Zoom lens and imaging apparatus having the same

Abstract

To provide a zoom lens that has high optical performance, a long focal length, and a small size and light weight.SOLUTION: A zoom lens consists of a first lens group having a positive refractive power, a second lens group, a third lens group having a negative refractive power, and a rear group having one or more lens groups, which are arranged in order from an object side to an image side, and in zooming, the interval between the adjacent lens groups changes. The first lens group has a first positive lens having a positive refractive power arranged on the most object side. The rear group has a positive refractive power at a wide angle end. Predetermined conditional expressions are satisfied.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a zoom lens, which is suitable for use in imaging devices such as digital video cameras, digital still cameras, broadcast cameras, and cameras for silver halide film. [Background technology]

[0002] In recent years, imaging optical systems used in imaging devices are required to have small, lightweight zoom lenses that have high optical performance over the entire zoom range while having a long focal length at the telephoto end.

[0003] As a zoom lens having a long focal length at the telephoto end, Patent Document 1 discloses a positive lead type optical system. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2018-116182 A Summary of the Invention [Problem to be solved by the invention]

[0005] The zoom lens of Patent Document 1 has a first lens group with positive refractive power and a second lens group with negative refractive power arranged in that order from the object side to the image side, and the first lens group does not move during zooming. However, because the refractive power of the first lens group is weak, the principal point of the entire system is located on the image side, which makes the overall lens length long.

[0006] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a zoom lens that has high optical performance, a long focal length, and is small and lightweight. [Means for solving the problem]

[0007] A zoom lens of the present invention comprises, in order from the object side to the image side, a first lens group having positive refractive power, a second lens group, a third lens group having negative refractive power, and a rear group having one or more lens groups, and the distance between adjacent lens groups changes during zooming, the first lens group includes a first positive lens having a positive refractive power, which does not move during zooming and is disposed closest to the object side; the rear group has positive refractive power at a wide-angle end, Let f1 be the focal length of the first lens group, f2 be the focal length of the second lens group, Lt be the total lens length at the telephoto end, and ft be the focal length of the entire system at the telephoto end. 0.05 <f1 / |f2|<2.00 0.40 <Lt / ft<0.65 The present invention is characterized in that the following conditional expression is satisfied: Effect of the Invention

[0008] According to the present invention, it is possible to provide a zoom lens that has high optical performance, a long focal length, and is small and lightweight. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a cross-sectional view of a zoom lens at a wide-angle end according to a first embodiment. [Diagram 2] Aberration diagrams of the zoom lens of Example 1 at (A) the wide-angle end and (B) the telephoto end when focusing at infinity. [Diagram 3] Aberration diagrams of the zoom lens of Example 1 at (A) the wide-angle end and (B) the telephoto end when focusing at close range. [Figure 4] 1 is a cross-sectional view of a zoom lens at a wide-angle end according to a second embodiment of the present invention; [Diagram 5] Aberration diagrams of the zoom lens of Example 2 at (A) the wide-angle end and (B) the telephoto end when focusing at infinity. [Figure 6] Aberration diagrams of the zoom lens of Example 2 at (A) the wide-angle end and (B) the telephoto end when focusing at close range. [Figure 7] 11 is a cross-sectional view of a zoom lens at a wide-angle end according to a third embodiment of the present invention; [Figure 8] Aberration diagrams of the zoom lens of Example 3 at (A) the wide-angle end and (B) the telephoto end when focusing at infinity. [Figure 9] Aberration diagrams of the zoom lens of Example 3 at (A) the wide-angle end and (B) the telephoto end when focusing at close range. [Figure 10] 11 is a cross-sectional view of a zoom lens at a wide-angle end according to a fourth embodiment of the present invention; [Figure 11] Aberration diagrams of the zoom lens of Example 4 at (A) the wide-angle end and (B) the telephoto end when focusing at infinity. [Figure 12] Aberration diagrams of the zoom lens of Example 4 at (A) the wide-angle end and (B) the telephoto end when focusing at close range. [Figure 13] 13 is a cross-sectional view of a zoom lens at a wide-angle end according to a fifth embodiment of the present invention; [Figure 14] Aberration diagrams of the zoom lens of Example 5 at (A) the wide-angle end and (B) the telephoto end when focusing at infinity. [Figure 15] Aberration diagrams of the zoom lens of Example 5 at (A) the wide-angle end and (B) the telephoto end when focusing at close range. [Figure 16] 13 is a cross-sectional view of a zoom lens at a wide-angle end according to a sixth embodiment of the present invention; [Figure 17] Aberration diagrams of the zoom lens of Example 6 at (A) the wide-angle end and (B) the telephoto end when focusing at infinity. [Figure 18] Aberration diagrams of the zoom lens of Example 6 at (A) the wide-angle end and (B) the telephoto end when focusing at close range. [Figure 19] 13 is a cross-sectional view of a zoom lens according to a seventh embodiment at the wide-angle end. [Figure 20] Aberration diagrams of the zoom lens of Example 7 at (A) the wide-angle end and (B) the telephoto end when focusing at infinity. [Figure 21]Aberration diagrams of the zoom lens of Example 7 at (A) the wide-angle end and (B) the telephoto end when focusing at close range. [Figure 22] 13 is a cross-sectional view of a zoom lens according to an eighth embodiment at the wide-angle end. [Diagram 23] Aberration diagrams of the zoom lens of Example 8 at (A) the wide-angle end and (B) the telephoto end when focusing at infinity. [Figure 24] Aberration diagrams of the zoom lens of Example 8 at (A) the wide-angle end and (B) the telephoto end when focusing at close range. [Diagram 25] Schematic diagram showing an imaging device DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a zoom lens and an image pickup apparatus having the same according to the present invention will be described with reference to the accompanying drawings.

[0011] 1, 4, 7, 10, 13, 16, 19, and 22 are cross-sectional views at the wide-angle end of the zoom lens L0 of Examples 1 to 8. The zoom lens L0 of each Example is a zoom lens used in imaging devices such as digital video cameras, digital still cameras, broadcast cameras, silver halide film cameras, surveillance cameras, and vehicle-mounted cameras.

[0012] In each lens cross-sectional view, the left side is the object side and the right side is the image side. The zoom lens L0 of each embodiment may be used as a projection lens for a projector, etc. In this case, the left side is the screen side and the right side is the projected image side.

[0013] The zoom lens L0 of each embodiment is composed of a first lens group L1 with positive refractive power, a second lens group L2, a third lens group L3 with negative refractive power, and a rear group LR having one or more lens groups, arranged in this order from the object side to the image side. The interval between adjacent lens groups changes during zooming. Each lens group may be composed of one lens or multiple lenses. The lens groups may also include an aperture stop.

[0014] The solid arrows pointing downward in each lens cross-sectional view indicate the movement locus of each lens group during zooming from the wide-angle end to the telephoto end, while the solid arrows pointing upward in each lens cross-sectional view indicate the movement direction of the lens group during focusing from infinity to a close distance and the movement direction of the lens group during image blur correction.

[0015] In each lens cross-sectional view, SP is an aperture stop. IP is an image plane, and when the zoom lens L0 of each embodiment is used in a digital still camera or digital video camera, the imaging surface of a solid-state imaging element (photoelectric conversion element) such as a CCD sensor or CMOS sensor is disposed thereon. When the zoom lens L0 of each embodiment is used as the photographing optical system of a silver halide film camera, a photosensitive surface equivalent to the film surface is disposed on the image plane IP.

[0016] FL is an optical block equivalent to an optical filter, a face plate, a crystal low-pass filter, an infrared cut filter, etc.

[0017] 2, 5, 8, 11, 14, 17, 20, and 23 are aberration diagrams of the zoom lenses of Examples 1 to 8, respectively, at the wide-angle end and the telephoto end when focusing at infinity.

[0018] 3, 6, 9, 12, 15, 18, 21, and 24 are aberration diagrams of the zoom lenses of Examples 1 to 8 at the wide-angle end and the telephoto end, respectively, when focusing at close range.

[0019] In the spherical aberration diagram, Fno is the F-number, the solid line shows the amount of spherical aberration for the d-line (wavelength 587.6 nm) and the dashed line shows the amount of spherical aberration for the g-line (wavelength 435.8 nm). In the astigmatism diagram, the solid line shows the amount of aberration on the sagittal image plane, and the dashed line shows the amount of aberration on the meridional image plane. The distortion aberration diagram shows the amount of distortion aberration for the d-line. The chromatic aberration diagram shows the amount of lateral chromatic aberration for the g-line. ω is the half angle of view (°).

[0020] Next, the characteristic configuration of the zoom lens of each embodiment will be described.

[0021] In the zoom lens L0 of each embodiment, the refractive power of the first lens group L1 is made positive, so that the principal point is easily located on the object side, and the overall lens length is shortened. Here, the overall lens length is the sum of the distance on the optical axis from the surface of the zoom lens L0 closest to the object to the surface of the zoom lens L0 closest to the image side, and the back focus. Here, the back focus is the air-equivalent value of the distance on the optical axis between the surface of the zoom lens L0 closest to the image side and the image plane.

[0022] In addition, the second lens group L2 is provided to correct off-axis aberrations, particularly at the wide-angle end. The third lens group L3 has a negative refractive power to correct lateral chromatic aberration, particularly at the wide-angle end. Furthermore, the rear group LR, which has one or more lens groups, is provided to suppress fluctuations in aberrations that occur during zooming.

[0023] Furthermore, by keeping the first lens unit L1 stationary during zooming from the wide-angle end to the telephoto end, decentering of the first lens unit L1 during zooming caused by manufacturing errors and the like is suppressed, and fluctuations in various aberrations due to decentering are reduced.

[0024] The rear group LR has positive refractive power at the wide-angle end. In other words, the composite focal length of all the lens groups arranged in the rear group LR is positive. The rear group LR has positive refractive power at the wide-angle end, which corrects spherical aberration and the like, particularly at the wide-angle end.

[0025] In addition, the first lens group L1 has a first positive lens GP1 with positive refractive power that is arranged closest to the object, thereby converging the axial light beam passing through the first positive lens GP1 and reducing the diameter of each lens arranged closer to the image side than the positive lens GP1.

[0026] Moreover, the zoom lens L0 in each embodiment is configured to satisfy the following conditional expressions. 0.05 <f1 / |f2|<2.00···(1) 0.40 <Lt / ft<0.65···(2)

[0027] Here, f1 is the focal length of the first lens group L1, f2 is the focal length of the second lens group L2, Lt is the total lens length at the telephoto end, and ft is the focal length of the entire system at the telephoto end.

[0028] Conditions (1) and (2) are intended to achieve favorable correction of various aberrations, a long focal length, and compact, lightweight design.

[0029] If the upper limit of conditional expression (1) is exceeded, the refractive power of the first lens group L1 becomes too weak, and the principal point of the entire system is located on the image side. As a result, the overall lens length becomes long, which is undesirable. If the lower limit of conditional expression (1) is exceeded, the refractive power of the first lens group L1 becomes too strong, and it becomes difficult to correct spherical aberration and axial chromatic aberration, especially at the telephoto end.

