Zoom lens and image capturing device

Abstract

To provide a zoom lens which is compact and compatible with a large-format sensor, and has a high zoom ratio.SOLUTION: A zoom lens disclosed herein consists of a first lens group U1 with positive refractive power configured to be stationary for zooming, multiple intermediate lens groups including a lens group U2 with negative refractive power and two lens groups U3, U4 with positive refractive power, both being configured to move for zooming, and a final lens group U5 located on the most image side and configured to be stationary for zooming. The first lens group includes at least five positive lenses. A composite imaging magnification βzt of all lens groups included in the intermediate lens groups at the telephoto end, and an imaging magnification βrw of the final lens group at the wide-angle end satisfy conditions expressed as: 2.1≤βzt≤4.0, and 1.5≤βrw≤2.1.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a zoom lens suitable for imaging. [Background technology]

[0002] Zoom lenses are expected to be compact, have a wide angle of view, a high zoom ratio, and exhibit high optical performance. Furthermore, for use in cameras equipped with large-format image sensors, zoom lenses with corresponding image sizes are required. Patent documents 1 and 2 disclose zoom lenses compatible with such large-format sensors, which are arranged in order from the object side: a positive first lens group that does not move for zooming, at least two lens groups that move for zooming, and a positive final lens group that also does not move for zooming. These zoom lenses are inner-focus type zoom lenses that include a focus group that moves for focusing within the first lens group. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2020-056491 [Patent Document 2] Patent Publication No. 2021-063885 Summary of the Invention [Problem to be solved by the invention]

[0004] In a zoom lens compatible with a large-format sensor, in order to achieve both compactness and high zoom ratio while maintaining high optical performance throughout the entire zoom range, it is necessary to appropriately set the imaging magnification of each lens group. In the zoom lenses disclosed in Patent Documents 1 and 2, the imaging magnification of the final lens group is insufficient, which results in the imaging magnification of the lens group that moves for zooming on the object side becoming too large. As a result, this is detrimental to the compactness of the zoom lens.

[0005] The present invention provides a zoom lens that is compatible with large-format sensors, is compact, has a high zoom ratio, and exhibits high optical performance across the entire zoom range. [Means for solving the problem]

[0006] A zoom lens according to one aspect of the present invention comprises lens groups arranged in order from the object side to the image side: a first lens group with positive refractive power that does not move for zooming; multiple intermediate lens groups including a lens group with negative refractive power and two lens groups with positive refractive power that each move for zooming; and a final lens group closest to the image side that also does not move for zooming. The spacing between adjacent lens groups changes during zooming. The first lens group includes at least five positive lenses. When the combined imaging magnification of all lens groups included in the intermediate lens group at the telephoto end is βzt and the imaging magnification of the final lens group at the wide-angle end is βrw, 2.1≦βzt≦4.0 1.5≦βrw≦2.1 The present invention is characterized in that the following conditions are satisfied: An imaging device including the zoom lens described above also constitutes another aspect of the present invention. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a zoom lens that is compatible with large-format sensors, is compact, has a high zoom ratio, and has high optical performance over the entire zoom range. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a cross-sectional view of a zoom lens according to a first embodiment in a state where the zoom lens is focused at infinity and at the wide-angle end. [Figure 2] 1A to 1C are aberration diagrams of the zoom lens of Example 1 at infinity focus and at (A) the wide-angle end, (B) the intermediate zoom position, and (C) the telephoto end. [Figure 3] FIG. 10 is a cross-sectional view of the zoom lens of the second embodiment at the infinity focus state and at the wide-angle end. [Figure 4]10A to 10C are aberration diagrams of the zoom lens of Example 2 at infinity focus and at (A) the wide-angle end, (B) the intermediate zoom position, and (C) the telephoto end. [Figure 5] FIG. 11 is a cross-sectional view of the zoom lens of Example 3 at the infinity focus state and wide-angle end. [Figure 6] 10A to 10C are aberration diagrams of the zoom lens of Example 3 at infinity focus and at (A) the wide-angle end, (B) the intermediate zoom position, and (C) the telephoto end. [Figure 7] FIG. 10 is a cross-sectional view of the zoom lens of Example 4 at the infinity focus state and wide-angle end. [Figure 8] 10A to 10C are aberration diagrams of the zoom lens of Example 4 at infinity focus and at (A) the wide-angle end, (B) the intermediate zoom position, and (C) the telephoto end. [Figure 9] FIG. 10 is a cross-sectional view of the zoom lens of Example 5 at the infinity focus state and at the wide-angle end. [Figure 10] 10A to 10C are aberration diagrams of the zoom lens of Example 5 at infinity focus and at (A) the wide-angle end, (B) the intermediate zoom position, and (C) the telephoto end. [Figure 11] FIG. 1 is a schematic diagram of an imaging device equipped with a zoom lens according to any one of Examples 1 to 5. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present invention will be described with reference to the drawings. First, prior to describing specific embodiments 1 to 4, matters common to all embodiments will be described.

[0010] 1, 3, 5, 7, and 9 show cross sections of the zoom lenses of Examples 1, 2, 3, 4, and 5, respectively, when focused on an object at infinity (hereinafter referred to as the infinity focused state) at the wide-angle end. In each figure, the left side is the object side (front side), and the right side is the image side (rear side). The zoom lenses of each Example are used for imaging by imaging devices such as broadcast cameras, cinema cameras, video cameras, surveillance cameras, digital still cameras, and silver halide film cameras.

[0011] The zoom lens of each embodiment is configured with lens groups arranged in order from the object side to the image side, including a first lens group U1 with positive refractive power that does not move for zooming, multiple intermediate lens groups (U2 to U4 or U5) including a lens group with negative refractive power and two lens groups with positive refractive power that each move for zooming, and a final lens group (U5 or U6) closest to the image side that also does not move for zooming.

[0012] In a zoom lens, a lens group is a group of one or more lenses that may or may not move as a unit during zooming between the wide-angle and telephoto ends. That is, the spacing between adjacent lens groups changes during zooming. The lens groups may include an aperture stop. The wide-angle and telephoto ends refer to the zoom states with the maximum and minimum angles of view (shortest focal lengths) when the lens group that moves during zooming is located at the ends of its mechanically or controllably movable range on the optical axis.

[0013] In each figure, SP denotes the aperture stop, and IP denotes the image plane, where the imaging surface (light-receiving surface) of an imaging element such as a CCD sensor or CMOS sensor, or the film surface (photosensitive surface) of a silver halide film, is located.

