortion diagram of the lens assembly in accordance with the second embodiment of the invention;

FIG. 4C is a modulation transfer function diagram of the lens assembly in accordance with the second embodiment of the invention;

FIG. 5 is a lens layout and optical path diagram of a lens assembly in accordance with a third embodiment of the invention;

FIG. 6A depicts a field curvature diagram of the lens assembly in accordance with the third embodiment of the invention;

FIG. 6B is a distortion diagram of the lens assembly in accordance with the third embodiment of the invention;

FIG. 6C is a modulation transfer function diagram of the lens assembly in accordance with the third embodiment of the invention;

FIG. 7 is a lens layout and optical path diagram of a lens assembly in accordance with a fourth embodiment of the invention;

FIG. 8A depicts a field curvature diagram of the lens assembly in accordance with the fourth embodiment of the invention;

FIG. 8B is a distortion diagram of the lens assembly in accordance with the fourth embodiment of the invention;

FIG. 8C is a modulation transfer function diagram of the lens assembly in accordance with the fourth embodiment of the invention;

FIG. 9 is a lens layout and optical path diagram of a lens assembly in accordance with a fifth embodiment of the invention;

FIG. 10A depicts a field curvature diagram of the lens assembly in accordance with the fifth embodiment of the invention;

FIG. 10B is a distortion diagram of the lens assembly in accordance with the fifth embodiment of the invention;

FIG. 10C is a modulation transfer function diagram of the lens assembly in accordance with the fifth embodiment of the invention;

FIG. 11 is a lens layout and optical path diagram of a lens assembly in accordance with a sixth embodiment of the invention;

FIG. 12A depicts a field curvature diagram of the lens assembly in accordance with the sixth embodiment of the invention;

FIG. 12B is a distortion diagram of the lens assembly in accordance with the sixth embodiment of the invention;

FIG. 12C is a modulation transfer function diagram of the lens assembly in accordance with the sixth embodiment of the invention;

FIG. 13 is a lens layout and optical path diagram of a lens assembly in accordance with a seventh embodiment of the invention;

FIG. 14A depicts a field curvature diagram of the lens assembly in accordance with the seventh embodiment of the invention;

FIG. 14B is a distortion diagram of the lens assembly in accordance with the seventh embodiment of the invention;

FIG. 14C is a modulation transfer function diagram of the lens assembly in accordance with the seventh embodiment of the invention;

FIG. 15 is a lens layout and optical path diagram of a lens assembly in accordance with an eighth embodiment of the invention;

FIG. 16A depicts a field curvature diagram of the lens assembly in accordance with the eighth embodiment of the invention;

FIG. 16B is a distortion diagram of the lens assembly in accordance with the eighth embodiment of the invention;

FIG. 16C is a modulation transfer function diagram of the lens assembly in accordance with the eighth embodiment of the invention;

FIG. 17 is a lens layout and optical path diagram of a lens assembly in accordance with a ninth embodiment of the invention;

FIG. 18A depicts a field curvature diagram of the lens assembly in accordance with the ninth embodiment of the invention;

FIG. 18B is a distortion diagram of the lens assembly in accordance with the ninth embodiment of the invention;

FIG. 18C is a modulation transfer function diagram of the lens assembly in accordance with the ninth embodiment of the invention;

FIG. 19 is a lens layout and optical path diagram of a lens assembly in accordance with a tenth embodiment of the invention;

FIG. 20A depicts a field curvature diagram of the lens assembly in accordance with the tenth embodiment of the invention;

FIG. 20B is a distortion diagram of the lens assembly in accordance with the tenth embodiment of the invention;

FIG. 20C is a modulation transfer function diagram of the lens assembly in accordance with the tenth embodiment of the invention;

FIG. 21 is a lens layout and optical path diagram of a lens assembly in accordance with a eleventh embodiment of the invention;

FIG. 22A depicts a field curvature diagram of the lens assembly in accordance with the eleventh embodiment of the invention;

FIG. 22B is a distortion diagram of the lens assembly in accordance with the eleventh embodiment of the invention;

FIG. 22C is a modulation transfer function diagram of the lens assembly in accordance with the eleventh embodiment of the invention;

FIG. 23 is a lens layout and optical path diagram of a lens assembly in accordance with a twelfth embodiment of the invention;

FIG. 24A depicts a field curvature diagram of the lens assembly in accordance with the twelfth embodiment of the invention;

FIG. 24B is a distortion diagram of the lens assembly in accordance with the twelfth embodiment of the invention;

FIG. 24C is a modulation transfer function diagram of the lens assembly in accordance with the twelfth embodiment of the invention;

FIG. 25 is a lens layout and optical path diagram of a lens assembly in accordance with a thirteenth embodiment of the invention;

FIG. 26A depicts a field curvature diagram of the lens assembly in accordance with the thirteenth embodiment of the invention;

FIG. 26B is a distortion diagram of the lens assembly in accordance with the thirteenth embodiment of the invention; and

FIG. 26C is a modulation transfer function diagram of the lens assembly in accordance with the thirteenth embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The following description is made for the purpose of illustrating the general principles of the invention and should not be taken in a limiting sense. The scope of the invention is best determined by reference to the appended claims.

The present invention provides a lens assembly including a first lens, a second lens, a third lens, and a fourth lens. The first lens is with positive refractive power and includes a concave surface facing an object side and a convex surface facing an image side. The second lens is with negative refractive power and includes a concave surface facing the object side. The third lens is with positive refractive power. The fourth lens is with refractive power and includes a concave surface facing the image side. The first lens, the second lens, the third lens, and the fourth lens are arranged in order from the object side to the image side along an optical axis. The lens assembly satisfies: TTL/f>1.2; wherein TTL is a total length of optical system of the lens assembly and f is an effective focal length of the lens assembly.

The present invention provides another lens assembly including a first lens, a second lens, a third lens, a fourth lens, and a reflective element. The first lens is with positive refractive power and includes a convex surface facing an image side. The second lens is with negative refractive power and includes a concave surface facing an object side. The third lens is with positive refractive power. The fourth lens is with refractive power and includes a concave surface facing the image side. The reflective element includes a reflective surface. The first lens, the second lens, the third lens, and the fourth lens are arranged in order from the object side to the image side along an optical axis. The reflective element is disposed between the first lens and the fourth lens. The lens assembly satisfies: 2 mm<L<6 mm; wherein L is an interval from an object side surface of a lens closest to the object side to the reflective surface along the optical axis.

Referring to Table 1, Table 2, Table 4, Table 5, Table 7, Table 8, Table 10, Table 11, Table 13, Table 14, Table 16, Table 17, Table 19, Table 20, Table 22, Table 23, Table 25, Table 26, Table 28, Table 29, Table 31, Table 32, Table 34, Table 35, Table 37, and Table 38, wherein Table 1, Table 4, Table 7, Table 10, Table 13, Table 16, Table 19, Table 2 Table 25, Table 28, Table 31, Table 34, and Table 37 show optical specification in accordance with a first, second, third, fourth, fifth, sixth, seventh, eighth, ninth, tenth, eleventh, twelfth, and thirteenth embodiments of the invention respectively and Table 2, Table 5, Table 8, Table 11, Table 14, Table 17, Table 20, Table 23, Table 26, Table 29, Table 32, Table 35, and Table 38 show aspheric coefficients of each aspheric lens in Table 1, Table 4, Table 7, Table 10, Table 13, Table 16, Table 19, Table 22, Table 25, Table 28, Table 31, Table 34, and Table 37 respectively.

FIG. 1, FIG. 3, FIG. 5, FIG. 7, FIG. 9, FIG. 11, FIG. 13, FIG. 15, FIG. 17, 19, FIG. 21, FIG. 23, and FIG. 25 are lens layout and optical path diagrams of the lens assemblies in accordance with the first, second, third, fourth, fifth, sixth, seventh, eighth, ninth, tenth, eleventh, twelfth, and thirteenth embodiments of the invention respectively.

The first lenses L11, L21, L31, L41, L51, L61, L71, L81, L91, L101, L111, L121, L131 are with positive refractive power and made of glass or plastic material, wherein the image side surfaces S15, S23, S33, S43, S53, S63, S73, S83, S93, S105, S115, S125, S135 are convex surfaces and both of the object side surfaces S14, S22, S32, S42, S52, S62, S72, S82, S92, S104, S114, S124, S134 and image side surfaces S15, S23, S33, S43, S53, S63, S73, S83, S93, S105, S115, S125, S135 are aspheric surfaces.

The second lenses L12, L22, L32, L42, L52, L62, L72, L82, L92, L102, L112, L122, and L132 are with negative refractive power and made of glass or plastic material, wherein the object side surfaces S16, S24, S34, S44, S54, S67, S77, S87, S97, S106, S116, S126, S136 are concave surfaces and both of the object side surfaces S16, S24, S34, S44, S54, S67, S77, S87, S97, S106, S116, S126, S.I36 and image side surfaces S17, S25, S35, S45, S55, S68, S78, S88, S98, S107, S117, S127, S137 are aspheric surfaces.

The third lenses L13, L23, L33, L43, L53, L63, L73, L83, L93, L103, L113, L123, and L133 are with positive refractive power and made of glass or plastic material, herein the object side surfaces S18, S26, S36, S46, S56, S69, S79, S89, S99, S108, S118, S128, S138 are convex surfaces.

The fourth lenses L14, L24, L34, L44, L54, L64 L74, L84, L94, L104, L114, L124, L134 are made of glass or plastic material, wherein the image side surfaces S114, S212, S312, S412, S514, S612, S712, S814, S916, S1011, S1111, S1211, S1311 are concave surfaces and the image side surfaces S114, S212, S312, S412, S514, S612, S712, S814, S916, S1011, S1111, S1211, S1311 are aspheric surfaces.

In addition, the lens assemblies 1, 2, 3, 4, 5, 6, 7, 8, 9 satisfy at least one of the following conditions:

TTL/f>1.2; (1)

2 mm<L<6 mm; (2)

5<TTL/OD₁<14; (3)

0.5<ID₁/OD₁<1.5; (4)

5 mm<ALOD<14 mm; (5)

0<TTL/ALOD<2; (6)

1<ALOD/f<4; (7)

1<(TTL+f)/f_obj1<5; (8)

|f_obj1|+|f_obj2|<|f_obj4|; (9)

−3 mm<f_obj3<0 mm; (10)

|f_obj4|<|f_obj5|; (11)

FPD_max<4 mm; (12)

−1<f_obj3/f_obj4<2; (13)

1<f_obj1/L1T<4; (14)

0.2 mm²<L1T×L1SD<2.2 mm²; (15)

−4 mm²<L1T×R₁₁<0 mm²; (16)

0.5<M1T/L1T<4; (17)

1<TTL/L<5; (18)

0<L/f<2.5; (19)

−2 mm<8×M1T−(OD₂+OD₃+OD₄+OD₅)<1 mm; (20)