[0030] If the upper limit of condition (2) is exceeded, the overall lens length at the telephoto end becomes too long, which is undesirable, whereas if the lower limit of condition (2) is not reached, the refractive power of each lens group becomes too strong, making it difficult to correct various aberrations.

[0031] With the above configuration, it is possible to realize a zoom lens that has high optical performance, a long focal length, and is small and lightweight.

[0032] It is preferable that at least one of the upper limit and the lower limit of the numerical range of either condition (1) or (2) satisfies the numerical value of the following condition (1a) or (2a). 0.10 <f1 / |f2|<1.95···(1a) 0.44 <Lt / ft<0.63···(2a)

[0033] It is even more preferable that at least one of the upper limit and the lower limit of the numerical range of either conditional formula (1) or (2) satisfies the range of the following conditional formula (1b) or (2b). 0.15 <f1 / |f2|<1.90···(1b) 0.47 <Lt / ft<0.62···(2b)

[0034] Next, a preferred configuration of the zoom lens L0 in each embodiment will be described.

[0035] The rear group LR preferably has a first focus lens group LRF that moves during focusing from infinity to a close distance. Since the lenses in the rear group LR have a relatively small diameter, the first focus lens group LRF moves during focusing, making it possible to reduce the weight of the lens groups that move during focusing.

[0036] Furthermore, it is preferable that the first focus lens group LRF has negative refractive power and moves toward the image side during focusing from infinity to close range. This makes it possible to increase the position sensitivity of the first focus lens group LRF, i.e., the absolute value of the amount of movement of the image plane position relative to the amount of movement of the first focus lens group LRF. As a result, the amount of movement of the first focus lens group LRF during focusing can be reduced, and the diameter of the first focus lens group LRF can be made smaller.

[0037] Furthermore, it is preferable that the rear group LR has a second focus lens unit LF2, and that the first focus lens unit LRF and the second focus lens unit LF2 move on different trajectories during focusing from infinity to close range, which makes it easier to suppress fluctuations in various aberrations that occur during focusing.

[0038] It is preferable that the first lens group L1 is composed of four or less lenses. Since the diameter of the lens arranged in the first lens group L1 is relatively large, the weight is reduced by being composed of four or less lenses.

[0039] The first lens group L1 is composed of a first subgroup L1A and a second subgroup L1B arranged adjacent to the image side of the first subgroup L1A. Furthermore, among the air gaps on the optical axis between adjacent lenses in the first lens group L1, it is preferable that the air gap on the optical axis between the first subgroup L1A and the second subgroup L1B is the largest, and the first subgroup L1A is composed of two or less lenses. Since the diameter of the lens arranged on the object side in the first lens group L1 is relatively large, the weight can be reduced by configuring the first subgroup L1A with two or less lenses.

[0040] It is preferable that the zoom lens L0 of each embodiment satisfies one or more of the following conditional expressions. 0.02 <d1AB / f1A<0.35···(3) 1.1<βLRF1<4.0 (4) -10.0<(1-βLRF1×βLRF1)×βR1×βR1<-3.0 (5) 0.09 <sk / Lt<0.3···(6) 1.2 <f1 / fLP<6.0···(7) -5.0 <f1 / f3<-0.5···(8) 0.0<(r2+r1) / (r2-r1)<1.5...(9) 0.1 <f1 / ft<0.8···(10) -3.5<(r2LRF+r1LRF) / (r2LRF-r1LRF)<-0.2...(11) -0.01<θgF_N-(-0.0016178×νd_N+0.64146)<0.01...(12) -0.012<θgF_PR-(-0.0016178×νd_PR+0.64146)<0.005...(13) 0.4 <fLF1 / fLF2<3.0···(14) 0.2 <MLF1 / MLF2<5.0···(15) 0.01 <T×|(1-βLRF2×βLRF2)×βR2×βR2| / f<0.50···(16) 50<νd_RF1N<100 (17) -1000.0<|f2| / f3<-0.3···(18) -1.00 <fLRF / f1<-0.05···(19)

[0041] Here, d1AB is the distance on the optical axis between the surface of the first subgroup L1A closest to the image and the surface of the second subgroup L1B closest to the object, and f1A is the focal length of the first subgroup L1A.

[0042] βLRF1 is the lateral magnification of the first focus lens group LRF when focusing at an object distance where the lateral magnification of the entire system is −0.2 at the telephoto end. βR1 is the combined lateral magnification of all lens groups arranged on the image side of the first focus lens group LRF at the telephoto end.

[0043] sk is the smaller of the back focuses at the wide-angle end and the telephoto end. When the back focuses at the wide-angle end and the telephoto end have the same value, either the back focus at the wide-angle end or the telephoto end is set to sk.

[0044] fLP is the focal length of the lens group with positive refractive power arranged in the rear group LR that is located closest to the object side. f3 is the focal length of the third lens group L3. r1 is the radius of curvature of the object side surface of the first positive lens GP1, and r2 is the radius of curvature of the image side surface of the first positive lens GP1.

[0045] r1LRF is the radius of curvature of the surface of the first focus lens group LRF closest to the object side, and r2LRF is the radius of curvature of the surface of the first focus lens group LRF closest to the image side.

[0046] νd_N and θgF_N are the Abbe number and the partial dispersion ratios for the g-line and F-line, respectively, of the negative lens GN1 arranged closest to the object among the negative lenses arranged in the first lens unit L1.

[0047] The rear group LR has an aperture stop SP that determines an axial light beam, and νd_PR and θgF_PR are the Abbe number and the partial dispersion ratios for the g-line and F-line, respectively, of at least two positive lenses arranged on the image side of the aperture stop SP.

[0048] The zoom lens L0 has a second focus lens group LF2, and of the first focus lens group LRF and the second focus lens group LF2, the lens group arranged on the object side is called the object side focus lens group, and the lens group arranged on the image side is called the image side focus lens group. In this case, fLF1 is the focal length of the object side focus lens group, and fLF2 is the focal length of the image side focus lens group.

[0049] MLF1 and MLF2 are the absolute values ​​of the movement amounts of the object-side focus lens unit and the image-side focus lens unit, respectively, when focusing at the telephoto end from infinity to an object distance where the lateral magnification of the entire system is −0.2.

[0050] T is the distance on the optical axis between the surface closest to the image side of the first focus lens group LRF and the object side surface of the lens located adjacent to the image side of the first focus lens group LRF when focusing at an object distance where the lateral magnification of the entire system is -0.3 at the telephoto end.

[0051] βLRF2 and βR2 are, respectively, the lateral magnification of the first focus lens group LRF when focusing at an object distance where the lateral magnification of the entire system is −0.3, and the composite lateral magnification of all lens groups arranged on the image side of the first focus lens group LRF.

[0052] The first focus lens group LRF has a cemented lens made up of a positive lens and a negative lens, where νd_RF1N is the Abbe number of the negative lens, and fLRF is the focal length of the first focus lens group LRF.

[0053] Next, the technical meanings of the above-mentioned conditional expressions (3) to (19) will be explained.

[0054] If the upper limit of conditional expression (3) is exceeded, the distance on the optical axis between the first sub-group L1A and the second sub-group L1B becomes too long, and the overall lens length becomes long. If the lower limit of conditional expression (3) is not reached, the height from the optical axis of the on-axis light beam incident on the second sub-group L1B becomes too high, and the diameter of the second sub-group L1B becomes large. As a result, it becomes difficult to reduce the weight.

[0055] If the upper limit of conditional expression (4) is exceeded, the refractive power of the first focus lens group LRF becomes too strong, making it difficult to suppress variations in spherical aberration and field curvature during focusing.If the lower limit of conditional expression (4) is not reached, the amount of movement of the first focus lens group LRF that occurs during focusing becomes too large, making the overall lens length long.

[0056] Conditional expression (5) expresses the position sensitivity of the first focus lens group LRF when focusing at an object distance where the lateral magnification of the entire system is -0.2. If the upper limit of conditional expression (5) is exceeded, the amount of movement of the first focus lens group LRF during focusing becomes too large, and the overall lens length becomes long. If the lower limit of conditional expression (5) is exceeded, the refractive power of the first focus lens group LRF becomes too strong, and it becomes difficult to suppress fluctuations in spherical aberration and field curvature that occur during focusing.

[0057] If the upper limit of conditional expression (6) is exceeded, the back focus at the wide-angle end and the telephoto end becomes too long, and the overall lens length at the wide-angle end and the telephoto end becomes long. If the lower limit of conditional expression (6) is not satisfied, the back focus at the wide-angle end or the telephoto end becomes too short. As a result, when an image sensor is placed, ghost light that is generated by reflection between the image sensor and the image-side surface of the lens placed closest to the image side is likely to be imaged by the image sensor, which is undesirable.

[0058] If the upper limit of conditional expression (7) is exceeded, the refractive power of the lens group arranged closest to the object among the lens groups with positive refractive power arranged in the rear group LR becomes too strong, making it difficult to correct spherical aberration, particularly at the wide-angle end.If the lower limit of conditional expression (7) is not reached, the refractive power of the lens group arranged closest to the object among the lens groups with positive refractive power arranged in the rear group LR becomes too weak, and the diameter of the lens group arranged closest to the image becomes large.

[0059] If the upper limit of conditional expression (8) is exceeded, the refractive power of the third lens group L3 becomes too weak. As a result, in order to obtain a desired magnification ratio, the movement amount of the third lens group L3 during zooming becomes too large, and the overall lens length becomes long. If the lower limit of conditional expression (8) is not reached, the refractive power of the third lens group L3 becomes too strong, making it difficult to suppress fluctuations in spherical aberration, axial chromatic aberration, and the like that occur during zooming.

[0060] Conditional formula (9) specifies the shape factor of the first positive lens GP1. If the absolute value of the radius of curvature of the object side surface of the first positive lens GP1 becomes small by exceeding the upper limit of conditional formula (9), it becomes difficult to correct spherical aberration, particularly at the telephoto end. If the absolute value of the radius of curvature of the image side surface of the first positive lens GP1 becomes small by falling below the lower limit of conditional formula (9), the principal point of the entire system is disposed relatively closer to the image side, so that the overall lens length becomes long.

[0061] If the upper limit of conditional expression (10) is exceeded, the refractive power of the first lens group L1 becomes too weak, and the principal point of the entire system is located on the image side. As a result, the overall lens length becomes long, which is undesirable. If the lower limit of conditional expression (10) is exceeded, the refractive power of the first lens group L1 becomes too strong, and it becomes difficult to correct spherical aberration and axial chromatic aberration, especially at the telephoto end.

[0062] When the upper limit of conditional expression (11) is exceeded, the absolute value of the curvature of the surface of the first focus lens group LRF closest to the object side and the absolute value of the curvature of the surface closest to the image side are both large, resulting in a biconcave shape. As a result, the variation of spherical aberration, etc., that occurs during focusing becomes large. When the lower limit of conditional expression (11) is not reached, the absolute value of the curvature of the surface closest to the image side becomes too large. As a result, the amount of movement of the first focus lens group LRF during focusing becomes large, resulting in a long overall lens length. As a result, the variation of field curvature, etc., that occurs during focusing becomes large.