[0014] In the zoom lens of each embodiment, the first lens group, which is the heaviest among the lens groups, remains stationary during zooming, thereby reducing the size of the zoom lens drive mechanism. Also, by imparting positive refractive power to the first lens group, the diameter of light rays incident on the intermediate lens group, mainly at the telephoto end, is reduced, thereby reducing the size of the lens groups that move during zooming.

[0015] Furthermore, in the zoom lenses of each embodiment, by making the final lens group immovable during zooming, it is possible to arrange an extender that increases the focal length over the entire zoom range or an adjustment mechanism that adjusts the flange focal length within the final lens group.

[0016] In addition, in the zoom lens of each embodiment, the multiple intermediate lens groups each include a lens group with negative refractive power that moves for zooming and two lens groups with positive refractive power, thereby achieving both a high zoom ratio and good aberration correction, thereby achieving high optical performance. Furthermore, in the zoom lens of each embodiment, the first lens group U1 includes at least five positive lenses. By configuring the first lens group U1 with at least five positive lenses, the positive refractive power of the first lens group U1 is shared, thereby achieving suppression of spherical aberration at the telephoto end. (Reason added.) Note that for a cemented lens in which N lenses are cemented together, the number of lenses is N.

[0017] The zoom lens of each embodiment satisfies the conditions of the following expressions (1) and (2), where βzt is the composite imaging magnification of all lens groups included in the multiple intermediate lens groups at the telephoto end, and βrw is the imaging magnification of the final lens group at the wide-angle end.

[0018] 2.1≦βzt≦4.0 (1) 1.5≦βrw≦2.1 (2) By having βzt and βrw satisfy the conditions of equations (1) and (2), respectively, a zoom lens compatible with large-format sensors is achieved that is both compact and has a high zoom ratio. If βzt exceeds the upper limit of equation (1), the combined imaging magnification of the multiple intermediate lens groups at the telephoto end becomes too large, making it difficult to correct axial chromatic aberration and lateral chromatic aberration at the telephoto end, which is undesirable. If βzt falls below the lower limit of equation (1), the combined imaging magnification of the multiple intermediate lens groups at the telephoto end becomes too small, making it impossible to obtain a sufficiently long focal length at the telephoto end and making it difficult to achieve a high zoom ratio, which is also undesirable.

[0019] If βrw exceeds the upper limit of formula (2), the imaging magnification of the final lens group becomes too large, which is undesirable when increasing the aperture of the zoom lens, and if βrw falls below the lower limit of formula (2), the focal length of each lens group included in the multiple intermediate lens groups becomes too long when attempting to accommodate a large-format sensor, which is undesirable when increasing the overall length of the zoom lens.

[0020] It is more preferable to set the numerical ranges of the formulas (1) and (2) as follows:

[0021] 2.105≦βzt≦3.000 (1a) 1.60≦βrw≦2.00 (2a) Furthermore, it is more preferable to set the numerical ranges of the formulas (1) and (2) as follows:

[0022] 2.107≦βzt≦2.800 (1b) 1.62≦βrw≦1.95 (2b) By satisfying the above configuration and conditions, it is possible to realize a zoom lens that is compatible with large-format sensors, is compact, has a high zoom ratio, and exhibits high optical performance across the entire zoom range.

[0023] Conditions that the zoom lens of each embodiment preferably satisfies are described below: The zoom lens of each embodiment preferably satisfies at least one of the conditions and configurations of the following expressions (3) to (7).

[0024] Furthermore, the imaging magnifications at the wide-angle end and the telephoto end of the lens group having negative refractive power as the intermediate lens group are respectively denoted as βnw and βnt, and the combined imaging magnifications at the wide-angle end and the telephoto end of all lens groups among the plurality of intermediate lens groups that are arranged closer to the image than the lens group having negative refractive power are respectively denoted as βpw and βpt. In this case, it is preferable that the zoom lens of each embodiment satisfies the condition of the following formula (3).

[0025] 2.0≦|(βnt / βnw) / (βpt / βpw)|≦4.0 (3) The condition of formula (3) indicates the appropriate relationship of imaging magnification between the lens group with negative refractive power included in the multiple intermediate lens groups and all lens groups located closer to the image side than the lens group with negative refractive power, i.e., the magnification sharing. If |(βnt / βnw) / (βpt / βpw)| exceeds the upper limit of formula (3), the magnification sharing of the lens group with negative refractive power as the intermediate lens group becomes too large. As a result, the movement amount of the lens group with negative refractive power during zooming becomes too large, or the refractive power of the lens group with negative refractive power becomes too strong, making it difficult to correct chromatic aberration of magnification throughout the entire zoom range, which is undesirable. If |(βnt / βnw) / (βpt / βpw)| falls below the lower limit of formula (3), the magnification sharing of all lens groups located closer to the image side than the lens group with negative refractive power among the multiple intermediate lens groups becomes too large. As a result, the amount of movement of the two intermediate lens groups with positive refractive power during zooming becomes too large, or the refractive power of the two positive refractive power lens groups becomes too strong, making it difficult to correct axial chromatic aberration throughout the entire zoom range, which is undesirable.

[0026] It is more preferable to set the numerical range of the formula (3) as follows:

[0027] 2.5≦|(βnt / βnw) / (βpt / βpw)|≦3.5 (3a) Furthermore, it is more preferable to set the numerical range of the formula (3) as follows.

[0028] 2.7≦|(βnt / βnw) / (βpt / βpw)|≦3.0 (3b) In the zoom lens of each embodiment, it is preferable that the condition of the following formula (4) be satisfied, where f1 is the focal length of the first lens unit U1 having positive refractive power and fn is the focal length of the lens unit having negative refractive power as the intermediate lens unit.

[0029] 6.0≦|f1 / fn|≦10.0 (4) If |f1 / fn| exceeds the upper limit of formula (4), the focal length of the first lens unit U1 becomes too long, and the amount of movement of the lens unit with negative refractive power as the intermediate lens unit becomes too large to widen the angle of view at the wide-angle end, which is undesirable. If |f1 / fn| falls below the lower limit of formula (4), the focal length of the first lens unit U1 becomes too short, and the combined imaging magnification of the multiple intermediate lens units becomes too large to achieve a long focal length at the telephoto end. As a result, it becomes difficult to correct axial chromatic aberration and chromatic aberration of magnification at the telephoto end, which is undesirable.

