Patent Application
20250155677
The present disclosure relates to a zoom lens and an imaging apparatus.
In recent years, a zoom lens used in an imaging apparatus has been required to have high optical performance in an entire zoom range as well as to be miniaturized and have a wide angle of view in association with higher functionality of the imaging apparatus. As a small zoom lens relatively easily made to have a wider angle, a negative-lead zoom lens has been known in which a lens group of negative refractive power precedes (a lens group of negative refractive power is positioned on a side closest to an object) (see PTLs 1 and 2).
In configurations proposed in PTLs 1 and 2, it is difficult to have high optical performance in an entire zoom range and to achieve miniaturization and a wider angle of view.
It is desirable to provide a zoom lens that has high optical performance in an entire zoom range and that enables achievement in miniaturization and a wider angle of view, and an imaging apparatus including such a zoom lens.
A zoom lens according to an embodiment of the present disclosure includes, in order from a side of an object toward a side of an image plane: a first lens group having negative refractive power; a second lens group; a third lens group having positive refractive power; and a fourth lens group having negative refractive power, in which an interval between adjacent lens groups varies upon zooming, and the second lens group is fixed upon the zooming.
An imaging apparatus according to an embodiment of the present disclosure includes: a zoom lens; and an imaging element that outputs an imaging signal corresponding to an optical image formed by the zoom lens, and the zoom lens is configured by the zoom lens according to an embodiment of the present disclosure.
In the zoom lens or imaging apparatus according to an embodiment of the present disclosure, the configurations of the respective lens groups are optimized to enable high optical performance in an entire zoom range and achievement in miniaturization and a wider angle of view.
Hereinafter, description is given in detail of embodiments of the present disclosure with reference to the drawings. It is to be noted that the description is given in the following order.
As a negative-lead zoom lens, PTL 1 (Japanese Unexamined Patent Application Publication No. 2015-34892) discloses a zoom lens including first to fourth lens groups of negative, positive, negative, and positive refractive power disposed in order from an object side to an image plane side. In addition, PTL 2 (Japanese Unexamined Patent Application Publication No. 2019-8031) discloses a zoom lens including first to fifth lens groups of negative, positive, positive, negative, and positive refractive power disposed in order from the object side to the image plane side.
The negative-lead zoom lens has an asymmetric lens configuration, and thus has difficulty in correcting various aberrations, making it difficult to obtain high optical performance while achieving miniaturization. For example, in the negative-lead zoom lens, as in the configuration examples proposed in PTLs 1 and 2, light at an intermediate image height enters in an unnecessarily large amount between a stop and the first lens group of negative refractive power at a wide-angle end, which makes it difficult to correct aberrations and further results in an increase in size and weight. It is therefore important to appropriately set an amount of light at an intermediate image height to a peripheral image height, in order to obtain high optical performance in an entire zoom range while achieving miniaturization and a wider angle of view.
In
Hereinafter, description is given of a configuration of the zoom lens according to an embodiment of the present disclosure, as appropriate, in association with the zoom lenses 1 to 5 according to the respective configuration examples illustrated in
A zoom lens according to an embodiment includes a plurality of lens groups. The plurality of lens groups includes, in order from the object side toward the image plane side, at least a first lens group G1 having negative refractive power, a second lens group G2, a third lens group G3 having positive refractive power, and a fourth lens group G4 having negative refractive power. In addition, an aperture stop St may be disposed on a side closer to the image plane than the second lens group G2.
In the zoom lens according to an embodiment, upon zooming from a wide-angle end to a telephoto end, an interval between adjacent lens groups varies, and the second lens group G2 is fixed upon the zooming. It is to be noted that
In addition to those described above, the zoom lens according to an embodiment may further satisfy a predetermined conditional expression or the like described later.
Next, description is given of workings and effects of the zoom lens according to an embodiment of the present disclosure. In addition thereto, description is given of a more preferable configuration in the zoom lens according to an embodiment of the present disclosure as well as of the workings and effects thereof.
It is to be noted that the effects described in herein are merely exemplary and are not limited thereto, and may further include other effects.
According to the zoom lens of an embodiment, the configurations of the respective lens groups are optimized to enable high optical performance in the entire zoom range and achievement in miniaturization and a wider angle of view. This makes it possible to provide a zoom lens that has high optical performance in the entire zoom range and that enables achievement in miniaturization and a wider angle of view, and an imaging apparatus including such a zoom lens.
The zoom lens according to an embodiment includes, in order from the object side toward the image plane side, the first lens group G1 having negative refractive power, the second lens group G2, the third lens group G3 having positive refractive power, and the fourth lens group G4 having negative refractive power, thereby enabling a wide-angle zoom lens to have a miniaturized configuration as a retrofocus power arrangement.
In the zoom lens according to an embodiment, disposing the fixed second lens group G2 upon zooming between the first lens group G1 and the aperture stop St enables an amount of unnecessary light at the intermediate image height to be cut in a well-balanced manner, thus making it possible to obtain higher optical performance.
In addition, in the zoom lens according to an embodiment, a fifth lens group G5 having positive refractive power may be disposed on a side closer to the image plane than the fourth lens group G4 of negative refractive power. This enables retrofocus arrangement in the wide-angle zoom lens as an optical system as a whole, which is more effective for the miniaturization.
In addition, in the zoom lens according to an embodiment, the fourth lens group G4 may be moved as a focus lens group in an optical axis direction upon focusing. Disposing the focus lens group on a side closer to the image plane than the aperture stop St, in particular, disposing the fourth lens group G4 as the focus lens group enables a lens having a relatively light weight and a small diameter to be employed as the focus lens group, thus making it possible to achieve miniaturization and a lighter weight also in the size of a lens barrel.
The zoom lens according to an embodiment may satisfy the following conditional expression (1):
The conditional expression (1) is defined to allow an optical system to be miniaturized and lightweight, and is a conditional expression to appropriately set a relationship between the focal distance of the total system at the wide-angle end and the back focus at the wide-angle end. When falling below the lower limit of the conditional expression (1), the focal distance at the wide-angle end becomes too long, making it difficult to have a wider angle. Meanwhile, when exceeding the upper limit of the conditional expression (1), the back focus becomes too long, thus increasing asymmetry of the power arrangement required for the wider angle. This makes it difficult correct various aberrations, thus making it difficult to achieve higher image quality.
It is to be noted that setting the numerical value range of the conditional expression (1) to that as in the following conditional expression (1A) makes it possible to obtain higher effects.
