Zoom lens and imaging device having the same

Abstract

To provide a zoom lens that achieves both widening of field angle and downsizing and is capable of maintaining high optical performance at vibration insulating, and an imaging device having the zoom lens.SOLUTION: The zoom lens includes a first lens group having negative refractive power and a rear group including at least three lens groups and having positive refractive power on the whole, arranged in order from an object side to an image side, wherein an interval between the first lens group and the rear group changes in zooming. The rear group includes a sub-group that moves in a direction including a component in a direction perpendicular to an optical axis during image blur correction, and the first lens group includes three or more negative lenses arranged in order from the object side to the image side. At least two of the three or more negative lenses have their convex surfaces facing the object side, and at least one of these has its concave surface facing the object side. A distortion amount of the maximum image height during infinity focusing at a wide angle end, a focal distance of the first lens group, and a focal distance of the last lens group arranged on the most image side are appropriately set, respectively.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a zoom lens suitable for digital video cameras, digital still cameras, broadcast cameras, cameras for silver halide film, surveillance cameras, vehicle-mounted cameras, and the like. [Background technology]

[0002] Conventionally, known means for correcting image blur include a lens-shift type vibration-reduction mechanism that shifts part of the optical system in a direction perpendicular to the optical axis, and a sensor-shift type vibration-reduction mechanism that shifts the image sensor. Patent Document 1 discloses a zoom lens equipped with a lens-shift type vibration-reduction mechanism. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-215565 Summary of the Invention [Problem to be solved by the invention]

[0004] In the zoom lens of Patent Document 1, when a large amount of correction is attempted, the amount of decentering of the image stabilization group becomes large, and when image blur is corrected, the image becomes blurred due to decentering aberrations.

[0005] Ultra-wide-angle zoom lenses with angles of view exceeding 100° often use sensor-shift vibration reduction mechanisms because a small shift can achieve a large amount of correction. Because the amount of image point movement relative to changes in the angle of incidence of light entering a central projection optical system is not uniform across the image plane, zoom lenses that suppress distortion using the central projection method often retain significant image blur at the periphery of the image plane even when image blur correction is performed at the center of the image plane. Changing the projection method to an equidistant projection method, which eliminates image blur differences, in order to suppress image blur at the periphery of the image plane results in significant image distortion. Therefore, such zoom lenses are often used in conjunction with imaging devices equipped with electronic distortion correction functions that correct distortion through image processing. However, excessive distortion in the central projection method can result in image degradation at the periphery of the image plane due to electronic distortion correction. Therefore, to achieve both image blur correction and suppression of image degradation at the periphery of the image plane through electronic distortion correction, it is necessary to appropriately set the distortion in the central projection method.

[0006] Furthermore, lens-shift type vibration reduction mechanisms have a higher vibration reduction sensitivity (the ratio of the amount of image blur correction to the unit movement of the vibration reduction group) at the periphery of the image plane than at the center of the image plane, so they can suppress image blur at the periphery of the image plane. Therefore, it is desirable to equip ultra-wide-angle zoom lenses with lens-shift type vibration reduction mechanisms.

[0007] SUMMARY OF THE INVENTION An object of the present invention is to provide a zoom lens that achieves both a wide angle of view and compactness, and that can maintain high optical performance even during vibration reduction, and an imaging apparatus having the same. [Means for solving the problem]

[0008] According to one aspect of the present invention, there is provided a zoom lens comprising a first lens group having negative refractive power and a rear group having positive refractive power as a whole, which are arranged in that order from the object side to the image side, the rear group including at least three lens groups, the spacing between adjacent lens groups changing during zooming, the rear group including a subgroup that moves in a direction including a component perpendicular to the optical axis during image blur correction, the first lens group including three or more negative lenses arranged in that order from the object side to the image side, at least two of the three or more negative lenses having a convex surface facing the object side and at least one having a concave surface facing the object side, the rear group including a focus group having negative refractive power that moves during focusing, wherein, when an amount of distortion at a maximum image height during focusing at infinity at the wide-angle end is defined as Dist_w, the focal length of the first lens group is defined as f1, the focal length of the final lens group in the zoom lens arranged closest to the image side is defined as fLN, and the back focus of the zoom lens at the wide-angle end is defined as skw, -20 <Dist_w<-8 -0.4 <f1 / fLN<0.7 -2.2 <f1 / skw≦-1.21 The present invention is characterized in that the following conditional expression is satisfied: [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a zoom lens that achieves both a wide angle of view and compactness, and that can maintain high optical performance even during vibration reduction, and an imaging apparatus having the same. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a cross-sectional view of a zoom lens according to a first embodiment. [Figure 2] 3A and 3B are longitudinal aberration diagrams at the wide-angle end and the telephoto end of the zoom lens of Example 1. [Figure 3] 4A and 4B are lateral aberration diagrams of the zoom lens of Example 1 at the wide-angle end and the telephoto end during image stabilization. [Figure 4] FIG. 10 is a cross-sectional view of a zoom lens according to a second embodiment. [Figure 5]10A and 10B are longitudinal aberration diagrams at the wide-angle end and the telephoto end of the zoom lens of Example 2. [Figure 6] 10A and 10B are lateral aberration diagrams of the zoom lens of Example 2 at the wide-angle end and the telephoto end during image stabilization. [Figure 7] FIG. 10 is a cross-sectional view of a zoom lens according to a third embodiment. [Figure 8] 10A and 10B are longitudinal aberration diagrams at the wide-angle end and the telephoto end of the zoom lens of Example 3. [Figure 9] 10A and 10B are lateral aberration diagrams of the zoom lens of Example 3 at the wide-angle end and the telephoto end during image stabilization. [Figure 10] FIG. 10 is a cross-sectional view of a zoom lens according to a fourth embodiment. [Figure 11] 10A and 10B are longitudinal aberration diagrams at the wide-angle end and the telephoto end of the zoom lens of Example 4. [Figure 12] 10A and 10B are lateral aberration diagrams of the zoom lens of Example 4 at the wide-angle end and the telephoto end during image stabilization. [Figure 13] FIG. 10 is a cross-sectional view of a zoom lens according to a fifth embodiment. [Figure 14] 10A and 10B are longitudinal aberration diagrams at the wide-angle end and the telephoto end of the zoom lens of Example 5. [Figure 15] 10A and 10B are lateral aberration diagrams of the zoom lens of Example 5 at the wide-angle end and the telephoto end during image stabilization. [Figure 16] FIG. 10 is a cross-sectional view of a zoom lens according to a sixth embodiment. [Figure 17] 13A and 13B are longitudinal aberration diagrams at the wide-angle end and the telephoto end of the zoom lens of Example 6. [Figure 18] 13A and 13B are lateral aberration diagrams of the zoom lens of Example 6 at the wide-angle end and the telephoto end during image stabilization. [Figure 19] FIG. 10 is a cross-sectional view of a zoom lens according to a seventh embodiment. [Figure 20] 10A and 10B are longitudinal aberration diagrams at the wide-angle end and the telephoto end of the zoom lens of Example 7. [Figure 21]13A and 13B are lateral aberration diagrams of the zoom lens of Example 7 at the wide-angle end and the telephoto end during image stabilization. [Figure 22] FIG. 1 is a schematic diagram of an imaging device. DETAILED DESCRIPTION OF THE INVENTION

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to designate the same components, and redundant explanations will be omitted.

[0012] 1, 4, 7, 10, 13, 16, and 19 are cross-sectional views of the zoom lens L0 of Examples 1 to 7 at the wide-angle end when focused at infinity. The zoom lens L0 of each Example is used in imaging devices such as digital video cameras, digital still cameras, broadcast cameras, silver halide film cameras, surveillance cameras, and vehicle-mounted cameras. The zoom lens L0 of each Example can also be used as a projection lens for projectors and the like.

[0013] In each cross-sectional view, the left side is the object side (front) and the right side is the image side (rear). The zoom lens L0 of each embodiment is configured with multiple lens groups. In this specification, a lens group refers to a group of lenses that move or remain stationary as a unit during zooming. That is, in the zoom lens L0 of each embodiment, the distance between adjacent lens groups changes during zooming. Note that a lens group may be configured with a single lens, or may be configured with multiple lenses. Furthermore, a lens group may include elements other than a lens group (for example, an aperture stop).