[0030] It is more preferable to set the numerical range of the formula (4) as follows:

[0031] 6.5≦|f1 / fn|≦9.0 (4a) Furthermore, it is more preferable to set the numerical range of the formula (4) as follows.

[0032] 7.5≦|f1 / fn|≦8.9 (4b) In the zoom lens of each embodiment, when the focal length of the lens group with negative refractive power as the intermediate lens group is denoted by fn, and the composite focal length at the telephoto end of all lens groups that are arranged on the image side of the lens group with negative refractive power among the multiple intermediate lens groups is denoted by fpt, ​​it is preferable that the condition of the following equation (5) be satisfied:

[0033] 2.0≦|fpt / fn|≦4.0 (5) If |fpt / fn| exceeds the upper limit of formula (5), the composite refractive power at the telephoto end of all lens groups that are located closer to the image than the lens group with negative refractive power among the multiple intermediate lens groups becomes too strong. As a result, it becomes difficult to correct axial chromatic aberration in the telephoto range, which is undesirable. If |fpt / fn| falls below the lower limit of formula (5), the composite refractive power at the telephoto end of all lens groups that are located closer to the image than the lens group with negative refractive power among the multiple intermediate lens groups becomes too weak. As a result, it becomes difficult to obtain sufficient imaging magnification in the telephoto range of all lens groups that are located closer to the image than the lens group with negative refractive power among the multiple intermediate lens groups, which makes it difficult to achieve a long focal length at the telephoto end, which is undesirable.

[0034] It is more preferable to set the numerical range of the formula (5) as follows:

[0035] 2.3≦|fpt / fn|≦3.0 (5a) Furthermore, it is more preferable to set the numerical range of the formula (5) as follows.

[0036] 2.40≦|fpt / fn|≦2.55 (5b) In the zoom lens of each embodiment, when the focal length of the final lens unit that does not move for zooming is fi, it is preferable that the condition of the following expression (6) be satisfied.

[0037] 2.0≦|fi / f1|≦20.0 (6) If |fi / f1| exceeds the upper limit of equation (6), the refractive power of the final lens group becomes too weak, the distance from the final lens group to the image plane becomes too long, and the overall length of the zoom lens increases, which is undesirable. If |fi / f1| falls below the lower limit of equation (6), the imaging magnification of the final lens group cannot be increased, and the focal length of the first lens group or the intermediate lens group must be increased to accommodate large-format sensors. This results in an undesirable increase in the overall length.

[0038] It is more preferable to set the numerical range of the formula (6) as follows:

[0039] 2.1≦|fi / f1|≦18.0 (6a) Furthermore, it is more preferable to set the numerical range of the formula (6) as follows.

[0040] 2.2≦|fi / f1|≦17.0 (6b) In the zoom lens of each embodiment, when the first lens unit U1 includes a negative lens and the focal length of the negative lens is f1n, it is preferable that the condition of the following expression (7) be satisfied.

[0041] 1.2≦|f1n / f1|≦2.0 (7) If |f1n / f1| exceeds the upper limit of equation (7), the refractive power of the negative lens in the first lens unit becomes too weak, and the color correction effect when the refractive power of the first lens unit U1 is increased becomes insufficient, making it difficult to correct axial chromatic aberration and lateral chromatic aberration at the telephoto end, which is undesirable.If |f1n / f1| falls below the lower limit of equation (7), the refractive power of the negative lens becomes too strong, making it difficult to correct distortion at the wide-angle end, which is undesirable.

[0042] It is more preferable to set the numerical range of the formula (7) as follows:

[0043] 1.3≦|f1n / f1|≦1.6 (7a) Furthermore, it is more preferable to set the numerical range of the formula (7) as follows.

[0044] 1.4≦|f1n / f1|≦1.5 (7b) Furthermore, in the zoom lenses of each embodiment, it is preferable that the lens group with negative refractive power serving as the intermediate lens group be composed of four negative lenses and two positive lenses. By thus configuring the lens group with negative refractive power shared by four negative lenses and including two positive lenses, it becomes possible to suppress chromatic aberration of magnification throughout the entire zoom range.

[0045] The zoom lenses of Examples 1 to 5 will be specifically described below.

[0046] [Examples 1 to 4] The zoom lenses of Examples 1 to 4 shown in Figures 1, 3, 5, and 7 are configured, arranged in order from the object side to the image side, with a first lens unit U1 having positive refractive power and not moving for zooming; a second lens unit U2 having negative refractive power, a third lens unit U3 having positive refractive power, and a fourth lens unit U4 having positive refractive power, each of which moves for zooming; an aperture stop SP; and a fifth lens unit (final lens unit) U5 having positive refractive power for imaging and not moving for zooming. The second lens unit U2 to the fourth lens unit U4 are intermediate lens units. In each figure, arrows below each lens unit that moves for zooming indicate the path that the lens unit moves as it zooms from the wide-angle end to the telephoto end.

[0047] The first lens group U1, which has positive refractive power, is composed of one negative lens closest to the object and five positive lenses. From the object side to the image side, it has a first subgroup U11, a second subgroup U12, and a third subgroup U13, each of which has positive refractive power. A subgroup is a group of one or more lenses that may or may not move together during focusing between an infinity-focused state and a state where the lens is focused on a close object (hereinafter referred to as the close-up focused state). The second subgroup U12 moves toward the object side as indicated by the arrow (FOCUS) in the figure for focusing from infinity to a close object. The third subgroup U3 moves toward the object side independently of the second subgroup U2 for focusing from infinity to a close object.

[0048] The second lens unit U2, which has negative refractive power, is a variator lens unit that moves toward the image side during zooming from the wide-angle end to the telephoto end. The second lens unit U2 is made up of four negative lenses and two positive lenses.

[0049] The third lens unit U3, which has a positive refractive power, moves toward the image side and then toward the object side during zooming from the wide-angle end to the telephoto end. The third lens unit U3 is composed of two positive lenses and one negative lens.

[0050] The fourth lens unit U4, which has a positive refractive power, moves toward the image side and then toward the object side independently of the third lens unit U3 during zooming from the wide-angle end to the telephoto end. The fourth lens unit U4 is composed of two positive lenses and one negative lens.

[0051] The aperture stop SP is disposed closest to the object in the fifth lens unit U5. A shift lens for optical image stabilization may be disposed within the fifth lens unit U5, which has a positive refractive power, or a lens unit such as the aforementioned extender lens may be disposed so as to be insertable and detachable.