[0063] Conditional expression (12) defines the anomalous dispersion of the negative lens GN1, which is the negative lens arranged closest to the object side among the negative lenses arranged in the first lens group L1. If the upper limit of conditional expression (12) is exceeded, it becomes difficult to correct the lateral chromatic aberration at the telephoto end. If the lower limit of conditional expression (12) is not satisfied, it becomes difficult to correct the lateral chromatic aberration at the wide-angle end.

[0064] Conditional formula (13) specifies the anomalous dispersion of at least two positive lenses arranged on the image side of the aperture stop SP. If the upper limit of conditional formula (13) is exceeded, it becomes difficult to correct lateral chromatic aberration at the telephoto end. If the lower limit of conditional formula (13) is not satisfied, it becomes difficult to correct lateral chromatic aberration at the wide-angle end. Furthermore, by using three to five positive lenses that satisfy conditional formula (13), it is possible to further reduce lateral chromatic aberration at the wide-angle end and the telephoto end.

[0065] If the upper limit of conditional expression (14) is exceeded, the refractive power of the image-side focus lens group becomes too strong, making it difficult to suppress fluctuations in various aberrations that occur during focusing. If the lower limit of conditional expression (14) is not reached, the refractive power of the object-side focus lens group becomes too strong, making it difficult to suppress fluctuations in various aberrations that occur during focusing.

[0066] If the upper limit of conditional expression (15) is exceeded, the amount of movement of the object-side focus lens group becomes too large, which is undesirable because the diameter of the object-side focus lens group must be large in order to ensure the amount of peripheral illumination.If the lower limit of conditional expression (15) is exceeded, the amount of movement of the image-side focus lens group becomes too large, which is undesirable because the diameter of the image-side focus lens group must be large in order to ensure the amount of peripheral illumination.

[0067] Conditional formula (16) defines the condition for enabling focusing at an object distance where the lateral magnification of the entire system is −0.3 at the telephoto end. Due to lens manufacturing errors, the actual image plane position may deviate from the designed image plane position. Therefore, it is preferable that the position in the optical axis direction of the first focus lens group LRF can be changed from a predetermined design position in the optical axis direction by adjustment taking into account lens manufacturing errors so as to correct the deviation of the image plane position to a predetermined image plane position.

[0068] Therefore, it is necessary to ensure the distance T on the optical axis in accordance with the position sensitivity of the first focus lens group LRF.

[0069] When the absolute value of the position sensitivity of the first focus lens group LRF is large, the distance T on the optical axis may be small, and when the absolute value of the position sensitivity of the first focus lens group LRF is small, it is preferable to make the distance T on the optical axis large.

[0070] If the upper limit of conditional expression (16) is exceeded, the distance T on the optical axis becomes too large, which is undesirable as it increases the overall lens length. If the lower limit of conditional expression (16) is exceeded, the distance T on the optical axis becomes too small, which makes it difficult to focus at an object distance at which the lateral magnification of the entire system is -0.3. The position sensitivity of the first focus lens group LRF is given by (1-βLRF2×βLRF2)×βR2×βR2.

[0071] When the upper limit of conditional expression (17) is exceeded, the refractive index of the negative lens disposed in the first focus lens group LRF becomes small. As a result, the absolute value of the curvature of the object side or image side surface of the negative lens becomes large, and the fluctuation of the curvature of field that occurs particularly during focusing becomes large. When the lower limit of conditional expression (17) is exceeded, the fluctuation of the chromatic aberration that occurs during focusing becomes large.

[0072] When the upper limit of conditional expression (18) is exceeded and the refractive power of the third lens group L3 becomes weak, the movement amount of the third lens group L3 during zooming becomes too large, and as a result, the overall lens length becomes long. When the lower limit of conditional expression (18) is exceeded and the refractive power of the third lens group L3 becomes strong, the fluctuation of axial chromatic aberration, astigmatism, and the like that occurs during zooming becomes large.

[0073] When the refractive power of the first focus lens group LRF becomes strong by exceeding the upper limit of conditional expression (19), the fluctuation of the field curvature and the like during focusing becomes large. When the refractive power of the first focus lens group LRF becomes weak by falling below the lower limit of conditional expression (19), the movement amount of the first focus lens group LRF during focusing becomes too large. As a result, the overall lens length becomes long.

[0074] It is more preferable to set at least one of the upper and lower limits of the conditional expressions (3) to (19) within the following numerical ranges. 0.025 <d1AB / f1A<0.30···(3a) 1.2<βLRF1<3.7 (4a) -9.5<(1-βLRF1×βLRF1)×βR1×βR1<-3.2 (5a) 0.095 <sk / Lt<0.270···(6a) 1.4 <f1 / fLP<5.5···(7a) -4.5 <f1 / f3<-0.7···(8a) 0.1<(r2+r1) / (r2-r1)<1.3 (9a) 0.14 <f1 / ft<0.70···(10a) -3.0<(r2LRF+r1LRF) / (r2LRF-r1LRF)<-0.4...(11a) -0.008<θgF_N-(-0.0016178×νd_N+0.64146)<0.008...(12a) -0.011<θgF_PR-(-0.0016178×νd_PR+0.64146)<0.004 (13a) 0.45 <fLF1 / fLF2<2.60···(14a) 0.3 <MLF1 / MLF2<4.2···(15a) 0.015 <T×|(1-βLRF2×βLRF2)×βR2×βR2| / f<0.400···(16a) 54<νd_RF1N<96···(17a) -100.0<|f2| / f3<-0.4 (18a) -0.90 <fLRF / f1<-0.08···(19a)

[0075] Moreover, it is more preferable to set at least one of the upper and lower limits of the conditional expressions (3) to (19) to the following numerical ranges. 0.03 <d1AB / f1A<0.25···(3b) 1.4<βLRF1<3.2 (4b) -9.0<(1-βLRF1×βLRF1)×βR1×βR1<-3.5 (5b) 0.10 <sk / Lt<0.25···(6b) 1.6 <f1 / fLP<5.0···(7b) -4.0 <f1 / f3<-0.9···(8b) 0.2<(r2+r1) / (r2-r1)<1.1 (9b) 0.18 <f1 / ft<0.60···(10b) -2.5<(r2LRF+r1LRF) / (r2LRF-r1LRF)<-0.5...(11b) -0.006<θgF_N-(-0.0016178×νd_N+0.64146)<0.006 (12b) -0.010<θgF_PR-(-0.0016178×νd_PR+0.64146)<0.003...(13b) 0.5 <fLF1 / fLF2<2.2···(14b) 0.4 <MLF1 / MLF2<3.5···(15b) 0.02 <T×|(1-βLRF2×βLRF2)×βR2×βR2| / f<0.30···(16b) 57<νd_RF1N<92···(17b) -50.0<|f2| / f3<-0.5 (18b) -0.70 <fLRF / f1<-0.11···(19b)

[0076] Next, the configuration of the zoom lens L0 in each embodiment will be described in detail. From embodiment 2 onwards, differences from embodiment 1 will be mainly described.

[0077] [Example 1] The zoom lens L0 of the first embodiment is composed of a first lens group L1 with positive refractive power, a second lens group L2 with negative refractive power, a third lens group L3 with negative refractive power, and a rear group LR with positive refractive power at the wide-angle end, which are arranged in this order from the object side to the image side. The rear group LR is composed of a fourth lens group L4 with positive refractive power, a fifth lens group L5 with positive refractive power, a sixth lens group L6 with negative refractive power, a seventh lens group L7 with negative refractive power, and an eighth lens group L8 with positive refractive power, which are arranged in this order from the object side to the image side. By appropriately arranging the lens groups with positive refractive power and the lens groups with negative refractive power, various aberrations are well corrected throughout the entire zoom range.

[0078] During focusing, the sixth lens unit L6 and the seventh lens unit L7 move toward the image side along different trajectories, thereby suppressing fluctuations in various aberrations that occur during focusing.

[0079] During image blur correction, the vibration reduction group LVR arranged in the fourth lens group L4 moves so as to include a direction perpendicular to the optical axis. Since the diameter of each lens arranged in the fourth lens group L4 is relatively small, by placing the vibration reduction group LVR in the fourth lens group L4, the diameter of the vibration reduction group LVR can be made small.

[0080] In each embodiment, it is preferable to provide a flare cut aperture FC for blocking light rays. Each numerical embodiment shows an example of providing a flare cut aperture FC.

[0081] It is preferable to have at least one flare cut aperture FC located adjacent to the object side of the first lens group L1, or located between the surface of the first lens group L1 closest to the object side and the surface closest to the image side, thereby making it possible to appropriately block unnecessary marginal rays on the axis at the telephoto end and reduce ghosting.

[0082] It is preferable to have at least one flare cut aperture FC located adjacent to the object side of the second lens unit L2, or located between the surface of the second lens unit L2 closest to the object side and the surface closest to the image side, thereby making it possible to appropriately block unnecessary off-axis marginal rays and chief rays at the wide-angle end and in the intermediate zoom range, thereby reducing coma aberration and ghosting.

[0083] It is preferable to have at least one flare cut aperture FC located adjacent to the object side of the third lens group L3, or located between the surface of the third lens group L3 closest to the object side and the surface closest to the image side, thereby making it possible to appropriately block unnecessary off-axis marginal rays and chief rays at the wide-angle end and in the intermediate zoom range, thereby reducing coma aberration and ghosts.

[0084] It is preferable that the zoom lens L0 has at least one flare cut aperture FC at a position adjacent to the object side of the lens group arranged closest to the image side, or at a position adjacent to the image side of the lens group arranged closest to the image side, which can appropriately block unnecessary off-axis marginal rays and chief rays at the wide-angle end, thereby reducing coma aberration and ghosts.

[0085] The preferable arrangement of the flare cut aperture FC described above is not limited to that in the first embodiment, and in the second to eighth embodiments as well, coma aberration and ghosts can be reduced by using a similar arrangement.

[0086] [Example 2] The zoom lens L0 of the second embodiment is composed of a first lens group L1 with positive refractive power, a second lens group L2 with negative refractive power, a third lens group L3 with negative refractive power, and a rear group LR with positive refractive power at the wide-angle end, which are arranged in this order from the object side to the image side. The rear group LR is composed of a fourth lens group L4 with positive refractive power, a fifth lens group L5 with negative refractive power, a sixth lens group L6 with negative refractive power, and a seventh lens group L7 with positive refractive power, which are arranged in this order from the object side to the image side. By reducing the number of lens groups compared to the first embodiment, it is easier to suppress the fluctuation of aberration caused by the relative decentering of each lens group during zooming.

[0087] [Example 3] The zoom lens L0 of the third embodiment is composed of a first lens group L1 with positive refractive power, a second lens group L2 with positive refractive power, a third lens group L3 with negative refractive power, and a rear lens group LR with positive refractive power at the wide-angle end, which are arranged in this order from the object side to the image side. The rear lens group LR is composed of a fourth lens group L4 with positive refractive power, a fifth lens group L5 with negative refractive power, a sixth lens group L6 with negative refractive power, and a seventh lens group L7 with positive refractive power, which are arranged in this order from the object side to the image side. The second lens group L2 has positive refractive power, which makes it easier to suppress fluctuations in spherical aberration and the like that occur especially during zooming.