[0014] The zoom lens L0 of each embodiment comprises, arranged in order from the object side to the image side, a first lens unit L1 with negative refractive power and a rear lens unit LR with positive refractive power overall. The rear lens unit LR includes all lens units arranged closer to the image side than the first lens unit L1. In the zoom lens L0 of each embodiment, the distance between the first lens unit L1 and the rear lens unit LR changes during zooming.

[0015] In each cross-sectional view, Li denotes the i-th (i is a natural number) lens group included in the zoom lens L0, counting from the object side, and LN denotes the final lens group located closest to the image side.

[0016] Furthermore, SP is an aperture stop. The aperture stop SP is provided on the object side of or inside the second lens group L2. FC is a secondary stop (auxiliary stop). IP is an image plane, on which the imaging surface of a solid-state imaging element (photoelectric conversion element) such as a CCD sensor or CMOS sensor is disposed when the zoom lens L0 of each embodiment is used as the imaging optical system of a digital still camera or digital video camera. When the zoom lens L0 of each embodiment is used as the imaging optical system of a silver halide film camera, a photosensitive surface equivalent to the film surface is disposed on the image plane IP.

[0017] Furthermore, the arrows shown in the cross-sectional views indicate the direction of movement of the lens group during zooming from the wide-angle end to the telephoto end, and the direction of movement of the lens group during focusing from an object at infinity to a close-up object. In each embodiment, one entire lens group is moved during focusing, but the present invention is not limited to this. During focusing, only a portion of the lens group may be moved, or the entire zoom lens L0 may be moved. Furthermore, during focusing, multiple lenses may be moved along different trajectories.

[0018] 2, 5, 8, 11, 14, 17, and 20 are longitudinal aberration diagrams of the zoom lens L0 of Examples 1 to 7, respectively. In each longitudinal aberration diagram, (A) is a longitudinal aberration diagram at the wide-angle end, and (B) is a longitudinal aberration diagram at the telephoto end. In the spherical aberration diagram, Fno is the F-number, and shows the amount of spherical aberration for the d-line (wavelength 587.6 nm) and the g-line (wavelength 435.8 nm). In the astigmatism diagram, M shows the amount of astigmatism at the meridional image plane, and S shows the amount of astigmatism at the sagittal image plane. In the distortion diagram, the amount of distortion for the d-line is shown. In the chromatic aberration diagram, the amount of chromatic aberration at the g-line is shown. ω is the half angle of view (°).

[0019] Figures 3, 6, 9, 12, 15, 18, and 21 are lateral aberration diagrams of the zoom lens L0 of each embodiment when image stabilization is performed at 0.3°. In each lateral aberration diagram, (A) is the lateral aberration diagram at the wide-angle end, and (B) is the lateral aberration diagram at the telephoto end. The unit of each axis is mm. Y is the image height (mm) at which the lateral aberration diagrams were evaluated.

[0020] Next, the characteristic configuration of the zoom lens L0 of each embodiment will be described.

[0021] The zoom lens L0 in each embodiment is a so-called negative lead type zoom lens in which the refractive power of the first lens unit L1 is negative. Negative lead type zoom lenses are known as having a configuration that is effective for widening the angle of view of zoom lenses.

[0022] The rear group LR includes a subgroup (image stabilization group) LIS that moves in a direction including a component perpendicular to the optical axis during image blur correction. This reduces the height of off-axial light rays incident on the subgroup LIS, making it possible to suppress deterioration of optical performance during image stabilization. In this specification, a subgroup refers to a group of lenses whose structural length (the distance on the optical axis from the lens surface closest to the object to the lens surface closest to the image) remains constant during zooming. The subgroup may be a single lens group or a part of a single lens group.

[0023] The first lens group L1 includes three or more negative lenses arranged in order from the object side to the image side, which makes it possible to ensure a sufficiently wide angle of view (for example, a field angle of 100° or more at the wide-angle end).

[0024] The zoom lens L0 of each embodiment satisfies the following conditional expressions (1) and (2).

[0025] -20 <Dist_w<-8 (1) -0.4 <f1 / fLN<0.7 (2) Here, Dist_w is the amount of distortion at the maximum image height when focusing at infinity at the wide-angle end, f1 is the focal length of the first lens unit L1, and fLN is the focal length of the final lens unit LN.

[0026] Conditional formula (1) defines the amount of distortion at the maximum image height when focusing at infinity at the wide-angle end. The maximum image height is the distance from the optical axis to the image point that is farthest from the optical axis among the image points that can be photographed. If the amount of distortion becomes too large, exceeding the upper limit of conditional formula (1), the amount of distortion in the equidistant projection method will be too large, resulting in significant degradation of image quality around the periphery of the imaging plane during image blur correction. Furthermore, even during lens shift image stabilization, the amount of image blur correction around the periphery of the imaging plane will be insufficient. If the amount of distortion becomes too small, falling below the lower limit of conditional formula (1), it will be difficult to suppress degradation of image quality around the periphery of the imaging plane during electronic distortion correction.

[0027] Here, when the ideal image height in the central projection method is y and the real image height is yp, the distortion amount Dist_w [%] of an arbitrary image height at the wide-angle end is defined by the following equation.

[0028] Dist_w[%]=((yp-y) / y)×100 The ideal image height y in the central projection method is defined by the following equation, where f is the focal length of the zoom lens L0 and θi is the half angle of view of the actual light ray at an arbitrary image height.

[0029] y=f tanθi Conditional expression (2) defines the ratio between the focal length of the first lens group L1 and the focal length of the final lens group LN. Satisfying conditional expression (2) enables both compactness and high image quality. If the upper limit of conditional expression (2) is exceeded and the negative refractive power of the final lens group LN becomes too strong, it becomes difficult to achieve a retrofocus refractive power arrangement, making it difficult to widen the angle of view while maintaining back focus at the wide-angle end. If the lower limit of conditional expression (2) is exceeded and the positive refractive power of the final lens group LN becomes too strong, the retrofocus refractive power arrangement becomes too strong, increasing the asymmetry of the refractive power arrangement of the zoom lens L0 and making it difficult to correct distortion at the wide-angle end. Furthermore, it becomes difficult to shorten the overall lens length of the zoom lens L0 at the wide-angle end (the distance on the optical axis from the lens surface closest to the object to the image plane IP).

[0030] By having the above-described configuration, the zoom lens L0 of each embodiment can achieve both a wide angle of view and compactness, and can also maintain high optical performance even during vibration reduction.

[0031] It is preferable that the numerical ranges of the conditional expressions (1) and (2) be set to the numerical ranges of the following conditional expressions (1a) and (2a).

[0032] -19 <Dist_w<-9 (1a) -0.37 <f1 / fLN<0.60 (2a) It is more preferable that the numerical ranges of the conditional expressions (1) and (2) be set to the numerical ranges of the following conditional expressions (1b) and (2b).

[0033] -18 <Dist_w<-10 (1b) -0.34 <f1 / fLN<0.50 (2b) Next, conditions that the zoom lens L0 of each embodiment should preferably satisfy will be described. The zoom lens L0 of each embodiment should preferably satisfy one or more of the following conditional expressions (3) to (12).

[0034] 1.0<|fLIS / ft|<4.0 (3) 0.00≦dIS / dt<0.25 (4) 0.1 <dLIS / dR<10.0 (5) 30<νLIS<70 (6) -1.0<(r1+r2) / (r1-r2)<0.6 (7) -2.2 <f1 / skw<-0.9 (8) -2.2 <f1 / fw<-1.0 (9) -0.5 <fw / fLN<0.3 (10) -1.5 <Ymax_w / f1<-0.4 (11) Here, fLIS is the focal length of the subgroup LN. ft is the focal length of the zoom lens L0 at the telephoto end. dIS is the axial distance from the lens surface of the rear group LR closest to the object to the lens surface of the subgroup LIS closest to the object at the telephoto end. dt is the overall lens length of the zoom lens L0 at the telephoto end. dLIS is the axial distance from the lens surface of the subgroup LIS closest to the object to the lens surface closest to the image. dR is the axial distance from the lens surface of the subgroup LIS closest to the image at the wide-angle end to the lens surface closest to the object of the lens group adjacent to the subgroup LIS on the image side. νLIS is the Abbe number of the lens with the shortest focal length included in the subgroup LIS. r1 is the radius of curvature of the lens surface of the subgroup LIS closest to the object. r2 is the radius of curvature of the lens surface of the subgroup LIS closest to the image. skw is the back focus of the zoom lens L0 at the wide-angle end. fw is the focal length of the zoom lens L0 at the wide-angle end, and Ymax_w is the maximum image height at the wide-angle end.