[0052] [Example 5] 9 is composed of, arranged in order from the object side to the image side, a first lens unit U1 with a positive refractive power that does not move for zooming, a second lens unit U2 with a negative refractive power, a third lens unit U3 with a positive refractive power, a fourth lens unit U4 with a positive refractive power, and a fifth lens unit U5 with a positive refractive power that each move for zooming, an aperture stop SP, and a sixth lens unit (final lens unit) U6 with a positive refractive power for imaging that does not move for zooming. The second lens unit U2 to the fifth lens unit U5 are intermediate lens units.

[0053] The first lens group U1, which has positive refractive power, is composed of one negative lens closest to the object and five positive lenses. From the object side to the image side, it has a first subgroup U11, a second subgroup U12, and a third subgroup U13, each of which has positive refractive power. The second subgroup U12 moves toward the object side for focusing from infinity to close objects. The third subgroup U13 moves toward the object side independently of the second subgroup U12 for focusing from infinity to close objects.

[0054] The second lens unit U2, which has negative refractive power, is a variator unit that moves toward the image side during zooming from the wide-angle end to the telephoto end. The second lens unit U2 is made up of four negative lenses and two positive lenses.

[0055] The third lens unit U3, which has a positive refractive power, moves toward the image side and then toward the object side during zooming from the wide-angle end to the telephoto end. The third lens unit U3 is made up of one positive lens.

[0056] The fourth lens unit U4, which has positive refractive power, moves toward the image side and then toward the object side independently of the third lens unit U3 during zooming from the wide-angle end to the telephoto end. The fourth lens unit U4 is composed of one positive lens and one negative lens.

[0057] The fifth lens unit U4, which has a positive refractive power, moves toward the image side and then toward the object side independently of the third and fourth lens units U3 and U4 during zooming from the wide-angle end to the telephoto end. The fifth lens unit U5 is composed of two positive lenses and one negative lens.

[0058] The aperture stop SP is disposed closest to the object in the sixth lens unit U6. A shift lens for optical image stabilization may be disposed within the sixth lens unit U6, which has a positive refractive power, or a lens unit such as an extender lens may be disposed so as to be insertable and detachable.

[0059] Numerical Examples 1 to 5 corresponding to Examples 1 to 5, respectively, are shown below. In each numerical example, surface number i indicates the order of the surface when counted from the object side. r is the radius of curvature (mm) of the ith surface from the object side, d is the lens thickness or air gap (mm) on the optical axis between the ith and (i+1)th surfaces, and nd is the refractive index at the d-line of the optical material between the ith and (i+1)th surfaces. νd is the Abbe number based on the d-line of the optical material between the ith and (i+1)th surfaces.

[0060] The Abbe number νd based on the d-line is expressed as νd=(Nd-1) / (NF-NC), where Nd, NF, and NC are the refractive indices at the Fraunhofer d-line (587.6 nm), F-line (486.1 nm), and C-line (656.3 nm).

[0061] BF represents back focal length (mm). Back focal length is the distance on the optical axis from the lens surface closest to the image (the final surface) of a zoom lens to the paraxial image plane, expressed as the air-equivalent length. The total lens length is the distance on the optical axis from the lens surface closest to the object (the frontmost surface) to the final surface, plus the back focal length.

[0062] An "*" next to a surface number indicates that the surface has an aspherical shape. The aspherical shape is expressed by the following formula, where X is the displacement from the vertex of the surface in the optical axis direction, H is the height from the optical axis in a direction perpendicular to the optical axis, the direction of light travel is positive, R is the paraxial radius of curvature, K is the conic constant, and A4, A6, A8, A10, and A12 are aspherical coefficients. The conic constant and the aspherical coefficients "e±Z" are expressed as x 10 ±Z means.

[0063]

number

[0064] The values ​​of formulas (1) to (7) in Numerical Examples 1 to 5 are summarized in Table 1. Numerical Examples 1 to 5 all satisfy the conditions of formulas (1) to (7).