wherein TTL is a total length of optical system of the lens assemblies 1, 2, 3, 4, 5, 6, 7, 8, 9 for the first to ninth embodiments, that is, an interval from the stops ST1, ST2, ST3, ST4, ST5, ST6, ST7, ST8, ST9 to the image planes IMA1, IMA2, IMA3, IMA4, IMA5, IMA6, IMA7, IMA8, IMA9 along the optical axes OA1, OA2, OA3, OA4, OA5, OA6, OA7, OA8, OA9 respectively, f is an effective focal length of the lens assemblies 1, 2, 4, 5, 6, 7, 8, 9 for the first to ninth embodiments, L is an interval from the object side surfaces S12, S22, S32, S42, S52, S62, S72, S82, S92 of the lenses L15, L21, L31, L41, L51, L61, L71, L81, L91 which are closest to the object side to the reflective surfaces S111, S29, S39, S49, S59, 565, S75, S85, S95 along the optical axes OA1, OA2, OA3, OA4, OA5, OA6, OA7, OA8, OA9 respectively for the first to ninth embodiments, OD₁is an effective optical diameter of the object side surfaces S12, S22, S32, 542, S52 of the lenses L15, L21, L31, L41, L51 which are the closest to the object side respectively for the first to fifth embodiments, OD₂is an effective optical diameter of the object side surfaces S87, S97 of the lenses L82, L92 which are the second close to the object side respectively for the eighth to ninth embodiments, OD₃is an effective optical diameter of the object side surfaces S89, S99 of the lenses L83, L93 which are the third close to the object side respectively for the eighth to ninth embodiments, OD₄is an effective optical diameter of the object side surfaces S811, S911 of the lenses L85, L96 which are the fourth close to the object side respectively for the eighth to ninth embodiments, OD₅is an effective optical diameter of the object side surfaces S813, S913 of the lenses L84, L95 which are the fifth close to the object side respectively for the eighth to ninth embodiments, ID₁is an effective optical diameter of the image side surfaces S13, S23, S33, S43, S53 of the lenses L15, L21, L31, L41, L51 which are the closest to the object side respectively for the first to fifth embodiments, ALOD is a total of the effective optical diameter of the object side surfaces of each lenses for the first to ninth embodiments, f_obj1is an effective focal length of the lenses L15, L21, L31, L41, L51, L61, L71, L81, L91 which are the closest to the object side for the first to ninth embodiments, that is, an effective focal length of the lens which is arranged in order from the object side and is ranged the first, f_obj2is an effective focal length of the lenses L11, L22, L32, L42, L52 which are the second close to the object side for the first to fifth embodiments, that is, an effective focal length of the lens which is arranged in order from the object side and is ranged the second, f_obj3is an effective focal length of the lenses L12, L63, L73, L83, L93 which are the third close to the object side for the first and sixth to ninth embodiments, that is, an effective focal length of the lens which is arranged in order from the object side and is ranged the third, f_obj4is an effective focal length of the lenses L13, L24, L34, L44, L54, L64, L74, L85, L96 which are the fourth close to the object side for the first to ninth embodiments, that is, an effective focal length of the lens which is arranged in order from the object side and is ranged the fourth, f_obj5is an effective focal length of the lens L14 which is the fifth close to the object side for the first embodiment, that is, an effective focal length of the lens which is arranged in order from the object side and is ranged the fifth, FPD_maxis a maximum effective optical diameter of the lenses on the object side of the reflective elements P1, P2, P3, P4, P5 for the first to fifth embodiments, L1T is a thickness of the first lenses L61, L71, L81, L91 along the optical axes OA6, OA7, OA8, OA9 for the sixth to ninth embodiments, M1T is an interval from the image side surfaces S63, S73, S83, S93 of the first lenses L61, L71, L81, L91 to the reflective surfaces S65, S75, S85, S95 along the optical axes OA6, OA7, OA8, OA9 respectively for the sixth to ninth embodiments, L1SD is an effective optical semi-diameter of the image side surfaces S63, S73, S83, S93 of the first lenses L61, L71, L81, L91 for the sixth to ninth embodiments, and R₁₁is a radius of curvature of the object side surfaces S62, S72, S82, S92 of the first lenses L61, L71, L81, L91 for the sixth to ninth embodiments. With the lens assemblies 1, 2, 3, 4, 5, 6, 7, 8, 9 satisfying at least one of the above conditions (1)-(20), the total lens length can be effectively shortened, the resolution can be effectively increased, the aberration can be effectively corrected, and the chromatic aberration can be effectively corrected.

In addition, the lens assemblies 10, 11, 13 satisfy at least one of the following conditions:

D=f/2, 2.85 mm≤D≤2.95 mm; (21)

55 degrees≤FOV≤65 degrees; (22)

8 mm≤TTL1≤9 mm; (23)

Nd
₅≥1.9; (24)

0.5≤L5T, E≤1.47; (25)

0/° C.≤TCE<10×10⁻⁶/° C.; (26)

Vd₅<20; (27)

2.2≥Nd₅≥1.9; (28)

17<Vd₅<20; (29)

wherein f is an effective focal length of the lens assemblies 10, 11, 12, 13 for the tenth to the thirteenth embodiments, D is an effective diameter of an entrance pupil of the lens assemblies 10, 11, 12, 13 for the tenth to thirteenth embodiments, FOV is a full field of view of the lens assemblies 10, 11, 12, 13 for the tenth to thirteenth embodiments, TTL1 is an interval from the object side surfaces S11, S21, S31, S41 of the fifth lenses L105, L115, L125, L135 to the image planes IMA10, IMA11, IMA12, IMA13 along the optical axes OA10, OA11, OA12, OA13 respectively for the tenth to thirteenth embodiments, Nd₅is an index of refraction of the fifth lens L105, L115, L125, L135 for the tenth to thirteenth embodiments, L5T is a thickness of the fifth lenses L105, L115, L125, L135 along the optical axes OA10, OA11, OA12, OA13 for the tenth to thirteenth embodiments, E is a thickness of the outermost periphery of the fifth lenses L105, L115, L125, L135 for the tenth to thirteenth embodiments, TCE is a coefficient of thermal expansion of the fifth lenses L105, L115, L125, L135 at 25 degrees Celsius for the tenth to thirteenth embodiments, and Vd₅is an Abbe number of the fifth lenses L105, L115, L125, L135 for the tenth to thirteenth embodiments. With the lens assemblies 10, 11, 12, 13 satisfying at least one of the above conditions (21)-(29), the total lens length can effectively shortened, the resolution can be effectively increased, the environmental temperature change can be effectively resisted, the aberration can be effectively corrected, and the chromatic aberration can be effectively corrected.

A detailed description of a lens assembly in accordance with a first embodiment of the invention is as follows. Referring to FIG. 1, the lens assembly 1 includes a stop ST1, a fifth lens L15, a first lens L11, a second lens L12, a third lens L13, a reflective element P1, a fourth lens L14, and an optical filter OF1, all of which are arranged in order from an object side to an image side along an optical axis OA1. The reflective element P1 includes an incident surface S110, a reflective surface S111, and an exit surface S112, wherein the incident surface S110 and the exit surface S112 are perpendicular to each other. The reflective surface S111 may contains a metal layer, such as a metal thin film layer of aluminum (Al), silver (Ag), etc., and the reflective surface S111 can be made to include metal layer in any suitable ways, such as coating a metal thin film layer. In this way, the color shift phenomenon and the occurrence of halo during imaging can be avoided, so that the color shift can be effectively improved, the point light source can be effectively concentrated, and has a good image quality for the lens assembly 1. In operation, the light from the object side is reflected by the reflective surface S111 to change the propagation direction and imaged on an image plane IMA1. The image plane IMA1 and the exit surface S112 are parallel to each other. In the first embodiment, the reflective element takes a prism as an example but is not limited thereto. For example, the reflective element may be a reflective mirror which only includes a reflective surface.

According to paragraphs [0079]-[0086], wherein: the fifth lens L15 is a meniscus lens with positive refractive power and made of glass or plastic material, wherein the object side surface S12 is a convex surface, the image side surface S13 is a concave surface, and both of the object side surface S12 and image side surface S13 are aspheric surfaces; the first lens L11 is a meniscus lens, wherein the object side surface S14 is a concave surface; the second lens L12 is a meniscus lens, wherein the image side surface S17 is a convex surface; the third lens L13 is a plane-convex lens, wherein the image side surface S19 is a plane surface and the object side surface S18 is an aspheric surface; the fourth lens L14 is a plane-concave lens with negative refractive power, wherein the object side surface S113 is a plane surface; and both of the object side surface S115 and image side surface S116 of the optical filter OF1 are plane surfaces.

With the above design of the lenses, reflective element P1, stop ST1, and at least any one of the conditions (1)-(20) satisfied, the lens assembly 1 can have an effective shortened total lens length, an effective increased resolution, an effective corrected aberration, and is capable of an effective corrected chromatic aberration.

Table 1 shows the optical specification of the lens assembly 1 in FIG. 1.

TABLE 1

Effective Focal Length = 2.69192 mm F-number = 2.6

Total Optical System Length = 6.354404 mm Field of View = 62.33 degrees

Radius of

Effective

Surface
Curvature
Thickness

Focal Length

Number
(mm)
(mm)
Nd
Vd
(mm)
Remark

S11
∞
−0.05

Stop ST1

S12
1.920745
0.2653972
1.855472
36.86999
7.837847
The Fifth

Lens L15

S13
2.514984
0.3620153

S14
−1.49846
0.8913461
1.72512
52.5106
1.196022
The First

Lens L11

S15
−0.68846
0.1073452

S16
−0.48904
0.3073362
1.671339
19.2429
−2.73696
The Second

Lens L12

S17
−0.83279
0.048041

S18
14.60879
0.4065464
1.606501
57.54
24.01075
The Third

Lens L13

S19
∞
0

S110
∞
1.39
1.802
44.3

Reflective

Element P1

Incident Surface

S111
∞
1.39
1.802
44.3

Reflective

Element P1

Reflective

Surface

S112
∞
0.03982983

Reflective

Element P1

Exit Surface

S113
∞
0.3286899
1.670997
20.16101
−84.1182
The Fourth

Lens L14

S114
56.94673
0.3728562

S115
∞
0.145
1.5
60

Optical Filter

OF1

S116
∞
0.3

The aspheric surface sa z of each aspheric lens in table 1 can be calculated by the following formula:

z=ch
²/{1+[1−(k+1)c²h²]^1/2}+Ah⁴+Bh⁶+Ch⁸+Dh¹⁰+Eh¹²+Fh¹⁴+Gh¹⁶

where c is curvature, h is the vertical distance from the lens surface to the optical axis, k is conic constant and A, B, C, D, E, F and G are aspheric coefficients.

In the first embodiment, the conic constant k and the aspheric coefficients A, B, C, D, E, F, G of each aspheric lens are shown in Table 2.

TABLE 2

Surface

A
B
C

Number
k
E
F
G
D

S12
4.976822
0.083554694
0.34409237
−3.238094
3.1215641

68.051673
−342.36581
468.78044

S13
0.294968
0.20307365
−0.06816194
3.3441261
−78.801281

478.13625
−1388.0483
1402.5153

S14
−18.558
−1.0626488
2.9323527
−25.198071
10.426915

692.26689
−4272.6448
6704.9929

S15
−0.62533
0.22080619
0.013686309
−1.8516094
4.819221

−6.1047322
2.9726467
0.25724607

S16
−1.35718
0.37547258
−0.18473306
0.53075068
−3.100164

8.7872601
−9.3355906
3.3930467

S17
−0.86516
0.35868629
−0.03283751
0.25468627
−0.81134706

1.1538557
−0.88183494
0.34412961

S18
152.0305
0.07683288
−0.02409805
−0.01397754
−0.00419835

0.003333245
0.011395619
−0.0069344

S114
110.0914
0.009061355
0.005413381
0.000280848
−0.0003746

−4.9044E−05
−2.5169E−05
1.30282E−05

Table 3 shows the parameters and condition values for conditions (1)-(12) and (18)-(19) in accordance with the first embodiment of the invention. It can be seen from Table 3 that the lens assembly 1 of the first embodiment satisfies the conditions (1)-(12) and (18)-(19).

TABLE 3

L
3.778027
mm
OD₁
1.04
mm
ID₁
0.960858 mm

ALOD
8.28542
mm
f_obj1
7.837847
mm
f_obj2
1.196022 mm

f_obj3
−2.73696
mm
f_obj4
24.01075
mm
f_obj5
−84.1182 mm

TTL/f
2.360547
TTL/OD₁
6.110004
ID₁/OD₁
0.923902

TTL/ALOD
0.766938
ALOD/f
3.077885
(TTL + f)/f_obj1
1.154185

|f_obj1| + |f_obj2|
9.033869
mm
FPD_max
2.143724
mm
TTL/L
1.681937

L/f
1.403469

By the above arrangements of the lenses, reflective element P1, and stop ST1, the lens assembly 1 of the first embodiment can meet the requirements of optical performance as seen in FIGS. 2A-2C.

It can be seen from FIG. 2A that the field curvature of tangential direction and sagittal direction in the lens assembly 1 of the first embodiment ranges from −1.2 mm to 0.04 mm. It can be seen from FIG. 2B that the distortion in the lens assembly 1 of the first embodiment ranges from −2% to 0%. It can be seen from FIG. 2C that the modulation transfer function of tangential direction and sagittal direction in the lens assembly 1 of the first embodiment ranges from 0.36 to 1.0.

It is obvious that the field curvature and the distortion of the lens assembly 1 of the first embodiment can be corrected effectively, and the resolution of the lens assembly 1 of the first embodiment can meet the requirement. Therefore, the lens assembly 1 of the first embodiment is capable of good optical performance.

Referring to FIG. 3, the lens assembly 2 includes a stop ST2, a first lens L21, a second lens L22, a third lens L23, a reflective element P2, a fourth lens L24, and an optical filter OF2, all of which are arranged in order from an object side to an image side along an optical axis OA2. The reflective element P2 includes an incident surface S28, a reflective surface S29, and an exit surface S210, wherein the incident surface S28 and the exit surface S210 are perpendicular to each other. The reflective surface S29 may contains a metal layer, such as a metal thin film layer of aluminum (Al), silver (Ag), etc., and the reflective surface S29 can be made to include metal layer in any suitable ways, such as coating a metal thin film layer. In this way, the color shift phenomenon and the occurrence of halo during imaging can be avoided, so that the color shift can be effectively improved, the point light source can be effectively concentrated, and has a good image quality for the lens assembly 2. In operation, the light from the object side is reflected by the reflective surface S29 to change the propagation direction and imaged on an image plane IMA2. The image plane IMA2 and the exit surface S210 are parallel to each other. In the second embodiment, the reflective element takes a prism as an example but is not limited thereto. For example, the reflective element may be a reflective mirror which only includes a reflective surface.

According to paragraphs [0079]-[0086], wherein: the first lens L21 is a biconvex lens, wherein the object side surface S22 is a convex surface; the second lens L22 is a meniscus lens, wherein the image side surface S25 is a convex surface; the third lens L23 is a plane-convex lens, wherein the image side surface S27 is a plane surface and the object side surface S26 is an aspheric surface; the fourth lens L24 is a plane-concave lens with negative refractive power and made of glass or plastic material, wherein the object side surface S211 is a plane surface; and both of the object side surface S213 and image side surface S214 of the optical filter OF2 are plane surfaces.

