Zoom lens and imaging device

Abstract

There is a demand for a compact zoom lens with a wider angle of view and higher zoom magnification than conventional lenses. [Solution] The zoom lens is composed of a first lens group L1 with positive refractive power that does not move for zooming, three or more movable lens groups that move for zooming, and a second lens group N with positive refractive power. The three or more movable lens groups include a second lens group (N-1) with positive refractive power, a second lens group (N-2) with negative refractive power, and one or more V lens groups, arranged in order from the image side to the object side. The first lens group includes a focus group that moves for focusing. The second lens group (N-1) is located closer to the image at the telephoto end than it is at the wide-angle end. The second lens group N is composed of a front sub-lens group and a rear sub-lens group, arranged in order from the object side with the widest air gap between them. -2.2≦Σ(f1 / fVi)≦-0.4 and 2.0≦β(N-1)w≦18.5 are satisfied.

Description

Technical Field

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

Background Art

[0002] Zoom lenses are required to be small in size while having a wide angle of view and high optical performance. Patent Document 1 discloses a zoom lens composed of a first lens group having a positive refractive power that does not move for zooming, a plurality of lens groups that move for zooming, and a rear lens group having a positive refractive power that does not move for zooming, which are arranged in order from the object side to the image side.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] A small-sized zoom lens with a wider angle of view and a higher zoom ratio than conventional ones is desired.

Means for Solving the Problems

[0005] One aspect of the present invention is a zoom lens which includes a plurality of lens groups. The plurality of lens groups consist of a first lens group with positive refractive power that does not move for zooming, arranged sequentially from the object side to the image side, three or more movable lens groups that move for zooming, and the Nth lens group with positive refractive power as the final lens group, and the spacing between adjacent lens groups changes when zooming. The three or more movable lens groups include the (N-1)th lens group with positive refractive power, the (N-2)th lens group with negative refractive power, and one or more V lens groups, arranged sequentially from the image side to the object side. The first lens group includes a focus group that moves for focusing. The (N-1)th lens group is located closer to the image at the telephoto end than it is at the wide-angle end. The Nth lens group consists of a front sub-lens group and a rear sub-lens group arranged sequentially from the object side with the widest air gap between them.

[0006] Let f1 be the focal length of the first lens group, fVi be the focal length of the i-th moving lens group from the object side among one or more V lens groups, and let Σ(f1 / fVi) be the sum of f1 / fVi. Let β(N-1)w be the lateral magnification at the wide-angle end of the (N-1) lens group, LE be the length along the optical axis of the widest air gap in the N lens group, LR be the length along the optical axis from the object-side surface of the N lens group to the image-side surface of the N lens group, and βrr be the lateral magnification at the wide-angle end of the rear sub-lens group. -2.2≦Σ(f1 / fVi)≦-0.4 2.0 ≤ β(N-1)w ≤ 18.5 0.3 ≤ LE / LR ≤ 0.7 -0.8 ≤ βrr ≤ 0.8 It is characterized by satisfying the following conditions. Furthermore, an imaging device equipped with the above-mentioned zoom lens 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 compact yet has a wide angle of view and high zoom magnification. [Brief explanation of the drawing]

[0008] [Figure 1] Cross-sectional view of the zoom lens of Example 1 at its wide-angle end. [Figure 2] Aberration diagrams of the zoom lens of Example 1 at the (A) wide-angle end and (B) telephoto end. [Figure 3] Cross-sectional view of the zoom lens of Example 2 at its wide-angle end. [Figure 4] Aberration diagrams of the zoom lens of Example 2 at the (A) wide-angle end and (B) telephoto end. [Figure 5] Cross-sectional view of the zoom lens of Example 3 at its wide-angle end. [Figure 6] Aberration diagrams of the zoom lens of Example 3 at the (A) wide-angle end and (B) telephoto end. [Figure 7] Cross-sectional view of the zoom lens of Example 4 at its wide-angle end. [Figure 8] Aberration diagrams of the zoom lens of Example 4 at the (A) wide-angle end and (B) telephoto end. [Figure 9] Cross-sectional view of the zoom lens of Example 5 at its wide-angle end. [Figure 10] Aberration diagrams of the zoom lens of Example 5 at the (A) wide-angle end and (B) telephoto end. [Figure 11] Cross-sectional view of the zoom lens of Example 6 at its wide-angle end. [Figure 12] Aberration diagrams of the zoom lens of Example 6 at the (A) wide-angle end and (B) telephoto end. [Figure 13] Cross-sectional view of the zoom lens of Example 7 at its wide-angle end. [Figure 14] Aberration diagrams of the zoom lens of Example 7 at the (A) wide-angle end and (B) telephoto end. [Figure 15] A diagram showing an imaging device using a zoom lens in each embodiment. [Modes for carrying out the invention]