[0065] Figures 2, 4, 6, 8, and 10 show longitudinal aberrations (spherical aberration, astigmatism, distortion, and chromatic aberration) at infinity focus at (A) the wide-angle end, (B) the mid-zoom position, and (C) the telephoto end. In the spherical aberration diagrams, Fno indicates the F-number, the solid line indicates spherical aberration at the e-line (wavelength 546.1 nm), and the dashed line indicates spherical aberration at the g-line (wavelength 435.8 nm). In the astigmatism diagrams, the solid line S indicates astigmatism at the sagittal image plane, and the dashed line M indicates astigmatism at the meridional image plane. The distortion diagrams show distortion at the e-line. The chromatic aberration diagrams show lateral chromatic aberration at the g-line. ω is the half angle of view (°). The scales are as follows: spherical aberration 0.4mm, astigmatism 0.4mm, distortion 5%, and lateral chromatic aberration 0.05mm. [Numerical example 1] Unit: mm Surface Data Surface number rd nd νd 1 -2350.850 4.40 1.83481 42.7 2 355.756 2.00 3 361.505 26.36 1.43387 95.1 4 -788.700 0.12 5 927.238 13.44 1.43387 95.1 6 -1672.211 25.35 7 394.952 17.22 1.43387 95.1 8 ∞ 0.12 9 324.444 24.39 1.43700 95.1 10 -1336.384 1.59 11 177.686 16.27 1.43700 95.1 12 334.570 (variable) 13* -890.028 2.20 1.90366 31.3 14 53.485 11.04 15 -109.709 1.45 1.83481 42.7 16 706.222 3.07 1.85478 24.8 17 -354.737 3.16 18 -85.253 1.45 1.76385 48.5 19 76.084 12.30 1.84666 23.8 20 -66.624 2.38 21 -51.299 2.00 1.76385 48.5 22 -142.913 (variable) 23 115.236 12.05 1.76385 48.5 24* -1066.947 2.58 25 113.680 17.36 1.43875 94.7 26 -159.166 3.01 27 452.878 2.50 1.78880 28.4 28 82.003 (variable) 29 80.226 14.72 1.43875 94.7 30 -683.586 2.50 2.00069 25.5 31 1668.782 0.20 32* 217.470 10.65 1.43875 94.7 33 -138.010 (variable) 34 (Aperture) ∞ 4.80 35 9180.324 1.40 1.88300 40.8 36 39.566 0.91 37 34.227 3.41 1.89286 20.4 38 60.083 4.78 39 -78.643 1.50 1.88300 40.8 40 186.937 9.16 41 88.618 1.50 2.00100 29.1 42 34.395 4.79 1.89286 20.4 43 60.450 0.20 44 39.255 1.50 1.95375 32.3 45 30.534 13.36 1.48749 70.2 46 -84.454 6.32 47 259.109 4.37 1.72825 28.5 48 -63.514 0.20 49 -356.691 1.50 1.77250 49.6 50 201.648 4.64 1.49700 81.5 51 561.456 0.20 52 136.856 8.19 1.71736 29.5 53 -30.564 1.50 1.85896 22.7 54 315.170 7.49 55 -41.859 1.20 2.00100 29.1 56 464.031 4.03 1.76182 26.5 57 -63.273 0.20 58 2550.455 4.15 1.62004 36.3 59 -55.632 (variable) Image plane ∞ Aspheric data Page 13 K = 1.35971e+00 A 4= 4.27264e-07 A 6=-4.76620e-11 A 8=-5.33274e-14 A10= 2.38678e-17 A12= 2.47527e-20 Page 24 K = 2.00111e+00 A 4= 3.19681e-07 A 6= 2.98373e-13 A 8= 6.32615e-15 A10=-1.79800e-18 A12= 2.70592e-22 Page 32 K = 2.00017e+00 A 4=-5.60292e-07 A 6=-5.95842e-11 A 8= 4.93762e-15 A10= 1.41736e-17 A12=-5.59890e-21 Various data Zoom ratio 39.22 Wide-angle Mid-range Telephoto Focal length 25.50 596.55 1000.09 F-number 2.90 2.90 4.86 Half angle of view (°) 30.13 1.42 0.85 Image height 14.80 14.80 14.80 Lens total length 674.06 674.06 674.06 BF 66.38 66.38 66.38 d12 3.79 177.36 181.18 d22 253.93 41.89 2.45 d28 20.77 16.55 24.95 d33 2.00 44.69 71.91 d59 66.38 66.38 66.38 Lens group data Group starting plane focal length 1 1 256.50 2 13 -33.85 3 23 136.64 4 29 112.75 5 34 4303.32 [Numerical example 2] Unit: mm Surface Data Surface number rd nd νd 1 -2560.191 4.40 1.83481 42.7 2 357.759 2.00 3 363.708 26.40 1.43387 95.1 4 -719.427 0.12 5 695.974 13.82 1.43387 95.1 6 -1953.559 26.82 7 367.150 16.45 1.43387 95.1 8 ∞ 0.12 9 343.029 19.93 1.43700 95.1 10 -1728.117 1.60 11 177.435 12.67 1.43700 95.1 12 290.369 (variable) 13* 2861.426 2.20 1.90366 31.3 14 52.288 11.95 15 -87.578 1.45 1.83481 42.7 16 118.276 4.94 1.85478 24.8 17 -505.788 3.05 18 -92.892 1.45 1.76385 48.5 19 94.919 10.41 1.84666 23.8 20 -68.242 1.43 21 -58.158 2.00 1.76385 48.5 22 -213.883 (variable) 23 105.860 11.08 1.76385 48.5 24* 1316.068 5.25 25 173.847 13.39 1.43875 94.7 26 -159.231 0.49 27 202.149 2.50 1.78880 28.4 28 84.086 (variable) 29 80.957 13.88 1.43875 94.7 30 -624.889 2.50 2.00069 25.5 31 786.166 0.20 32* 199.433 11.20 1.43875 94.7 33 -136.370 (variable) 34 (Aperture) ∞ 4.80 35 4007.174 1.40 1.88300 40.8 36 44.356 0.91 37 37.475 3.41 1.89286 20.4 38 63.158 4.78 39 -75.254 1.50 1.88300 40.8 40 196.467 9.16 41 79.718 1.50 2.00100 29.1 42 38.263 4.43 1.89286 20.4 43 60.455 0.20 44 39.552 1.50 1.95375 32.3 45 30.322 13.72 1.48749 70.2 46 -83.355 6.32 47 128.475 5.48 1.72825 28.5 48 -75.336 0.20 49 -356.691 1.50 1.77250 49.6 50 201.648 4.64 1.49700 81.5 51 561.456 0.20 52 59.848 6.57 1.71736 29.5 53 -41.154 1.50 1.85896 22.7 54 55.919 5.91 55 -45.359 1.20 2.00100 29.1 56 78.702 5.72 1.76182 26.5 57 -50.655 0.20 58 105.824 5.47 1.62004 36.3 59 -126.405 (variable) Image plane ∞ Aspheric data Page 13 K = 2.00000e+00 A 4= 2.28484e-07 A 6=-6.60675e-11 A 8= 6.89903e-14 A10=-1.14553e-16 A12= 5.84143e-20 Page 24 K =-1.25540e+00 A 4= 3.04209e-07 A 6= 9.66247e-12 A 8=-9.30988e-15 A10=6.96949e-18 A12=-1.61568e-21 Page 32 K = 1.20163e+00 A 4=-5.09134e-07 A 6=-1.65422e-11 A 8=-4.55007e-14 A10=4.27595e-17 A12=-1.16472e-20 Various data Zoom ratio 41.67 Wide-angle Mid-range Telephoto Focal length 24.00 564.31 1000.18 F-number 2.90 2.90 5.14 Half angle of view (°) 31.66 1.50 0.85 Image height 14.80 14.80 14.80 Lens total length 671.05 671.05 671.05 BF 67.61 67.61 67.61 d12 3.57 182.67 188.30 d22 240.04 40.32 7.89 d28 41.90 5.01 3.69 d33 2.00 59.51 87.64 d59 67.61 67.61 67.61 Lens group data Group starting plane focal length 1 1 262.00 2 13 -31.62 3 23 144.18 4 29 119.99 5 34 740.99 [Numerical example 3] Unit: mm Surface Data Surface number rd nd νd 1 -2400.689 4.40 1.83481 42.7 2 350.441 2.00 3 355.986 26.30 1.43387 95.1 4 -760.231 0.12 5 730.348 13.86 1.43387 95.1 6 -1738.428 24.55 7 367.892 17.06 1.43387 95.1 8 -13552.994 0.12 9 331.740 20.65 1.43700 95.1 10 -1735.401 1.60 11 179.305 13.67 1.43700 95.1 12 314.259 (variable) 13* 4719.166 2.20 1.90366 31.3 14 51.554 11.60 15 -91.667 1.45 1.83481 42.7 16 125.484 4.98 1.85478 24.8 17 -335.480 2.94 18 -85.612 1.45 1.76385 48.5 19 89.905 10.34 1.84666 23.8 20 -67.139 1.44 21 -56.981 2.00 1.76385 48.5 22 -281.008 (variable) 23 105.369 10.68 1.76385 48.5 24* 1802.433 4.99 25 179.259 13.95 1.43875 94.7 26 -151.851 0.45 27 201.195 2.50 1.78880 28.4 28 