With the above design of the lenses, reflective element P2, stop ST2, and at least any one of the conditions (1)-(20) satisfied, the lens assembly 2 can have an effective shortened total lens length, an effective increased resolution, an effective corrected aberration, and is capable of an effective corrected chromatic aberration.

Table 4 shows the optical specification of the lens assembly 2 in FIG. 3.

TABLE 4

Effective Focal Length = 3.17744 mm F-number = 2.8

Total Optical System Length = 6.420778 mm Field of View = 53.29 degrees

Radius of

Effective

Surface
Curvature
Thickness

Focal Length

Number
(mm)
(mm)
Nd
Vd
(mm)
Remark

S21
∞
−0.03

Stop ST2

S22
3.2631
0.977638
1.460871
50.28586
2.219825
The First

Lens L21

S23
−1.27745
0.383133

S24
−0.50863
0.506806
1.766014
19.23837
−2.27626
The Second

Lens L22

S25
−1.0262
0.05

S26
1.806555
0.411432
1.5352
56.11
3.364525
The Third

Lens L23

S27
∞
0

S28
∞
1.45
1.802
44.3

Reflective

Element P2

Incident Surface

S29
∞
1.45
1.802
44.3

Reflective

Element P2

Reflective

Surface

S210
∞
0

Reflective

Element P2

Exit Surface

S211
∞
0.3
1.671
19.24
−68.294
The Fourth

Lens L24

S212
46.2536
0.25

S213
∞
0.21
1.5
60

Optical Filter

OF2

S214
∞
0.431769

The definition of aspheric surface sag z of each aspheric lens in table 4 is the same as that of in Table 1, and is not described here again.

In the second embodiment, the conic constant k and the aspheric coefficients A, B, C, D, E, F, G of each aspheric lens are shown in Table 5.

TABLE 5

Surface

A
B
C

Number
k
E
F
G
D

S22
0.074745
−0.048011492
−0.3028321
1.6353412
−5.9820629

7.4167268
−1.9108243
1.0042208

S23
0.011904
−0.1828205
0.47158168
−1.6667905
3.1545451

−3.1499386
1.0549963
−0.25722916

S24
−0.6883
0.52533852
0.07700536
0.73537126
−1.5005463

2.0444956
−1.5328175
0.61504974

S25
−0.45923
0.072598913
0.06002844
0.10395908
−0.15761884

0.065592419
0.00191003
−0.00640127

S26
−12.3712
0.016757851
−0.0149707
0.00115345
0.000765445

−0.000158888
−0.00019911
1.93E−05

S212
99.85161
0.016564398
−0.0009307
−0.00020828
3.70E−06

1.85E−07
−1.38E−07
2.90E−08

Table 6 shows the parameters and condition values for conditions (1)-(9), (12), and (18)-(19) in accordance with the second embodiment of the invention. It can be seen from Table 6 that the lens assembly 2 of the second embodiment satisfies the conditions (1)-(9), (12), and (18)-(19).

TABLE 6

L
3.779009 mm
OD₁
1.14468 mm
ID₁
1.51875 mm

ALOD
7.823504 mm
f_obj1
2.219825 mm
f_obj2
−2.27626 mm

f_obj4
−68.294 mm

TTL/f
2.020739
TTL/OD₁
5.609234
ID₁/OD₁
1.32679

TTL/ALOD
0.820704
ALOD/f
2.462204
(TTL + f)/f_obj1
4.323862

|f_obj1| + |f_obj2|
4.496082 mm
FPD_max
2.40044 mm
TTL/L
1.699064

L/f
1.189325

By the above arrangements of the lenses, reflective element P2, and stop ST2, the lens assembly 2 of the second embodiment can meet the requirements of optical performance as seen in FIGS. 4A-4C.

It can be seen from FIG. 4A that the field curvature of tangential direction and sagittal direction in the lens assembly 2 of the second embodiment ranges from −0.09 mm to 0.04 mm. It can be seen from FIG. 4B that the distortion in the lens assembly 2 of the second embodiment ranges from 0% to 2%. It can be seen from FIG. 4C that the modulation transfer function of tangential direction and sagittal direction in the lens assembly 2 of the second embodiment ranges from 0.23 to 1.0.

It is obvious that the field curvature and the distortion of the lens assembly 2 of the second embodiment can be corrected effectively, and the resolution of the lens assembly 2 of the second embodiment can meet the requirement. Therefore, the lens assembly 2 of the second embodiment is capable of good optical performance.

Referring to FIG. 5, the lens assembly 3 includes a stop ST3, a first lens L31, a second lens L32, a third lens L33, a reflective element P3, a fourth lens L34, and an optical filter OF3, all of which are arranged in order from an object side to an image side along an optical axis OA3. The reflective element P3 includes an incident surface S38, a reflective surface S39, and an exit surface S310, wherein the incident surface S38 and the exit surface S310 are perpendicular to each other. The reflective surface S39 may contains a metal layer, such as a metal thin film layer of aluminum (Al), silver (Ag), etc., and the reflective surface S39 can be made to include metal layer in any suitable ways, such as coating a metal thin film layer. In this way, the color shift phenomenon and the occurrence of halo during imaging can be avoided, so that the color shift can be effectively improved, the point light source can be effectively concentrated, and has a good image quality for the lens assembly 3. In operation, the light from the object side is reflected by the reflective surface S39 to change the propagation direction and imaged on an image plane IMA3. The image plane IMA3 and the exit surface S310 are parallel to each other. In the third embodiment, the reflective element takes a prism as an example but is not limited thereto. For example, the reflective element may be a reflective mirror which only includes a reflective surface.

According to paragraphs [0079]-[0086], wherein: the first lens L31 is a meniscus lens, wherein the object side surface S32 is a concave surface; the second lens L32 is a meniscus lens, wherein the image side surface S35 is a convex surface; the third lens L33 is a meniscus lens, wherein the image side surface S37 is a concave surface and both of the object side surface S36 and image side surface S37 are aspheric surfaces; the fourth lens L34 is a meniscus lens with negative refractive power and made of glass or plastic material, wherein the object side surface S311 is a convex surface and the object side surface S311 is an aspheric surface; and both of the object side surface S313 and image side surface S314 of the optical filter OF3 are plane surfaces.

With the above design of the lenses, reflective element P3, stop ST3, and at least any one of the conditions (1)-(20) satisfied, the lens assembly 3 can have an effective shortened total lens length, an effective increased resolution, an effective corrected aberration, and is capable of an effective corrected chromatic aberration.

Table 7 shows the optical specification of the lens assembly 3 in FIG. 5.

TABLE 7

Effective Focal Length = 3.07095 mm F-number = 2.48

Total Optical System Length = 6.737603 mm Field of View = 54.88 degrees

Radius of

Effective

Surface
Curvature
Thickness

Focal Length

Number
(mm)
(mm)
Nd
Vd
(mm)
Remark

S31
∞
0.05

Stop ST3

S32
−8.27838
1.032199
1.802637
42.46164
2.557175
The First

Lens L31

S33
−1.74218
0.560109

S34
−0.59054
0.386854
1.671268
19.23837
−2.03744
The Second

Lens L32

S35
−1.30509
0.047319

S36
1.449244
0.498884
1.593194
67.0001
2.594658
The Third

Lens L33

S37
20.71585
0.027937

S38
∞
1.39
1.802
44.3

Reflective

Element P3

Incident Surface

S39
∞
1.39
1.802
44.3

Reflective

Element P3

Reflective

Surface

S310
∞
0.063172

Reflective

Element P3

Exit Surface

S311
3.484569
0.3
1.671
25.9586
−41.9926
The Fourth

Lens L34

S312
3.834537
0.3

S313
∞
0.145
1.5
60

Optical Filter

OF3

S314
∞
0.54613

The definition of aspheric surface sag z of each aspheric lens in table 7 is the same as that of in Table 1, and is not described here again.

In the third embodiment, the conic constant k and the aspheric coefficients A, B, C, D, E, F, G of each aspheric lens are shown in Table 8.

TABLE 8

Surface

A
B
C

Number
k
E
F
G
D

S32
1.85692
−0.03283118
−0.51476486
2.357223
−6.3265202

8.7153023
−7.7991946
5.05023

S33
−2.19313
−0.14408601
0.2533266
−1.1187475
2.4235947

−2.42689
0.62311844
0.26997132

S34
−0.75595
0.68959987
−0.86578972
0.98166611
−0.44154887

0.57687114
−1.8244609
1.3934062

S35
−0.46648
0.12091949
−0.06434362
0.084589559
−0.1210699

0.071602666
−0.00895967
−0.00443879

S36
−10.8268
0.046370156
−0.03910288
0.012386566
−0.0003165

−0.00291462
0.000278475
3.96E−04

S37
20.52489
−0.00570729
0.001837149
−0.00231611
−0.00082079

−0.00048266
−0.00014138
0.000309606

S311
−5.24682
−0.03786211
−0.00555871
−0.0016182
0.000209891

0.000320484
4.64E−05
−2.53E−05

S312
−8.05917
0.000424071
−0.00995192
0.001154838
3.45E−04

6.23E−06
−7.09E−06
−1.25E−06

Table 9 shows the parameters and condition values for conditions (1)-(9), (12), and (18)-(19) in accordance with the third embodiment of the invention. It can be seen from Table 9 that the lens assembly 3 of the third embodiment satisfies the conditions (1)-(9), (12), and (18)-(19).

TABLE 9

L
3.9433
mm
OD₁
1.250318 mm
ID₁
1.4
mm

ALOD
7.711868
mm
f_obj1
2.557175 mm
f_obj2
−2.03744
mm

f_obj4
−41.9926
mm

TTL/f
2.19398
TTL/OD₁
5.388711
ID₁/OD₁
1.119715

TTL/ALOD
0.873667
ALOD/f
2.511232
(TTL + f)/f_obj1
3.835699

|f_obj1| + |f_obj2|
4.594618
mm
FPD_max
2.329588 mm
TTL/L
1.70862

L/f
1.284065

By the above arrangements of the lenses, reflective element P3, and stop ST3, the lens assembly 3 of the third embodiment can meet the requirements of optical performance as seen in FIGS. 6A-6C.

It can be seen from FIG. 6A that the field curvature of tangential direction and sagittal direction in the lens assembly 3 of the third embodiment ranges from −0.12 mm to 0.02 mm. It can be seen from FIG. 6B that the distortion in the lens assembly 3 of the third embodiment ranges from 0% to 2%. It can be seen from FIG. 6C that the modulation transfer function of tangential direction and sagittal direction in the lens assembly 3 of the third embodiment ranges from 0.35 to 1.0.

It is obvious that the field curvature and the distortion of the lens assembly 3 of the third embodiment can be corrected effectively, and the resolution of the lens assembly 3 of the third embodiment can meet the requirement. Therefore, the lens assembly 3 of the third embodiment is capable of good optical performance.

Referring to FIG. 7, the lens assembly4 includes a stop ST4, a first lens L41, a second lens L42, a third lens L43, a reflective element P4, a fourth lens L44, a fifth lens L45, and an optical filter OF4, all of which are arranged in order from an object side to an image side along an optical axis OA4. The reflective element P4 includes an incident surface S48, a reflective surface S49, and an exit surface S410, wherein the incident surface S48 and the exit surface S410 are perpendicular to each other. The reflective surface S49 may contains a metal layer, such as a metal thin film layer of aluminum (Al), silver (Ag), etc., and the reflective surface S49 can be made to include metal layer in any suitable ways, such as coating a metal thin film layer. In this way, the color shift phenomenon and the occurrence of halo during imaging can be avoided, so that the color shift can be effectively improved, the point light source can be effectively concentrated, and has a good image quality for the lens assembly 4. In operation, the light from the object side is reflected by the reflective surface S49 to change the propagation direction and imaged on an image plane IMA4. The image plane IMA4 and the exit surface S410 are parallel to each other. In the fourth embodiment, the reflective element takes a prism as an example but is not limited thereto. For example, the reflective element may be a reflective mirror which only includes a reflective surface.

According to paragraphs [0079]-[0086], wherein: the first lens L41 is a meniscus lens, wherein the object side surface S42 is a concave surface; the second lens L42 is a meniscus lens, wherein the image side surface S45 is a convex surface; the third lens L43 is a meniscus lens, wherein the image side surface S47 is a concave surface and both of the object side surface S46 and image side surface S47 are aspheric surfaces; the fourth lens L44 is a meniscus lens with negative refractive power and made of glass or plastic material, wherein the object side surface S411 is a convex surface and the object side surface S411 is an aspheric surface; the fifth lens L45 is a biconvex lens with positive refractive and made of glass or plastic material, wherein the object side surface S413 is a convex surface, the image side surface S414 is a convex surface, and both of the object side surface S413 and image side surface S414 are aspheric surfaces; and both of the object side surface S415 and image side surface S416 of the optical filter OF4 are plane surfaces.