In addition, the zoom lens according to an embodiment may satisfy the following conditional expression (2):
The conditional expression (2) is defined to allow the optical system to be miniaturized and lightweight, and is a conditional expression to appropriately set the focal distance of the total system at the wide-angle end and the focal distance of the second lens group G2. When exceeding the upper limit of the conditional expression (2), the focal distance of the second lens group G2 becomes too large, and an aberration correction effect becomes weak, resulting in an increase in the size of the optical system. Meanwhile, when falling below the lower limit of the conditional expression (2), the focal distance of the second lens group G2 becomes too small, and an amount of generation of aberrations is increased, thus making it difficult for the optical system to have higher performance.
It is to be noted that setting the numerical value range of the conditional expression (2) to that as in the following conditional expression (2A) makes it possible to obtain higher effects.
In addition, the zoom lens according to an embodiment may satisfy the following conditional expression (3):
The conditional expression (3) is defined to allow the optical system to be miniaturized and lightweight, and is a conditional expression to appropriately set the focal distance of the total system at the wide-angle end and the distance D12 on the optical axis between the first lens group G1 and the second lens group G2 at the wide-angle end. When deviating from the range of the conditional expression (3), it becomes difficult to cut the amount of light at the intermediate image height at the wide-angle end, and an aberration correction effect becomes weak, resulting in an increase in the size of the optical system.
It is to be noted that setting the numerical value range of the conditional expression (3) to that as in the following conditional expression (3A) makes it possible to obtain higher effects.
Next, description is given of an example of application of the zoom lens according to an embodiment of the present disclosure to a specific imaging apparatus.
The camera block 110 serves a role in an imaging function, and includes an imaging lens 111, and an imaging element 112 such as CCD (Charge Coupled Devices) or CMOS (Complementary Metal Oxide Semiconductor). The imaging element 112 converts an optical image formed by the imaging lens 111 into an electric signal, to thereby output an imaging signal (image signal) that corresponds to the optical image. Any of the zoom lenses 1 to 6 according to the respective configuration examples illustrated in
The camera signal processing section 20 performs, on the image signal outputted from the imaging element 112, various types of signal processing including, for example, analog-digital conversion, noise removal, image quality correction, or conversion to luminance and color difference signals.
The image processing section 30 performs processing of recording and reproduction of an image signal. The image processing section 30 performs processing including, for example, compression encoding and expansion decoding processing of an image signal based on a predetermined image data format, and processing of converting data specification such as resolution.
The LCD 40 has a function of displaying various types of data including, for example, a state of operation performed on the input section 70 by a user and a captured image. The R/W 50 performs writing of image data encoded by the image processing section 30 into a memory card 1000, and reading of the image data recorded in the memory card 1000. The memory card 1000 is a semiconductor memory attachable to and detachable from a slot coupled to the R/W 50, for example.
The CPU 60 functions as a control processing section that controls each of circuit blocks provided in the imaging apparatus 100. The CPU 60 controls each of the circuit blocks on the basis of, for example, an instruction input signal from the input section 70. The input section 70 includes, for example, various switches on which required operations are performed by the user. For example, the input section 70 includes a shutter release button used to perform a shutter operation, a selection switch used to select an operation mode, or the like. The input section 70 outputs, to the CPU 60, the instruction input signal that corresponds to the operation performed by the user. The lens drive control section 80 controls driving of lenses disposed in the camera block 110. The lens drive control section 80 controls, for example, unillustrated motors that drive respective lenses of the imaging lens 111 on the basis of a control signal from the CPU 60.
In the following, description is given of operations in the imaging apparatus 100.
In a standby state upon image capturing, an image signal corresponding to an image captured in the camera block 110 is outputted to the LCD 40 through the camera signal processing section 20, and is thus displayed as a camera-through image, under the control of the CPU 60. In addition, for example, when the instruction input signal, for zooming or focusing, from the input section 70 is inputted, the CPU 60 outputs the control signal to the lens drive control section 80. This moves a predetermined lens of the imaging lens 111 under the control of the lens drive control section 80.
When an unillustrated shutter of the camera block 110 is operated in response to the instruction input signal from the input section 70, the captured image signal is outputted from the camera signal processing section 20 to the image processing section 30 to be subjected to the compression encoding processing, and is thus converted into digital data in a predetermined data format. The converted data is outputted to the R/W 50 to be written into the memory card 1000.
It is to be noted that the focusing is performed in a case where the shutter release button of the input section 70 is pressed halfway, or in a case where the shutter release button is pressed fully for recording (image capturing), for example. The focusing is performed by causing the lens drive control section 80 to move a predetermined lens of the imaging lens 111 on the basis of the control signal from the CPU 60.
In a case where the image data recorded in the memory card 1000 is to be reproduced, predetermined image data is read from the memory card 1000 by the R/W 50 in accordance with the operation performed on the input section 70. The predetermined image data read from the memory card 1000 is subjected to the expansion decoding processing by the image processing section 30. Thereafter, a reproduction image signal is outputted to the LCD 40, and a reproduced image is thus displayed.
It is to be noted that, although the foregoing embodiment exemplifies the application of the imaging apparatus to the digital still camera, or the like, a range of application of the imaging apparatus is not limited to the digital still camera. The imaging apparatus is applicable to other various imaging apparatuses. For example, the imaging apparatus is applicable to a digital single-lens reflex camera, a digital non-reflex camera, a digital video camera, a surveillance camera, and the like. In addition, the imaging apparatus is applicable widely to, for example, a camera section of a digital input/output apparatus such as a mobile phone mounted with a camera or an information terminal mounted with a camera. In addition, the imaging apparatus is applicable to an interchangeable-lens camera as well.
Next, description is given of specific Numerical Examples of the zoom lens according to an embodiment of the present disclosure. Here, the description is given of Numerical Examples in which specific unmerical values are applied to the zoom lenses 1 to 5 of the respective configuration examples illustrated in
It is to be noted that meanings, and the like of respective symbols indicated in the following tables and descriptions are as follows. “Si” denotes the number of i-th surface signed to be increased sequentially from the side closest to the object. “ri” denotes a value (mm) of a paraxial radius of curvature of the i-th surface. “di” denotes a value (mm) of an interval on the optical axis between the i-th surface and (i+1)-th surface. “ndi” denotes a value of a refractive index with respect to a d-line (wavelength of 587.6 nm) of a material of an optical element having the i-th surface. “vdi” denotes a value of Abbe number in the d-line of the material of the optical element having the i-th surface. “φi” denotes a value (mm) of an effective diameter of the i-th surface. A portion where the value of “ri” is “∞” indicates a flat surface, an aperture stop surface, or the like. “ASP” in the column of surface number (Si) indicates that the surface is configured by an aspherical shape. “STO” in the column of the surface number indicates that an aperture stop St is disposed at the corresponding position. “OBJ” in the column of the surface number indicates that the surface is an object surface (subject surface). “IMG” in the column of the surface number indicates that the surface is an image plane. “f” denotes a focal distance of the total system (unit: mm). “Fno” denotes an open F-value (F-number). “ω” denotes a half angle of view (unit: °). “Y” denotes an image height (unit: mm). “L” denotes a total optical length (a distance on the optical axis from a surface on the side closest to the object to the image plane IMG) (unit: mm).