[0088] [Example 4] In the zoom lens L0 of the fourth embodiment, the third lens unit L3 is fixed during zooming, which makes it possible to suppress decentering of the third lens unit L3 that occurs during zooming and to easily reduce fluctuations in various aberrations.

[0089] [Example 5] The zoom lens L0 of the fifth embodiment is composed of a first lens group L1 with positive refractive power, a second lens group L2 with negative refractive power, a third lens group L3 with negative refractive power, and a rear group LR with positive refractive power at the wide-angle end, which are arranged in this order from the object side to the image side. The rear group LR is composed of a fourth lens group L4 with positive refractive power, a fifth lens group L5 with negative refractive power, and a sixth lens group L6 with positive refractive power. By reducing the number of lens groups compared to the first embodiment, it becomes easier to suppress the fluctuation of aberration caused by the relative decentering of each lens group during zooming.

[0090] The sixth lens unit L6 has an aspheric lens, which makes it easier to suppress fluctuations in field curvature and distortion that occur during zooming.

[0091] [Example 6] In the zoom lens L0 of the sixth embodiment, the third lens group L3 is fixed during zooming. This makes it easier to suppress decentering of the third lens group L3 that occurs during zooming and to reduce fluctuations in various aberrations. In addition, the second lens group L2 has three lenses, which makes it easier to suppress fluctuations in field curvature and the like that occur during zooming.

[0092] [Example 7] In the zoom lens L0 of Example 7, the eighth lens unit L8 is fixed during zooming, which makes it possible to suppress decentering of the eighth lens unit L8 that occurs during zooming and to easily reduce fluctuations in various aberrations.

[0093] [Example 8] In the zoom lens L0 of the eighth embodiment, the third lens unit L3 and the sixth lens unit L6 move toward the image side along different trajectories during focusing, thereby suppressing fluctuations in various aberrations that occur during focusing.

[0094] In the zoom lens L0 of each embodiment, it is more preferable that any lens surface is aspheric. This makes it possible to suppress fluctuations in spherical aberration, curvature of field, and the like during zooming. In particular, it is even more preferable to make the lens on the image side of the aperture stop SP aspheric, since this makes it possible to suppress deterioration of coma aberration and curvature of field due to manufacturing errors in the aspheric surface.

[0095] In the zoom lens L0 of each embodiment, the first lens group L1 or the second lens group L2 preferably includes one or more positive lenses made of a material with an Abbe number of 80 or more and 100 or less. This allows for good correction of axial chromatic aberration at the telephoto end. More preferably, the zoom lens L0 includes one or more positive lenses made of a material with an Abbe number of 90 or more and 96 or less.

[0096] In the zoom lens L0 of each embodiment, it is preferable that the material of at least one of the positive lenses in the first lens group L1 has a specific gravity of 3.0 or less and an Abbe number of 65 or more and 100 or less.

[0097] This allows the first lens group L1 to be made lighter while effectively correcting axial chromatic aberration at the telephoto end. In the zoom lens L0 of each embodiment, the first lens G1 is Ohara's S-FSL7, with a specific gravity of 2.46. As another example, optical glass J-FK5 with a specific gravity of 2.45 may be used, but is not limited to this.

[0098] In the zoom lens L0 of each embodiment, it is preferable that the Abbe number of the material of the negative lens GN1 is not less than 25 and not more than 40. This makes it easier to correct axial chromatic aberration and lateral chromatic aberration over the entire zoom range.

[0099] In the zoom lens L0 of each embodiment, it is preferable to deposit a fluorine coating on the object side surface of the lens arranged closest to the object and the image side surface of the lens arranged closest to the image. Since the object side surface of the lens arranged closest to the object and the image side surface of the lens arranged closest to the image are likely to come into contact with the outside world, depositing a fluorine coating thereon can improve water and oil repellency, suppress flare, and obtain high optical performance. In particular, since the object side surface of the lens arranged closest to the object has a large diameter, it is preferable to deposit a fluorine coating thereon.

[0100] In the cemented lenses arranged in the zoom lens L0 of each embodiment, it is preferable that the positive lens and the negative lens constituting at least one cemented lens are bonded with an adhesive having a thickness on the optical axis of 0.005 mm or more and 0.05 mm or less. If it is less than 0.005 mm, it is easy to peel off, and if it is more than 0.03 mm, the distance on the optical axis from the surface of the cemented lens closest to the object side to the surface on the image side becomes long, so the total lens length becomes long. It is more preferable that it satisfies 0.008 mm or more and 0.02 mm or less.

[0101] At least one lens arranged in the zoom lens L0 of each embodiment is provided with an anti-reflection film for preventing reflection, and the anti-reflection film is composed of a plurality of films. Here, when the refractive index of the film closest to the air interface with respect to the d-line is Nd, it is preferable that the anti-reflection film PC has Nd of 1.32 or less. By making Nd 1.32 or less, the difference in refractive index with air can be reduced, so that it is possible to further reduce light reflection and reduce ghosting.

[0102] Specific examples of the configuration of the antireflection film PC include, but are not limited to, multilayer films formed using a wet method, as described in JP-A-2012-230211, JP-A-2014-95877, etc. More preferably, Nd is set to 1.30 or less to further reduce ghosts.

[0103] Here, it is preferable to provide an anti-reflection coating PC on the image side of the negative lenses arranged in the zoom lens L0, the negative lenses having a concave surface facing the image side. Light reflected by a negative lens having a concave surface facing the image side is likely to be reflected at a large angle with respect to the normal direction of the surface of the negative lens having a concave surface facing the image side, and therefore the reflectance is likely to be high. In addition, light reflected by a negative lens having a concave surface facing the image side is likely to be focused on the image plane, and therefore ghosts are likely to be noticeable. Therefore, ghosts can be reduced by providing an anti-reflection coating PC on the image side of a negative lens having a concave surface facing the image side.

[0104] Numerical examples 1 to 8 corresponding to the first to eighth embodiments, respectively, are shown below.

[0105] In the surface data of each numerical example, r represents the radius of curvature of each optical surface, and d (mm) represents the axial spacing (distance on the optical axis) between the mth surface and the (m+1)th surface. Here, m is the surface number counted from the light incident side. In addition, nd represents the refractive index of each optical member with respect to the d-line, and νd represents the Abbe number of the optical member. The Abbe number νd of a certain material is given by Nd, NF, and NC, respectively, when the refractive indices at the Fraunhofer lines d-line (wavelength 587.6 nm), F-line (wavelength 486.1 nm), C-line (wavelength 656.3 nm), and g-line (wavelength 435.8 nm) are: νd=(Nd-1) / (NF-NC) It is expressed as:

[0106] The back focus BF is the distance from the final lens surface to the image plane. The total lens length is the sum of the back focus and the distance from the first lens surface to the final lens surface.

[0107] If the optical surface is aspheric, a * symbol is added to the right of the surface number. The aspheric shape is expressed as follows, where X is the displacement from the apex of the surface in the optical axis direction, h is the height from the optical axis in a direction perpendicular to the optical axis, R is the paraxial radius of curvature, k is the conic constant, and A4, A6, A8, and A10 are the aspheric coefficients of each order: x=(h 2 / R) / [1+{1-(1+k)(h / R) 2} 1 / 2 ]+A4×h4 +A6×h 6 +A8×h 8 +A10×h 10 In addition, "e±XX" in each aspheric coefficient is "×10± XX " It means.

[0108] The lens arrangement length represents the distance on the optical axis from the surface closest to the object side to the surface closest to the image side in each lens group.

[0109] An FC (not shown) denotes a flare cut diaphragm for cutting unnecessary light. When FC is written on the m-th surface, it means that a flare cut diaphragm is disposed between the m-th surface and the (m+1)-th surface.

[0110] [Numerical Example 1] Unit: mm Surface Data Surface number rd nd νd Effective diameter 1 170.806 11.52 1.48749 70.2 89.81 2 -394.114 29.08 89.29 3 157.819 10.80 1.43387 95.1 75.42 4 -223.673 2.00 1.72047 34.7 74.11 5(FC)805.986 (variable) 72.44 6 110.937 4.80 1.64769 33.8 54.28 7 217.526 1.80 1.72916 54.7 52.89 8(FC)86.185 (variable) 51.07 9 957.252 1.65 1.72916 54.7 47.82 10 158.741 4.75 47.18 11 -101.332 1.65 1.69680 55.5 47.15 12 117.664 3.18 1.84666 23.8 47.94 13(FC)640.828 (variable) 48.02 14 78.130 7.53 1.49700 81.5 48.97 15 -203.211 0.15 48.78 16 68.586 5.52 1.49700 81.5 47.26 17 532.441 0.20 46.51 18 58.838 7.09 1.49700 81.5 44.17 19 -222.977 1.50 1.85150 40.8 43.02 20 97.389 4.86 40.77 21(Aperture) ∞ 18.11 39.35 22 76.887 5.90 1.85478 24.8 29.15 23 -41.187 1.40 2.00100 29.1 28.22 24 31.126 4.09 25.80 25 47.159 1.40 2.00069 25.5 26.35 26 29.597 4.95 1.65412 39.7 25.84 27 -378.885 (variable) 25.76 28 35.744 6.15 1.56732 42.8 25.24 29 -49.358 0.20 24.44 30 -116.989 1.20 1.80400 46.5 23.33 31 36.862 3.16 1.58144 40.8 21.98 32 -1748.879 (variable) 21.47 33 306.743 1.83 1.62280 57.0 20.12 34 -98.774 1.20 1.49700 81.5 19.67 35 28.966 (variable) 18.30 36 -496.398 2.02 1.66565 35.6 17.56 37 -46.067 3.87 17.63 38 -36.886 1.30 1.71300 53.9 17.58 39(FC) 56.282 (variable) 18.19 40 -448.749 4.64 1.65412 39.7 41.82 41 -64.608 (variable) 42.26 42 ∞ 1.30 1.51633 64.1 50.00 43 ∞ 0.80 50.00 Image plane ∞ Various data Zoom ratio 3.15 Focal length 185.00 300.00 582.00 F-number 5.15 5.70 6.48 Half angle of view 6.67 4.12 2.13 Image height 21.64 21.64 21.64 Lens total length 329.56 329.56 329.56 BF 39.56 39.56 39.56 d 5 1.80 16.70 39.92 d 8 6.17 13.42 13.57 d13 90.07 51.71 1.40 d27 2.96 2.31 1.70 d32 6.34 7.47 2.10 d35 4.53 4.07 11.28 d39 18.62 34.82 60.52 d41 37.90 37.90 37.90 Zoom lens group data Group starting plane Focal length Lens length Front principal point position Rear principal point position L1 1 214.23 53.40 3.21 -41.76 L2 6 -486.51 6.60 15.73 11.41 L3 9 -91.78 11.24 4.26 -4.07 L4 14 100.36 62.70 -48.89 -68.87 L5 28 66.71 10.72 -0.65 -7.37 L6 33 -72.61 3.03 2.29 0.36 L7 36 -57.67 7.19 8.85 2.61 L8 40 114.84 4.64 3.26 0.47 Single lens data Lens starting surface focal length 1 1 246.08 2 3 215.11 3 4 -242.82 4 6 343.47 5 7 -196.89 6 9 -261.21 7 11 -77.89 8 12 169.76 9 14 114.56 10 16 157.78 11 18 94.46 12 19 -79.43 13 22 32.12 14 23 -17.54 15 25 -82.72 16 26 42.17 17 28 37.52 18 30 -34.74 19 31 62.13 20 33 120.17 21 34 -44.93 22 36 76.15 23 38 -31.07 24 40 114.84