[0035] Conditional expression (3) defines the refractive power of the subgroup LIS. Satisfying conditional expression (3) makes it possible to both reduce the lens outer diameter and suppress aberration fluctuations during image stabilization. If the upper limit of conditional expression (3) is exceeded and the refractive power of the subgroup LIS becomes too weak, the amount of movement of the subgroup LIS during image stabilization becomes too large, making it difficult to reduce the lens outer diameter. If the lower limit of conditional expression (3) is exceeded and the refractive power of the subgroup LIS becomes too strong, making it difficult to suppress fluctuations in coma and field curvature during image stabilization.

[0036] Conditional expression (4) defines the axial distance from the lens surface of the rear group LR closest to the object to the lens surface of the partial group LIS closest to the object at the telephoto end. If the upper limit of conditional expression (4) is exceeded and the distance from the lens surface of the rear group LR closest to the object to the lens surface of the partial group LIS closest to the object becomes too long, it becomes difficult to suppress fluctuations in coma during image stabilization. If the lower limit of conditional expression (4) is exceeded and the distance from the lens surface of the rear group LR closest to the object to the lens surface of the partial group LIS closest to the object becomes too short, it becomes difficult to appropriately position the drive unit that drives the partial group LIS and the drive unit that drives the aperture stop SP.

[0037] Conditional formula (5) defines the ratio between the thickness of the subunit LIS and the spacing between the subsequent unit LR. If the thickness of the subunit LIS exceeds the upper limit of conditional formula (5) and becomes too thick, the subunit LIS becomes heavy, the drive unit becomes large, and it becomes difficult to reduce the lens outer diameter. If the thickness of the subunit LIS falls below the lower limit of conditional formula (5) and becomes too thin, it becomes difficult to appropriately set the radius of curvature of the subunit LIS, and it becomes difficult to suppress fluctuations in coma and field curvature during image stabilization.

[0038] Conditional expression (6) defines the Abbe number of the lens with the shortest focal length included in the subgroup LIS. If the subgroup LIS has positive refractive power, it defines the Abbe number of the positive lens, and if it has negative refractive power, it defines the Abbe number of the negative lens. If the upper limit of conditional expression (6) is exceeded and the Abbe number becomes large, the refractive index becomes small, making it difficult to suppress fluctuations in coma aberration during image stabilization. If the Abbe number becomes small and falls below the lower limit of conditional expression (6), it becomes difficult to suppress fluctuations in lateral chromatic aberration during image stabilization.

[0039] Conditional expression (7) defines the shape factor of the subgroup LIS. If the upper limit of conditional expression (7) is exceeded and the subgroup LIS assumes a meniscus shape with its concave surface facing the image side, it becomes difficult to suppress fluctuations in field curvature during image vibration reduction. If the lower limit of conditional expression (7) is not reached and the subgroup LIS assumes a meniscus shape with its concave surface facing the object side, it becomes difficult to suppress fluctuations in coma during image vibration reduction.

[0040] Conditional expression (8) defines the ratio of the back focal length of the zoom lens L0 to the focal length of the first lens unit L1 at the wide-angle end. If the upper limit of conditional expression (8) is exceeded and the negative refractive power of the first lens unit L1 becomes too strong, the asymmetry of the refractive power distribution of the zoom lens L0 becomes stronger, making it difficult to correct distortion at the wide-angle end. If the lower limit of conditional expression (8) is exceeded and the negative refractive power of the first lens unit L1 becomes too weak, it becomes difficult to achieve a wide angle of view exceeding 100° at the wide-angle end. In addition, the front lens diameter becomes large, resulting in an increase in the lens outer diameter.

[0041] Conditional expression (9) defines the focal length of the first lens unit L1. If the upper limit of conditional expression (9) is exceeded and the negative refractive power of the first lens unit L1 becomes too strong, the asymmetry of the refractive power arrangement of the zoom lens L0 becomes stronger, making it difficult to correct distortion at the wide-angle end. If the lower limit of conditional expression (9) is exceeded and the refractive power of the first lens unit L1 becomes too weak, it becomes difficult to achieve a wide angle of view exceeding 100° at the wide-angle end. Furthermore, the front lens diameter becomes large, resulting in an increase in the lens outer diameter.

[0042] Conditional expression (10) defines the focal length of the final lens unit LN. If the upper limit of conditional expression (10) is exceeded and the positive refractive power of the final lens unit LN becomes too strong, the retrofocus refractive power arrangement becomes strong, which increases the asymmetry of the refractive power arrangement of the zoom lens L0 and makes it difficult to correct distortion at the wide-angle end. It also makes it difficult to shorten the overall lens length at the wide-angle end. If the lower limit of conditional expression (10) is exceeded and the negative refractive power of the final lens unit LN becomes too strong, it makes it difficult to achieve a retrofocus refractive power arrangement, making it difficult to widen the angle of view while ensuring the back focus at the wide-angle end.

[0043] Conditional expression (11) defines the maximum image height that can be captured at the wide-angle end. Satisfying conditional expression (11) allows the zoom lens L0 to be made smaller and lighter. If the upper limit is exceeded and the maximum image height becomes too large, a wider range of light rays than the desired angle of view will be focused on the imaging plane, which will result in excessively large mechanical mechanisms and optical systems, making it difficult to make the zoom lens L0 smaller and lighter. If the lower limit is exceeded and the maximum image height becomes too small, the angle of view will be narrower than the desired angle of view, which is undesirable.

[0044] It is preferable that the numerical ranges of the conditional expressions (3) to (11) be the numerical ranges of the following conditional expressions (3a) to (11a).

[0045] 1.1<|fLIS / ft|<3.5 (3a) 0.00≦dIS / dt<0.20 (4a) 0.2 <dLIS / dR<8.0 (5a) 32 <vLIS<68 (6a) -0.8<(r1+r2) / (r1-r2)<0.5 (7a) -2.1 <f1 / skw<-1.0 (8a) -2.1 <f1 / fw<-1.1 (9a) -0.40 <fw / fLN<0.25 (10a) -1.4 <Ymax_w / f1<-0.5 (11a) It is more preferable that the numerical ranges of the conditional expressions (3) to (11) be the numerical ranges of the following conditional expressions (3b) to (11b).

[0046] 1.2<|fLIS / ft|<3.0 (3b) 0.00≦dIS / dt<0.15 (4b) 0.3 <dLIS / dR<6.0 (5b) 34 <vLIS<66 (6b) -0.7<(r1+r2) / (r1-r2)<0.4 (7b) -2.0 <f1 / skw<-1.1 (8b) -2.0 <f1 / fw<-1.2 (9b) -0.30 <fw / fLN<0.20 (10b) -1.3 <Ymax_w / f1<-0.6 (11b) Next, the configuration that is preferably satisfied in the zoom lens L0 of each embodiment will be described.

[0047] The subgroup LIS preferably includes a positive lens and a negative lens, which makes it possible to effectively suppress fluctuations in chromatic aberration of magnification and curvature of field during image stabilization.

[0048] The rear group LR is preferably arranged on the image side of the subgroup LIS and includes two or more lens groups whose spacing changes during zooming, which makes it possible to achieve a sufficient zoom ratio (for example, 2x) while ensuring a sufficiently wide angle of view (for example, an angle of view of 100° or more at the wide-angle end).

[0049] The rear unit LR is preferably disposed on the image side of the subunit LIS and includes a focus unit that moves during focusing. By disposing the vibration reduction unit near the aperture stop and the focus unit near the image plane, it is possible to suppress aberration fluctuations during vibration reduction and focusing at the same time.

[0050] At the wide-angle end, it is preferable that the distance between the first lens group L1 and the rear group LR is the largest among the distances between the lens groups included in the zoom lens L0. This configuration allows for a large change in the distance between the first lens group L1 and the rear group LR during zooming, making it easier to ensure a desired zoom ratio.