In addition, some of the lenses to be used in each of Examples have a lens surface configured by an aspherical surface. The aspheric shape is defined by the following expression. It is to be noted that, in each of the tables exhibiting aspherical coefficients described later, “E-i” denotes exponential notation with a base of 10, i.e., “10−i”; for example, “0.12345E-05” denotes “0.12345×10−5”.
Here, it is assumed that “x” is a distance (a sag amount) from a vertex of a lens surface in the optical axis direction, “y” is a height in a direction perpendicular to the optical axis, “c” is a paraxial curvature at the vertex of the lens surface (inverse of the radius of curvature), and “k” is a conic (conic) constant. A4, A6, A8, A10, and A12 are 4-th order, 6-th order, 8-th order, 10-th order, and 12-th order aspherical coefficients, respectively.
Table 1 exhibits basic lens data of the zoom lens 1 according to Example 1 illustrated in
The zoom lens 1 according to Example 1 has a configuration in which the first lens group G1 to the fifth lens group G5 are disposed in order from the object side toward the image plane side. The aperture stop St is disposed in the third lens group G3.
Upon zooming from the wide-angle end to the telephoto end, an interval between adjacent lens groups varies, and the second lens group G2 is fixed with respect to the image plane IMG upon the zooming. The second lens group G2 serves to cut unnecessary light at the intermediate image height or the like.
Upon focusing when the object distance varies from infinity to a short distance, the fourth lens group G4 moves in the optical axis direction to the image plane side.
The first lens group G1 has negative refractive power. The first lens group G1 includes lenses L11 to L13 in order from the object side toward the image plane side. The lens L11 is a negative meniscus lens with a convex surface opposed to the object side. The lens L12 is a negative meniscus lens with a convex surface opposed to the object side. The lens L13 is a positive meniscus lens with a convex surface opposed to the object side. It is to be noted that resin layers constituting aspherical surfaces (a third surface and a sixth surface) are stacked on a surface of the lens L11 on the image plane side and a surface of the lens L12 on the image plane side.
The second lens group G2 has negative refractive power. The second lens group G2 includes a lens L21. The lens L21 is a negative meniscus lens with a convex surface opposed to the object side.
The third lens group G3 has positive refractive power. The third lens group G3 includes, in order from the object side toward the image plane side, a lens L31, a lens L32, the aperture stop St. and lenses L33 to L35. The lens L31 is a biconvex lens of an aspherical shape. The lens L32 is a negative meniscus lens with a convex surface opposed to the object side. The lens L33 is a negative meniscus lens with a convex surface opposed to the object side. The lens L34 is a positive lens of a biconvex shape. The lens L33 and the lens L34 constitute a cemented lens in which the lens L33 and the lens L34 are attached to each other. The lens L35 is a biconvex lens of an aspherical shape.
The fourth lens group G4 has negative refractive power. The fourth lens group G4 includes a lens L41 and a lens L42 in order from the object side toward the image plane side. The lens L41 is a positive meniscus lens with a convex surface opposed to the image plane side. The lens L42 is a negative lens of a biconcave shape. The lens L41 and the lens L42 constitute a cemented lens in which the lens L41 and the lens L42 are attached to each other.
The fifth lens group G5 has positive refractive power. The fifth lens group G5 includes a lens L51 and a lens L52 in order from the object side toward the image plane side. The lens L51 is a positive lens of a biconvex shape. The lens L52 is a negative lens of an aspherical shape on both sides.
The above-described configuration allows for achievement of miniaturization and alight weight despite a wide angle as well as achievement of a zoom lens with less variation in an angle of view and with less variation in aberration.
These apply similarly to aberration diagrams in subsequent other Examples.
As appreciated from each of the aberration diagrams, the zoom lens 1 according to Example 1 undergoes favorable correction of various aberrations, and thus has superior image-forming performance.
Table 6 exhibits basic lens data of the zoom lens 2 according to Example 2 illustrated in
The zoom lens 2 according to Example 2 has a configuration in which the first lens group G1 to the fifth lens group G5 are disposed in order from the object side toward the image plane side. The aperture stop St is disposed in the third lens group G3.
Upon zooming from the wide-angle end to the telephoto end, an interval between adjacent lens groups varies, and the second lens group G2 is fixed with respect to the image plane IMG upon the zooming. The second lens group G2 serves to cut unnecessary light at the intermediate image height or the like.
Upon focusing when the object distance varies from infinity to a short distance, the fourth lens group G4 moves in the optical axis direction to the image plane side.
The first lens group G1 has negative refractive power. The first lens group G1 includes lenses the L11 to L13 in order from the object side toward the image plane side. The lens L11 is a negative meniscus lens with a convex surface opposed to the object side. The lens L12 is a negative meniscus lens with a convex surface opposed to the object side. The lens L13 is a positive meniscus lens with a convex surface opposed to the object side. It is to be noted that a resin layer constituting an aspherical surface (the third surface) is stacked on a surface of the lens L11 on the image plane side.
The second lens group G2 has positive refractive power. The second lens group G2 includes a lens L21. The lens L21 is a positive meniscus lens with a convex surface opposed to the object side.
The third lens group G3 has positive refractive power. The third lens group G3 includes, in order from the object side toward the image plane side, the lens L31, the lens L32, the aperture stop St. and the lenses L33 to L35. The lens L31 is a biconvex lens of an aspherical shape. The lens L32 is a negative lens of a biconcave shape. The lens L33 is a negative meniscus lens with a convex surface opposed to the object side. The lens L34 is a positive lens of a biconvex shape. The lens L33 and the lens L34 constitute a cemented lens in which the lens L33 and the lens L34 are attached to each other. The lens L35 is a biconvex lens of an aspherical shape.
The fourth lens group G4 has negative refractive power. The fourth lens group G4 includes the lens L41 and the lens L42 in order from the object side toward the image plane side. The lens L41 is a positive meniscus lens with a convex surface opposed to the image plane side. The lens L42 is a negative lens of a biconcave shape. The lens L41 and the lens L42 constitute a cemented lens in which the lens L41 and the lens L42 are attached to each other.