83.790 (variable) 29 77.718 13.90 1.43875 94.7 30 -563.130 2.50 2.00069 25.5 31 754.083 0.20 32* 189.342 12.45 1.43875 94.7 33 -126.664 (variable) 34 (Aperture) ∞ 4.80 35 -12047.629 1.40 1.88300 40.8 36 41.189 0.91 37 35.365 3.41 1.89286 20.4 38 62.959 4.78 39 -78.307 1.50 1.88300 40.8 40 196.405 9.16 41 90.974 1.50 2.00100 29.1 42 38.678 4.25 1.89286 20.4 43 57.737 0.20 44 38.698 1.50 1.95375 32.3 45 29.323 13.90 1.48749 70.2 46 -83.312 8.70 47 117.059 5.96 1.72825 28.5 48 -69.257 0.20 49 -356.691 1.50 1.77250 49.6 50 201.648 4.64 1.49700 81.5 51 561.456 0.20 52 76.158 7.61 1.71736 29.5 53 -40.383 1.50 1.85896 22.7 54 72.720 5.22 55 -52.926 1.20 2.00100 29.1 56 62.255 5.65 1.76182 26.5 57 -63.758 0.20 58 117.183 5.44 1.62004 36.3 59 -115.580 (variable) Image plane ∞ Aspheric data Page 13 K = 2.00000e+00 A 4= 2.68187e-07 A 6=-7.77843e-11 A 8= 9.05450e-14 A10=-1.52335e-16 A12= 7.99263e-20 Page 24 K = 1.99998e+00 A 4= 3.20309e-07 A 6= 9.07568e-12 A 8=-6.42348e-15 A10=4.87186e-18 A12=-1.09782e-21 Page 32 K = 9.55198e-02 A 4=-5.77680e-07 A 6=-1.82725e-11 A 8=-5.36329e-14 A10=4.92214e-17 A12=-1.29296e-20 Various data Zoom ratio 48.32 Wide-angle Mid-range Telephoto Focal length 23.80 559.66 1150.01 F-number 2.90 2.90 5.90 Half angle of view (°) 31.88 1.51 0.74 Image height 14.80 14.80 14.80 Lens total length 665.65 665.65 665.65 BF 66.47 66.47 66.47 d12 3.53 177.91 184.44 d22 239.47 42.47 2.34 d28 34.49 4.98 3.60 d33 2.00 54.12 89.11 d59 66.47 66.47 66.47 Lens group data Group starting plane focal length 1 1 255.56 2 13 -30.51 3 23 139.62 4 29 114.73 5 34 1647.02 [Numerical example 4] Unit: mm Surface Data Surface number rd nd νd 1 -2598.305 4.40 1.83481 42.7 2 351.758 2.00 3 355.184 24.59 1.43387 95.1 4 -846.027 0.12 5 674.170 12.65 1.43387 95.1 6 -1696.713 22.28 7 397.019 15.35 1.43387 95.1 8 -15120.284 0.12 9 325.664 20.31 1.43700 95.1 10 -1783.396 1.59 11 176.365 13.87 1.43700 95.1 12 318.643 (variable) 13* 1374.359 2.20 1.90366 31.3 14 48.941 12.30 15 -81.299 1.45 1.83481 42.7 16 145.635 4.62 1.85478 24.8 17 -336.082 2.87 18 -86.932 1.45 1.76385 48.5 19 96.267 9.30 1.85896 22.7 20 -71.821 1.30 21 -61.031 2.00 1.76385 48.5 22 -241.900 (variable) 23 101.831 10.03 1.76385 48.5 24* 916.574 5.03 25 182.663 13.35 1.43875 94.7 26 -154.984 0.44 27 195.420 2.50 1.78880 28.4 28 81.687 (variable) 29 77.187 14.05 1.43875 94.7 30 -527.648 2.50 2.00069 25.5 31 952.288 0.20 32* 198.612 12.11 1.43875 94.7 33 -126.277 (variable) 34 (Aperture) ∞ 4.80 35 495.287 1.40 1.88300 40.8 36 43.022 0.91 37 37.043 3.41 1.89286 20.4 38 66.059 4.78 39 -80.887 1.50 1.88300 40.8 40 195.403 9.16 41 137.704 1.50 2.00100 29.1 42 39.957 4.49 1.89286 20.4 43 74.570 0.20 44 42.666 1.50 1.95375 32.3 45 31.943 13.65 1.48749 70.2 46 -83.414 10.51 47 116.218 5.78 1.72825 28.5 48 -70.234 0.20 49 -356.691 1.50 1.77250 49.6 50 201.648 4.64 1.49700 81.5 51 561.456 0.20 52 62.783 6.50 1.71736 29.5 53 -40.747 1.50 1.85896 22.7 54 52.114 5.69 55 -51.742 1.20 2.00100 29.1 56 68.887 5.63 1.76182 26.5 57 -54.789 0.20 58 83.169 3.59 1.62004 36.3 59 -215.395 (variable) Image plane ∞ Aspheric data Page 13 K =-1.99999e+00 A 4= 2.29895e-07 A 6=-8.90207e-11 A 8= 1.37989e-13 A10=-2.45408e-16 A12= 1.22118e-19 Page 24 K = 2.00233e+00 A 4= 3.15771e-07 A 6= 1.18929e-11 A 8=-9.07210e-15 A10=6.14724e-18 A12=-1.33008e-21 Page 32 K = 1.46678e+00 A 4=-6.06374e-07 A 6=-1.15822e-11 A 8=-5.80334e-14 A10=4.96151e-17 A12=-1.26061e-20 Various data Zoom ratio 52.18 Wide-angle Mid-range Telephoto Focal length 23.00 540.97 1200.19 F-number 2.90 2.90 6.24 Half angle of view (°) 32.76 1.57 0.71 Image height 14.80 14.80 14.80 Lens total length 660.46 660.46 660.46 BF 66.52 66.52 66.52 d12 3.40 178.76 185.72 d22 243.34 48.22 2.44 d28 35.80 5.90 6.20 d33 2.00 51.67 90.19 d59 66.52 66.52 66.52 Lens group data Group starting plane focal length 1 1 255.01 2 13 -29.83 3 23 146.81 4 29 112.90 5 34 3400.84 [Numerical example 5] Unit: mm Surface Data Surface number rd nd νd 1 -2949.791 4.50 1.83481 42.7 2 352.957 1.30 3 347.294 24.35 1.43387 95.1 4 -897.579 0.20 5 571.959 13.48 1.43387 95.1 6 -2023.134 23.09 7 407.594 14.59 1.43387 95.1 8 25837.750 0.25 9 384.716 17.03 1.43387 95.1 10 -2508.051 1.60 11 178.124 15.97 1.43387 95.1 12 379.711 (variable) 13* 877.444 2.00 1.88300 40.8 14 45.513 11.57 15 -106.695 3.27 1.85478 24.8 16 -73.368 1.60 2.00100 29.1 17 -273.528 4.30 18 -61.583 1.50 1.76385 48.5 19 96.635 11.32 1.85478 24.8 20 -49.408 1.35 21 -43.793 1.65 1.75500 52.3 22 -161.420 (variable) 23 112.270 12.47 1.76385 48.5 24* -4681.476 (variable) 25 116.048 16.47 1.43875 94.7 26 -171.368 0.50 27 222.294 2.50 1.78880 28.4 28 71.781 (variable) 29 70.420 14.82 1.43875 94.7 30 -819.275 2.30 1.78880 28.4 31 453.819 0.20 32* 160.030 9.39 1.49700 81.5 33 -187.647 (variable) 34 (Aperture) ∞ 5.70 35 1703.727 1.40 1.88300 40.8 36 52.137 0.96 37 35.787 3.68 1.89286 20.4 38 67.046 3.94 39 -217.530 1.50 1.88300 40.8 40 72.829 10.12 41 200.183 1.50 2.00100 29.1 42 29.918 5.55 1.77830 23.9 43 87.244 0.68 44 36.113 1.50 1.88300 40.8 45 27.938 14.44 1.49700 81.5 46 -139.041 6.95 47 223.491 5.71 1.53172 48.8 48 -50.188 0.20 49 392.667 1.50 1.89190 37.1 50 41.568 0.20 51 34.900 11.51 1.58913 61.1 52 44.105 1.24 53 53.802 4.45 1.54814 45.8 54 24161.728 4.03 55 -29.985 1.20 1.76385 48.5 56 50.220 7.13 1.85478 24.8 57 -57.929 4.34 58 70.502 8.53 1.56732 42.8 59 -35.342 1.20 1.95906 17.5 60 -83.895 (variable) Image plane ∞ Aspheric data Page 13 K = 2.00000e+00 A 4= 4.02568e-07 A 6= 2.18372e-11 A 8=-1.59954e-13 A10= 2.16400e-17 A12= 5.42209e-19 A14=-7.27782e-22 A16= 3.11984e-25 Page 24 K = 2.00000e+00 A 4= 2.74196e-07 A 6= 3.26329e-12 A 8= 2.84445e-15 A10=3.97003e-20 A12=-1.26556e-22 Page 32 K =-2.30668e-01 A 4=-4.68840e-07 A 6=-6.54710e-11 A 8= 1.04820e-14 A10=3.74249e-18 A12=-2.10842e-21 Various data Zoom ratio 57.60 Wide-angle Mid-range Telephoto Focal length 22.88 450.46 1317.80 F-number 2.90 2.90 6.86 Half angle of view (°) 32.90 1.88 0.64 Image height 14.80 14.80 14.80 Lens total length 666.62 666.62 666.62 BF 52.00 52.00 52.00 d12 3.05 179.96 191.25 d22 253.16 61.58 2.00 d24 8.14 2.10 6.40 d28 25.36 3.37 2.75 d33 2.20 44.89 89.51 d60 52.00 52.00 52.00 Lens group data Group starting plane focal length 1 1 261.14 2 13 -29.49 3 23 143.00 4 25 -1317.48 5 29 105.85 6 34 598.87