[0051] The first lens unit L1 preferably includes a positive lens. With this configuration, chromatic aberration can be corrected within the first lens unit L1, and fluctuations in chromatic aberration during zooming can be suppressed.

[0052] The zoom lens L0 preferably has a storage unit that stores distortion correction data for correcting distortion. With this configuration, the zoom lens L0 can be made smaller.

[0053] Next, the zoom lens L0 of each embodiment will be described in detail.

[0054] The zoom lens L0 of Example 1 comprises, arranged in order from the object side to the image side, a first lens group L1 with negative refractive power and a rear group LR with negative refractive power overall. The rear group LR comprises, arranged in order from the object side to the image side, a second lens group L2 with positive refractive power, a third lens group L3 with negative refractive power, a fourth lens group L4 with negative refractive power, and a fifth lens group L5 with positive refractive power. A portion of the second lens group L2 is a partial group LIS. The third lens group L3 is a focusing group. The fifth lens group L5 is the final lens group LN. During zooming from the wide-angle end to the telephoto end, the first lens group L1 moves toward the image side and then moves toward the object side. The second lens group L2 moves toward the object side while decreasing the distance between it and the first lens group L1. The third lens group L3 moves toward the object side while increasing the distance between it and the second lens group L2. The fourth lens group L4 moves toward the object side while decreasing the distance between it and the third lens group L3. The fifth lens group L5 moves toward the object side while increasing the distance between it and the fourth lens group L4, and then moves toward the image side. When focusing from an object at infinity to a close object, the third lens group L3 moves toward the image side.

[0055] The zoom lens L0 of Example 2 comprises, arranged in order from the object side to the image side, a first lens unit L1 with negative refractive power and a rear lens unit LR with negative refractive power overall. The rear lens unit LR comprises, arranged in order from the object side to the image side, a second lens unit L2 with positive refractive power, a third lens unit L3 with negative refractive power, a fourth lens unit L4 with positive refractive power, a fifth lens unit L5 with negative refractive power, and a sixth lens unit L6 with positive refractive power. The third lens unit L3 is a partial lens unit LIS. The fifth lens unit L5 is a focusing lens unit. The sixth lens unit L6 is the final lens unit LN. During zooming from the wide-angle end to the telephoto end, the first lens unit L1 moves toward the image side. The second lens unit L2 moves toward the object side while decreasing the distance between it and the first lens unit L1. The third lens unit L3 moves toward the object side while decreasing the distance between it and the second lens unit L2. The fourth lens group L4 moves toward the object side while decreasing the distance between it and the third lens group L3. The fifth lens group L5 moves toward the object side while increasing the distance between it and the fourth lens group L4. The sixth lens group L6 moves toward the object side while increasing the distance between it and the fifth lens group L5. Furthermore, when focusing from an object at infinity to a close object, the fifth lens group L5 moves toward the image side.

[0056] The zoom lens L0 of Example 3 comprises, arranged in order from the object side to the image side, a first lens unit L1 with negative refractive power and a rear lens unit LR with negative refractive power overall. The rear lens unit LR comprises, arranged in order from the object side to the image side, a second lens unit L2 with positive refractive power, a third lens unit L3 with positive refractive power, a fourth lens unit L4 with negative refractive power, a fifth lens unit L5 with negative refractive power, and a sixth lens unit L6 with positive refractive power. A portion of the second lens unit L2 is a partial lens unit LIS. The fourth lens unit L4 is a focusing unit. The sixth lens unit L6 is the final lens unit LN. During zooming from the wide-angle end to the telephoto end, the first lens unit L1 moves toward the image side and then toward the object side. The second lens unit L2 moves toward the object side while decreasing the distance between it and the first lens unit L1. The third lens unit L3 moves toward the object side while decreasing the distance between it and the second lens unit L2. The fourth lens group L4 moves toward the object while increasing the distance between it and the third lens group L3. The fifth lens group L5 moves toward the object while decreasing the distance between it and the fourth lens group L4. The sixth lens group L6 remains stationary. Furthermore, during focusing from an object at infinity to a close object, the fourth lens group L4 moves toward the image.

[0057] The zoom lens L0 of Example 4 comprises, arranged in order from the object side to the image side, a first lens unit L1 with negative refractive power and a rear lens unit LR with negative refractive power overall. The rear lens unit LR comprises, arranged in order from the object side to the image side, a second lens unit L2 with positive refractive power, a third lens unit L3 with negative refractive power, a fourth lens unit L4 with positive refractive power, a fifth lens unit L5 with negative refractive power, a sixth lens unit L6 with negative refractive power, and a seventh lens unit L7 with positive refractive power. The third lens unit L3 is a partial lens unit LIS. The fifth lens unit L5 is a focusing lens unit. The seventh lens unit L7 is the final lens unit LN. During zooming from the wide-angle end to the telephoto end, the first lens unit L1 moves toward the image side and then toward the object side. The second lens unit L2 moves toward the object side while decreasing the distance between it and the first lens unit L1. The third lens unit L3 moves toward the object side while increasing the distance between it and the second lens unit L2. The fourth lens group L4 moves toward the object side while decreasing the distance between it and the third lens group L3. The fifth lens group L5 moves toward the object side while increasing the distance between it and the fourth lens group L4. The sixth lens group L6 moves toward the object side while decreasing the distance between it and the fifth lens group L5. The seventh lens group L7 remains stationary. Furthermore, when focusing from an object at infinity to a close object, the fifth lens group L5 moves toward the image side.

[0058] The zoom lens L0 of Example 5 comprises, arranged in order from the object side to the image side, a first lens unit L1 with negative refractive power and a rear lens unit LR with negative refractive power as a whole. The rear lens unit LR comprises, arranged in order from the object side to the image side, a second lens unit L2 with positive refractive power, a third lens unit L3 with negative refractive power, a fourth lens unit L4 with negative refractive power, and a fifth lens unit L5 with positive refractive power. A portion of the second lens unit L2 is a partial lens unit LIS. The third lens unit L3 is a focusing unit. The fifth lens unit L5 is the final lens unit LN. During zooming from the wide-angle end to the telephoto end, the first lens unit L1 moves toward the image side and then moves toward the object side. The second lens unit L2 moves toward the object side while decreasing the distance between it and the first lens unit L1. The third lens unit L3 moves toward the object side while increasing the distance between it and the second lens unit L2. The fourth lens unit L4 moves toward the object side while decreasing the distance between it and the third lens unit L3. The fifth lens unit L5 moves toward the image side while increasing the distance between it and the fourth lens unit L4. When focusing from an object at infinity to an object at a close distance, the third lens unit L3 moves toward the image side.

[0059] The zoom lens L0 of Example 6 comprises, arranged in order from the object side to the image side, a first lens unit L1 with negative refractive power and a rear lens unit LR with negative refractive power overall. The rear lens unit LR comprises, arranged in order from the object side to the image side, a second lens unit L2 with positive refractive power, a third lens unit L3 with positive refractive power, a fourth lens unit L4 with negative refractive power, a fifth lens unit L5 with negative refractive power, and a sixth lens unit L6 with positive refractive power. A portion of the second lens unit L2 is a partial lens unit LIS. The fourth lens unit L4 is a focusing unit. The sixth lens unit L6 is the final lens unit LN. During zooming from the wide-angle end to the telephoto end, the first lens unit L1 moves toward the image side and then toward the object side. The second lens unit L2 moves toward the object side while decreasing the distance between it and the first lens unit L1. The third lens unit L3 moves toward the object side while decreasing the distance between it and the second lens unit L2. The fourth lens group L4 moves toward the object while increasing the distance between it and the third lens group L3. The fifth lens group L5 moves toward the object while decreasing the distance between it and the fourth lens group L4. The sixth lens group L6 remains stationary. Furthermore, during focusing from an object at infinity to a close object, the fourth lens group L4 moves toward the image.