The fifth lens group G5 has positive refractive power. The fifth lens group G5 includes the lens L51 and the lens L52 in order from the object side toward the image plane side. The lens L51 is a positive lens of a biconvex shape. The lens L52 is a negative lens of an aspherical shape on both sides.
The above-described configuration allows for achievement of miniaturization and a light weight despite a wide angle as well as achievement of a zoom lens with less variation in an angle of view and with less variation in aberration.
As appreciated from each of the aberration diagrams, the zoom lens 2 according to Example 2 undergoes favorable correction of various aberrations, and thus has superior image-forming performance.
Table 11 exhibits basic lens data of the zoom lens 3 according to Example 3 illustrated in
The zoom lens 3 according to Example 3 has a configuration in which the first lens group G1 to the fifth lens group G5 are disposed in order from the object side toward the image plane side. The aperture stop St is disposed in the third lens group G3.
Upon zooming from the wide-angle end to the telephoto end, an interval between adjacent lens groups varies, and the second lens group G2 is fixed with respect to the image plane MG upon the zooming. The second lens group G2 serves to cut unnecessary light at the intermediate image height or the like.
Upon focusing when the object distance varies from infinity to a short distance, the fourth lens group G4 moves in the optical axis direction to the image plane side.
The first lens group G1 has negative refractive power. The first lens group G1 includes lenses the L11 to L13 in order from the object side toward the image plane side. The lens L11 is a negative meniscus lens with a convex surface opposed to the object side. The lens L12 is a negative meniscus lens with a convex surface opposed to the object side. The lens L13 is a positive meniscus lens with a convex surface opposed to the object side. It is to be noted that resin layers constituting aspherical surfaces (the third surface and the sixth surface) are stacked on a surface of the lens L11 on the image plane side and a surface of the lens L12 on the image plane side.
The second lens group G2 has negative refractive power. The second lens group G2 includes a lens L21. The lens L21 is a negative meniscus lens with a convex surface opposed to the object side.
The third lens group G3 has positive refractive power. The third lens group G3 includes, in order from the object side toward the image plane side, the lens L31, the lens L32, the aperture stop St. and the lenses L33 to L35. The lens L31 is a biconvex lens of an aspherical shape. The lens L32 is a negative meniscus lens with a convex surface opposed to the object side. The lens L33 is a negative meniscus lens with a convex surface opposed to the object side. The lens L34 is a positive lens of a biconvex shape. The lens L33 and the lens L34 constitute a cemented lens in which the lens L33 and the lens L34 are attached to each other. The lens L35 is a biconvex lens of an aspherical shape.
The fourth lens group G4 has negative refractive power. The fourth lens group G4 includes the lens L41 and the lens L42 in order from the object side toward the image plane side. The lens L41 is a positive lens of a biconvex shape. The lens L42 is a negative lens of a biconcave shape. The lens L41 and the lens L42 constitute a cemented lens in which the lens L41 and the lens L42 are attached to each other.
The fifth lens group G5 has positive refractive power. The fifth lens group G5 includes the lens L51 and the lens L52 in order from the object side toward the image plane side. The lens L51 is a positive lens of a biconvex shape. The lens L52 is a negative lens of an aspherical shape on both sides.
The above-described configuration allows for achievement of miniaturization and a light weight despite a wide angle as well as achievement of a zoom lens with less variation in an angle of view and with less variation in aberration.
As appreciated from each of the aberration diagrams, the zoom lens 3 according to Example 3 undergoes favorable correction of various aberrations, and thus has superior image-forming performance.
Table 16 exhibits basic lens data of the zoom lens 4 according to Example 4 illustrated in
The zoom lens 4 according to Example 4 has a configuration in which the first lens group G1 to the fifth lens group G5 are disposed in order from the object side toward the image plane side. The aperture stop St is disposed in the third lens group G3.
Upon zooming from the wide-angle end to the telephoto end, an interval between adjacent lens groups varies, and the second lens group G2 is fixed with respect to the image plane IMG upon the zooming. The second lens group G2 serves to cut unnecessary light at the intermediate image height or the like.
Upon focusing when the object distance varies from infinity to a short distance, the fourth lens group G4 moves in the optical axis direction to the image plane side.
The first lens group G1 has negative refractive power. The first lens group G1 includes lenses the L11 to L13 in order from the object side toward the image plane side. The lens L11 is a negative meniscus lens with a convex surface opposed to the object side. The lens L12 is a negative meniscus lens with a convex surface opposed to the object side. The lens L13 is a positive meniscus lens with a convex surface opposed to the object side.
The second lens group G2 has positive refractive power. The second lens group G2 includes a lens L21. The lens L21 is a positive meniscus lens with a convex surface opposed to the object side.
The third lens group G3 has positive refractive power. The third lens group G3 includes, in order from the object side toward the image plane side, the lens L31, the lens L32, the aperture stop St. and the lenses L33 to L35. The lens L31 is a positive lens of an aspherical shape. The lens L32 is a negative meniscus lens with a convex surface opposed to the object side. The lens L33 is a negative meniscus lens with a convex surface opposed to the object side. The lens L34 is a positive lens of a biconvex shape. The lens L33 and the lens L34 constitute a cemented lens in which the lens L33 and the lens L34 are attached to each other. The lens L35 is a biconvex lens of an aspherical shape.
The fourth lens group G4 has negative refractive power. The fourth lens group G4 includes the lens L41 and the lens L42 in order from the object side toward the image plane side. The lens L41 is a positive meniscus lens with a convex surface opposed to the image plane side. The lens L42 is a negative lens of a biconcave shape. The lens L41 and the lens L42 constitute a cemented lens in which the lens L41 and the lens L42 are attached to each other.
The fifth lens group G5 has positive refractive power. The fifth lens group G5 includes the lens L51 and the lens L52 in order from the object side toward the image plane side. The lens L51 is a positive lens of a biconvex shape. The lens L52 is a negative lens of an aspherical shape on both sides.
The above-described configuration allows for achievement of miniaturization and a light weight despite a wide angle as well as achievement of a zoom lens with less variation in an angle of view and with less variation in aberration.
As appreciated from each of the aberration diagrams, the zoom lens 4 according to Example 4 undergoes favorable correction of various aberrations, and thus has superior image-forming performance.
Table 21 exhibits basic lens data of the zoom lens 5 according to Example 5 illustrated in
The zoom lens 5 according to Example 5 has a configuration in which the first lens group G1 to the fifth lens group G5 are disposed in order from the object side toward the image plane side. The aperture stop St is disposed in the third lens group G3.
Upon zooming from the wide-angle end to the telephoto end, an interval between adjacent lens groups varies, and the second lens group G2 is fixed with respect to the image plane MG upon the zooming. The second lens group G2 serves to cut unnecessary light at the intermediate image height or the like.