[0111] [Numerical Example 2] Unit: mm Surface Data Surface number rd nd νd Effective diameter 1 194.596 9.09 1.48749 70.2 89.81 2 -847.706 0.20 89.40 3 358.793 5.10 1.49700 81.5 88.24 4 -9722.189 43.61 87.62 5 164.846 8.91 1.43387 95.1 67.93 6 -232.134 2.00 1.66565 35.6 66.69 7(FC)299.163 (variable) 64.75 8 86.451 2.46 1.84666 23.8 46.26 9 134.316 1.80 1.77250 49.6 45.67 10 72.113 3.54 44.14 11 2673.406 1.65 1.77250 49.6 44.09 12(FC)130.175 (variable) 43.44 13 -114.555 1.65 1.72916 54.7 43.04 14 94.135 3.40 1.85883 30.0 43.77 15(FC)578.623 (variable) 43.86 16 100.358 5.47 1.49700 81.5 45.65 17 -262.039 0.15 45.62 18 62.075 6.19 1.43700 95.1 45.01 19 14246.998 0.20 44.40 20 50.974 6.48 1.49700 81.5 42.25 21 -1348.868 1.50 1.91082 35.2 41.21 22 104.784 16.40 39.61 23(Aperture) ∞ 6.83 32.12 24 85.940 6.50 1.85478 24.8 28.00 25 -41.040 1.40 2.00100 29.1 26.66 26 31.921 3.42 24.60 27 46.614 1.40 2.05090 26.9 24.98 28 28.770 4.69 1.70154 41.2 24.47 29 -336.143 1.70 24.35 30 35.709 5.42 1.62004 36.3 23.69 31 -54.260 1.37 22.89 32 -103.671 1.20 1.80400 46.5 20.85 33 29.018 2.68 1.65412 39.7 19.49 34 77.015 (variable) 18.90 35 -266.666 2.30 1.69350 53.2 17.41 36 -35.138 1.20 1.59282 68.6 17.07 37 31.939 (variable) 16.13 38 -64.597 1.30 1.49700 81.5 26.74 39(FC)-178.602 (variable) 27.45 40 960.057 4.31 1.66565 35.6 40.97 41 -83.955 (variable) 41.00 42 ∞ 1.30 1.54400 66.3 50.00 43 ∞ 0.80 50.00 Image plane ∞ Various data Zoom ratio 2.85 Focal length 204.00 350.00 582.00 F-number 5.15 5.70 6.48 Half angle of view 6.05 3.54 2.13 Image height 21.64 21.64 21.64 Lens total length 344.54 344.54 344.54 BF 49.54 47.39 45.54 d 7 2.60 28.53 47.44 d12 6.06 8.29 8.86 d15 84.08 41.39 1.40 d34 2.75 5.30 2.75 d37 32.01 30.04 40.92 d39 2.00 18.10 32.13 d41 47.90 45.75 43.90 Zoom lens group data Group starting plane Focal length Lens length Front principal point position Rear principal point position L1 1 239.65 68.91 -9.07 -65.67 L2 8 -147.68 9.45 9.64 2.55 L3 13 -154.18 5.05 0.43 -2.34 L4 16 66.96 72.99 -3.88 -56.16 L5 35 -54.50 3.50 1.92 -0.18 L6 38 -204.39 1.30 -0.49 -1.37 L7 40 116.17 4.31 2.38 -0.21 Single lens data Lens starting surface focal length 1 1 325.58 2 3 696.34 3 5 223.69 4 6 -196.07 5 8 279.93 6 9 -204.15 7 11 -177.19 8 13 -70.63 9 14 130.48 10 16 146.74 11 18 142.65 12 20 98.98 13 21 -106.70 14 24 33.28 15 25 -17.77 16 27 -74.51 17 28 37.98 18 30 35.55 19 32 -28.09 20 33 69.64 21 35 58.12 22 36 -28.04 23 38 -204.39 24 40 116.17

[0112] [Numerical Example 3] Unit: mm Surface Data Surface number rd nd νd Effective diameter 1 171.183 11.80 1.48749 70.2 89.81 2(FC)-365.868 (variable) 89.27 3 156.403 10.88 1.43875 94.7 73.06 4 -174.417 2.00 1.72047 34.7 71.89 5(FC)1520.907 (variable) 70.21 6 1457.410 1.65 1.72916 54.7 50.42 7 90.618 6.26 49.14 8 -116.957 1.65 1.61997 63.9 49.12 9 101.643 3.39 1.96300 24.1 50.08 10(FC) 341.950 (variable) 50.10 11 80.016 7.53 1.43700 95.1 50.93 12 -251.597 0.15 50.75 13 75.326 5.81 1.49700 81.5 49.57 14 1255.391 0.20 48.89 15 56.201 7.88 1.49700 81.5 46.23 16 -237.070 1.50 1.80400 46.5 45.02 17 107.504 11.75 42.68 18(Aperture) ∞ 13.02 37.17 19 121.140 4.48 1.84666 23.8 29.19 20 -53.408 1.40 2.00100 29.1 28.49 21 34.485 4.20 26.48 22 49.075 1.40 2.05090 26.9 26.98 23 31.559 6.00 1.65412 39.7 26.45 24 -384.167 3.57 26.29 25 41.062 5.54 1.60342 38.0 25.48 26 -56.350 0.20 24.78 27 -111.876 1.20 1.90366 31.3 23.94 28 33.303 4.68 1.77047 29.7 22.71 29 -705.298 (variable) 21.99 30 115.786 1.90 1.61340 44.3 20.41 31 -722.133 1.10 1.59282 68.6 19.84 32 31.234 (variable) 18.74 33 -166.953 1.81 1.73037 32.2 18.75 34 -49.201 6.18 18.94 35 -38.662 1.30 1.77250 49.6 18.94 36(FC) 85.508 (variable) 19.61 37 2295.727 4.64 1.66565 35.6 41.97 38 -76.977 (variable) 42.35 39 ∞ 1.30 1.51633 64.1 50.00 40 ∞ 0.80 50.00 Image plane ∞ Various data Zoom ratio 3.15 Focal length 185.00 300.00 582.00 F-number 5.15 5.70 6.48 Half angle of view 6.67 4.12 2.13 Image height 21.64 21.64 21.64 Lens total length 329.56 329.56 329.56 BF 42.03 42.03 42.03 d2 23.56 30.24 34.26 d 5 3.70 23.66 44.96 d10 93.66 54.53 1.40 d29 8.19 9.09 2.10 d32 7.24 4.20 11.25 d36 16.11 30.75 58.50 d38 40.37 40.37 40.37 Zoom lens group data Group starting plane Focal length Lens length Front principal point position Rear principal point position L1 1 240.96 11.80 2.55 -5.44 L2 3 1313.47 12.88 -21.48 -29.73 L3 6 -79.71 12.96 3.71 -6.10 L4 11 75.79 80.50 28.44 -61.33 L5 30 -74.26 3.00 2.63 0.74 L6 33 -59.61 9.29 11.85 3.25 L7 37 111.98 4.64 2.70 -0.09 Single lens data Lens starting surface focal length 1 1 240.96 2 3 189.85 3 4 -217.08 4 6 -132.59 5 8 -87.46 6 9 149.16 7 11 139.89 8 13 160.97 9 15 92.23 10 16 -91.82 11 19 44.30 12 20 -20.77 13 22 -87.73 14 23 44.84 15 25 40.22 16 27 -28.29 17 28 41.39 18 30 162.82 19 31 -50.48 20 33 94.90 21 35 -34.31 22 37 111.98

[0113] [Numerical Example 4] Unit: mm Surface Data Surface number rd nd νd Effective diameter 1 158.077 11.31 1.48749 70.2 89.22 2 -509.174 21.59 88.65 3 125.655 11.09 1.43387 95.1 77.50 4 -391.341 2.00 1.66565 35.6 76.07 5(FC)465.930 (variable) 74.15 6 110.080 1.65 1.61997 63.9 47.90 7 67.228 6.32 46.40 8 -142.124 1.65 1.72916 54.7 46.30 9 68.545 4.91 1.84666 23.8 45.97 10(FC)321.092 (variable) 45.81 11 -171.311 1.80 1.90366 31.3 45.70 12(FC)463.335 (variable) 46.12 13 92.510 7.28 1.49700 81.5 49.24 14 -162.381 0.15 49.26 15 77.224 6.55 1.49700 81.5 48.44 16 -436.402 0.20 47.83 17 54.618 8.24 1.49700 81.5 44.83 18 -160.002 1.50 1.83481 42.7 43.57 19 104.805 4.75 41.25 20(Aperture) ∞ 18.00 39.87 21 81.974 6.01 1.85478 24.8 29.97 22 -41.584 1.40 2.00100 29.1 29.07 23 33.797 4.92 26.71 24 50.482 1.40 2.00069 25.5 27.32 25 31.689 4.85 1.65412 39.7 26.80 26 -523.338 (variable) 26.71 27 41.853 6.12 1.54814 45.8 26.23 28 -47.351 0.20 25.53 29 -94.947 1.20 1.69680 55.5 24.49 30 26.092 3.80 1.65412 39.7 22.77 31 138.243 (variable) 22.19 32 145.141 1.80 1.61340 44.3 20.89 33 -188.510 1.20 1.59282 68.6 20.49 34 38.372 (variable) 19.54 35 335.097 2.31 1.61340 44.3 17.32 36 -45.404 4.40 17.48 37 -36.559 1.30 1.77250 49.6 17.27 38(FC) 60.896 (variable) 17.81 39 -181.598 4.14 1.73800 32.3 40.53 40 -57.611 (variable) 41.04 41 ∞ 1.30 1.51633 64.1 50.00 42 ∞ 0.80 50.00 Image plane ∞ Various data Zoom ratio 3.35 Focal length 204.00 300.00 682.50 F-number 5.15 5.70 7.65 Half angle of view 6.05 4.12 1.82 Image height 21.64 21.64 21.64 Lens total length 344.56 344.56 344.56 BF 44.71 44.71 44.71 d 5 19.84 32.40 51.33 d10 36.84 24.28 5.35 d12 56.48 41.63 1.40 d26 2.89 2.11 1.94 d31 7.57 8.28 2.10 d34 3.62 3.62 27.83 d38 18.59 33.50 55.88 d40 43.05 43.05 43.05 Zoom lens group data Group starting plane Focal length Lens length Front principal point position Rear principal point position L1 1 184.67 45.99 6.16 -31.94 L2 6 -102.59 14.53 6.39 -4.47 L3 11 -138.22 1.80 0.25 -0.69 L4 13 78.74 65.24 -34.53 -62.10 L5 27 87.80 11.32 -2.30 -9.18 L6 32 -90.98 3.00 2.61 0.72 L7 35 -61.78 8.01 11.44 4.12 L8 39 112.74 4.14 3.44 1.09 Single lens data Lens starting surface focal length 1 1 248.83 2 3 220.66 3 4 -319.23 4 6 -282.73 5 8 -63.21 6 9 102.02 7 11 -138.22 8 13 119.72 9 15 132.58 10 17 82.99 11 18 -75.66 12 21 33.02 13 22 -18.45 14 24 -88.36 15 25 45.84 16 27 41.54 17 29 -29.25 18 30 48.52 19 32 133.96 20 33 -53.67 21 35 65.34 22 37 -29.40 23 39 112.74