[0060] The zoom lens of Example 7 comprises, arranged in order from the object side to the image side, a first lens unit L1 with negative refractive power and a rear lens unit LR with negative refractive power as a whole. The rear lens unit LR comprises, arranged in order from the object side to the image side, a second lens unit L2 with positive refractive power, a third lens unit L3 with negative refractive power, and a fourth lens unit L4 with negative refractive power. A portion of the second lens unit L2 is a partial lens unit LIS. The third lens unit L3 is a focusing unit. The fourth lens unit L4 is the final lens unit LN. During zooming from the wide-angle end to the telephoto end, the first lens unit L1 moves toward the image side and then moves toward the object side. The second lens unit L2 moves toward the object side while decreasing the distance between it and the first lens unit L1. The third lens unit L3 moves toward the object side while increasing the distance between it and the second lens unit L2. The fourth lens unit L4 moves toward the object side while decreasing the distance between it and the third lens unit L3. Furthermore, during focusing from an object at infinity to a close object, the third lens unit L3 moves toward the image side.

[0061] Numerical Examples 1 to 7 corresponding to Examples 1 to 7, respectively, are shown below.

[0062] 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. Furthermore, nd represents the refractive index of each optical element with respect to the d-line, and vd represents the Abbe number of the optical element. Note that the Abbe number vd of a certain material is given by the following when the refractive indices at the Fraunhofer lines d-line (587.6 nm), F-line (486.1 nm), C-line (656.3 nm), and g-line (wavelength 435.8 nm) are Nd, NF, and NC, respectively: νd=(Nd-1) / (NF-NC) It is expressed as:

[0063] In each numerical example, d, focal length (mm), F-number, and half angle of view (degrees) are all values ​​when the zoom lens L0 of each example is focused on an object at infinity. "Back focus" is the distance on the optical axis from the final lens surface (the lens surface closest to the image) to the paraxial image plane, expressed as an air-equivalent length. "Total lens length" is the distance on the optical axis from the forefront lens surface (the lens surface closest to the object) of the zoom lens L0 to the final surface plus the back focus. "Lens group" is not limited to cases where it is composed of multiple lenses, but also includes cases where it is composed of a single lens.