Upon focusing when the object distance varies from infinity to a short distance, the fourth lens group G4 moves in the optical axis direction to the image plane side.
The first lens group G1 has negative refractive power. The first lens group G1 includes lenses the L11 to L13 in order from the object side toward the image plane side. The lens L11 is a negative meniscus lens with a convex surface opposed to the object side. The lens L12 is a negative meniscus lens with a convex surface opposed to the object side. The lens L13 is a positive meniscus lens with a convex surface opposed to the object side. It is to be noted that a resin layer constituting an aspherical surface (the third surface) is stacked on a surface of the lens L11 on the image plane side.
The second lens group G2 has positive refractive power. The second lens group G2 includes a lens L21. The lens L21 is a positive meniscus lens with a convex surface opposed to the object side.
The third lens group G3 has positive refractive power. The third lens group G3 includes, in order from the object side toward the image plane side, the lens L31, the lens L32, the aperture stop St. and the lenses L33 to L35. The lens L31 is a biconvex lens of an aspherical shape. The lens L32 is a negative lens of a biconcave shape. The lens L33 is a negative meniscus lens with a convex surface opposed to the object side. The lens L34 is a positive lens of a biconvex shape. The lens L33 and the lens L34 constitute a cemented lens in which the lens L33 and the lens L34 are attached to each other. The lens L35 is a biconvex lens of an aspherical shape.
The fourth lens group G4 has negative refractive power. The fourth lens group G4 includes the lens L41 and the lens L42 in order from the object side toward the image plane side. The lens L41 is a positive meniscus lens with a convex surface opposed to the image plane side. The lens L42 is a negative lens of a biconcave shape. The lens L41 and the lens L42 constitute a cemented lens in which the lens L41 and the lens L42 are attached to each other.
The fifth lens group G5 has positive refractive power. The fifth lens group G5 includes the lens L51 and the lens L52 in order from the object side toward the image plane side. The lens L51 is a positive lens of a biconvex shape. The lens L52 is a negative lens of an aspherical shape on both sides.
The above-described configuration allows for achievement of miniaturization and a light weight despite a wide angle as well as achievement of a zoom lens with less variation in an angle of view and with less variation in aberration.
As appreciated from each of the aberration diagrams, the zoom lens 5 according to Example 5 undergoes favorable correction of various aberrations, and thus has superior image-forming performance.
Table 26 summarizes values related to the above-described respective conditional expressions or the like for each of the Examples. As appreciated from Table 26, the values of each of the Examples fall within the respective numerical ranges for the conditional expressions.
A technology according to the present disclosure is applicable to various products. For example, the technology according to the present disclosure may be implemented as an apparatus to be mounted on a movable body of any kind of an automobile, an electric vehicle, a hybrid electric automobile, a motorcycle, a bicycle, a personal mobility, an airplane, a drone, a vessel, a robot, a construction machine, an agricultural machine (a tractor), and the like.
Each of the control units includes: a microcomputer that performs arithmetic processing according to various kinds of programs; a storage section that stores the programs executed by the microcomputer, parameters used for various kinds of operations, or the like; and a driving circuit that drives various kinds of control target devices. Each of the control units further includes: a network interface (I/F) for performing communication with other control units via the communication network 7010; and a communication I/F for performing communication with a device, a sensor, or the like within and without the vehicle by wire communication or radio communication. A functional configuration of the integrated control unit 7600 illustrated in
The driving system control unit 7100 controls the operation of devices related to the driving system of the vehicle in accordance with various kinds of programs. For example, the driving system control unit 7100 functions as a control device for a driving force generating device for generating the driving force of the vehicle, such as an internal combustion engine, a driving motor, or the like, a driving force transmitting mechanism for transmitting the driving force to wheels, a steering mechanism for adjusting the steering angle of the vehicle, a braking device for generating the braking force of the vehicle, and the like. The driving system control unit 7100 may have a function as a control device of an antilock brake system (ABS), electronic stability control (ESC), or the like.
The driving system control unit 7100 is connected with a vehicle state detecting section 7110. The vehicle state detecting section 7110, for example, includes at least one of a gyro sensor that detects the angular velocity of axial rotational movement of a vehicle body, an acceleration sensor that detects the acceleration of the vehicle, and sensors for detecting an amount of operation of an accelerator pedal, an amount of operation of a brake pedal, the steering angle of a steering wheel, an engine speed or the rotational speed of wheels, and the like. The driving system control unit 7100 performs arithmetic processing using a signal input from the vehicle state detecting section 7110, and controls the internal combustion engine, the driving motor, an electric power steering device, the brake device, and the like.
The body system control unit 7200 controls the operation of various kinds of devices provided to the vehicle body in accordance with various kinds of programs. For example, the body system control unit 7200 functions as a control device for a keyless entry system, a smart key system, a power window device, or various kinds of lamps such as a headlamp, a backup lamp, a brake lamp, a turn signal, a fog lamp, or the like. In this case, radio waves transmitted from a mobile device as an alternative to a key or signals of various kinds of switches can be input to the body system control unit 7200. The body system control unit 7200 receives these input radio waves or signals, and controls a door lock device, the power window device, the lamps, or the like of the vehicle.
The battery control unit 7300 controls a secondary battery 7310, which is a power supply source for the driving motor, in accordance with various kinds of programs. For example, the battery control unit 7300 is supplied with information about a battery temperature, a battery output voltage, an amount of charge remaining in the battery, or the like from a battery device including the secondary battery 7310. The battery control unit 7300 performs arithmetic processing using these signals, and performs control for regulating the temperature of the secondary battery 7310 or controls a cooling device provided to the battery device or the like.
The outside-vehicle information detecting unit 7400 detects information about the outside of the vehicle including the vehicle control system 7000. For example, the outside-vehicle information detecting unit 7400 is connected with at least one of an imaging section 7410 and an outside-vehicle information detecting section 7420. The imaging section 7410 includes at least one of a time-of-flight (ToF) camera, a stereo camera, a monocular camera, an infrared camera, and other cameras. The outside-vehicle information detecting section 7420, for example, includes at least one of an environmental sensor for detecting current atmospheric conditions or weather conditions and a peripheral information detecting sensor for detecting another vehicle, an obstacle, a pedestrian, or the like on the periphery of the vehicle including the vehicle control system 7000.