[0066] [Table 1]

[0067] [Imaging device] Fig. 11 shows an imaging device (broadcast camera) 125 equipped with the zoom lens of any one of Examples 1 to 5 as an imaging optical system. In Fig. 11, 101 denotes an imaging optical system configured with the zoom lens of any one of Examples 1 to 5. 124 denotes a camera body. The imaging optical system 101 is detachable from the camera body 124. However, the imaging optical system may be configured integrally with the camera body.

[0068] The imaging optical system 101 has a first lens group F, a zoom section LZ, and an imaging lens group R. The first lens group F includes a sub-group that moves during focusing. The zoom section LZ includes multiple lens groups that move during zooming. SP is an aperture stop.

[0069] Reference numerals 114 and 115 denote driving mechanisms such as helicoids or cams that drive the subgroups of the first lens group F and the zoom section LZ in the optical axis direction. Reference numerals 116 to 118 denote motors that drive the driving mechanisms 114 and 115 and the aperture diaphragm SP, respectively. Reference numerals 119 to 121 denote detectors such as encoders, potentiometers, or photosensors that detect the positions on the optical axis of the subgroups of the first lens group F and the multiple lens groups that make up the zoom section LZ, and the aperture diameter of the aperture diaphragm SP. In the camera body 124, reference numeral 109 denotes a glass block that corresponds to an optical filter within the camera 124. Reference numeral 110 denotes an imaging element (photoelectric conversion element) such as a CCD sensor or CMOS sensor that photoelectrically converts the subject image formed by the imaging optical system 101 (i.e., captures the subject through the zoom lens). Reference numerals 111 and 122 denote control units such as a CPU that control the driving of the camera body 124 and the imaging optical system 101.

[0070] In this way, by using the zoom lens of each embodiment as an imaging optical system, it is possible to obtain high-quality images with a high zoom ratio in an imaging device having a large-format sensor.

[0071] The above embodiment includes the following configurations.