[0064] If the optical surface is aspherical, an asterisk (*) is added to the right of the surface number. The aspherical shape is expressed as follows: X is the displacement from the vertex of the surface in the optical axis direction, h is the height from the optical axis in the direction perpendicular to the optical axis, R is the paraxial radius of curvature, K is the conic constant, and A4, A6, A8, A10, and A12 are the aspherical coefficients of each order. X=(h 2 / R) / [1+{1-(1+K)(h / R) 2} 1 / 2 +A4×h 4 +A6×h 6 +A8×h 8 +A10×h 10 +A12×h 12 In addition, "e±XX" in each aspherical coefficient is "×10± XX " means. [Numerical Example 1] Unit: mm Surface Data Surface number rd nd νd Effective diameter 1 51.172 2.10 1.76385 48.5 60.00 2 22.116 5.35 41.92 3* 43.332 2.60 1.58313 59.4 41.25 4* 20.040 7.86 35.56 5 46.620 1.30 1.49700 81.5 35.20 6 20.811 8.63 30.19 7 -72.638 1.20 1.43875 94.7 29.72 8 28.416 3.02 27.38 9 31.708 4.25 1.72047 34.7 27.20 10 299.251 (variable) 26.57 11 (Aperture) ∞ 0.50 15.47 12 20.518 0.90 1.90043 37.4 16.09 13 14.081 5.42 1.51633 64.1 15.68 14 -41.681 1.39 15.71 15 -45.264 0.70 1.79952 42.2 15.44 16 17.644 2.65 2.00069 25.5 15.61 17 53.947 1.00 15.54 18 (auxiliary aperture) ∞ 1.25 15.63 19 18.253 0.80 1.95375 32.3 16.23 20 12.998 7.21 1.49700 81.5 15.66 21 -21.295 0.80 1.72916 54.7 15.48 22 45.323 0.15 15.64 23 19.970 5.19 1.43875 94.7 17.39 24 -54.434 0.15 18.22 25* 29.740 4.95 1.49700 81.5 18.94 26* -37.767 (variable) 19.14 27 50.182 0.75 1.72916 54.7 18.86 28 26.486 (variable) 18.54 29 -18.815 1.50 1.85400 40.4 19.72 30* -37.763 (variable) 21.83 31 -568.191 6.05 1.49700 81.5 36.04 32 -38.524 (variable) 37.01 Image plane ∞ Aspheric data 3rd page K = 0.00000e+000 A 4= 7.52315e-005 A 6=-2.85004e-007 A 8= 8.08696e-010 A10=-1.62370e-012 A12= 2.19074e-015 A14=-1.39196e-018 Side 4 K =-7.00172e-001 A 4= 8.26202e-005 A 6=-2.36130e-007 A 8=-1.14795e-010 A10= 2.29302e-012 A12=-5.42273e-015 A14= 3.67687e-018 Page 25 K = 0.00000e+000 A 4=-4.19009e-005 A 6=-1.88923e-007 A 8= 2.54663e-009 A10=-2.45675e-011 A12= 1.85699e-013 Page 26 K = 0.00000e+000 A 4=-3.92596e-006 A 6=-2.00765e-007 A 8= 4.34769e-009 A10=-4.17031e-011 A12= 2.70334e-013 Page 30 K = 0.00000e+000 A 4= 3.55737e-005 A 6= 8.04633e-008 A 8=-5.06048e-011 A10=-1.92129e-012 A12= 1.00728e-014 Various data Zoom ratio 2.06 Wide-angle Mid-range Telephoto Focal length 11.33 17.56 23.30 F-number 4.08 4.08 4.12 Half angle of view (degrees) 59.63 50.70 42.88 Image height 19.33 21.64 21.64 Lens total length 135.40 127.26 130.90 BF 13.63 16.01 14.26 d10 31.08 13.08 6.86 d26 1.40 2.76 3.05 d28 10.82 9.46 9.16 d30 0.80 8.28 19.88 d32 13.63 16.01 14.26 Zoom lens group data Group starting plane focal length 1 1 -19.57 2 11 24.55 3 27 -77.97 4 29 -45.57 5 31 82.84 [Numerical Example 2] Unit: mm Surface Data Surface number rd nd νd Effective diameter 1 40.613 1.70 1.76385 48.5 51.00 2 19.325 5.42 36.63 3* 31.250 2.30 1.58313 59.4 35.85 4* 17.371 9.00 30.81 5 169.823 1.30 1.49700 81.5 30.26 6 27.182 6.81 26.85 7 -204.838 1.20 1.43875 94.7 24.92 8 26.012 3.14 1.72047 34.7 23.15 9 72.443 (variable) 22.50 10 31.749 2.47 1.54814 45.8 17.19 11 ∞ 0.50 17.35 12 (Aperture) ∞ 0.50 17.44 13 31.532 0.90 1.81554 44.4 17.78 14 14.990 5.80 1.51823 58.9 17.39 15 -58.790 (variable) 17.59 16 -47.567 0.70 1.72047 34.7 17.56 17 45.836 1.70 2.00069 25.5 17.89 18 176.965 2.00 17.96 19 (auxiliary aperture) ∞ (variable) 18.37 20 36.570 0.90 1.83481 42.7 19.05 21 17.537 5.37 1.43875 94.7 19.41 22 169.591 0.20 21.16 23 29.382 8.39 1.43875 94.7 23.63 24 -39.782 0.20 24.89 25* 59.282 9.17 1.49700 81.5 25.50 26* -31.136 (variable) 25.39 27 -91.656 1.50 2.00069 25.5 23.92 28 -57.835 0.75 1.72047 34.7 23.84 29 43.358 (variable) 23.25 30* -27.441 1.60 1.85400 40.4 23.53 31* -60.934 0.20 25.65 32 178.490 5.04 1.49700 81.5 27.62 33 -37.343 (variable) 28.73 Image plane ∞ Aspheric data 3rd page K = 0.00000e+000 A 4= 6.49432e-005 A 6=-2.09847e-007 A 8= 3.22034e-010 A10=-3.56124e-014 A12=-2.65892e-016 A14=-2.11568e-019 Side 4 K =-5.81434e-001 A 4= 7.42938e-005 A 6=-8.59222e-008 A 8=-1.56177e-009 A10= 9.19947e-012 A12=-2.30787e-014 A14= 1.96904e-017 Page 25 K = 0.00000e+000 A 4=-1.13378e-005 A 6=-4.96476e-009 A 8= 3.96013e-011 A10= 5.02938e-013 A12= 1.73732e-015 Page 26 K = 0.00000e+000 A 4=-6.09923e-006 A 6= 1.18821e-008 A 8= 4.84539e-011 A10=-6.24432e-014 A12= 4.33687e-015 Page 30 K = 0.00000e+000 A 4=-6.59258e-005 A 6= 7.46300e-007 A 8=-5.93573e-009 A10= 2.94143e-011 A12=-6.27604e-014 Page 31 K = 0.00000e+000 A 4=-2.90274e-005 A 6= 6.29498e-007 A 8=-3.79841e-009 A10= 1.47494e-011 A12=-2.52922e-014 Various data Zoom ratio 1.89 Wide-angle Mid-range Telephoto Focal length 12.36 17.28 23.30 F-number 2.91 2.91 2.91 Half angle of view (degrees) 57.41 51.25 42.88 Image height 19.33 21.64 21.64 Lens total length 130.51 122.33 119.64 BF 13.43 18.88 24.55 d 9 22.59 9.36 1.00 d15 1.81 1.40 1.40 d19 5.47 3.28 1.30 d26 1.40 3.02 5.40 d29 7.03 7.60 7.20 d33 13.43 18.88 24.55 Zoom lens group data Group starting plane focal length 1 1 -16.25 2 10 32.38 3 16 -67.90 4 20 23.86 5 27 -43.80 6 30 2124.22 [Numerical Example 3] Unit: mm Surface Data Surface number rd nd νd Effective diameter 1 53.599 1.40 1.77250 49.6 43.82 2 18.113 5.22 32.21 3* 22.075 2.20 1.58313 59.4 31.65 4* 10.628 10.87 26.46 5 -44.745 1.00 1.49700 81.5 26.19 6 57.018 0.20 25.97 7 34.464 5.00 1.83400 37.2 26.18 8 -232.206 (variable) 25.60 9 (Aperture) ∞ 0.30 18.03 10 28.190 0.90 1.95375 32.3 18.71 11 16.928 4.39 1.63980 34.5 18.37 12 92.174 0.15 18.46 13 22.781 0.90 1.91082 35.3 18.81 14 13.865 7.08 1.51633 64.1 18.09 15 -77.716 1.33 18.16 16 -101.166 0.70 1.72047 34.7 18.03 17 22.540 2.37 2.00069 25.5 18.09 18 52.661 (variable) 17.96 19 27.758 0.90 1.80400 46.5 18.26 20 13.290 6.78 1.49700 81.5 17.64 21 -85.129 0.20 17.86 22* 31.208 6.99 1.49700 81.5 19.27 23* -21.124 (variable) 20.01 24 97.737 0.75 1.80400 46.5 19.32 25 22.020 (variable) 18.89 26* -83.892 1.60 1.85400 40.4 21.10 27* 1997.530 (variable) 22.21 28 -426.907 5.12 1.48749 70.2 38.12 29 -49.575 14.99 38.85 Image plane ∞ Aspheric data 3rd page K = 0.00000e+000 A 4=-4.03233e-005 A 6= 2.84310e-007 A 8=-1.85419e-009 A10= 6.48125e-012 A12=-1.22378e-014 A14= 9.28892e-018 Side 4 K =-5.60601e-001 A 4=-6.16452e-005 A 6= 2.38219e-007 A 8=-1.71089e-009 A10=-6.46493e-012 A12= 6.50194e-014 A14=-1.76965e-016 Page 22 K = 0.00000e+000 A 4=-1.67837e-005 A 6=-3.64843e-008 A 8= 1.07618e-009 A10=-1.24350e-011 A12= 7.09601e-014 Page 23 K = 0.00000e+000 A 4= 1.93177e-005 A 6=-1.27575e-007 A 8= 6.12378e-010 A10=-8.15372e-012 A12= 4.33482e-014 Page 26 K = 0.00000e+000 A 4= 2.55101e-005 A 6=-2.64846e-007 A 8=-4.54960e-010 A10= 8.83199e-012 A12=-3.33076e-014 Page 27 K = 0.00000e+000 A 4= 3.69079e-005 A 6=-2.56285e-007 A 8= 4.52183e-010 A10= 1.47250e-012 A12=-6.14678e-015 Various data Zoom ratio 2.35 Wide-angle Mid-range Telephoto Focal length 14.42 24.42 33.95 F-number 4.08 4.08 4.12 Half angle of view (degrees) 53.26 41.34 32.50 Image height 19.32 21.64 21.64 Lens length 125.87 118.34 125.87 BF 14.99 14.99 14.99 d 8 27.76 8.00 2.38 d18 4.14 2.93 1.30 d23 1.40 2.29 1.88 d25 7.46 6.57 6.97 d27 3.78 17.21 32.00 Zoom lens group data Group starting plane focal length 1 1 -22.94 2 9 62.86 3 19 21.50 4 24 -35.51 5 26 -94.24 6 28 114.54 [Numerical Example 4] Unit: mm Surface Data Surface number rd nd νd Effective diameter 1 69.215 1.70 1.76385 48.5 50.85 2 21.428 5.17 37.62 3* 31.249 2.30 1.58313 59.4 37.18 4* 15.909 12.89 32.33 5 -42.876 1.00 1.43875 94.7 31.99 6 106.477 0.20 31.70 7 45.553 4.49 1.83400 37.2 31.79 8 -634.660 (variable) 31.36 9 (Aperture) ∞ (Variable) 23.60 10 52.261 2.46 1.72916 54.7 26.10 11 263.265 0.15 26.10 12 31.910 0.90 1.95375 32.3 26.30 13 17.077 8.89 1.58267 46.4 24.93 14 -117.291 (variable) 24.86 15 -91.733 0.70 1.72047 34.7 24.27 16 27.559 2.96 2.00069 25.5 24.34 17 64.329 2.00 24.19 18 (auxiliary aperture) ∞ (variable) 24.31 19 32.406 0.90 1.83481 42.7 24.83 20 