With the above design of the lenses, reflective element P4, stop ST4, and at least any one of the conditions (1)-(20) satisfied, the lens assembly 4 can have an effective shortened total lens length, an effective increased resolution, an effective corrected aberration, and is capable of an effective corrected chromatic aberration.

Table 10 shows the optical specification of the lens assembly 4 in FIG. 7.

TABLE 10

Effective Focal Length = 3.06825 mm F-number = 2.48

Total Optical System Length = 7.097378 mm Field of View = 55.00 degrees

Radius of

Effective

Surface
Curvature
Thickness

Focal Length

Number
(mm)
(mm)
Nd
Vd
(mm)
Remark

S41
∞
0.07

Stop ST4

S42
−5.54134
0.989287
1.801505
39.99998
2.861517
The First

Lens L41

S43
−1.75691
0.542297

S44
−0.59747
0.354514
1.671268
19.23837
−2.17272
The Second

Lens L42

S45
−1.2466
0.047319

S46
1.463613
0.498884
1.592617
67.00001
2.631132
The Third

Lens L43

S47
19.9944
0.081931

S48
∞
1.42
1.802
44.3

Reflective

Element P4

Incident Surface

S49
∞
1.42
1.802
44.3

Reflective

Element P4

Reflective

Surface

S410
∞
0.130012

Reflective

Element P4

Exit Surface

S411
3.350262
0.3
1.671
19.23999
−136.303
The Fourth

Lens L44

S412
3.350728
0.239519

S413
124.3329
0.232795
1.5352
56.11
11.16685
The Fifth

Lens L45

S414
−6.29564
0.1

S415
∞
0.145
1.5
60

Optical Filter

OF4

S416
∞
0.525821

The definition of aspheric surface sag z of each asp lens in table 10 is the same as that of in Table 1, and is not described here again.

In the fourth embodiment, the conic constant k and the aspheric coefficients A, B, C, D, E, F, G of each aspheric lens are shown in Table 11.

TABLE 11

Surface

A
B
C

Number
k
E
F
G
D

S42
1.219274
−0.03602155
−0.4856594
2.2884042
−6.4411208

9.0615729
−7.1735785
3.2656249

S43
−1.999641
−0.15262273
0.24937921
−1.0908768
2.404109

−2.5037565
0.53624724
0.53232278

S44
−0.7158636
0.65344018
−0.87515526
1.0760046
−0.45984854

0.3591053
−1.9976787
1.9645166

S45
−0.5362424
0.13140721
−0.07993976
0.074686371
−0.11486832

0.076430574
−0.01043467
−0.00370993

S46
−9.851534
0.054265844
−0.03613012
0.011437864
−0.00064248

−0.00257327
0.000552514
0.000189864

S47
100.2754
−0.0024418
0.001481947
−0.00150654
−0.00053277

−0.00073606
−0.00035132
0.00035109

S411
−6.801962
−0.04175006
−0.00681522
−0.00180852
0.000357034

0.000347889
4.17E−05
−3.38E−05

S412
−8.924384
−0.00026158
−0.0102123
0.001078722
0.000247299

−1.73E−05
−1.02E−05
−5.86E−08

S413
4322.146
0.008810033
−0.00177261
−0.00050394
−5.76E−05

1.88E−06
1.60E−06
2.04E−07

S414
−3.81E+15
−0.00550205
0.000286846
0.000182882
3.11E−05

2.84E−06
−6.89E−07
−1.28E−07

Table 12 shows the parameters and condition values for conditions (1)-(9), (12), and (18)-(19) in accordance with the fourth embodiment of the invention. It can be seen from Table 12 that the lens assembly 4 of the fourth embodiment satisfies the conditions (1)-(9), (12), and (18)-(19).

TABLE 12

L
3.934231 mm
OD₁
1.237022 mm
ID₁
1.4
mm

ALOD
10.64337 mm
f_obj1
2.861517 mm
f_obj2
−2.17272
mm

f_obj4
−136.303 mm

TTL/f
2.313168
TTL/OD₁
5.737471
ID₁/OD₁
1.13175

TTL/ALOD
0.666836
ALOD/f
3.468872
(TTL + f)/f_obj1
3.552531

|f_obj1| + |f_obj2|
5.034233 mm
FPD_max
2.377948 mm
TTL/L
1.804006

L/f
1.282239

By the above arrangements of the lenses, reflective element P4, and stop ST4, the lens assembly 4 of the fourth embodiment can meet the requirements of optical performance as seen in FIGS. 8A-8C.

It can be seen from FIG. 8A that the field curvature of tangential direction and sagittal direction in the lens assembly 4 of the fourth embodiment ranges from −0.12 mm to 0.02 mm. It can be seen from FIG. 8B that the distortion in the lens assembly 4 of the fourth embodiment ranges from −0.15% to 0.3%. It can be seen from FIG. 8C that the modulation transfer function of tangential direction and sagittal direction in the lens assembly 4 of the fourth embodiment ranges from 0.41 to 1.0.

It is obvious that the field curvature and the distortion of the lens assembly 4 of the fourth embodiment can be corrected effectively, and the resolution of the lens assembly 4 of the fourth embodiment can meet the requirement. Therefore, the lens assembly 4 of the fourth embodiment is capable of good optical performance.

Referring to FIG. 9, the lens assembly 5 includes a stop ST5, a first lens L51, a second lens L52, a third lens L53, a reflective element P5, a fifth lens L55, a fourth lens L54, and an optical filter OF5, all of which are arranged in order from an object side to an image side along an optical axis OA5. The reflective element P5 includes an incident surface S58, a reflective surface S59, and an exit surface S510, wherein the incident surface S58 and the exit surface S510 are perpendicular to each other. The reflective surface S59 may contains a metal layer, such as a metal thin film layer of aluminum (Al), silver (Ag), etc., and the reflective surface S59 can be made to include metal layer in any suitable ways, such as coating a metal thin film layer. In this way, the color shift phenomenon and the occurrence of halo during imaging can be avoided, so that the color shift can be effectively improved, the point light source can be effectively concentrated, and has a good image quality for the lens assembly 5. In operation, the light from the object side is reflected by the reflective surface S59 to change the propagation direction and imaged on an image plane IMA5. The image plane IMA5 and the exit surface S510 are parallel to each other. In the fifth embodiment, the reflective element takes a prism as an example but is not limited thereto. For example, the reflective element may be a reflective mirror which only includes a reflective surface.

According to paragraphs [0079]-[0086], wherein: the first lens L51 is a meniscus lens, wherein the object side surface S52 is a concave surface; the second lens L52 is a meniscus lens, wherein the image side surface S55 is a convex surface; the third lens L53 is a meniscus lens, wherein the image side surface S57 is a concave surface and both of the object side surface S56 and image side surface S57 are aspheric surfaces; the fifth lens L55 is a biconvex lens with positive refractive power and made of glass or plastic material, wherein the object side surface S511 is a convex surface, the image side surface S512 is a convex surface, and both of the object side surface S511 and image side surface S512 are aspheric surfaces; the fourth lens L54 is a meniscus lens with negative refractive power and made of glass or plastic material, wherein the object side surface S513 is a convex surface and the object side surface S513 is an aspheric surface; and both of the object side surface S515 and image side surface S516 of the optical filter OF5 are plane surfaces.

With the above design of the lenses, reflective element P5, stop ST5, and at least any one of the conditions (1)-(20) satisfied, the lens assembly 5 can have an effective shortened total lens length, an effective increased resolution, an effective corrected aberration, and is capable of an effective corrected chromatic aberration.

Table 13 shows the optical specification of the lens assembly 5 in FIG. 9.

TABLE 13

Effective Focal Length = 3.06826 mm F-number = 2.6

Total Optical System Length = 7.341773 mm Field of View = 54.96 degrees

Radius of

Effective

Surface
Curvature
Thickness

Focal Length

Number
(mm)
(mm)
Nd
Vd
(mm)
Remark

S51
∞
0.07

Stop ST5

S52
−4.39042
0.983474
1.801502
39.99999
3.061721
The First

Lens L51

S53
−1.73644
0.563924

S54
−0.60926
0.312458
1.671268
19.23837
−2.17488
The Second

Lens L52

S55
−1.2539
0.047319

S56
1.490571
0.498884
1.59183
67.00004
2.268636
The Third

Lens L53

S57
20.06779
0.139272

S58
∞
1.4231
1.802
44.3

Reflective

Element P5

Incident Surface

S59
∞
1.4231
1.802
44.3

Reflective

Element P5

Reflective

Surface

S510
∞
0.074659

Reflective

Element P5

Exit Surface

S511
7.081442
0.428229
1.5352
56.11
6.312641
The Fifth

Lens L55

S512
−6.36407
0.111748

S513
2.396352
0.3
1.671
19.23996
−11.8433
The Fourth

Lens L54

S514
1.751843
0.4

S515
∞
0.145
1.5
60

Optical Filter

OF5

S516
∞
0.420607

The definition of aspheric surface sag z of each aspheric lens in table 13 is the same as that of in Table 1, and is not described here again.

In the fifth embodiment, the conic constant k and the aspheric coefficients A, B, C, D, E, F, G of each aspheric lens are shown in Table 14.

TABLE 14

Surface

A
B
C

Number
k
E
F
G
D

S52
0.352.453
−0.03422112
−0.45802357
2.2693686
−6.4909192

9.046813
−6.9516731
3.2895086

S53
−2.40009
−0.14450985
0.21758413
−1.0525346
2.4379204

−2.5465537
0.35927899
0.77433394

S54
−0.71996
0.64455126
−0.91019912
1.0470208
−0.41689718

0.45189718
−1.8985688
1.7996989

S55
−0.55955
0.13370732
−0.07924532
0.071852647
−0.11445011

0.086059915
−0.00541713
−0.00829265

S56
−11.8096
0.053502886
−0.03530097
0.012714455
0.00016147

−0.00237709
0.000397931
0.000120715

S57
−99.9462
−0.00815003
0.002534206
0.000202537
1.66E−05

−0.00065772
−0.00045445
0.000285441

S511
−12.3666
−0.00360962
−0.0020524
7.16E−06
0.000127816

4.28E−05
4.33E−06
−2.58E−06

S512
−16.6528
−0.00027334
0.000661254
0.000162137
6.74E−05

2.97E−05
1.43E−05
3.51E−06

S513
−10.8915
−0.04134912
−0.00522074
−0.00145687
0.000258147

0.000332458
4.75E−05
−2.70E−05

S514
−6.6787
−0.00560482
−0.01002556
0.001256401
0.000350737

4.80E−06
−7.74E−06
−1.34E−06

Table 15 shows the parameters and condition values for conditions (1)-(9), (12), and (18)-(19) in accordance with the fifth embodiment of the invention. It can be seen from Table 15 that the lens assembly 5 of the fifth embodiment satisfies the conditions (1)-(9), (12), and (18)-(19).

TABLE 15

L
3.96843 mm
OD₁
1.248812 mm
ID₁
1.44
mm

ALOD
11.30868 mm
f_obj1
3.061721 mm
f_obj2
−2.17488
mm

f_obj4
6.312641 mm

TTL/f
2.392813
TTL/OD₁
5.879006
ID₁/OD₁
1.153096

TTL/ALOD
0.649216
ALOD/f
3.685698
(TTL + f)/f_obj1
3.400059

|f_obj1| + |f_obj2|
5.236605 mm
FPD_max
2.469688 mm
TTL/L
1.850045

L/f
1.293381

By the above arrangements of the lenses, reflective element P5, and stop ST5, the lens assembly 5 of the fifth embodiment can meet the requirements of optical performance as seen in FIGS. 10A-10C.

It can be seen from FIG. 10A that the field curvature of tangential direction and sagittal direction in the lens assembly 5 of the fifth embodiment ranges from −0.10 mm to 0.025 mm. It can be seen from FIG. 10B that the distortion in the lens assembly 5 of the fifth embodiment ranges from 0% to 2%. It can be seen from FIG. 10C that the modulation transfer function of tangential direction and sagittal direction in the lens assembly 5 of the fifth embodiment ranges from 0.40 to 1.0.

It is obvious that the field curvature and the distortion of the lens assembly 5 of the fifth embodiment can be corrected effectively, and the resolution of the lens assembly 5 of the fifth embodiment can meet the requirement. Therefore, the lens assembly 5 of the fifth embodiment is capable of good optical performance.

Referring to FIG. 11, the lens assembly 6 includes a stop ST6, a first lens L61, a reflective element P6, a second lens L62, a third lens L63, a fourth lens L64, and an optical filter OF6, all of which are arranged in order from an object side to an image side along an optical axis OA6. The reflective element P6 includes an incident surface S64, a reflective surface S65, and an exit surface S66, wherein the incident surface S64 and the exit surface S66 are perpendicular to each other. The reflective surface S65 may contains a metal layer, such as a metal thin film layer of aluminum (Al), silver (Ag), etc., and the reflective surface S65 can be made to include metal layer in any suitable ways, such as coating a metal thin film layer. In this way, the color shift phenomenon and the occurrence of halo during imaging can be avoided, so that the color shift can be effectively improved, the point light source can be effectively concentrated, and has a good image quality for the lens assembly 6. In operation, the light from the object side is reflected by the reflective surface S65 to change the propagation direction and imaged on an image plane IMA6. The image plane IMA6 and the exit surface S66 are parallel to each other. In the sixth embodiment, the reflective element takes a prism as an example but is not limited thereto. For example, the reflective element may he a reflective mirror which only includes a reflective surface.