[0009] The embodiments of the present invention will be described below with reference to the drawings. First, before describing the specific embodiments 1 to 7, we will explain the matters common to each embodiment.

[0010] The zoom lenses of each embodiment are used in various imaging devices such as cinema cameras, broadcast cameras, video cameras, surveillance cameras, digital still cameras, cameras for silver halide films, etc. In the zoom lens, the lens group is a collection of one or more lenses that move integrally or do not move during zooming (changing magnification) between the wide-angle end and the telephoto end. That is, the distance between adjacent lens groups changes during zooming. The lens group may include an aperture stop. The wide-angle end and the telephoto end respectively indicate the zoom states of the maximum picture angle (shortest focal length) and the minimum picture angle (longest focal length) when the lens group that moves during zooming is located at both ends of the range where it can move mechanically or under control on the optical axis.

[0011] FIG. 1, FIG. 3, FIG. 5, FIG. 7, FIG. 9, FIG. 11, and FIG. 13 respectively show cross-sections at the wide-angle end in a state where the zoom lenses of Examples 1 to 7 are focused on an infinite object (hereinafter referred to as an infinite focus state). In each figure, the left side is the object side (front side), and the right side is the image side (rear side). OA indicates the optical axis of the zoom lens.

[0012] Li is the i-th lens group (i = 1, 2,...) counted from the object side, and L1m is the m-th sub-lens group (m = 1, 2,...) counted from the object side in the first lens group L1. The sub-lens group is a collection of one or more lenses that move integrally or do not move during focusing. SP is the aperture stop, and I is the image plane. On the image plane I, the imaging surface (light-receiving surface) of the imaging element in the imaging device or the film surface (photosensitive surface) of the silver halide film is arranged.

[0013] In each figure, under the lens group that moves during zooming, the movement trajectory of the lens group during zooming from the wide-angle end to the telephoto end is indicated by an arrow. Further, under the sub-lens group that moves during focusing in the first lens group L1, the movement direction of the sub-lens group during focusing from infinity to the closest distance is indicated by an arrow marked with FOCUS.

[0014] Each embodiment of the zoom lens includes multiple lens groups. The multiple lens groups consist of a first lens group L1 with positive refractive power that does not move for zooming, arranged sequentially from the object side to the image side; three or more movable lens groups L2 to L4 (or L5) that move for zooming; and the Nth lens group LN (N=5 or 6) as the final lens group with positive refractive power that does not move for zooming. The three or more movable lens groups include the (N-1)th lens group with positive refractive power, the (N-2)th lens group with negative refractive power, and one or more V lens groups, arranged sequentially from the image side to the object side.

[0015] Furthermore, the first lens group L1 includes a focus group that moves for focusing. In addition, the (N-1) lens group is located closer to the image at the telephoto end than it is at the wide-angle end. Moreover, the N lens group consists of a front sub-lens group and a rear sub-lens group, which are arranged from the object side to the image side with the widest possible air gap between them.

[0016] Let f1 be the focal length of the first lens group L1. Let fVi be the focal length of the i-th moving lens group from the object side among one or more V lens groups, and let Σ be the sum of f1 / fVi. Let β(N-1)w be the lateral magnification at the wide-angle end of the (N-1) lens group, LE be the length along the optical axis of the widest air gap in the N lens group, LR be the length along the optical axis from the object-side surface of the N lens group to the image-side surface of the N lens group, and βrr be the lateral magnification at the wide-angle end of the rear sub-lens group. In this case, it is preferable that the zoom lens of each embodiment satisfies at least one of the following equations (1) to (4).