17.852 8.12 1.43875 94.7 23.93 21 -123.183 0.20 24.22 22* 33.004 9.54 1.49700 81.5 26.54 23* -23.827 (variable) 27.20 24 4131.745 2.01 2.00069 25.5 25.45 25 -88.248 0.75 1.72047 34.7 25.27 26 31.864 (variable) 24.27 27* -166.689 1.60 1.85400 40.4 24.90 28* 82.150 (variable) 25.59 29 595.501 5.92 1.49700 81.5 39.14 30 -50.768 15.11 39.80 Image plane ∞ Aspheric data 3rd page K = 0.00000e+000 A 4= 1.41959e-005 A 6=-7.81904e-008 A 8= 3.46364e-010 A10=-1.01509e-012 A12= 1.45953e-015 A14=-7.30050e-019 Side 4 K =-6.36442e-001 A 4= 1.55368e-005 A 6=-1.12080e-007 A 8= 5.29838e-010 A10=-1.99889e-012 A12= 2.59583e-015 A14=-2.64013e-019 Page 22 K = 0.00000e+000 A 4=-6.99798e-006 A 6=-1.13680e-008 A 8= 1.53877e-011 A10=-1.10382e-013 A12=-4.97644e-016 Page 23 K = 0.00000e+000 A 4= 2.44559e-005 A 6=-8.82874e-008 A 8= 1.95669e-010 A10=-1.85265e-013 A12=-1.18827e-015 Page 27 K = 0.00000e+000 A 4= 5.05507e-005 A 6=-7.34842e-007 A 8= 4.77038e-009 A10=-1.90408e-011 A12= 3.62227e-014 Page 28 K = 0.00000e+000 A 4= 5.77402e-005 A 6=-6.55664e-007 A 8= 4.27445e-009 A10=-1.57305e-011 A12= 2.69924e-014 Various data Zoom ratio 2.20 Wide-angle Mid-range Telephoto Focal length 15.45 25.03 33.95 F-number 2.91 2.91 2.91 Half angle of view (degrees) 51.37 40.70 32.51 Image height 19.33 21.64 21.64 Lens length 149.62 134.58 135.96 BF 15.11 15.11 15.11 d 8 38.59 12.29 2.42 d 9 0.50 3.59 4.63 d14 1.64 3.26 3.73 d18 8.30 3.20 1.30 d23 1.40 1.44 2.33 d26 6.53 8.68 6.05 d28 2.71 12.16 25.54 Zoom lens group data Group starting plane focal length 1 1 -28.99 2 9 ∞ 3 10 41.93 4 15 -75.73 5 19 25.63 6 24 -52.21 7 27 -64.25 8 29 94.41 [Numerical Example 5] Unit: mm Surface Data Surface number rd nd νd Effective diameter 1 48.538 2.10 1.76385 48.5 60.00 2 21.514 6.80 41.40 3* 41.518 2.60 1.58313 59.4 40.59 4* 19.615 11.68 34.73 5 -272.695 1.30 1.49700 81.5 34.04 6 37.773 3.45 30.53 7 -13097.059 1.20 1.43875 94.7 30.39 8 26.973 3.42 28.26 9 32.744 4.40 1.72047 34.7 28.06 10 377.895 (variable) 27.42 11 (Aperture) ∞ 0.50 14.70 12 22.168 0.90 1.88300 40.8 15.20 13 13.223 6.36 1.51633 64.1 14.83 14 -23.367 1.60 15.03 15 -20.976 0.70 1.83481 42.7 14.66 16 23.672 2.79 2.00069 25.5 15.34 17 -426.850 1.00 15.52 18 (auxiliary aperture) ∞ 1.95 15.76 19 28.067 0.80 2.05090 26.9 16.47 20 18.874 4.30 1.49700 81.5 16.18 21 -68.734 0.80 1.75500 52.3 16.31 22 41.203 0.15 16.50 23 23.795 5.71 1.43875 94.7 17.89 24 -30.878 0.15 19.00 25* 26.669 6.09 1.49700 81.5 20.24 26 -31.980 (variable) 20.40 27 43.537 0.75 1.72916 54.7 19.36 28 23.468 (variable) 18.81 29 -22.555 1.50 1.85400 40.4 19.05 30* -92.996 (variable) 20.61 31 167.684 5.58 1.49700 81.5 37.93 32 -64.072 (variable) 38.64 Image plane ∞ Aspheric data 3rd page K = 0.00000e+000 A 4= 6.47302e-005 A 6=-2.29202e-007 A 8= 5.86104e-010 A10=-1.05964e-012 A12= 1.37744e-015 A14=-8.86881e-019 Side 4 K =-7.50843e-001 A 4= 7.46936e-005 A 6=-1.82700e-007 A 8=-2.68916e-010 A10= 2.54737e-012 A12=-5.55262e-015 A14= 3.33412e-018 Page 25 K = 0.00000e+000 A 4=-2.23064e-005 A 6=-6.28235e-008 A 8= 7.24431e-011 A10=-1.42742e-012 A12=-7.58488e-016 Page 30 K = 0.00000e+000 A 4= 3.94581e-005 A 6= 6.47504e-008 A 8=-2.02428e-010 A10= 4.29810e-014 A12= 3.69126e-015 Various data Zoom ratio 2.06 Wide-angle Mid-range Telephoto Focal length 11.33 17.14 23.30 F-number 4.08 4.08 4.12 Half angle of view (degrees) 50.56 47.28 32.77 Image height 18.57 21.64 21.64 Lens total length 137.09 129.80 130.30 BF 14.83 12.87 11.38 d10 31.31 14.87 6.22 d26 1.40 2.08 2.59 d28 9.65 8.97 8.46 d30 1.34 12.44 23.09 d32 14.83 12.87 11.38 Zoom lens group data Group starting plane focal length 1 1 -21.13 2 11 22.34 3 27 -70.94 4 29 -35.21 5 31 94.03 [Numerical Example 6] Unit: mm Surface Data Surface number rd nd νd Effective diameter 1 50.865 1.40 1.77250 49.6 42.93 2 17.863 7.25 31.67 3* 46.917 2.20 1.58313 59.4 30.93 4* 14.743 9.13 26.03 5 -53.512 1.00 1.49700 81.5 25.74 6 62.328 0.20 25.62 7 33.031 4.22 1.83400 37.2 25.87 8 -1410.574 (variable) 25.42 9 (Aperture) ∞ 0.30 17.61 10 30.753 0.90 1.95375 32.3 18.21 11 14.405 5.01 1.76200 40.1 17.88 12 178.071 1.00 17.95 13 28.952 0.90 1.72916 54.7 18.24 14 14.470 6.76 1.51633 64.1 17.75 15 -34.922 1.48 17.69 16 -34.130 0.70 1.55963 61.2 17.22 17 75.243 (variable) 17.21 18 37.725 0.90 1.80400 46.5 17.53 19 15.470 4.31 1.49700 81.5 17.17 20 110.900 0.15 17.36 21 26.976 4.77 1.49700 81.5 18.66 22 -40.410 0.15 19.20 23* 217.132 4.72 1.49700 81.5 19.39 24* -22.828 (variable) 19.86 25 -76007.456 0.75 1.80400 46.5 18.82 26 20.698 (variable) 18.48 27* -170.981 1.60 1.85400 40.4 21.99 28* 998.468 (variable) 22.94 29 2090.313 5.34 1.49700 81.5 38.25 30 -51.796 14.02 38.93 Image plane ∞ Aspheric data 3rd page K = 0.00000e+000 A 4= 4.47960e-005 A 6=-3.48481e-007 A 8= 1.44040e-009 A10=-3.42659e-012 A12= 4.42059e-015 A14=-2.38393e-018 Side 4 K =-6.48193e-001 A 4= 5.35870e-005 A 6=-3.21360e-007 A 8=-3.48686e-010 A10= 1.17717e-011 A12=-5.28294e-014 A14= 7.55482e-017 Page 23 K = 0.00000e+000 A 4=-4.71833e-005 A 6=-8.44077e-008 A 8= 1.47111e-009 A10=-1.06774e-011 A12= 7.11865e-014 Page 24 K = 0.00000e+000 A 4=-7.69334e-006 A 6=-6.90014e-008 A 8= 1.57448e-009 A10=-1.47829e-011 A12= 8.11251e-014 Page 27 K = 0.00000e+000 A 4= 1.74890e-006 A 6=-3.81796e-009 A 8= 1.07601e-009 A10=-1.19626e-011 A12= 2.22566e-014 Page 28 K = 0.00000e+000 A 4= 9.96899e-006 A 6=-2.31241e-008 A 8= 1.03976e-009 A10=-1.09841e-011 A12= 2.47861e-014 Various data Zoom ratio 2.35 Wide-angle Mid-range Telephoto Focal length 14.42 23.99 33.95 F-number 4.08 4.08 4.12 Half angle of view (degrees) 46.13 32.01 23.84 Image height 17.92 21.64 21.64 Lens total length 125.86 115.15 121.59 BF 14.02 14.02 14.02 d 8 29.65 8.75 2.71 d17 5.30 4.07 2.19 d24 2.53 3.95 3.78 d26 7.71 6.29 6.46 d28 1.50 12.92 27.28 Zoom lens group data Group starting plane focal length 1 1 -22.76 2 9 55.69 3 18 21.12 4 25 -25.74 5 27 -170.83 6 29 101.78 [Numerical Example 7] Unit: mm Surface Data Surface number rd nd νd Effective diameter 1 45.081 2.10 1.76385 48.5 60.00 2 20.763 7.83 40.66 3* 39.376 2.60 1.58313 59.4 39.57 4* 19.086 12.09 34.05 5 -149.535 1.30 1.49700 81.5 33.35 6 42.685 3.55 30.11 7 -195.828 1.20 1.43875 94.7 29.98 8 27.111 1.08 27.96 9 34.838 4.66 1.72047 34.7 27.96 10 -508.780 (variable) 27.40 11 (Aperture) ∞ 0.50 13.28 12 22.100 0.90 1.88300 40.8 13.77 13 13.090 5.48 1.51633 64.1 13.51 14 -22.254 1.47 13.77 15 -21.928 0.70 1.83481 42.7 13.50 16 20.583 3.00 2.00069 25.5 14.08 17 -124.353 1.00 14.26 18 (auxiliary aperture) ∞ 2.22 14.40 19 28.757 0.80 2.05090 26.9 14.77 20 16.081 6.47 1.49700 81.5 14.44 21 -17.564 0.80 1.75500 52.3 15.27 22 167.455 0.15 16.78 23 29.244 5.87 1.43875 94.7 18.47 24 -25.744 0.15 19.61 25* 31.191 6.27 1.49700 81.5 20.72 26 -27.179 (variable) 20.92 27 29.696 0.75 1.72916 54.7 19.29 28 17.581 (variable) 18.46 29 -23.901 1.50 1.85400 40.4 18.65 30* 280.595 0.26 20.33 31 36.229 2.49 1.72825 28.5 22.47 32 118.225 (variable) 22.96 Image plane ∞ Aspheric data 3rd page K = 0.00000e+000 A 4= 7.28829e-005 A 6=-3.12387e-007 A 8= 1.01671e-009 A10=-2.11222e-012 A12= 2.79184e-015 A14=-1.84122e-018 Side 4 K =-5.56940e-001 A 4= 8.13645e-005 A 6=-2.68703e-007 A 8=-1.48487e-010 A10= 4.94390e-012 A12=-1.70106e-014 A14= 1.68710e-017 Page 25 K = 0.00000e+000 A 4=-2.30258e-005 A 6=-6.54896e-008 A 8= 1.46618e-010 A10=-1.94958e-012 A12= 6.26213e-015 Page 30 K = 0.00000e+000 A 4= 4.62125e-005 A 6= 1.37240e-008 A 8= 4.45799e-010 A10=-4.84100e-012 A12= 1.52924e-014 Various data Zoom ratio 2.06 Wide-angle Mid-range Telephoto Focal length 11.33 16.77 23.30 F-number 4.08 4.08 4.12 Half angle of view (degrees) 52.93 41.82 32.77 Image height 18.57 21.64 21.64 Lens total length 135.25 125.30 120.88 BF 16.69 22.62 28.39 d10 31.65 14.80 3.48 d26 1.40 1.53 2.50 d28 8.34 9.17 9.32 d32 16.69 22.62 28.39 Zoom lens group data Group starting plane focal length 1 1 -19.40 2 11 21.92 3 27 -60.68 4 29 -40.75 The various values ​​in each numerical example are summarized in Table 1 below.