According to paragraphs [0079]-[0086], wherein: the first lens L61 is a meniscus lens, wherein the object side surface S62 is a concave surface; the second lens L62 is a biconcave lens, wherein the image side surface S68 is a concave surface; the third lens L63 is a biconvex lens, wherein the image side surface 8610 is a convex surface and both of the object side surface S609 and image side surface S610 are aspheric surfaces; the fourth lens L64 is a meniscus lens with negative refractive power and made of glass or plastic material, wherein the object side surface S611 is a convex surface and the object side surface S611 is an aspheric surface; and both of the object side surface S613 and image side surface S614 of the optical filter OF6 are plane surfaces.

With the above design of the lenses, reflective element P6, stop ST6, and at least any one of the conditions (1)-(20) satisfied, the lens assembly 6 can have an effective shortened total lens length, an effective increased resolution, an effective corrected aberration, and is capable of an effective corrected chromatic aberration.

Table 16 shows the optical specification of the lens assembly 6 in FIG. 11.

TABLE 16

Effective Focal Length = 2.4918 mm F-number = 2.48

Total Optical System Length = 7.254615 mm Field of View = 38.78 degrees

Radius of

Effective

Surface
Curvature
Thickness

Focal Length

Number
(mm)
(mm)
Nd
Vd
(mm)
Remark

S61
∞
0.08432

Stop ST6

S62
−2.54656
1.430805
1.85605
40.28218
2.574553
The First

Lens L61

S63
−1.49194
0.011211

S64
∞
1.303
2.0033
28.32

Reflective

Element P6

Incident Surface

S65
∞
1.303
2.0033
28.32

Reflective

Element P6

Reflective

Surface

S66
∞
0.09988

Reflective

Element P6

Exit Surface

S67
−2.50592
0.281861
1.651
19.24
−2.513553
The Second

Lens L62

S68
5.060772
0.023067

S69
4.41957
1.42177
1.5352
56.11
1.960286
The Third

Lens L63

S610
−1.22633
0.012178

S611
1.320806
0.291233
1.671
19.23991
−8.025317
The Fourth

Lens L64

S612
0.967984
0.35

S613
∞
0.145
1.5
60

Optical Filter

OF6

S614
∞
0.49729

The aspheric surface sag z of each aspheric lens in table 16 can be calculated by the following formula:

z=ch
²/{1+[1−(k+1)c²h²]^1/2}+Ah⁴+Bh⁶+Ch⁸+Dh¹⁰+Eh¹²+Fh¹⁴+Gh¹⁶+Hh¹⁸+Ih²⁰

where c is curvature, h is the vertical distance from the lens surface to the optical axis, k is conic constant and A, B, C, D, G, H and I are aspheric coefficients.

In the sixth embodiment, the conic constant k and the aspheric coefficients A, B, C, D, E, G, H, I of each aspheric lens are shown in Table 17.

TABLE 17

Surface

A
B
C
D

Number
k
F
G
H
I
E

S62
13.75142
0.059633072
0.197975902
−1.353695553
6.011150013
32.00738145

−197.1765565
−516.6148698
4973.695118
−8072.082431

S63
0.844515
0.075082368
0.025370142
−0.078201244
0.373403036
−0.286249347

−0.896557483
2.03681989
−1.42041644
0.297002462

S67
0.315678
−0.19884293
0.03114807
0.03883311
−0.0023693
−0.01358974

−0.0041441
0.003413
0.002526
−0.0011816

S68
11.50862
−0.04801084
−0.01774108
0.01732643
0.009153
−0.0014184

−0.001882
−0.00062629
0.0002499
0.0001749

S69
−7.72515
−0.05136858
0.02018952
−0.01897868
−0.006259
0.006072

0.005693
−0.0016121
−0.0024039
0.0008936

S610
−3.31646
−0.02385783
0.02126333
−0.00022589
−0.0031994
−0.00056687

−0.000065107
−0.00032328
−0.00011925
0.0001142

S611
−1.10491
0.19171951
0.02421953
−0.01275306
−0.0037512
−0.00054874

0.0002613
0.0001886
0.00002875
−0.000021294

S612
−2.37611
0.20702235
−0.03961328
−0.0069432
0.001398
0.0005286

−0.00002298
−0.000038561
−4.8794E−06
0.000003042

Table 18 shows the parameters and condition values for conditions (1)-(2), (5)-(6), (8), and (13)-(19) in accordance with the sixth embodiment of the invention. It can be seen from Table 18 that the lens assembly 6 of the sixth embodiment satisfies the conditions (1)-(2), (5)-(6), (8), and (13)-(19).

TABLE 18

L
2.745337
mm
ALOD
9.774
mm
f_obj1
2.574553
mm

f_obj3
1.960286
mm
f_obj4
−8.025317
mm
L1T
1.430805
mm

L1SD
0.877
mm
R₁₁
−2.54656
mm
M1T
1.31421124
mm

TTL/f
3.294779
TTL/ALOD
0.83937
(TTL + f)/f_obj1
4.154623

f_obj3/f_obj4
−0.2443
L1T × L1SD
1.25411
mm²
L1T × R₁₁
−3.64158
mm²

f_obj1/L1T
1.8
mm
M1T/L1T
0.91902
TTL/L
2.98834

L/f
1.102545

By the above arrangements of the lenses, reflective element P6, and stop ST6, the lens assembly 6 of the sixth embodiment can meet the requirements of optical performance as seen in FIGS. 12A-12C.

It can be seen from FIG. 12A that the field curvature of tangential direction and sagittal direction in the lens assembly 6 of the sixth embodiment ranges from −0.1 mm to 0.3 mm. It can be seen from FIG. 12B that the distortion in the lens assembly 6 of the sixth embodiment ranges from 0% to 2%. It can be seen from FIG. 12C that the modulation transfer function of tangential direction and sagittal direction in the lens assembly 6 of the sixth embodiment ranges from 0.49 to 1.0.

It is obvious that the field curvature and the distortion of the lens assembly 6 of the sixth embodiment can be corrected effectively, and the resolution of the lens assembly 6 of the sixth embodiment can meet the requirement. Therefore, the lens assembly 6 of the sixth embodiment is capable of good optical performance.

Referring to FIG. 13, the lens assembly 7 includes a stop ST7, a first lens L71, a reflective element P7, a second lens L72, a third lens L73, a fourth lens L74, and an optical filter OF7, all of which are arranged in order from an object side to an image side along an optical axis OA7. The reflective element P7 includes an incident surface S74, a reflective surface S75, and an exit surface S76, wherein the incident surface S74 and the exit surface S76 are perpendicular to each other. The reflective surface S75 may contains a metal layer, such as a metal thin film layer of aluminum (Al), silver (Ag), etc., and the reflective surface S75 can be made to include metal layer in any suitable ways, s as coating a metal thin film layer. In this way, the color shift phenomenon and the occurrence of halo during imaging can be avoided, so that the color shift can be effectively improved, the point light source can be effectively concentrated, and has a good image quality for the lens assembly 7. In operation, the light from the object side is reflected by the reflective surface S75 to change the propagation direction and imaged on an image plane IMA7. The image plane IMA7 and the exit surface S76 are parallel to each other. In the seventh embodiment, the reflective element takes a prism as an example but is not limited thereto. For example, the reflective element may be a reflective mirror which only includes a reflective surface.

According to paragraphs [0079]-[0086], wherein: the first lens L71 is a meniscus lens, wherein the object side surface S72 is a concave surface; the second lens L72 is a biconcave lens, wherein the image side surface S78 is a concave surface; the third lens L73 is a biconvex lens, wherein the image side surface S710 is a convex surface and both of the object side surface S709 and image side surface S710 are aspheric surfaces; the fourth lens L74 is a meniscus lens with negative refractive power and made of glass or plastic material, wherein the object side surface S711 is a convex surface and the object side surface S711 is an aspheric surface; and both of the object side surface S713 and image side surface S714 of the optical filter OF7 are plane surfaces.

With the above design of the lenses, reflective element P7, stop ST7, and at least any one of the conditions (1)-(20) satisfied, the lens assembly 7 can have an effective shortened total lens length, an effective increased resolution, an effective corrected aberration, and is capable of an effective corrected chromatic aberration.

Table 19 shows the optical specification of the lens assembly 7 in FIG. 13.

TABLE 19

Effective Focal Length = 2.688 mm F-number = 2.48

Total Optical System Length = 6.990387 mm Field of View = 37.15 degrees

Radius of

Effective

Surface
Curvature
Thickness

Focal Length

Number
(mm)
(mm)
Nd
Vd
(mm)
Remark

S71
∞
0.11165

Stop ST7

S72
−2.17683
0.861726
1.85605
40.2822
2.936058
The First

Lens L71

S73
−1.3829
0.011817

S74
∞
1.511484
2.003303
28.31998

Reflective

Element P7

Incident Surface

S75
∞
1.511484
2.003303
28.31998

Reflective

Element P7

Reflective

Surface

S76
∞
0.1053

Reflective

Element P7

Exit Surface

S77
−3.3371
0.2971
1.651
19.24
−2.580873
The Second

Lens L72

S78
3.5698
0.0243

S79
3.2047
1.4424
1.5352
56.11
1.537502
The Third

Lens L73

S710
−0.9372
0.0128

S711
1.2686
0.307
1.671
19.23991
−2.804457
The Fourth

Lens L74

S712
0.6863
0.4689

S713
∞
0.145
1.5
60

Optical Filter

OF7

S714
∞
0.179424

The definition of aspheric surface sag z of each aspheric lens in table 19 is the same as that of in Table 16, and is not described here again.

In the seventh embodiment, the conic constant k and the aspheric coefficients A, B, C, D, E, F, G, H, I of each aspheric lens are shown in Table 20.

TABLE 20

Surface

A
B
C
D

Number
k
F
G
H
I
E

S72
12.37051
0.048262563
0.389555332
−1.145030981
−3.704327987
69.06398288

−78.86702201
−873.1214579
3076.709194
−2494.305293

S73
0.997786
0.04991879
0.080225825
−0.189381455
0.391873143
−0.055996169

−0.897002003
2.39169789
−0.957068478
−2.717302478

S77
2.316024
−0.0685
−0.0332
0.0216
0.0136
−0.0064636

−0.0057684
0.00085384
0.0019887
−0.00058658

S78
−0.65583
0.0424
−0.0359
−0.006035
0.0073692
0.0029372

−0.000059262
−0.00091777
−0.00026251
0.00017107

S79
−23.3047
−0.0221
0.027
−0.0186
−0.0087938
0.0030024

0.0056237
−0.00037447
−0.001833
0.00048667

S710
−3.44257
−0.0236
0.0207
−0.00061085
−0.0038854
−0.0038854

−0.00062128
0.00048696
0.0002905
−0.00010395

S711
−8.14832
0.0877
−0.00088187
−0.0078454
0.00092888
−0.00090514

0.00028164
0.00019802
0.000021087
−0.000020786

S712
−3.68024
0.0877
−0.00088187
−0.0078454
0.00092888
0.00038536

−0.000055828
−0.000010893
2.2467E−06
−1.005E−07

Table 21 shows the parameters and condition values for conditions (1)-(2), (5)-(6), (8), and (13)-(19) in accordance with the seventh embodiment of the invention. It can be seen from Table 21 that the lens assembly 7 of the seventh embodiment satisfies the conditions (1)-(2), (5)-(6), (8), and (13)-(19).

TABLE 21

L
2.385027
mm
ALOD
9.74
mm
f_obj1
2.936058
mm

f_obj3
1.537502
mm
f_obj4
−2.804457
mm
L1T
0.861726
mm

L1SD
0.67
mm
R₁₁
−2.17683
mm
M1T
1.52330112
mm

TTL/f
2.955357
TTL/ALOD
0.815606
(TTL + f)/f_obj1
3.621253

f_obj3/f_obj4
−0.54807
L1T × L1SD
0.577356
mm²
L1T × R₁₁
−1.87583
mm²

f_obj1/L1T
3.407116
mm
M1T/L1T
1.76773
TTL/L
3.33078

L/f
0.887287

By the above arrangements of the lenses, reflective element P7, and stop ST7, the lens assembly 7 of the seventh embodiment can meet the requirements of optical performance as seen in FIGS. 14A-14C.

It can be seen from FIG. 14A that the field curvature of tangential direction and sagittal direction in the lens assembly 7 of the seventh embodiment ranges from −0.05 mm to 0.03 mm. It can be seen from FIG. 14B that the distortion in the lens assembly 7 of the seventh embodiment ranges from 0% to 2%. It can be seen from FIG. 14C that the modulation transfer function of tangential direction and sagittal direction in the lens assembly 7 of the seventh embodiment ranges from 0.42 to 1.0.