[0072] (Configuration 1) A zoom lens in which the lens groups arranged in order from the object side to the image side are composed of a first lens group with positive refractive power that does not move for zooming, a plurality of intermediate lens groups including a lens group with negative refractive power and two lens groups with positive refractive power that each move for zooming, and a final lens group closest to the image side that does not move for zooming, and in which the spacing between adjacent lens groups changes during zooming, the first lens group includes at least five positive lenses; When the composite imaging magnification of all the lens groups included in the intermediate lens group at the telephoto end is βzt and the imaging magnification of the final lens group at the wide-angle end is βrw, 2.1≦βzt≦4.0 1.5≦βrw≦2.1 A zoom lens characterized by satisfying the following conditions: (Configuration 2) When the image-forming magnifications at the wide-angle end and the telephoto end of the lens group having negative refractive power as the intermediate lens group are respectively βnw and βnt, and the composite image-forming magnifications at the wide-angle end and the telephoto end of all lens groups among the plurality of intermediate lens groups that are located on the image side of the lens group having negative refractive power are respectively βpw and βpt, 2.0≦|(βnt / βnw) / (βpt / βpw)|≦4.0 The zoom lens according to configuration 1, characterized in that the following condition is satisfied: (Configuration 3) When the focal length of the first lens group is f1 and the focal length of the lens group having negative refractive power as the intermediate lens group is fn, 6.0≦|f1 / fn|≦10.0 3. The zoom lens according to configuration 1 or 2, characterized in that the following conditions are satisfied: (Configuration 4) When the focal length of the lens group having negative refractive power as the intermediate lens group is defined as fn, and the composite focal length at the telephoto end of all lens groups among the plurality of intermediate lens groups that are arranged closer to the image side than the lens group having negative refractive power is defined as fpt, 2.0≦|fpt / fn|≦4.0 4. The zoom lens according to any one of configurations 1 to 3, wherein the following condition is satisfied: (Configuration 5) When the focal length of the first lens group is f1 and the focal length of the final lens group is fi, 2.0≦|fi / f1|≦20.0 5. The zoom lens according to any one of configurations 1 to 4, wherein the following condition is satisfied: (Configuration 6) the first lens group has a negative lens, When the focal length of the first lens group is f1 and the focal length of the negative lens is f1n, 1.2≦|f1n / f1|≦2.0 6. The zoom lens according to any one of configurations 1 to 5, wherein the following condition is satisfied: (Configuration 7) 7. The zoom lens of any one of configurations 1 to 6, wherein the lens group having negative refractive power as the intermediate lens group is composed of four negative lenses and two positive lenses. (Configuration 8) The zoom lens according to any one of configurations 1 to 7, characterized in that the lens groups arranged in order from the object side to the image side comprise the first lens group, a second lens group with negative refractive power that moves for zooming, a third lens group with positive refractive power, and a fourth lens group with positive refractive power, and a fifth lens group as the final lens group with positive refractive power. (Configuration 9) 8. The zoom lens according to any one of configurations 1 to 7, wherein the lens groups arranged in order from the object side to the image side comprise the first lens group, a second lens group with negative refractive power that moves for zooming, a third lens group with positive refractive power, a fourth lens group with positive refractive power, and a fifth lens group with positive refractive power, and a sixth lens group as the final lens group with positive refractive power. (Configuration 10) the zoom lens according to any one of configurations 1 to 9; and an image sensor for capturing an image of a subject through the zoom lens.

[0073] The embodiments described above are merely representative examples, and various modifications and alterations are possible to each embodiment when implementing the present invention. [Explanation of symbols]

[0074] U1 First lens group U2 Second lens group U3 Third lens group U4 4th lens group U5 Fifth lens group U6 6th lens group SP aperture stop

Claims

1. A zoom lens in which the lens groups arranged in order from the object side to the image side are composed of a first lens group with positive refractive power that does not move for zooming, a plurality of intermediate lens groups including a lens group with negative refractive power and two lens groups with positive refractive power that each move for zooming, and a final lens group closest to the image side that does not move for zooming, and in which the spacing between adjacent lens groups changes during zooming, the first lens group includes at least five positive lenses; When the combined imaging magnification of all the lens groups included in the intermediate lens group at the telephoto end is βzt and the imaging magnification of the final lens group at the wide-angle end is βrw, 2.1≦βzt≦4.0 1.5≦βrw≦2.1 A zoom lens characterized by satisfying the following conditions:

2. Let βnw and βnt be the image-forming magnifications at the wide-angle end and the telephoto end of the lens group having negative refractive power as the intermediate lens group, respectively, and βpw and βpt be the composite image-forming magnifications at the wide-angle end and the telephoto end of all lens groups among the plurality of intermediate lens groups that are located on the image side of the lens group having negative refractive power, respectively. 2.0≦|(βnt / βnw) / (βpt / βpw)|≦4.0 2. The zoom lens according to claim 1, wherein the following condition is satisfied:

3. When the focal length of the first lens group is f1 and the focal length of the lens group having negative refractive power as the intermediate lens group is fn, 6.0≦|f1 / fn|≦10.0 2. The zoom lens according to claim 1, wherein the following condition is satisfied:

4. Let fn be the focal length of the lens group having negative refractive power as the intermediate lens group, and fpt be the composite focal length at the telephoto end of all lens groups among the plurality of intermediate lens groups that are arranged closer to the image side than the lens group having negative refractive power, 2.0≦|fpt / fn|≦4.0 2. The zoom lens according to claim 1, wherein the following condition is satisfied:

5. When the focal length of the first lens group is f1 and the focal length of the final lens group is fi, 2.0≦|fi / f1|≦20.0 2. The zoom lens according to claim 1, wherein the following condition is satisfied:

6. the first lens group has a negative lens; When the focal length of the first lens group is f1 and the focal length of the negative lens is f1n, 1.2≦|f1n / f1|≦2.0 2. The zoom lens according to claim 1, wherein the following condition is satisfied:

7. 2. A zoom lens according to claim 1, wherein said lens group having negative refractive power as said intermediate lens group is composed of four negative lenses and two positive lenses.

8. 2. The zoom lens according to claim 1, wherein the lens groups arranged in this order from the object side to the image side comprise the first lens group, a second lens group having negative refractive power, a third lens group having positive refractive power, and a fourth lens group having positive refractive power, each of which moves for zooming, and a fifth lens group having positive refractive power as the final lens group.

9. 2. The zoom lens according to claim 1, wherein the lens groups arranged in order from the object side to the image side comprise the first lens group, a second lens group having negative refractive power, a third lens group having positive refractive power, a fourth lens group having positive refractive power, and a fifth lens group having positive refractive power, each of which moves for zooming, and a sixth lens group having positive refractive power as the final lens group.

10. The zoom lens according to any one of claims 1 to 9; and an image sensor for capturing an image of a subject through the zoom lens.

Images