[0017] -2.2≦Σ(f1 / fVi)≦-0.4 (1) 2.0 ≤ β(N-1)w ≤ 18.5 (2) 0.3 ≤ LE / LR ≤ 0.7 (3) -0.8 ≤ βrr ≤ 0.8 (4) The conditions in equation (1) indicate an appropriate relationship between the combined focal length of the first lens group L1 and one or more V lens groups from among three or more movable lens groups that significantly contribute to achieving the zoom ratio. Satisfying the conditions in equation (1) makes it possible to realize a compact, lightweight zoom lens with a refractive power arrangement that is advantageous for achieving high zoom magnification. If Σ(f1 / fVi) exceeds the upper limit of equation (1), the combined refractive power of the V lens group V becomes too weak compared to the refractive power of the first lens group L1, making it difficult to achieve high zoom magnification, which is undesirable. If Σ(f1 / fVi) falls below the lower limit of equation (1), the combined refractive power of the V lens group V becomes too strong, resulting in large aberration fluctuations during zooming, or making it difficult to make the zoom lens compact and lightweight if aberration fluctuations are suppressed, which is also undesirable.

[0018] Furthermore, it is more preferable to set the lower limit of formula (1) to -2.0, -1.8, or -1.7, and the upper limit of formula (1) to -0.5, -0.6, or -0.65.

[0019] The conditions in equation (2) indicate an appropriate range for the lateral magnification at the wide-angle end of the (N-1) lens group. Satisfying the conditions in equation (2) makes it possible to achieve an arrangement that is advantageous for high zoom magnification. If β(N-1)w exceeds the upper limit of equation (2), the light rays emitted from the (N-1) lens group become closer to parallel rays, making it difficult to obtain the magnification effect during zooming, which is undesirable. If β(N-1)w falls below the lower limit of equation (2), the light rays emitted from the (N-1) lens group diverge more, making the final lens group larger and making it difficult to miniaturize the zoom lens, which is also undesirable.

[0020] Furthermore, it is more preferable to set the lower limit of formula (2) to 2.4, 2.6, or 2.8, and the upper limit of formula (2) to 18.0, 17.0, or 16.0.

[0021] The condition in equation (3) indicates the condition under which an optical unit such as an extender can be inserted into or removed from the widest air gap in the Nth lens group. By satisfying the condition in equation (3), a zoom lens in which an optical unit can be inserted into or removed can be realized. If LE / LR exceeds the upper limit of equation (3), the gap between the front and rear sub-lens groups in the final lens group becomes too wide, which is undesirable as it makes the zoom lens larger. If LE / LR falls below the lower limit of equation (3), it is undesirable as it does not provide enough space to insert or remove the optical unit.

[0022] Furthermore, it is more preferable to set the lower limit of formula (3) to 0.31, 0.32, or 0.33, and the upper limit of formula (3) to 0.65, 0.6, or 0.55.

[0023] The conditions in equation (4) indicate an appropriate range for the lateral magnification at the wide-angle end of the rear sub-lens group of the final lens group. Satisfying the conditions in equation (4) makes it possible to realize a zoom lens that is small, lightweight, and advantageous in ensuring an appropriate back focus. If βrr exceeds the upper limit of equation (4), it becomes difficult to ensure a back focus, which is undesirable. If βrr falls below the lower limit of equation (4), light rays with a large divergence angle will be incident on the rear sub-lens group, causing the final lens group to become larger, which is also undesirable.

[0024] Furthermore, it is more preferable to set the lower limit of formula (4) to -0.65, -0.5, or -0.4, and the upper limit of formula (4) to 0.65, 0.5, or 0.4.

[0025] By satisfying the above configuration and conditions, it is possible to provide a zoom lens that is compact yet offers a wide angle of view, high optical performance, and an appropriate angle of incidence of light on the image plane.