It is obvious that the field curvature and the distortion of the lens assembly 7 of the seventh embodiment can be corrected effectively, and the resolution of the lens assembly 7 of the seventh embodiment can meet the requirement. Therefore, the lens assembly 7 of the seventh embodiment is capable of good optical performance.

Referring to FIG. 15, the lens assembly 8 includes a stop ST8, a first lens L81, a reflective element P8, a second lens L82, a third lens L83, a fifth lens L85, a fourth lens L84, and an optical filter OF8, all of which are arranged in order from an object side to an image side along an optical axis OA8. The reflective element P8 includes an incident surface S84, a reflective surface S85, and an exit surface S86, wherein the incident surface S84 and the exit surface S86 are perpendicular to each other. The reflective surface S85 may contains a metal layer, such as a metal thin film layer of aluminum (Al), silver (Ag), etc., and the reflective surface S85 can be made to include metal layer in any suitable ways, such as coating a metal thin film layer. In this way, the color shift phenomenon and the occurrence of halo during imaging can be avoided, so that the color shift can be effectively improved, the point light source can be effectively concentrated, and has a good image quality for the lens assembly 8. In operation, the light from the object side is reflected by the reflective surface S85 to change the propagation direction and imaged on an image plane IMA8. The image plane IMA8 and the exit surface S86 are parallel to each other. In the eighth embodiment, the reflective element takes a prism as an example but is not limited thereto. For example, the reflective element may be a reflective mirror which only includes a reflective surface.

According to paragraphs [0079]-[0086], wherein: the first lens L81 is a meniscus lens, wherein the object side surface S82 is a concave surface; the second lens L82 is a biconcave lens, wherein the image side surface S88 is a concave surface; the third lens L83 is a biconvex lens, wherein the image side surface S810 is a convex surface and both of the object side surface S809 and image side surface S810 are aspheric surfaces; the fifth lens L85 is a biconvex lens with positive refractive power and made of glass or plastic material, wherein the object side surface S811 is a convex surface, the image side surface S812 is a convex surface, and both of the object side surface S811 and image side surface S812 are aspheric surfaces; the fourth lens L84 is a meniscus lens with positive refractive power and made of glass or plastic material, wherein the object side surface S813 is a convex surface and the object side surface S813 is an aspheric surface; and both of the object side surface S815 and image side surface S816 of the optical filter OF8 are plane surfaces.

With the above design of the lenses, reflective element P8, stop ST8, and at least any one of the conditions (1)-(20) satisfied, the lens assembly 8 can have an effective shortened total lens length, an effective increased resolution, an effective corrected aberration, and is capable of an effective corrected chromatic aberration.

Table 22 shows the optical specification of the lens assembly 8 in FIG. 15.

TABLE 22

Effective Focal Length = 1.118 mm F-number = 2.48

Total Optical System Length = 5.572 mm Field of View = 36.473 degrees

Radius of

Effective

Surface
Curvature
Thickness

Focal Length

Number
(mm)
(mm)
Nd
Vd
(mm)
Remark

S81
∞
0.076

Stop ST8

S82
−1.061
1.056
1.86
40.3
2.398
The First

Lens L81

S83
−1.025
0.020

S84
∞
0.925
2.00
28.3

Reflective

Element P8

Incident Surface

S85
∞
0.925
2.00
28.3

Reflective

Element P8

Reflective

Surface

S86
∞
0.020

Reflective

Element P8

Exit Surface

S87
−6.728
0.210
1.67
19.2
−1.573
The Second

Lens L82

S88
1.283
0.024

S89
1.426
0.718
1.54
56.1
1.898
The Third

Lens L83

S810
−2.941
0.020

S811
6.313
0.610
1.54
56.1
1.815
The Fifth

Lens L85

S812
−1.114
0.020

S813
1.501
0.210
1.67
19.200
11.588
The Fourth

Lens L84

S814
1.751
0.200

S815
∞
0.145
1.5
64.2

Optical Filter

OF8

S816
∞
0.393

The definition of aspheric surface sag z of each aspheric lens in table 22 is the same as that of in Table 16, and is not described here again.

In the eighth embodiment, the conic constant k and the aspheric coefficients A, B, C, D, E, F, G, H, I of each aspheric lens are shown in Table 23.

TABLE 23

Surface

A
B
C
D

Number
k
F
G
H
I
E

S82
1.14E+01
2.00E+00
−6.32E+01
3.22E+03
−5.78E+04
−9.53E+04

1.30E+07
1.19E+08
−6.22E+09
4.68E+10

S83
1.12E+00
1.18E−01
6.40E+00
−5.46E+01
5.95E+01
1.85E+03

−3.45E+03
−7.98E+04
4.66E+05
−7.63E+05

S87
−6.04E+01
−3.87E−01
2.54E−01
3.38E−01
−2.42E−01
−8.21E−01

−1.34E−01
1.55E+00
−1.36E−01
−6.10E−01

S88
2.89E−01
2.86E−02
1.67E−01
2.98E−01
−1 18E−01
−7.13E−01

−4.53E−02
7.81E−01
5.01E−01
−6.02E−01

S89
−8.71E−01
−1.15E−02
9.54E−02
−2.77E−01
−1.75E−02
6.66E−02

2.65E−02
1.43E+00
−2.90E+00
1.65E+00

S810
0.00E+00
3.77E−01
−5.98E−01
−1.89E−01
2.21E−01
−3.70E−01

−1.54E−02
−7.37E−01
3.66E+00
−2.47E+00

S811
4.00E+01
−1.03E−01
1.36E−01
−1.72E−01
−2.12E−01
−1.01E−01

6.34E−01
1.30E−01
−1.21E+00
8.56E−01

S812
−5.24E+00
−4.70E−01
3.61E−01
6.64E−01
9.76E−02
−1.17E+00

−2.16E+00
2.99E+00
5.85E−01
−9.94E−01

S813
9.42E−01
8.21E−01
4.03E−01
−3.52E−01
−4.16E−01
−5.14E−01

−1.60E−01
1.02E+00
1.24E+00
−1.49E+00

S814
2.50E−00
1.33E+00
−6.98E−01
−4.07E−01
2.21E−01
3.53E−01

8.33E−01
−1.36E+00
−1.43E+00
2.04E+00

Table 24 shows the parameters and condition values for conditions (1)-(2), (5)-(6), (8), and (13)-(20) in accordance with the eighth embodiment of the invention. It can be seen from Table 24 that the lens assembly 8 of the eighth embodiment satisfies the conditions (1)-(2), (5)-(6), (8), and (13)-(20).

TABLE 24

L
2.001
mm
ALOD
7.832
mm
f_obj1
2.398
mm

f_obj3
1.898
mm
f_obj4
1.815
mm
L1T
1.056
mm

L1SD
0.457
mm
R₁₁
−1.061
mm
M1T
0.945
mm

OD₂
1.79
mm
OD₃
1.89
mm
OD₄
1.89
mm

OD₅
1.78
mm

TTL/f
5.832737
TTL/ALOD
0.83261
(TTL + f)/f_obj1
3.185571

f_obj3/f_obj4
1.04573
L1T × L1SD
0.482592
mm²
L1T × R₁₁
−1.12042
mm²

f_obj1/L1T
2.270833
mm
M1T/L1T
0.89489
TTL/L
3.258871

L/f
1.789803
8 × M1T −
0.05
mm

(OD₂+ OD₃+

OD₄+ OD₅)

By the above arrangements of the lenses, reflective element P8, and stop ST8, the lens assembly 8 of the eighth embodiment can meet the requirements of optical performance as seen in FIGS. 16A-16C.

It can be seen from FIG. 16A that the field curvature of tangential direction and sagittal direction in the lens assembly 8 of the eighth embodiment ranges from −0.4 mm to 0.15 mm. It can be seen from FIG. 16B that the distortion in the lens assembly 8 of the eighth embodiment ranges from 0% to 2.75%. It can be seen from FIG. 16C that the modulation transfer function of tangential direction and sagittal direction in the lens assembly 8 of the eighth embodiment ranges from 0.33 to 1.0.

It is obvious that the field curvature and the distortion of the lens assembly 8 of the eighth embodiment can be corrected effectively, and the resolution of the lens assembly 8 of the eighth embodiment can meet the requirement. Therefore, the lens assembly 8 of the eighth embodiment is capable of good optical performance.

Referring to FIG. 17, the lens assembly 9 includes a stop ST9, a first lens L91, a reflective element P9, a second lens L92, a third lens L93, a sixth lens L96, a fifth lens L95, a fourth lens L94, and an optical filter OF9, all of which are arranged in order from an object side to an image side along an optical axis OA9. The reflective element P9 includes an incident surface S94, a reflective surface S95, and an exit surface S96, wherein the incident surface S94 and the exit surface S96 are perpendicular to each other. The reflective surface S95 may contains a metal layer, such as a metal thin film layer of aluminum (Al), silver (Ag), etc., and the reflective surface S95 can be made to include metal layer in any suitable ways, such as coating a metal thin film layer. In this way, the color shift phenomenon and the occurrence of halo during imaging can be avoided, so that the color shift can be effectively improved, the point light source can be effectively concentrated, and has a good image quality for the lens assembly 9. In operation, the light from the object side is reflected by the reflective surface S95 to change the propagation direction and imaged on an image plane IMA9. The image plane IMA9 and the exit surface S96 are parallel to each other. In the ninth embodiment, the reflective element takes a prism as an example but is not limited thereto. For example, the reflective element may be a reflective mirror which only includes a reflective surface.

According to paragraphs [0079]-[0086], wherein: the first lens L91 is a meniscus lens, wherein the object side surface S92 is a concave surface; the second lens L92 is a biconcave lens, wherein the image side surface S98 is a concave surface; the third lens L93 is a biconvex lens, wherein the image side surface S910 is a convex surface and both of the object side surface S909 and image side surface S910 are aspheric surfaces; the sixth lens L96 is a meniscus lens with negative refractive power and made of glass or plastic material, wherein the object side surface S911 is a concave surface, the image side surface S912 is a convex surface, and both of the object side surface S911 and image side surface S912 are aspheric surfaces; the fifth lens L95 is a meniscus lens with positive refractive power and made of glass or plastic material, wherein the object side surface S913 is a concave surface, the image side surface S914 is a convex surface, and both of the object side surface S913 and image side surface S914 are aspheric surfaces; the fourth lens L94 is a meniscus lens with positive refractive power and made of glass or plastic material, wherein the object side surface S915 is a convex surface and the object side surface S915 is an aspheric surface; and both of the object side surface S917 and image side surface S918 of the optical filter OF9 are plane surfaces.

With the above design of the lenses, reflective element P9, stop ST9, and at least any one of the conditions (1)-(20) satisfied, the lens assembly 9 can have an effective shortened total lens length, an effective increased resolution, an effective corrected aberration, and is capable of an effective corrected chromatic aberration.

Table 25 shows the optical specification of the lens assembly 9 in FIG. 17.

TABLE 25

Effective Focal Length = 1.082 mm F-number = 2.48

Total Optical System Length = 6.099 mm Field of View = 37.489 degrees

Radius of

Effective

Surface
Curvature
Thickness

Focal Length

Number
(mm)
(mm)
Nd
Vd
(mm)
Remark

S91
∞
0.077

Stop ST9

S92
−0.934
1.078
1.9
40.3
2.74
The First

Lens L91

S93
−1.028
0.030

S94
∞
0.996
2.0
28.3

Reflective

Element P9

Incident

Surface

S95
∞
0.996
2.0
28.3

Reflective

Element P9

Reflective

Surface

S96
∞
0.020

Reflective

Element P9

Exit Surface

S97
−39.255
0.205
1.7
19.2
−3.469
The Second

Lens L92

S98
2.506
0.020

S99
3.433
0.818
1.5
56.1
3.15
The Third

Lens L93

S910
−3.058
0.020

S911
−7.805
0.212
1.7
19.2
−204.946
The Sixth

Lens L96

S912
−8.360
0.020

S913
−11.948
0.526
1.5
56.1
5.855
The Fifth

Lens L95

S914
−2.527
0.020

S915
0.928
0.441
1.5
56.1
2.091
The Fourth

Lens L94

S916
4.453
0.200

S917
∞
0.145
1.5
64.2

Optical

Filter

OF9

S918
∞
0.275

The definition of aspheric surface sag z of each aspheric lens in table 25 is the same as that of in Table 16, and is not described here again.

In the ninth embodiment, the conic constant k and the aspheric coefficients A, B, C, D, E, F, G, H, I of each aspheric lens are shown in Table 26.