[0065] [Table 1]

[0066] [Imaging device] Next, an embodiment of a digital still camera (image capture device) using the zoom lens L0 of each embodiment as an image capture optical system will be described with reference to Fig. 22. In Fig. 22, 10 denotes a camera body, and 11 denotes an image capture optical system constituted by any of the zoom lenses L0 described in Embodiments 1 to 7. 12 denotes a solid-state image capture element (photoelectric conversion element) such as a CCD sensor or CMOS sensor that is built into the camera body and receives and photoelectrically converts an optical image formed by the image capture optical system 11. 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.

[0067] In this way, by applying the zoom lens L0 of each embodiment to an imaging device such as a digital still camera, an imaging device with a small lens can be obtained.

[0068] 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]

[0069] L0 zoom lens L1 First lens group LR rear group LIS subgroup LN final lens group

Claims

1. A zoom lens comprising, arranged in order from the object side to the image side, a first lens group having negative refractive power and a rear group including at least three lens groups and having positive refractive power as a whole, wherein the spacing between adjacent lens groups changes during zooming, the rear group includes a subgroup that moves in a direction including a component perpendicular to the optical axis during image blur correction, the first lens group includes three or more negative lenses arranged in order from the object side to the image side, the rear group includes a focus group having negative refractive power that moves during focusing; When the amount of distortion at the maximum image height when focusing on infinity at the wide-angle end is Dist_w, the focal length of the first lens group is f1, the focal length of the final lens group arranged closest to the image side in the zoom lens is fLN, and the back focus of the zoom lens at the wide-angle end is skw, -20<Dist_w<-8 -0.4<f1 / fLN<0.7 -2.2<f1 / skw≦-1.21 A zoom lens characterized by satisfying the following conditional expressions:

2. When the focal length of the subgroup is f, and the focal length of the zoom lens at the telephoto end is ft, 1.0<|fLIS / ft|<4.0 2. The zoom lens according to claim 1, wherein the following condition is satisfied:

3. When the distance on the optical axis from the lens surface of the rear group closest to the object side to the lens surface of the partial group closest to the object side at the telephoto end is dIS, and the total lens length of the zoom lens at the telephoto end is dt, 0.00≦dIS / dt<0.25 3. The zoom lens according to claim 1, wherein the following condition is satisfied:

4. When the distance on the optical axis from the lens surface of the subgroup closest to the object side to the lens surface of the subgroup closest to the image side is defined as dLIS, and the distance on the optical axis from the lens surface of the subgroup closest to the image side at the wide-angle end to the lens surface of the lens group closest to the object side that is disposed adjacent to the subgroup on the image side is defined as dR, 0.1<dLIS / dR<10.0 4. The zoom lens according to claim 1, wherein the following condition is satisfied:

5. When the Abbe number of the lens with the shortest focal length included in the subgroup is ν, 30<νLIS<70 5. The zoom lens according to claim 1, wherein the following condition is satisfied:

6. When the radius of curvature of the lens surface of the subgroup closest to the object side is r1 and the radius of curvature of the lens surface of the subgroup closest to the image side is r2, -1.0<(r1+r2) / (r1-r2)<0.6 6. The zoom lens according to claim 1, wherein the following condition is satisfied:

7. When the focal length of the zoom lens at the wide-angle end is fw, -2.2<f1 / fw<-1.0 7. The zoom lens according to claim 1, wherein the following condition is satisfied:

8. When the focal length of the zoom lens at the wide-angle end is fw, -0.5<fw / fLN<0.3 8. The zoom lens according to claim 1, wherein the following condition is satisfied:

9. When the maximum image height at the wide-angle end is Ymax_w, -1.5<Ymax_w / f1<-0.5 9. The zoom lens according to claim 1, wherein the following condition is satisfied:

10. 10. The zoom lens according to claim 1, wherein the sub-group includes a positive lens and a negative lens.

11. 11. The zoom lens according to claim 1, wherein the rear group includes two or more lens groups that are arranged on the image side of the partial group and whose spacing changes during zooming.

12. 12. The zoom lens according to claim 1, wherein the focus group is disposed closer to the image side than the partial group.

13. 13. The zoom lens according to claim 1, wherein, at a wide-angle end, the distance between the first lens group and the rear lens group is the greatest among the distances between the lens groups included in the zoom lens.

14. 14. The zoom lens according to claim 1, wherein the first lens group includes a positive lens.

15. 15. The zoom lens according to claim 1, further comprising a storage unit that stores distortion correction data for correcting distortion occurring in the zoom lens.

16. 16. The zoom lens according to claim 1, wherein the rear group consists of, arranged in order from the object side to the image side, a second lens group having positive refractive power, a third lens group having negative refractive power, a fourth lens group having negative refractive power, and a fifth lens group having positive refractive power.

17. 16. The zoom lens according to claim 1, wherein the rear group consists of, arranged in order from the object side to the image side, a second lens group having positive refractive power, a third lens group having negative refractive power, a fourth lens group having positive refractive power, a fifth lens group having negative refractive power, and a sixth lens group having positive refractive power.

18. 16. The zoom lens according to claim 1, wherein the rear group consists of, arranged in order from the object side to the image side, a second lens group having positive refractive power, a third lens group having positive refractive power, a fourth lens group having negative refractive power, a fifth lens group having negative refractive power, and a sixth lens group having positive refractive power.

19. 16. The zoom lens according to claim 1, wherein the rear group consists of, arranged in order from the object side to the image side, a second lens group having positive refractive power, a third lens group having negative refractive power, a fourth lens group having positive refractive power, a fifth lens group having negative refractive power, a sixth lens group having negative refractive power, and a seventh lens group having positive refractive power.

20. 16. The zoom lens according to claim 1, wherein the rear group consists of, arranged in order from the object side to the image side, a second lens group having a positive refractive power, a third lens group having a negative refractive power, and a fourth lens group having a negative refractive power.

21. 21. An imaging device comprising: the zoom lens according to claim 1; and an imaging element that receives an image formed by the zoom lens.

Images