The environmental sensor, for example, may be at least one of a rain drop sensor detecting rain, a fog sensor detecting a fog, a sunshine sensor detecting a degree of sunshine, and a snow sensor detecting a snowfall. The peripheral information detecting sensor may be at least one of an ultrasonic sensor, a radar device, and a LIDAR device (Light detection and Ranging device, or Laser imaging detection and ranging device). Each of the imaging section 7410 and the outside-vehicle information detecting section 7420 may be provided as an independent sensor or device, or may be provided as a device in which a plurality of sensors or devices are integrated.
Incidentally,
Outside-vehicle information detecting sections 7920, 7922, 7924, 7926, 7928, and 7930 provided to the front, rear, sides, and corners of the vehicle 7900 and the upper portion of the windshield within the interior of the vehicle may be, for example, an ultrasonic sensor or a radar device. The outside-vehicle information detecting sections 7920, 7926, and 7930 provided to the front nose of the vehicle 7900, the rear bumper, the back door of the vehicle 7900, and the upper portion of the windshield within the interior of the vehicle may be a LIDAR device, for example. These outside-vehicle information detecting sections 7920 to 7930 are used mainly to detect a preceding vehicle, a pedestrian, an obstacle, or the like.
Returning to
In addition, on the basis of the received image data, the outside-vehicle information detecting unit 7400 may perform image recognition processing of recognizing a human, a vehicle, an obstacle, a sign, a character on a road surface, or the like, or processing of detecting a distance thereto. The outside-vehicle information detecting unit 7400 may subject the received image data to processing such as distortion correction, alignment, or the like, and combine the image data imaged by a plurality of different imaging sections 7410 to generate a bird's-eye image or a panoramic image. The outside-vehicle information detecting unit 7400 may perform viewpoint conversion processing using the image data imaged by the imaging section 7410 including the different imaging parts.
The in-vehicle information detecting unit 7500 detects information about the inside of the vehicle. The in-vehicle information detecting unit 7500 is, for example, connected with a driver state detecting section 7510 that detects the state of a driver. The driver state detecting section 7510 may include a camera that images the driver, a biosensor that detects biological information of the driver, a microphone that collects sound within the interior of the vehicle, or the like. The biosensor is, for example, disposed in a seat surface, the steering wheel, or the like, and detects biological information of an occupant sitting in a seat or the driver holding the steering wheel. On the basis of detection information input from the driver state detecting section 7510, the in-vehicle information detecting unit 7500 may calculate a degree of fatigue of the driver or a degree of concentration of the driver, or may determine whether the driver is dozing. The in-vehicle information detecting unit 7500 may subject an audio signal obtained by the collection of the sound to processing such as noise canceling processing or the like.
The integrated control unit 7600 controls general operation within the vehicle control system 7000 in accordance with various kinds of programs. The integrated control unit 7600 is connected with an input section 7800. The input section 7800 is implemented by a device capable of input operation by an occupant, such, for example, as a touch panel, a button, a microphone, a switch, a lever, or the like. The integrated control unit 7600 may be supplied with data obtained by voice recognition of voice input through the microphone. The input section 7800 may, for example, be a remote control device using infrared rays or other radio waves, or an external connecting device such as a mobile telephone, a personal digital assistant (PDA), or the like that supports operation of the vehicle control system 7000. The input section 7800 may be, for example, a camera. In that case, an occupant can input information by gesture. Alternatively, data may be input which is obtained by detecting the movement of a wearable device that an occupant wears. Further, the input section 7800 may, for example, include an input control circuit or the like that generates an input signal on the basis of information input by an occupant or the like using the above-described input section 7800, and which outputs the generated input signal to the integrated control unit 7600. An occupant or the like inputs various kinds of data or gives an instruction for processing operation to the vehicle control system 7000 by operating the input section 7800.
The storage section 7690 may include a read only memory (ROM) that stores various kinds of programs executed by the microcomputer and a random access memory (RAM) that stores various kinds of parameters, operation results, sensor values, or the like. In addition, the storage section 7690 may be implemented by a magnetic storage device such as a hard disc drive (HDD) or the like, a semiconductor storage device, an optical storage device, a magneto-optical storage device, or the like.
The general-purpose communication I/F 7620 is a communication IF used widely, which communication I/F mediates communication with various apparatuses present in an external environment 7750. The general-purpose communication I/F 7620 may implement a cellular communication protocol such as global system for mobile communications (GSM (registered trademark)), worldwide interoperability for microwave access (WiMAX (registered trademark)), long term evolution (LTE (registered trademark)), LTE-advanced (LTE-A), or the like, or another wireless communication protocol such as wireless LAN (referred to also as wireless fidelity (Wi-Fi (registered trademark)), Bluetooth (registered trademark), or the like. The general-purpose communication I/F 7620 may, for example, connect to an apparatus (for example, an application server or a control server) present on an external network (for example, the Internet, a cloud network, or a company-specific network) via a base station or an access point. In addition, the general-purpose communication I/F 7620 may connect to a terminal present in the vicinity of the vehicle (which terminal is, for example, a terminal of the driver, a pedestrian, or a store, or a machine type communication (MTC) terminal) using a peer to peer (P2P) technology, for example.
The dedicated communication I/F 7630 is a communication IF that supports a communication protocol developed for use in vehicles. The dedicated communication I/F 7630 may implement a standard protocol such, for example, as wireless access in vehicle environment (WAVE), which is a combination of institute of electrical and electronic engineers (IEEE) 802.11p as a lower layer and IEEE 1609 as a higher layer, dedicated short range communications (DSRC), or a cellular communication protocol. The dedicated communication IF 7630 typically carries out V2X communication as a concept including one or more of communication between a vehicle and a vehicle (Vehicle to Vehicle), communication between a road and a vehicle (Vehicle to Infrastructure), communication between a vehicle and a home (Vehicle to Home), and communication between a pedestrian and a vehicle (Vehicle to Pedestrian).
The positioning section 7640, for example, performs positioning by receiving a global navigation satellite system (GNSS) signal from a GNSS satellite (for example, a GPS signal from a global positioning system (GPS) satellite), and generates positional information including the latitude, longitude, and altitude of the vehicle. Incidentally, the positioning section 7640 may identify a current position by exchanging signals with a wireless access point, or may obtain the positional information from a terminal such as a mobile telephone, a personal handyphone system (PHS), or a smart phone that has a positioning function.
The beacon receiving section 7650, for example, receives a radio wave or an electromagnetic wave transmitted from a radio station installed on a road or the like, and thereby obtains information about the current position, congestion, a closed road, a necessary time, or the like. Incidentally, the function of the beacon receiving section 7650 may be included in the dedicated communication I/F 7630 described above.