TABLE 26

Surface

A
B
C
D

Number
k
F
G
H
I
E

S92
7.05E+00
2.00E+00
−6.32E+01
3.22E+03
−5.78E+04
−9.53E+04

1.30E+07
1.19E+08
−6.22E+09
4.68E+10

S93
1.30E+00
1.18E−01
6.40E+00
−5.46E+01
5.95E+01
1.85E+03

−3.45E+03
−7.98E+04
4.66E+05
−7.63E+05

S97
−1.95E+04
−3.87E−01
2.54E−01
3.38E−01
−2.42E−01
−8.21E−01

−1.34E−01
1.55E+00
−1.36E−01
−6.10E−01

S98
4.61E+00
2.86E−02
1.67E−01
2.98E−01
−1.18E−01
−7.13E−01

−4.53E−02
7.81E−01
5.01E−01
−6.02E−01

S99
−3.37E+01
−1.15E−02
9.54E−02
−2.77E−01
−1.75E−02
6.66E−02

2.65E−02
1.43E+00
−2.90E+00
1.65E+00

S910
−3.16E−01
3.77E−01
−5.98E−01
−1.89E−01
2.21E−01
−3.70E−01

−1.54E−02
−7.37E−01
3.66E+00
−2.47E+00

S911
0.00E+00
−1.03E−01
1.36E−01
−1.72E−01
−2.12E−01
−1.01E−01

6.34E−01
1.30E−01
−1.21E+00
8.56E−01

S912
0.00E+00
−4.70E−01
3.61E−01
6.64E−01
9.76E−02
−1.17E+00

−2.16E+00
2.99E+00
5.85E−01
−9.94E−01

S913
0.00E+00
−1.03E−01
1.36E−01
−1.72E−01
−2.12E−01
−1.01E−01

6.34E−01
1.30E−01
−1.21E+00
8.56E−01

S914
1.69E+00
−4.70E−01
3.61E−01
6.64E−01
9.76E−02
−1.17E+00

−2.16E+00
2.99E+00
5.85E−01
−9.94E−01

S915
−1.50E+00
8.21E−01
4.03E−01
−3.52E−01
−4.16E−01
−5.14E−01

−1.60E−01
1.02E+00
1.24E+00
−1.49E+00

S916
0.00E+00
1.33E+00
−6.98E−01
−4.07E−01
2.21E−01
3.53E−01

8.33E−01
−1.36E+00
−1.43E+00
2.04E+00

Table 27 shows the parameters and condition values for conditions (1)-(2), (5)-(6), (8), and (13)-(20) in accordance with the ninth embodiment of the invention. It can be seen from Table 27 that the lens assembly 9 of the ninth embodiment satisfies the conditions (1)-(2), (5)-(6), (8), and (13)-(20).

TABLE 27

L
2.104
mm
ALOD
10.363
mm
f_obj1
2.74
mm

f_obj3
3.15
mm
f_obj4
−204.949
mm
L1T
1.078
mm

L1SD
0.48585
mm
R₁₁
−0.934
mm
M1T
1.026
mm

OD₂
1.99
mm
OD₃
2
mm
OD₄
1.99
mm

OD₅
2
mm

TTL/f
6.513863
TTL/ALOD
0.680112
(TTL + f)/f_obj1
2.967153

f_obj3/f_obj4
−0.01537
L1T × L1SD
0.523746
mm²
L1T × R₁₁
−1.00685
mm²

f_obj1/L1T
2.541744
mm
M1T/L1T
0.95176
TTL/L
3.34981

L/f
1.944547
8 × M1T −
−0.012
mm

(OD₂+ OD₃+

OD₄+ OD₅)

By the above arrangements of the lenses, reflective element P9, and stop ST9, the lens assembly 9 of the ninth embodiment can meet the requirements of optical performance as seen in FIGS. 18A-18C.

It can be seen from FIG. 18A that the field curvature of tangential direction and sagittal direction in the lens assembly 9 of the ninth embodiment ranges from −0.06 mm to 0.09 mm. It can be seen from FIG. 18B that the distortion in the lens assembly 9 of the ninth embodiment ranges from 0% to 4%. It can be seen from FIG. 18C that the modulation transfer function of tangential direction and sagittal direction in the lens assembly 9 of the ninth embodiment ranges from 0.33 to 1.0.

It is obvious that the field curvature and the distortion of the lens assembly 9 of the ninth embodiment can be corrected effectively, and the resolution of the lens assembly 9 of the ninth embodiment can meet the requirement. Therefore, the lens assembly 9 of the ninth embodiment is capable of good optical performance.

Referring to FIG. 19, the lens assembly 10 includes a fifth lens L105, a stop ST10, a first lens L101, a second lens L102, a third lens L103, a fourth lens L104, and an optical filter OF10, all of which are arranged in order from an object side to an image side along an optical axis OA10. In operation, the light from the object side is imaged on an image plane IMA10.

According to paragraphs [0079]-[0086], wherein: the fifth lens L105 is a meniscus lens with positive refractive power and made of glass or plastic material, wherein the object side surface S101 is a convex surface, the image side surface S102 is a concave surface, and both of the object side surface S101 and image side surface S102 are spherical surfaces; the first lens L101 is a meniscus lens, wherein the object side surface S104 is a concave surface and the image side surface S105 is a convex surface; the second lens L102 is a meniscus lens, wherein the object side surface S106 is a concave surface and the image side surface S107 is a convex surface; the third lens L103 is a biconvex lens, wherein the image side surface S109 is a convex surface and both of the object side surface S108 and image side surface S109 are spherical surfaces; the fourth lens L104 is a meniscus lens with negative refractive power and made of glass or plastic material, wherein the object side surface S1010 is a convex surface, the image side surface S1011 is a concave surface, and the object side surface S1010 is an aspheric surface; and both of the object side surface S1012 and image side surface S1013 of the optical filter OF10 are plane surfaces.

With the above design of the lenses, stop ST10, and at least any one of the conditions (21)-(29) satisfied, the lens assembly 10 can have an effective shortened total lens length, an effective increased resolution, an effective resisted environmental temperature change, an effective corrected aberration, and is capable of an effective corrected chromatic aberration.

If the value Nd₅of condition (24) is less than 1.9, the ability to control the optical effective diameter of the lens is decreased, so that the value of Nd₅must at least greater than or equal to 1.9. The best range of Nd₅is to satisfy the condition: 2.2≥Nd₅≥1.9. When the condition (28): 2.2≥Nd₅≥1.9 is satisfied, the lens assembly can be effectively miniaturized.

Table 28 shows the optical specification of the lens assembly 10 in FIG. 19.

TABLE 28

Effective Focal Length = 5.80646 mm F-number = 2.0

Total Lens Length = 8.55 mm Field of View = 55.00 degrees

Radius of

Effective

Surface
Curvature
Thickness

Focal Length

Number
(mm)
(mm)
Nd
Vd
(mm)
Remark

S101
3.95894
1.18417
1.945958
17.9439
7.133563
The Fifth

Lens L105

S102
8.82867
0.40544

S103
∞
0.53815

Stop ST10

S104
−9.44949
0.32834
1.54392
55.9512
38.817584
The First

Lens L101

S105
−6.57127
1.44769

S106
−1.41906
0.70612
1.66143
20.3729
−35.070688
The Second

Lens L102

S107
−0.55294
0.04721

S108
7.90347
1.44236
1.94596
17.9439
6.039579
The Third

Lens L103

S109
−16.02125
0.11366

S1010
4.57526
0.53893
1.66143
20.3729
−8.387423
The Fourth

Lens L104

S1011
2.34787
0.55401

S1012
∞
0.70043
1.51680
64.2124

Optical Filter

OF10

S1013
∞
0.54413

The definition of aspheric surface sag z of each aspheric lens in table 28 is the same as that of in Table 1, and is not described here again.

In the tenth embodiment, the conic constant k and the aspheric coefficients A, B, C, D, E, F, G of each aspheric lens are shown in Table 29.

TABLE 29

Surface

A
B
C

Number
k
E
F
G
D

S104
−201.36061
−0.038636149
0.020413122
−0.013355429
0.000050272

−0.000758228
0.002640600
−0.001183207

S105
−1.53417
−0.012580526
−0.003289361
−0.003195349
−0.001134968

0.000197044
0.000656148
−0.000357008

S106
−0.47215
0.017040780
0.001459691
−0.000672766
0.000419733

0.000364050
−0.000321983
0.000066342

S107
−1.10421
0.003023939
−0.001248133
0.000661656
0.000008801

−0.000011219
−0.000000121
0.000000344

S1010
−26.68405
−0.017531115
0.000030348
0.000256838
−0.000010924

−0.000001929
0.000000084
0.000000005

S1011
−6.45372
−0.014760078
0.001344553
−0.000149720
0.000019749

−0.000000548
−0.000000163
0.000000011

Table 30 shows the parameters and condition values for conditions (21)-(29) in accordance with the tenth embodiment of the invention. It can be seen from Table 30 that the lens assembly 10 of the tenth embodiment satisfies the conditions (21)-(29).

TABLE 30

D
2.9 mm
L5T
1.18417 mm
E
0.808552 mm

TCE
6 × 10⁻⁶/° C.
L5T/E
1.46

By the above arrangements of the lenses and stop ST10, the lens assembly 10 of the tenth embodiment can meet the requirements of optical performance as seen in FIGS. 20A-20C.

It can be seen from FIG. 20A that the field curvature of tangential direction and sagittal direction in the lens assembly 10 of the tenth embodiment ranges from −0.03 mm to 0.05 mm. It can be seen from FIG. 20B that the distortion in the lens assembly 10 of the tenth embodiment ranges from 0% to 2.5%. It can be seen from FIG. 20C that the modulation transfer function of tangential direction and sagittal direction in the lens assembly 10 of the tenth embodiment ranges from 0.66 to 1.0.

It is obvious that the field curvature and the distortion of the lens assembly 10 of the tenth embodiment can be corrected effectively, and the resolution of the lens assembly 10 of the tenth embodiment can meet the requirement. Therefore, the lens assembly 10 of the tenth embodiment is capable of good optical performance.

Referring to FIG. 21, the lens assembly 11 includes a fifth lens L115, a stop ST11, a first lens L111, a second lens L112, a third lens L113, a fourth lens L114, and an optical filter OF11, all of which are arranged in order from an object side to an image side along an optical axis OA11. In operation, the light from the object side is imaged on an image plane IMA11.

According to paragraphs [0079]-[0086], wherein: the fifth lens L115 is a meniscus lens with positive refractive power and made of glass or plastic material, wherein the object side surface S111 is a convex surface, the image side surface S112 is a concave surface, and both of the object side surface S111 and image side surface S112 are spherical surfaces; the first lens L111 is a meniscus lens, wherein the object side surface S114 is a concave surface; the second lens L112 is a meniscus lens, wherein the image side surface S117 is a convex surface; the third lens L113 is a biconvex lens, wherein the image side surface S119 is a convex surface and both of the object side surface S118 and image side surface S119 are spherical surfaces; the fourth lens L114 is a meniscus lens with negative refractive power and made of glass or plastic material, wherein the object side surface S1110 is a convex surface and the object side surface S1110 is an aspheric surface; and both of the object side surface S1112 and image side surface S1113 of the optical filter OF11 are plane surfaces.

With the above design of the lenses, stop ST11, and at least any one of the conditions (21)-(29) satisfied, the lens assembly 11 can have an effective shortened total lens length, an effective increased resolution, an effective resisted environmental temperature change, an effective corrected aberration, and is capable of an effective corrected chromatic aberration.

If the value Vd₅of condition (27) is greater than 20, the ability of chromatic aberration correction of the fifth lens L115 is reduced, so that the value of Vd₅must at least less than 20. The best range of Vd₅is to satisfy the condition: 17<Vd₅<20. When the condition (29): 17<Vd₅<20 is satisfied, the chromatic aberration of the lens assembly can be effectively decreased.

Table 31 shows the optical specification of the lens assembly 11 in FIG. 21.

TABLE 31

Effective Focal Length = 5.81 mm F-number = 2.0

Total Lens Length = 9.04 mm Field of View = 55.038 degrees

Radius of

Effective

Surface
Curvature
Thickness

Focal Length

Number
(mm)
(mm)
Nd
Vd
(mm)
Remark

S111
4.107088
1.266335
1.945958
17.9439
7.22427
The Fifth

Lens L115

S112
9.482251
0.336351

S113
∞
0.54772

Stop ST11

S114
−9.47203
0.40629
1.543915
55.9512
33.33143
The First

Lens L111

S115
−6.2767
1.390833

S116
−1.3996
0.733813
1.661342
20.3729
−20.3528
The Second

Lens L112

S117
−1.88921
0.047214

S118
7.524683
1.96791
1.945958
17.9439
6.044728
The Third

Lens L113

S119
−17.3496
0.112765

S1110
4.458774
0.548079
1.661342
20.3729
−9.54765
The Fourth

Lens L114

S1111
2.446003
0.476435

S1112
∞
0.700425
1.516797
64.2124

Optical Filter

OF11

S1113
∞
0.508777

The definition of aspheric surface sag z of each aspheric lens in table 31 is the same as that of in Table 16, and is not described here again.

In the eleventh embodiment, the conic constant k and the aspheric coefficients A, B, C, D, E, F, G of each aspheric lens are shown in Table 32.