[0026] Furthermore, it is preferable that the zoom lens of each embodiment satisfies at least one of the following conditions (5) to (9).

[0027] 1.0≦β(N-1)t / β(N-1)w≦1.2 (5) 2.0 ≤ (f1 + bok1) / f1 ≤ 5.0 (6) -3.0≦Σ(f(N-1) / fVi)≦-0.5 (7) 0.0 <Lm / L≦0.3 (8) 1.0 ≤ f1 / fw ≤ 10.0 (9) In equations (5) to (9), β(N-1)t is the lateral magnification of the (N-1)th lens group at the telephoto end. bok1 is the distance along the optical axis from the image-side surface of the first lens group L1 to the rear principal point of the first lens group, with the direction from the object side to the image side being considered positive. f(N-1) is the focal length of the (N-1)th lens group. The sum of f(N-1) / fVi is expressed as Σ(f(N-1) / fVi). Lm is the amount of movement from the object side to the image side when zooming from the wide-angle end to the telephoto end of the lens group with the largest negative refractive power among one or more V lens groups. The amount of movement of the lens group is the difference between the position of the lens group at the wide-angle end and the position of the lens group at the telephoto end, and does not include the amount of reciprocal movement. It is considered positive when the lens group is located on the image side at the telephoto end compared to the wide-angle end. L is the length along the optical axis from the object-side surface of the first lens group L1 to the image-side surface of the Nth lens group. fw is the focal length of the entire zoom lens system at the wide-angle end.

[0028] The conditions in equation (5) indicate an appropriate range for the zoom ratio β(N-1)t / β(N-1)w of the (N-1) lens group. If the zoom ratio exceeds the upper limit of equation (5), the amount of movement of the (N-1) lens group becomes too large, making it difficult to miniaturize the zoom lens, which is undesirable. If the zoom ratio falls below the lower limit of equation (5), the (N-1) lens group will undergo a reduction in magnification, making it difficult to increase the zoom magnification of the zoom lens, which is also undesirable.

[0029] Furthermore, it is more preferable to set the lower limit of formula (5) to 1.005 or 1.01, and the upper limit of formula (5) to 1.19, 1.17, 1.15, or 1.10.

[0030] The conditions in equation (6) indicate an appropriate relationship between the distance on the optical axis from the image-side surface of the first lens group L1 to the rear principal point of the first lens group, and the focal length of the first lens group L1, in order to obtain a wide-angle, compact, and lightweight zoom lens. If (f1+bok1) / f1 exceeds the upper limit of equation (6), the rear principal point of the first lens group L1 will be positioned excessively on the image side, increasing the diameter of the lens positioned on the image side of the first lens group L1, which is undesirable as it is disadvantageous to obtaining a compact and lightweight zoom lens. If (f1+bok1) / f1 falls below the lower limit of equation (6), the focal length of the first lens group L1 will become too long, making it difficult to achieve a wide angle of view, which is also undesirable.

[0031] Furthermore, it is more preferable to set the lower limit of formula (6) to 2.2, 2.3, or 2.4, and the upper limit of formula (6) to 4.5, 4.2, or 4.0.

[0032] The conditions in equation (7) indicate an appropriate relationship between the combined focal length of the (N-1) lens group and one or more V lens groups. If Σ(f(N-1) / fVi) exceeds the upper limit of equation (7), the refractive power of the V lens group, which greatly contributes to zooming, becomes too weak, the amount of movement of the V lens group increases, and it becomes difficult to miniaturize the zoom lens, which is undesirable. If Σ(f(N-1) / fVi) falls below the lower limit of equation (7), the refractive power of the (N-1) lens group becomes too weak, the lens diameter of the final lens group increases, and it becomes difficult to miniaturize the zoom lens, which is also undesirable.

[0033] Furthermore, it is more preferable to set the lower limit of equation (7) to -2.6, -2.4, or -2.2, and the upper limit of equation (7) to -0.8, -1.1, or -1.3.