[0114] [Numerical Example 5] Unit: mm Surface Data Surface number rd nd νd Effective diameter 1 173.604 7.74 1.48749 70.2 74.85 2 -668.668 0.20 74.47 3 260.347 5.10 1.49700 81.5 73.43 4 -4188.383 25.29 72.78 5 138.054 8.19 1.43387 95.1 60.49 6 -234.104 2.00 1.66565 35.6 59.21 7(FC) 210.639 (variable) 57.27 8 85.023 2.26 1.84666 23.8 37.21 9 154.793 1.80 1.81600 46.6 36.69 10(FC) 60.709 (variable) 35.32 11 -324.229 1.65 1.72916 54.7 33.56 12 158.255 2.75 33.26 13 -82.052 1.65 1.72916 54.7 33.26 14 92.545 2.70 1.85478 24.8 34.06 15(FC)2019.792 (variable) 34.21 16 71.137 4.64 1.49700 81.5 36.20 17 -351.943 0.15 36.18 18 55.256 5.28 1.43700 95.1 35.91 19 -522.509 0.20 35.40 20 43.993 5.74 1.49700 81.5 33.83 21 -442.271 1.50 1.91082 35.2 32.71 22 90.035 8.79 31.43 23 (Aperture) ∞ 5.60 28.14 24 83.679 6.50 1.85478 24.8 25.22 25 -37.048 1.40 2.00100 29.1 23.87 26 32.685 3.28 22.29 27 49.481 1.40 2.05090 26.9 22.63 28 28.848 4.09 1.74400 44.8 22.22 29 -280.577 1.70 22.11 30 40.975 4.74 1.66565 35.6 21.53 31 -44.897 0.59 20.87 32 -55.492 1.20 1.77250 49.6 19.97 33 106.409 (variable) 19.14 34 -257.743 2.83 1.63930 44.9 16.64 35 -25.508 1.20 1.59282 68.6 16.65 36(FC) 30.852 (variable) 16.62 37* -93.406 2.00 1.58313 59.4 29.36 38 81.856 6.64 1.53172 48.8 30.88 39 -53.407 (variable) 34.00 40 ∞ 1.30 1.54400 66.3 50.00 41 ∞ 0.80 50.00 Image plane ∞ Aspheric Data Page 37 K = 0.00000e+00 A 4=-5.61235e-07 A 6= 3.23010e-09 A 8=-1.63969e-11 A10= 3.48666e-14 Various data Zoom ratio 3.88 Focal length 125.00 250.00 485.00 F-number 5.15 5.70 6.48 Half angle of view 9.82 4.95 2.55 Image height 21.64 21.64 21.64 Lens length 299.54 299.54 299.54 BF 64.13 57.60 51.99 d 7 2.60 35.11 53.96 d10 5.56 7.66 10.06 d15 82.38 39.99 1.40 d33 2.61 8.27 10.15 d36 11.47 20.12 41.18 d39 62.49 55.96 50.35 Zoom lens group data Group starting plane Focal length Lens length Front principal point position Rear principal point position L1 1 203.74 48.52 -8.78 -46.56 L2 8 -295.40 4.06 8.86 6.45 L3 11 -66.75 8.75 2.25 -3.83 L4 16 54.68 56.80 5.95 -41.31 L5 34 -50.11 4.03 2.23 -0.24 L6 37 289.42 8.64 15.91 10.91 Single lens data Lens starting surface focal length 1 1 283.57 2 3 493.37 3 5 201.50 4 6 -166.27 5 8 219.54 6 9 -123.47 7 11 -145.64 8 13 -59.41 9 14 113.39 10 16 119.50 11 18 114.67 12 20 80.83 13 21 -82.02 14 24 30.81 15 25 -17.18 16 27 -68.20 17 28 35.36 18 30 32.91 19 32 -47.06 20 34 44.07 21 35 -23.37 22 37 -74.50 23 38 61.84

[0115] [Numerical Example 6] Unit: mm Surface Data Surface number rd nd νd Effective diameter 1 185.136 10.53 1.48749 70.2 89.81 2 -468.666 11.50 89.35 3 135.136 9.87 1.43387 95.1 82.49 4 -1482.456 2.00 1.73800 32.3 81.26 5(FC)678.705 (variable) 79.98 6 92.605 1.65 1.72916 54.7 54.06 7 72.502 6.83 52.64 8 -214.838 1.65 1.72916 54.7 52.53 9 65.101 5.45 1.84666 23.8 51.51 10(FC)200.453 (variable) 51.21 11 -134.322 1.80 1.90366 31.3 50.95 12(FC)564.979 (variable) 51.61 13 113.990 7.71 1.49700 81.5 52.98 14 -141.886 0.15 53.11 15 82.813 7.03 1.49700 81.5 52.49 16 -447.028 0.20 51.93 17 55.599 9.22 1.49700 81.5 48.72 18 -176.696 1.50 1.83481 42.7 47.44 19 115.041 4.92 45.01 20(Aperture) ∞ 20.19 43.64 21 78.019 6.51 1.85478 24.8 32.57 22 -47.199 1.40 2.00100 29.1 31.60 23 33.910 4.96 28.86 24 50.532 1.40 2.00069 25.5 29.58 25 31.163 5.54 1.67300 38.3 28.99 26 -644.614 (variable) 28.89 27 41.737 6.53 1.61340 44.3 28.34 28 -54.673 0.20 27.55 29 -122.333 1.20 1.80400 46.5 26.26 30 30.744 3.56 1.72047 34.7 24.43 31 151.153 (variable) 23.84 32 165.525 1.58 1.71700 47.9 22.70 33 -479.514 1.20 1.59282 68.6 22.30 34 36.614 (variable) 21.10 35 502.145 2.05 1.66565 35.6 17.98 36 -56.738 5.63 18.02 37 -42.218 1.30 1.81600 46.6 17.59 38 59.727 (variable) 18.10 39 -400.292 4.50 1.73800 32.3 42.45 40(FC)-67.000 (variable) 42.90 41 ∞ 1.30 1.54400 66.3 50.00 42 ∞ 0.80 50.00 Image plane ∞ Various data Zoom ratio 3.15 Focal length 185.00 300.00 582.00 F-number 5.15 5.70 6.48 Half angle of view 6.67 4.12 2.13 Image height 21.64 21.64 21.64 Lens total length 329.54 329.54 329.54 BF 42.04 42.04 42.04 d 5 10.53 27.85 47.53 d10 44.08 26.76 7.08 d12 51.92 32.56 1.40 d26 3.28 2.17 1.72 d31 4.67 6.48 2.10 d34 4.82 3.94 17.83 d38 18.43 37.97 60.08 d40 40.40 40.40 40.40 Zoom lens group data Group starting plane Focal length Lens length Front principal point position Rear principal point position L1 1 181.06 33.90 6.04 -20.65 L2 6 -124.70 15.59 8.77 -2.88 L3 11 -119.94 1.80 0.18 -0.76 L4 13 76.01 70.74 -31.21 -63.60 L5 27 80.91 11.49 -2.34 -9.03 L6 32 -87.10 2.78 2.34 0.65 L7 35 -57.06 8.98 12.56 4.08 L8 39 108.41 4.50 3.09 0.52 Single lens data Lens starting surface focal length 1 1 273.68 2 3 285.97 3 4 -630.59 4 6 -474.45 5 8 -68.35 6 9 111.81 7 11 -119.94 8 13 128.47 9 15 141.20 10 17 86.23 11 18 -83.27 12 21 35.25 13 22 -19.54 14 24 -84.30 15 25 44.32 16 27 39.61 17 29 -30.45 18 30 52.91 19 32 171.79 20 33 -57.33 21 35 76.70 22 37 -30.14 23 39 108.41

[0116] [Numerical Example 7] Unit: mm Surface Data Surface number rd nd νd Effective diameter 1 150.309 11.96 1.48749 70.2 89.81 2 -481.314 31.52 89.20 3 131.122 11.14 1.43387 95.1 73.61 4 -245.600 2.00 1.72047 34.7 72.14 5(FC)467.037 (variable) 70.21 6 127.182 3.62 1.73037 32.2 49.66 7 361.846 1.80 1.72916 54.7 48.80 8(FC)72.346 (variable) 46.72 9 -2309.514 1.65 1.72916 54.7 44.23 10 330.094 3.52 43.89 11 -92.981 1.65 1.69680 55.5 43.87 12 97.379 3.08 1.84666 23.8 44.68 13(FC)364.057 (variable) 44.76 14 66.257 7.78 1.49700 81.5 45.90 15 -180.827 0.15 45.70 16 75.550 4.81 1.49700 81.5 44.38 17 874.213 0.20 43.71 18 52.221 7.56 1.49700 81.5 41.39 19 -147.505 1.50 1.85150 40.8 40.14 20 93.480 4.64 37.93 21(Aperture) ∞ 14.72 36.60 22 74.302 6.23 1.85478 24.8 28.64 23 -36.705 1.40 2.00100 29.1 27.68 24 31.093 3.56 25.34 25 46.201 1.40 2.00069 25.5 25.87 26 28.960 4.92 1.65412 39.7 25.39 27 -365.718 (variable) 25.33 28 36.475 6.16 1.56732 42.8 24.89 29 -45.198 0.20 24.14 30 -98.335 1.20 1.80400 46.5 23.03 31 32.069 3.26 1.65412 39.7 21.65 32 504.250 (variable) 21.15 33 193.985 1.58 1.62280 57.0 19.93 34 -200.000 1.20 1.49700 81.5 19.53 35 31.124 (variable) 18.38 36 -256.193 2.00 1.66565 35.6 18.37 37 -45.934 5.20 18.45 38 -35.265 1.30 1.71300 53.9 17.67 39(FC) 60.693 (variable) 18.05 40 -336.312 4.54 1.65412 39.7 40.26 41 -59.940 (variable) 40.75 42 ∞ 1.30 1.51633 64.1 50.00 43 ∞ 0.80 50.00 Image plane ∞ Various data Zoom ratio 3.77 Focal length 154.50 300.00 582.00 F-number 5.15 5.70 6.48 Half angle of view 7.97 4.12 2.13 Image height 21.64 21.64 21.64 Lens total length 329.56 329.56 329.56 BF 44.56 44.56 44.56 d 5 1.80 23.69 44.51 d 8 6.58 16.02 13.98 d13 95.54 45.60 1.40 d27 2.79 1.90 1.84 d32 2.10 6.02 2.10 d35 4.05 4.05 12.36 d39 14.69 30.27 51.36 d41 42.90 42.90 42.90 Zoom lens group data Group starting plane Focal length Lens length Front principal point position Rear principal point position L1 1 204.41 56.63 2.44 -45.17 L2 6 -240.49 5.42 7.59 4.32 L3 9 -91.55 9.91 4.03 -3.04 L4 14 87.16 58.86 -39.92 -60.74 L5 28 70.17 10.83 -1.08 -7.73 L6 33 -83.11 2.78 2.30 0.52 L7 36 -54.93 8.50 10.67 2.94 L8 40 110.79 4.54 3.32 0.59 Single lens data Lens starting surface focal length 1 1 236.43 2 3 198.81 3 4 -223.14 4 6 266.78 5 7 -124.34 6 9 -395.99 7 11 -68.02 8 12 156.19 9 14 98.60 10 16 166.06 11 18 78.59 12 19 -67.01 13 22 29.51 14 23 -16.64 15 25 -80.83 16 26 41.23 17 28 36.58 18 30 -29.95 19 31 52.21 20 33 158.36 21 34 -54.10 22 36 83.76 23 38 -31.11 24 40 110.79