TABLE 32

Surface

A
B
C

Number
k
E
F
G
D

S114
−198.99125
−0.039080575
0.020841812
−0.01229672
0.000197748

−0.001131297
0.002470088
−0.001038633

S115
0.97126
−0.014389127
−0.001441984
−0.00298736
−0.001406179

0.000106232
0.000679002
0.000314135

S116
−0.47308
0.013078311
0.000608593
−0.000288588
0.000474103

0.00035647
−0.000323491
6.84E−05

S117
−1.01146
0.001487229
−0.000977573
0.000640356
2.96E−06

−6.95E−06
8.66E−07
2.91E−08

S1110
−22.98041
−0.017388991
−3.67E−05
0.000248808
−1.06E−05

−1.76E−06
9.80E−08
2.45E−09

S1111
−6.24639
−0.014596958
0.001317709
−0.000149159
2.00E−05

−5.18E−07
−1.64E−07
1.05E−08

Table 33 shows the parameters and condition values for conditions (21)-(29) in accordance with the eleventh embodiment of the invention. It can be seen from Table 32 that the lens assembly 11 of the eleventh embodiment satisfies the conditions (21)-(29).

TABLE 33

D
2.9029 mm
L5T
1.266335 mm
E
0.897992 mm

TCE
6 × 10⁻⁶/° C.
L5T/E
1.41

By the above arrangements of the lenses and stop ST11, the lens assembly 11 of the eleventh embodiment can meet the requirements of optical performance as seen in FIGS. 22A-22C.

It can be seen from FIG. 22A that the field curvature of tangential direction and sagittal direction in the lens assembly 11 of the eleventh embodiment ranges from −0.04 mm to 0.05 mm. It can be seen from FIG. 22B that the distortion in the lens assembly 11 of the eleventh embodiment ranges from 0% to 1.6%. It can be seen from FIG. 22C that the modulation transfer function of tangential direction and sagittal direction in the lens assembly 11 of the eleventh embodiment ranges from 0.67 to 1.0.

It is obvious that the field curvature and the distortion of the lens assembly 11 of the eleventh embodiment can be corrected effectively, and the resolution of the lens assembly 11 of the eleventh embodiment can meet the requirement. Therefore, the lens assembly 11 of the eleventh embodiment is capable of good optical performance.

Referring to FIG. 23, the lens assembly 12 includes a fifth lens L125, a stop ST12, a first lens L121, a second lens L122, a third lens L123, a fourth lens L124, and an optical filter OF12, all of which are arranged in order from an object side to an image side along an optical axis OA12. In operation, the light from the object side is imaged on an image plane IMA12.

According to paragraphs [0079]-[0086], wherein: the fifth lens L125 is a meniscus lens with positive refractive power and made of glass or plastic material, wherein the object side surface S121 is a convex surface, the image side surface S122 is a concave surface, and both of the object side surface S121 and image side surface S122 are spherical surfaces; the first lens L121 is a meniscus lens, wherein the object side surface S124 is a concave surface; the second lens L122 is a meniscus lens, wherein the image side surface S127 is a convex surface; the third lens L123 is a biconvex lens, wherein the image side surface S129 is a convex surface and both of the object side surface S128 and image side surface S129 are spherical surfaces; the fourth lens L124 is a meniscus lens with negative refractive power and made of glass or plastic material, wherein the object side surface S1210 is a convex surface and the object side surface S1210 is an aspheric surface; and both of the object side surface S1212 and image side surface S1213 of the optical filter OF12 are plane surfaces.

With the above design of the lenses, stop ST12, and at least any one of the conditions (21)-(29) satisfied, the lens assembly 12 can have an effective shortened total lens length, an effective increased resolution, an effective resisted environmental temperature change, an effective corrected aberration, and is capable of an effective corrected chromatic aberration.

Table 34 shows the optical specification of the lens assembly 12 in FIG. 23.

TABLE 34

Effective Focal Length = 5.79 mm F-number = 2.0

Total Lens Length = 8.19 mm Field of View = 55.11 degrees

Radius of

Effective

Surface
Curvature
Thickness

Focal Length

Number
(mm)
(mm)
Nd
Vd
(mm)
Remark

S121
3.935692
1.186649
2.001784
19.325
6.802067
The Fifth

Lens L125

S122
8.464791
0.290445

S123
∞
0.540718

Stop ST12

S124
−9.00662
0.393322
1.543915
55.9512
39.91597
The First

Lens L121

S125
−6.42959
1.375738

S126
−1.40571
0.385239
1.661342
20.3729
−28.6481
The Second

Lens L122

S127
−1.88118
0.047214

S128
8.423747
1.549774
1.945958
17.9439
6.274073
The Third

Lens L123

S129
−15.7453
0.125701

S1210
5.192829
0.515782
1.661342
20.3729
−8.757644
The Fourth

Lens L124

S1211
2.581012
0.542045

S1212
∞
0.700425
1.516797
64.2124

Optical Filter

OF12

S1213
∞
0.532498

The definition of aspheric surface sag z of each aspheric lens in table 34 is the same as that of in Table 16, and is not described here again.

In the twelfth embodiment, the conic constant k and the aspheric coefficients A, B, C, D, E, F, G of each aspheric lens are shown in Table 35.

TABLE 35

Surface

A
B
C

Number
k
E
F
G
D

S124
−1.8218208
−0.037405167
0.021456633
−0.01302741
0.00016725

−0.000973744
0.00260212
−0.001125216

S125
−2.96846
−0.012075656
−0.002658559
−0.003085045
−0.001291418

0.000126268
0.000654463
−0.000315947

S126
−0.46591
0.017504217
0.000601285
−0.00064421
0.000503056

0.000376188
−0.000331765
6.89E−05

S127
−1.13584
0.003520561
−0.001180144
0.000692902
2.37E−05

−3.75E−06
4.13E−07
−5.39E−08

S1210
−38.45769
−0.017342398
8.55E−05
0.000254963
−1.11E−05

−1.92E−06
8.79E−08
4.42E−09

S1211
−7.91158
−0.01494149
0.001311208
−0.000147028
1.99E−05

−5.40E−07
−1.63E−07
1.06E−08

Table 36 shows the parameters and condition values for conditions (21)-(29) in accordance with the twelfth embodiment of the invention. It can be seen from Table 36 that the lens assembly 12 of the twelfth embodiment satisfies the conditions (21)-(29).

TABLE 36

D
2.898295 mm
L5T
1.186649 mm
E
0.841372 mm

TCE
8.4 × 10⁻⁶/° C.
L5T/E
1.41

By the above arrangements of the lenses and stop ST12, the lens assembly 12 of the twelfth embodiment can meet the requirements of optical performance as seen in FIGS. 24A-24C.

It can be seen from FIG. 24A that the field curvature of tangential direction and sagittal direction in the lens assembly 12 of the twelfth embodiment ranges from −0.035 mm to 0.045 mm. It can be seen from FIG. 24B that the distortion in the lens assembly 12 of the twelfth embodiment ranges from 0% to 1.6%. It can be seen from FIG. 24C that the modulation transfer function of tangential direction and sagittal direction in the lens assembly 12 of the twelfth embodiment ranges from 0.67 to 1.0.

It is obvious that the field curvature and the distortion of the lens assembly 12 of the twelfth embodiment can be corrected effectively, and the resolution of the lens assembly 12 of the twelfth embodiment can meet the requirement. Therefore, the lens assembly 12 of the twelfth embodiment is capable of good optical performance.

Referring to FIG. 25, the lens assembly 13 includes a fifth lens L135, a stop ST13, a first lens L131, a second lens L132, a third lens L133, a fourth lens L134, and an optical filter OF13, all of which are arranged in order from an object side to an image side along an optical axis OA13. In operation, the light from the object side is imaged on an image plane IMA13

According to paragraphs [0079]-[0086], wherein: the fifth lens L135 is a meniscus lens with positive refractive power and made of glass or plastic material, wherein the object side surface S131 is a convex surface, the image side surface S132 is a concave surface, and both of the object side surface S131 and image side surface S132 are spherical surfaces; the first lens L131 is a meniscus lens, wherein the object side surface S134 is a concave surface; the second lens L132 is a meniscus lens, wherein the image side surface S137 is a convex surface; the third lens L133 is a biconvex lens, wherein the image side surface S139 is a convex surface and both of the object side surface S138 and image side surface S139 are spherical surfaces; the fourth lens L134 is a meniscus lens with negative refractive power and made of glass or plastic material, wherein the object side surface S1310 is a convex surface and the object side surface S1310 is an aspheric surface; and both of the object side surface S1312 and image side surface S1313 of the optical filter OF13 are plane surfaces.

With the above design of the lenses, stop ST13, and at least any one of the conditions (21)-(29) satisfied, the lens assembly 13 can have an effective shortened total lens length, an effective increased resolution, an effective resisted environmental temperature change, an effective corrected aberration, and is capable of an effective corrected chromatic aberration.

Table 37 shows the optical specification of the lens assembly 13 in FIG. 25.

TABLE 37

Effective Focal Length = 5.79 mm F-number = 2.0

Total Lens Length = 8.41 mm Field of View = 55.086 degrees

Radius of

Effective

Surface
Curvature
Thickness

Focal Length

Number
(mm)
(mm)
Nd
Vd
(mm)
Remark

S131
3.982505
1.124168
2.102999
18.0511
6.472169
The Fifth

Lens L135

S132
8.196364
0.310158

S133
∞
0.530517

Stop ST13

S134
−8.25083
0.389504
1.543915
55.9512
51.8046
The First

Lens L131

S135
−6.46134
1.305865

S136
−1.42388
0.647982
1.661342
20.3729
−22.6349
The Second

Lens L132

S137
−1.85981
0.047214

S138
8.905051
1.68856
1.945958
17.9439
6.593054
The Third

Lens L133

S139
−16.2986
0.133293

S1310
5.385474
0.505013
1.661342
20.3729
−10.0388
The Fourth

Lens L134

S1311
2.812151
0.519068

S1312
∞
0.700425
1.516797
64.2124

Optical Filter

OF13

S1313
∞
0.505963

The definition of aspheric surface sag z of each aspheric lens in table 37 is the same as that of in Table 16, and is not described here again.

In the thirteenth embodiment, the conic constant k and the aspheric coefficients A, B, C, D, E, F, G of each aspheric lens are shown in Table 38.

TABLE 38

Surface

A
B
C

Number
k
E
F
G
D

S134
−149.97542
−0.03621325
0.022298996
−0.012802649
−2.51E−05

−0.000952638
0.002503675
−0.001077983

S135
−5.82246
−0.011093431
−0.002507191
−0.003063226
−0.001511286

0.000125019
0.000666585
−0.000313545

S136
−0.47816
0.01744862
−0.000159595
−0.000539317
0.000456602

0.000394915
−0.000330973
6.50E−05

S137
−1.15720
0.004155917
−0.000756778
0.000776814
3.46E−05

−1.65E−06
3.08E−07
−2.56E−07

S1310
−44.91773
−0.017066787
1.09E−04
0.000252699
−1.13E−05

−1.92E−06
8.88E−08
4.52E−09

S1311
−9.51625
−0.015578827
0.001331543
−0.000148357
1.98E−05

−5.47E−07
−1.63E−07
1.07E−08

Table 39 shows the parameters and condition values for conditions (21)-(29) in accordance with the thirteenth embodiment of the invention. It can be seen from Table 39 that the lens assembly 13 of the thirteenth embodiment satisfies the conditions (21)-(29).

TABLE 39

D
2.9 mm
L5T
1.124168 mm
E
0.796983 mm

TCE
8.4 × 10⁻⁶/° C.
L5T/E
1.41

By the above arrangements of the lenses and stop ST13, the lens assembly 13 of the thirteenth embodiment can meet the requirements of optical performance as seen in FIGS. 26A-26C.

It can be seen from FIG. 26A that the field curvature of tangential direction and sagittal direction in the lens assembly 13 of the thirteenth embodiment ranges from −0.04 mm to 0.035 mm. It can be seen from FIG. 26B that the distortion in the lens assembly 13 of the thirteenth embodiment ranges from 0% to 1.6%. It can be seen from FIG. 26C that the modulation transfer function of tangential direction and sagittal direction in the lens assembly 13 of the thirteenth embodiment ranges from 0.66 to 1.0.

It is obvious that the field curvature and the distortion of the lens assembly 13 of the thirteenth embodiment can be corrected effectively, and the resolution of the lens assembly 13 of the thirteenth embodiment can meet the requirement. Therefore, the lens assembly 13 of the thirteenth embodiment is capable of good optical performance.

While the invention has been described by way of example and in terms of the preferred embodiment(s), it is to be understood that the invention is not limited thereto. On the contrary, it is intended to cover various modifications and similar arrangements and procedures, and the scope of the appended claims therefore should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements and procedures.

Number	Date	Country	Kind
201910923848.4	Sep 2019	CN	national
108139552	Oct 2019	TW	national
109107271	Mar 2020	TW	national

Lens Assembly

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Publication Number

Date Filed

Date Published

Inventors

Original Assignees

CPC

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Abstract

Description

Claims

Priority Claims (3)