The in-vehicle device I/F 7660 is a communication interface that mediates connection between the microcomputer 7610 and various in-vehicle devices 7760 present within the vehicle. The in-vehicle device I/F 7660 may establish wireless connection using a wireless communication protocol such as wireless LAN, Bluetooth (registered trademark), near field communication (NFC), or wireless universal serial bus (WUSB). In addition, the in-vehicle device I/F 7660 may establish wired connection by universal serial bus (USB), high-definition multimedia interface (HDMI (registered trademark)), mobile high-definition link (MHL), or the like via a connection terminal (and a cable if necessary) not depicted in the figures. The in-vehicle devices 7760 may, for example, include at least one of a mobile device and a wearable device possessed by an occupant and an information device carried into or attached to the vehicle. The in-vehicle devices 7760 may also include a navigation device that searches for a path to an arbitrary destination. The in-vehicle device IF 7660 exchanges control signals or data signals with these in-vehicle devices 7760.
The vehicle-mounted network I/F 7680 is an interface that mediates communication between the microcomputer 7610 and the communication network 7010. The vehicle-mounted network I/F 7680 transmits and receives signals or the like in conformity with a predetermined protocol supported by the communication network 7010.
The microcomputer 7610 of the integrated control unit 7600 controls the vehicle control system 7000 in accordance with various kinds of programs on the basis of information obtained via at least one of the general-purpose communication IF 7620, the dedicated communication I/F 7630, the positioning section 7640, the beacon receiving section 7650, the in-vehicle device I/F 7660, and the vehicle-mounted network LT 7680. For example, the microcomputer 7610 may calculate a control target value for the driving force generating device, the steering mechanism, or the braking device on the basis of the obtained information about the inside and outside of the vehicle, and output a control command to the driving system control unit 7100. For example, the microcomputer 7610 may perform cooperative control intended to implement functions of an advanced driver assistance system (ADAS) which functions include collision avoidance or shock mitigation for the vehicle, following driving based on a following distance, vehicle speed maintaining driving, a warning of collision of the vehicle, a warning of deviation of the vehicle from a lane, or the like. In addition, the microcomputer 7610 may perform cooperative control intended for automated driving, which makes the vehicle to travel automatedly without depending on the operation of the driver, or the like, by controlling the driving force generating device, the steering mechanism, the braking device, or the like on the basis of the obtained information about the surroundings of the vehicle.
The microcomputer 7610 may generate three-dimensional distance information between the vehicle and an object such as a surrounding structure, a person, or the like, and generate local map information including information about the surroundings of the current position of the vehicle, on the basis of information obtained via at least one of the general-purpose communication I/F 7620, the dedicated communication I/F 7630, the positioning section 7640, the beacon receiving section 7650, the in-vehicle device I/F 7660, and the vehicle-mounted network I/F 7680. In addition, the microcomputer 7610 may predict danger such as collision of the vehicle, approaching of a pedestrian or the like, an entry to a closed road, or the like on the basis of the obtained information, and generate a warning signal. The warning signal may, for example, be a signal for producing a warning sound or lighting a warning lamp.
The sound/image output section 7670 transmits an output signal of at least one of a sound and an image to an output device capable of visually or auditorily notifying information to an occupant of the vehicle or the outside of the vehicle. In the example of
Incidentally, at least two control units connected to each other via the communication network 7010 in the example depicted in
In the vehicle control system 7000 described above, the zoom lens and the imaging apparatus of the present disclosure are applicable to any of the imaging section 7410 and the imaging sections 7910, 7912, 7914, 7916, and 7918.
A technology according to the present disclosure is applicable to a medical imaging system. The medical imaging system is a medical system using an imaging technology, and is, for example, an endoscope system or a microscope system.
An example of the endoscope system will be described using
In endoscopic surgery, insertion assisting tools called trocars 5025 are punctured into the patient 5071. Then, a scope 5003 connected to the endoscope 5001 and surgical tools 5021 are inserted into a body of the patient 5071 through the trocars 5025. The surgical tools 5021 include: an energy device such as an electric scalpel; and forceps, for example.
A surgical image that is a medical image in which the inside of the body of the patient 5071 is captured by the endoscope 5001 is displayed on a display device 5041. The operator 5067 performs a procedure on a surgical target using the surgical tools 5021 while viewing the surgical image displayed on the display device 5041. The medical image is not limited to the surgical image, and may be a diagnostic image captured during diagnosis.
The endoscope 5001 is an imaging section for capturing the inside of the body of the patient 5071, and is, for example, as illustrated in
The CCU 5039 is a control device for controlling the endoscope 5001 and the light source device 5043 connected to the CCU 5039 in an integrated manner, and is, for example, as illustrated in
The CCU 5039 may be connected to external equipment (such as a recording device, a display device, an output device, and a support device) via an IP converter for converting the signal into a predetermined communication protocol (such as the Internet Protocol (IP)). The connection between the IP converter and the external equipment may be established using a wired network, or a part or the whole of the network may be established using a wireless network. For example, the IP converter on the CCU 5039 side may have a wireless communication function, and may transmit the received image to an IP switcher or an output side IP converter via a wireless communication network, such as the fifth-generation mobile communication system (5G) or the sixth-generation mobile communication system (6G).
The light source device 5043 is a device capable of emitting the light having predetermined wavelength bands, and includes, for example, a plurality of light sources and a light source optical system for guiding the light of the light sources. The light sources are, for example, xenon lamps, light-emitting diode (LED) light sources, or laser diode (LD) light sources. The light source device 5043 includes, for example, the LED light sources corresponding to three respective primary colors of red (R), green (G), and blue (B), and controls output intensity and output timing of each of the light sources to emit white light. The light source device 5043 may include a light source capable of emitting special light used for special light observation, in addition to the light sources for emitting normal light for normal light observation. The special light is light having a predetermined wavelength band different from that of the normal light being light for the normal light observation, and is, for example, near-infrared light (light having a wavelength of 760 nm or longer), infrared light, blue light, or ultraviolet light. The normal light is, for example, the white light or green light. In narrow band imaging that is a kind of special light observation, blue light and green light are alternately emitted, and thus the narrow band imaging can image a predetermined tissue such as a blood vessel in a mucosal surface at high contrast using wavelength dependence of light absorption in the tissue of the body. In fluorescence observation that is a kind of special light observation, excitation light is emitted for exciting an agent injected into the tissue of the body, and fluorescence emitted by the tissue of the body or the agent as a label is received to obtain a fluorescent image, and thus the fluorescence observation can facilitate the operator to view, for example, the tissue of the body that is difficult to be viewed by the operator with the normal light. For example, in fluorescence observation using the infrared light, the infrared light having an excitation wavelength band is emitted to an agent, such as indocyanine green (ICG), injected into the tissue of the body, and the fluorescence light from the agent is received, whereby the fluorescence observation can facilitate viewing of a structure and an affected part of the tissue of the body. In the fluorescence observation, an agent (such as 5-aminolevulinic acid (5-ALA)) may be used that emits fluorescence in a red wavelength band by being excited by the special light in a blue wavelength band. The type of the irradiation light of the light source device 5043 is set by control of the CCU 5039. The CCU 5039 may have a mode of controlling the light source device 5043 and the endoscope 5001 to alternately perform the normal light observation and the special light observation. At this time, information based on a pixel signal obtained by the special light observation is preferably superimposed on a pixel signal obtained by the normal light observation. The special light observation may be an infrared light observation to observe a site inside the surface of an organ and a multi-spectrum observation utilizing hyperspectral spectroscopy. A photodynamic therapy may be incorporated.