[0117] [Numerical Example 8] Unit: mm Surface Data Surface number rd nd νd Effective diameter 1 156.049 11.59 1.48749 70.2 89.82 2 -496.261 30.48 89.23 3 145.397 10.56 1.43387 95.1 74.81 4 -264.253 2.00 1.74951 35.3 73.48 5(FC)691.229 (variable) 71.86 6 104.105 3.00 1.75520 27.5 57.27 7 168.323 1.80 1.72916 54.7 56.40 8 89.864 3.50 54.10 9 451.643 1.65 1.83481 42.7 54.02 10(FC)118.638 (variable) 52.51 11 -113.512 1.65 1.69680 55.5 44.19 12 90.699 2.81 1.92119 24.0 44.67 13(FC)226.240 (variable) 44.68 14 90.565 6.04 1.43700 95.1 45.29 15 -209.408 0.15 45.25 16 59.188 6.07 1.49700 81.5 44.50 17 1009.241 0.20 43.81 18 44.835 6.63 1.49700 81.5 41.26 19 2019.829 1.50 1.91082 35.2 40.11 20 108.557 9.77 38.47 21(Aperture) ∞ 7.71 32.99 22 117.629 6.50 1.84666 23.8 27.21 23 -42.821 1.40 2.00100 29.1 25.44 24 29.226 3.38 23.28 25 41.959 1.40 2.05090 26.9 23.56 26 27.197 4.39 1.65412 39.7 23.00 27 -493.461 (variable) 22.85 28 42.301 4.96 1.59551 39.2 21.95 29 -41.477 0.20 21.32 30 -74.047 1.20 1.80400 46.5 20.53 31 26.655 3.40 1.65412 39.7 19.32 32 1794.563 (variable) 18.87 33 180.718 2.25 1.61340 44.3 17.50 34 -66.401 1.20 1.59282 68.6 16.99 35 28.364 (variable) 15.98 36 -42.457 1.30 1.49700 81.5 21.41 37(FC)449.975 (variable) 22.33 38 -1546.985 5.41 1.61340 44.3 38.27 39 -56.851 (variable) 41.00 40 ∞ 1.30 1.54400 66.3 50.00 41 ∞ 0.80 50.00 Image plane ∞ Various data Zoom ratio 3.15 Focal length 185.00 300.00 582.00 F-number 5.15 5.70 6.48 Half angle of view 6.67 4.12 2.13 Image height 21.64 21.64 21.64 Lens total length 329.54 329.54 329.54 BF 45.54 45.54 46.21 d 5 2.60 23.85 44.94 d10 28.76 31.57 25.72 d13 80.42 45.22 1.40 d27 3.02 2.84 4.21 d32 8.20 9.79 2.10 d35 14.88 13.16 30.01 d37 2.00 13.45 30.85 d39 43.90 43.90 44.56 Zoom lens group data Group starting plane Focal length Lens length Front principal point position Rear principal point position L1 1 208.29 54.63 3.87 -42.49 L2 6 -168.15 9.95 10.39 2.97 L3 11 -128.74 4.46 0.97 -1.46 L4 14 85.44 55.16 -46.35 -59.18 L5 28 84.24 9.76 -1.32 -7.25 L6 33 -58.68 3.45 2.61 0.44 L7 36 -77.99 1.30 0.07 -0.79 L8 38 96.08 5.41 3.48 0.13 Single lens data Lens starting surface focal length 1 1 244.96 2 3 217.87 3 4 -254.83 4 6 354.20 5 7 -266.98 6 9 -193.18 7 11 -72.11 8 12 162.72 9 14 145.57 10 16 126.24 11 18 92.16 12 19 -126.00 13 22 37.78 14 23 -17.19 15 25 -77.32 16 26 39.54 17 28 35.96 18 30 -24.25 19 31 41.33 20 33 79.44 21 34 -33.37 22 36 -77.99 23 38 96.08 The amount of movement of each lens group when focusing from infinity to each object distance in each numerical example is summarized in Table 1 below. In Table 1, the direction from the object side to the image side is defined as positive.

[0118] [Table 1]

[0119] The various values ​​in each numerical example are summarized in Table 2 below.

[0120] [Table 2]

[0121] The lenses that satisfy conditional expression (13) in each numerical example and their numerical values ​​are shown in Table 3 below.

[0122] [Table 3]

[0123] [Imaging device] Next, an embodiment of a digital still camera (imaging device) using the zoom lens of the present invention as an imaging optical system will be described with reference to Fig. 25. In Fig. 25, reference numeral 11 denotes an imaging optical system constituted by any of the zoom lenses described in Examples 1 to 8. Reference numeral 12 denotes an imaging element (photoelectric conversion element) such as a CCD sensor or CMOS sensor that is built into a camera body 10 and receives an optical image formed by the imaging optical system 11 and photoelectrically converts it. The camera body 10 may be a so-called single-lens reflex camera having a quick-turn mirror, or a so-called mirrorless camera having no quick-turn mirror.

[0124] In this way, by applying the zoom lens L0 of the present invention to an imaging device such as a digital still camera, it is possible to obtain a high-resolution image with a wide angle of view.

[0125] The disclosure of each embodiment includes the following configuration.

[0126] (Configuration 1) A zoom lens comprising, in order from the object side to the image side, a first lens group having positive refractive power, a second lens group, a third lens group having negative refractive power, and a rear group having one or more lens groups, in which the distance between adjacent lens groups changes during zooming, the first lens group includes a first positive lens having a positive refractive power, which does not move during zooming and is disposed closest to the object side; the rear group has positive refractive power at a wide-angle end, Let f1 be the focal length of the first lens group, f2 be the focal length of the second lens group, Lt be the total lens length at the telephoto end, and ft be the focal length of the entire system at the telephoto end. 0.05 <f1 / |f2|<2.00 0.40 <Lt / ft<0.65 A zoom lens characterized by satisfying the following conditional expressions:

[0127] (Configuration 2) 2. The zoom lens according to configuration 1, wherein the rear group has a first focus lens group that moves during focusing from infinity to a close distance.

[0128] (Configuration 3) The zoom lens according to configuration 2, wherein the first focus lens group has negative refractive power and moves toward the image side during focusing from infinity to a close distance.

[0129] (Configuration 4) the first lens group includes a first subgroup and a second subgroup arranged adjacent to the first subgroup on an image side, Among the air gaps on the optical axis between adjacent lenses in the first lens group, the air gap on the optical axis between the first sub group and the second sub group is the largest, When the distance on the optical axis between the surface of the first sub group closest to the image side and the surface of the second sub group closest to the object side is d1AB and the focal length of the first sub group is f1A, 0.02 <d1AB / f1A<0.35 4. The zoom lens according to claim 1, wherein the following condition is satisfied:

[0130] (Configuration 5) 5. The zoom lens according to any one of configurations 1 to 4, wherein the first lens group is composed of four or less lenses.

[0131] (Configuration 6) At the telephoto end, when focusing is performed at an object distance where the lateral magnification of the entire system is −0.2, the lateral magnification of the first focus lens group is βLRF1. 1.1<βLRF1<4.0 4. The zoom lens according to configuration 3, which satisfies the following condition:

[0132] (Configuration 7) At the telephoto end, when focusing is performed at an object distance where the lateral magnification of the entire system is −0.2, the lateral magnification of the first focus lens group is βLRF1, and the composite lateral magnification of all lens groups disposed on the image side of the first focus lens group is βR1. -10.0<(1-βLRF1×βLRF1)×βR1×βR1<-3.0 4. The zoom lens according to configuration 3, which satisfies the following condition:

[0133] (Configuration 8) Let sk be the smaller of the back focuses at the wide-angle end and the telephoto end, and let Lt be the total lens length at the telephoto end. 0.09 <sk / Lt<0.3 8. The zoom lens according to any one of configurations 1 to 7, wherein the following condition is satisfied:

[0134] (Configuration 9) Let fLP be the focal length of the lens group having positive refractive power arranged in the rear group and located closest to the object side. 1.2 <f1 / fLP<6.0 9. The zoom lens according to any one of configurations 1 to 8, which satisfies the following conditional expression:

[0135] (Configuration 10) When the focal length of the third lens group is f3, -5.0 <f1 / f3<-0.5 10. The zoom lens according to any one of configurations 1 to 9, wherein the following condition is satisfied:

[0136] (Configuration 11) When the radius of curvature of the object side surface of the first positive lens is r1 and the radius of curvature of the image side surface of the first positive lens is r2, 0.0<(r2+r1) / (r2-r1)<1.5 11. The zoom lens according to any one of configurations 1 to 10, which satisfies the following conditional expression:

[0137] (Configuration 12) 12. A zoom lens according to any one of configurations 1 to 11, wherein the first lens group is stationary during focusing from infinity to a close distance.

[0138] (Configuration 13) 0.1 <f1 / ft<0.8 13. The zoom lens according to any one of configurations 1 to 12, wherein the following condition is satisfied:

[0139] (Configuration 14) When the radius of curvature of the surface of the first focus lens group closest to the object side is r1LRF and the radius of curvature of the surface of the first focus lens group closest to the image side is r2LRF, -3.5<(r2LRF+r1LRF) / (r2LRF-r1LRF)<-0.2 4. The zoom lens according to configuration 3, which satisfies the following condition:

[0140] (Configuration 15) The zoom lens according to any one of configurations 1 to 14, wherein the rear group has a fourth lens group, a fifth lens group, and a sixth lens group, all of which have positive refractive power, arranged in this order from the object side to the image side.

[0141] (Configuration 16) Among the negative lenses arranged in the first lens group, the negative lens arranged closest to the object has an Abbe number of νd_N and a partial dispersion ratio for the g-line and the F-line of θgF_N. -0.01<θgF_N-(-0.0016178×νd_N+0.64146)<0.01 16. The zoom lens according to any one of configurations 1 to 15, wherein the following condition is satisfied:

[0142] (Configuration 17) the rear group has an aperture stop that determines an axial light beam, and a plurality of positive lenses arranged on the image side of the aperture stop, and when the Abbe number of at least two of the plurality of positive lenses is νd_PR and the partial dispersion ratios for the g-line and the F-line are θgF_PR, -0.012<θgF_PR-(-0.0016178×νd_PR+0.64146)<0.005 17. The zoom lens according to any one of configurations 1 to 16, wherein the following condition is satisfied:

[0143] (Configuration 18) The zoom lens described in configuration 3 is characterized in that the zoom lens has a second focus lens group, and the first focus lens group and the second focus lens group move on different trajectories during focusing from infinity to a close distance.

[0144] (Configuration 19) Of the first focus lens group and the second focus lens group, the lens group arranged on the object side is referred to as an object-side focus lens group, and the lens group arranged on the image side is referred to as an image-side focus lens group, When the focal length of the object-side focus lens group is fLF1 and the focal length of the image-side focus lens group is fLF2, 0.4 <fLF1 / fLF2<3.0 19. The zoom lens according to configuration 18, which satisfies the following condition:

[0145] (Configuration 20) Of the first focus lens group and the second focus lens group, the lens group arranged on the object side is referred to as an object-side focus lens group, and the lens group arranged on the image side is referred to as an image-side focus lens group, At the telephoto end, when focusing is performed from infinity to an object distance at which the lateral magnification of the entire system is −0.2, the absolute value of the movement amount of the object-side focus lens group is denoted as MLF1, and the absolute value of the movement amount of the image-side focus lens group is denoted as MLF2. 0.2 <MLF1 / MLF2<5.0 19. The zoom lens according to configuration 18, which satisfies the following condition:

[0146] (Configuration 21) At the telephoto end, when focusing is performed at an object distance where the lateral magnification of the entire system is −0.3, the distance on the optical axis between the surface closest to the image side of the first focus lens group and the object side surface of the lens arranged adjacent to the image side of the first focus lens group is T, the lateral magnification of the first focus lens group is βLRF2, and the composite lateral magnification of all lens groups arranged on the image side of the first focus lens group is βR2. 0.01 <T×|(1-βLRF2×βLRF2)×βR2×βR2| / f<0.50 4. The zoom lens according to configuration 3, which satisfies the following condition:

[0147] (Configuration 22) The first focus lens group has a cemented lens composed of a positive lens and a negative lens. When the Abbe number of the negative lens is νd_RF1N, 50<νd_RF1N<100 4. The zoom lens according to configuration 3, which satisfies the following condition:

[0148] (Configuration 23) The zoom lens according to configuration 4, wherein the first subgroup is composed of two or less lenses.

[0149] (Configuration 24) When the focal length of the third lens group is f3, -1000.0<|f2| / f3<-0.3 24. The zoom lens according to any one of configurations 1 to 23, characterized in that the following condition is satisfied:

[0150] (Configuration 25) When the focal length of the first focus lens group is fLRF, -1.00 <fLRF / f1<-0.05 4. The zoom lens according to configuration 3, which satisfies the following condition:

[0151] (Configuration 26) 26. An imaging apparatus comprising: the zoom lens according to any one of configurations 1 to 25; and an imaging element that receives an image formed by the zoom lens.

[0152] Although the preferred embodiments and examples of the present invention have been described above, the present invention is not limited to these embodiments and examples, and various combinations, modifications, and changes are possible within the scope of the gist of the present invention. [Explanation of symbols]

[0153] L0 Zoom Lens L1 First lens group L2 Second lens group L3: Third lens group LR rear group First positive lens: GP1

Claims

1. A zoom lens comprising a first lens group with positive refractive power, a second lens group, a third lens group with negative refractive power, and a rear group having one or more lens groups, arranged in order from the object side to the image side, wherein the spacing between adjacent lens groups changes during zooming. The first lens group has a first positive lens with positive refractive power that remains stationary during zooming and is positioned closest to the object. The first lens group consists of four or fewer lenses. The aforementioned rear group has a positive refractive power at the wide-angle end. When the focal length of the first lens group is f1, the focal length of the second lens group is f2, the total length of the lenses at the telephoto end is Lt, and the focal length of the entire system at the telephoto end is ft, 0.05<f1 / |f2|<2.00 0.40<Lt / ft<0.65 A zoom lens characterized by satisfying the following conditional equation.

2. The zoom lens according to claim 1, characterized in that the rear group has a first focusing lens group that moves when focusing from infinity to near.

3. The zoom lens according to claim 2, characterized in that the first focusing lens group has a negative refractive power and moves toward the image side when focusing from infinity to close.

4. The aforementioned first lens group consists of a first subgroup and a second subgroup arranged adjacent to the image side of the first subgroup. Of the air gaps along the optical axes of adjacent lenses in the first lens group, the air gap between the first subgroup and the second subgroup is the largest. When the distance on the optical axis between the image-side surface of the first subgroup and the object-side surface of the second subgroup is d1AB, and the focal length of the first subgroup is f1A, 0.02<d1AB / f1A<0.35 A zoom lens according to claim 1 that satisfies the following condition.

5. When focusing on an object distance at the telephoto end where the lateral magnification of the entire system is -0.2, the lateral magnification of the first focusing lens group is βLRF1, 1.1<βLRF1<4.0 The zoom lens according to claim 3, characterized in that it satisfies the following condition.

6. When focusing at the telephoto end to an object distance where the lateral magnification of the entire system is -0.2, the lateral magnification of the first focusing lens group is βLRF1, and the combined lateral magnification of all lens groups positioned on the image side of the first focusing lens group is βR1. -10.0 < (1 - βLRF1 × βLRF1) × βR1 × βR1 < -3.0 The zoom lens according to claim 3, characterized in that it satisfies the following condition.

7. When the smaller of the back focus points at the wide-angle and telephoto ends is denoted as sk, 0.09<sk / Lt<0.3 The zoom lens according to claim 1, characterized in that it satisfies the following condition.

8. When fLP is the focal length of the lens group with positive refractive power that is positioned closest to the object among the group of lenses with positive refractive power arranged in the rear group, 1.2<f1 / fLP<6.0 The zoom lens according to claim 1, characterized in that it satisfies the following condition.

9. When the focal length of the third lens group is f3, -5.0<f1 / f3<-0.5 The zoom lens according to claim 1, characterized in that it satisfies the following condition.

10. When the radius of curvature of the object-side surface of the first positive lens is r1 and the radius of curvature of the image-side surface of the first positive lens is r2, 0.0<(r2+r1) / (r2-r1)<1.5 The zoom lens according to claim 1, characterized in that it satisfies the following condition.

11. The zoom lens according to claim 1, characterized in that the first lens group remains stationary when focusing from infinity to close.

12. 0.1<f1 / ft<0.8 The zoom lens according to claim 1, characterized in that it satisfies the following condition.

13. When the radius of curvature of the object-side surface of the first focusing lens group is r1LRF and the radius of curvature of the image-side surface of the first focusing lens group is r2LRF, -3.5<(r2LRF+r1LRF) / (r2LRF-r1LRF)<-0.2 The zoom lens according to claim 3, characterized in that it satisfies the following condition.

14. The zoom lens according to claim 1, characterized in that the rear group has a fourth lens group, a fifth lens group, and a sixth lens group having positive refractive power, arranged in order from the object side to the image side.

15. When the Abbe number of the negative lens positioned closest to the object among the negative lenses arranged in the first lens group is νd_N, and the partial dispersion ratio with respect to the g-line and F-line is θgF_N, -0.01<θgF_N-(-0.0016178×νd_N+0.64146)<0.01 The zoom lens according to claim 1, characterized in that it satisfies the following condition.

16. The aforementioned rear group has an aperture diaphragm that determines the on-axial light beam, and has a plurality of positive lenses positioned on the image side of the aperture diaphragm, and when the Abbe number of at least two of the plurality of positive lenses is νd_PR and the partial dispersion ratio with respect to the g line and the F line is θgF_PR, then the at least two positive lenses are -0.012<θgF_PR-(-0.0016178×νd_PR+0.64146)<0.005 The zoom lens according to claim 1, characterized in that it satisfies the following condition.

17. The zoom lens according to claim 3, wherein the zoom lens has a second focusing lens group, and the first focusing lens group and the second focusing lens group move along different trajectories when focusing from infinity to near.

18. Of the first and second focusing lens groups, the lens group positioned on the object side is referred to as the object-side focusing lens group, and the lens group positioned on the image side is referred to as the image-side focusing lens group. When the focal length of the object-side focusing lens group is fLF1 and the focal length of the image-side focusing lens group is fLF2, 0.4<fLF1 / fLF2<3.0 The zoom lens according to claim 17, characterized in that it satisfies the following condition.

19. Of the first and second focusing lens groups, the lens group positioned on the object side is referred to as the object-side focusing lens group, and the lens group positioned on the image side is referred to as the image-side focusing lens group. When focusing at the telephoto end to an object distance from infinity to a distance where the lateral magnification of the entire system is -0.2, let MLF1 be the absolute value of the movement of the object-side focusing lens group and MLF2 be the absolute value of the movement of the image-side focusing lens group. 0.2<MLF1 / MLF2<5.0 The zoom lens according to claim 17, characterized in that it satisfies the following condition.

20. When focusing at the telephoto end to an object distance where the lateral magnification of the entire system is -0.3, the distance on the optical axis between the image-side surface of the first focusing lens group and the object-side surface of a lens adjacent to the image-side of the first focusing lens group is T, the lateral magnification of the first focusing lens group is βLRF2, and the combined lateral magnification of all lens groups positioned closer to the image than the first focusing lens group is βR2. 0.01<T×|(1-βLRF2×βLRF2)×βR2×βR2| / f<0.50 The zoom lens according to claim 3, characterized in that it satisfies the following condition.

21. The first focusing lens group has a cemented lens consisting of a positive lens and a negative lens, and when the Abbe number of the negative lens is νd_RF1N, 50<νd_RF1N<100 The zoom lens according to claim 3, characterized in that it satisfies the following condition.

22. The zoom lens according to claim 4, characterized in that the first subgroup consists of two or fewer lenses.

23. When the focal length of the third lens group is f3, -1000.0<|f2| / f3<-0.3 The zoom lens according to claim 1, characterized in that it satisfies the following condition.

24. When the focal length of the first focusing lens group is fLRF, -1.00<fLRF / f1<-0.05 The zoom lens according to claim 3, characterized in that it satisfies the following condition.

25. An imaging device characterized by having a zoom lens according to any one of claims 1 to 24 and an image sensor that receives an image formed by the zoom lens.

Images