The recording device 5053 is a device for recording the pixel signal (for example, an image) acquired from the CCU 5039, and is, for example, a recorder. The recording device 5053 records an image acquired from the CCU 5039 in a hard disk drive (HDD), a Super Density Disc (SDD), and/or an optical disc. The recording device 5053 may be connected to a network in a hospital to be accessible from equipment outside the operating room. The recording device 5053 may have a down-convert function or an up-convert function.
The display device 5041 is a device capable of displaying the image, and is, for example, a display monitor. The display device 5041 displays a display image based on the pixel signal acquired from the CCU 5039. The display device 5041 may include a camera and a microphone to function as an input device that allows instruction input through gaze recognition, voice recognition, and gesture.
The output device 5055 is a device for outputting the information acquired from the CCU 5039, and is, for example, a printer. The output device 5055 prints, for example, a print image based on the pixel signal acquired from the CCU 5039 on a sheet of paper.
The support device 5027 is an articulated arm including a base 5029 including an arm control device 5045, an arm 5031 extending from the base 5029, and a holding part 5032 mounted at a distal end of the arm 5031. The arm control device 5045 includes a processor such as a CPU, and operates according to a predetermined computer program to control driving of the arm 5031. The support device 5027 uses the arm control device 5045 to control parameters including, for example, lengths of links 5035 constituting the arm 5031 and rotation angles and torque of joints 5033 so as to control, for example, the position and attitude of the endoscope 5001 held by the holding part 5032. This control can change the position or attitude of the endoscope 5001 to a desired position or attitude, makes it possible to insert the scope 5003 into the patient 5071, and can change the observed area in the body. The support device 5027 functions as an endoscope support arm for supporting the endoscope 5001 during the operation. This, the support device 5027 can play a role of a scopist who is an assistant holding the endoscope 5001. The support device 5027 may be a device for holding a microscope device 5301 to be described later, and can be called a medical support arm. The support device 5027 may be controlled using an autonomous control method by the arm control device 5045, or may be controlled using a control method in which the arm control device 5045 performs the control based on input of a user. The control method may be, for example, a master-slave method in which the support device 5027 serving as a slave device (replica device) that is a patient cart is controlled based on a movement of a master device (primary device) that is an operator console at a hand of the user. The support device 5027 may be remotely controllable from outside the operating room.
The example of the endoscope system 5000 to which the technology according to the present disclosure is applicable has been described above. For example, the technology according to the present disclosure may be applied to a microscope system.
As illustrated in
The respective examples of the endoscope system 5000 and the microscopic surgery system 5300 to which the technology according to the present disclosure is applicable have been described above. Systems to which the technology according to the present disclosure is applicable are not limited to such examples. For example, the support device 5027 can support, at the distal end thereof, another observation device or another surgical tool instead of the endoscope 5001 or the microscope 5303. Examples of the other applicable observation device include forceps, tweezers, a pneumoperitoneum tube for pneumoperitoneum, and an energy treatment tool for incising a tissue or sealing a blood vessel by cauterization. By using the support device to support the observation device or the surgical tool described above, the position thereof can be more stably fixed and the load of the medical staff can be lower than in a case where the medical staff manually supports the observation device or the surgical tool. The technology according to the present disclosure may be applied to a support device for supporting such a component other than the microscope.
The technology according to the present disclosure is suitably applicable to the camera 5005 among the configurations described above. In particular, the zoom lens of the present disclosure is suitably applicable to at least some of the optical systems of the condensing optical system 50051, the zooming optical system 50052, and the focusing optical system 50053 in the camera 5005.
The technology according to the present disclosure is not limited to the descriptions of an embodiment and examples described above, and may be modified and worked in a wide variety of ways.
For example, shapes and numerical values of the respective parts exemplified in the foregoing embodiment and examples are each a mere example of implementation of the present technology, and the technical scope of the present technology should not be construed as being limited by these examples.
In addition, for examples, a configuration may be employed that includes different number of lenses from the number of lenses exhibited in the foregoing embodiment and examples. Further, a configuration may be employed that further includes a lens having no substantial refractive power.
For example, the present technology may also have the following configurations.
According to the present technology of the following configuration, the configurations of the respective lens groups are optimized to enable high optical performance in the entire zoom range and achievement in miniaturization and a wider angle of view. This makes it possible to provide a zoom lens that has high optical performance in the entire zoom range and that enables achievement in miniaturization and a wider angle of view, and an imaging apparatus including such a zoom lens.
A zoom lens including, in order from a side of an object toward a side of an image plane:
The zoom lens according to [1], further including a fifth lens group disposed on a side closer to the image plane than the fourth lens group, the fifth lens group having positive refractive power.
[3]
The zoom lens according to [1] or [2], in which the fourth lens group moves in an optical axis direction upon focusing.
[4]
The zoom lens according to any one of [1] to [3], in which the following conditional expression is further satisfied:
The zoom lens according to any one of [1] to [4], in which the following conditional expression is further satisfied:
The zoom lens according to any one of [1] to [5], in which the following conditional expression is further satisfied:
The zoom lens according to any one of [1] to [6], further including an aperture stop disposed on a side closer to the image plane than the second lens group.
[8]
An imaging apparatus including:
The zoom lens according to any one of [1] to [7], further including a lens having no substantial refractive power.
[10]
The imaging apparatus according to [8], in which the zoom lens further includes a lens having no substantial refractive power.
The present application claims the benefit of Japanese Priority Patent Application JP2022-46576 filed with the Japan Patent Office on Mar. 23, 2022, the entire contents of which are incorporated herein by reference.
It should be understood by those skilled in the art that various modifications, combinations, sub-combinations, and alterations may occur depending on design requirements and other factors insofar as they are within the scope of the appended claims or the equivalents thereof.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2022-046576 | Mar 2022 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2023/003795 | 2/6/2023 | WO |