[0034] The conditions in equation (8) indicate an appropriate relationship between the amount of movement of the negative lens group, which contributes significantly to achieving the zoom ratio among three or more moving lens groups, and the length from the object-side surface of the first lens group L1 to the image-side surface of the Nth lens group. If Lm / L exceeds the upper limit of equation (8), the amount of movement of the negative lens group during zooming becomes large, making it difficult to miniaturize the zoom lens, which is undesirable. If Lm / L falls below the lower limit of equation (8), the amount of movement of the negative lens group during zooming becomes small, making it difficult to increase the zoom ratio, which is also undesirable.

[0035] Furthermore, it is more preferable to set the lower limit of formula (8) to 0.05, 0.1, or 0.13, and the upper limit of formula (8) to 0.25, 0.22, or 0.2.

[0036] The conditions in equation (9) indicate an appropriate relationship between the focal length of the first lens group L1 and the focal length of the entire system at the wide-angle end in order to obtain a compact zoom lens with a wide angle of view, high zoom ratio, and high optical performance. If f1 / fw exceeds the upper limit of equation (9), the lens diameter of the first lens group L1 becomes large, making it difficult to obtain a compact zoom lens, which is undesirable. If f1 / fw falls below the lower limit of equation (9), it becomes difficult to obtain a zoom lens with a wide angle of view and high zoom ratio, or it becomes difficult to keep aberrations at the wide-angle end within an acceptable range, which is also undesirable.

[0037] Furthermore, it is more preferable to set the lower limit of formula (9) to 1.5, 2.0, or 2.2, and the upper limit of formula (9) to 9.0, 8.0, 6.0, or 4.0.

[0038] Furthermore, it is preferable that the zoom lens of each embodiment has at least one of the following configurations.

[0039] Preferably, the first lens group L1 includes a first sub-lens group L11 with negative refractive power that does not move for focusing and is positioned on the object side of the focus group that moves for focusing, a second sub-lens group L12 with positive refractive power as the focus group, and a third sub-lens group L13 with positive refractive power that does not move for focusing and is positioned on the image side of the focus group. This configuration is advantageous for widening the angle of the zoom lens.

[0040] Furthermore, it is preferable that the first lens group L1 has six or more lenses. This configuration enables good aberration correction and allows for high optical performance of the zoom lens.

[0041] Furthermore, it is preferable that the (N-1) lens group moves monotonically toward the image when zooming from the wide-angle end to the telephoto end. By moving in this manner, the magnification effect of the (N-1) lens group can be achieved throughout the entire zoom range.

[0042] The zoom lenses for each embodiment will be described in detail below. Furthermore, numerical examples 1 to 7, corresponding to each of Examples 1 to 7, will be shown after Example 7. [Examples]

[0043] The zoom lens of Embodiment 1 (Numerical Example 1) shown in Figure 1 is composed of a first lens group L1 with positive refractive power, a second lens group L2 with negative refractive power, a third lens group L3 with negative refractive power, a fourth lens group L4 with positive refractive power, an aperture diaphragm SP, and a fifth lens group L5 with positive refractive power, arranged in order from the object side to the image side. The first lens group L1 does not move for zooming. The second lens group L2, the third lens group L3, and the fourth lens group L4 constitute three or more movable lens groups that move for zooming. The fifth lens group L5 is the final lens group (Nth lens group) for image formation and does not move for zooming.

[0044] The first lens group L1 consists of a first sub-lens group L11 with negative refractive power, a second sub-lens group L12 with positive refractive power, and a third sub-lens group L13 with positive refractive power, arranged in order from the object side to the image side. The second sub-lens group L12 is a focusing group that moves towards the image side when focusing from infinity to close.

[0045] The second lens group L2 is a variator group (V lens group) that moves toward the image side when zooming from the wide-angle end to the telephoto end. The third lens group ((N-2) lens group) L3 and the fourth lens group ((N-1) lens group) L4 also move toward the image side when zooming from the wide-angle end to the telephoto end. An optical unit such as an extender lens for focal length conversion may be inserted in the widest air gap in the fifth lens group L5.

[0046] Figure 2(A) shows the longitudinal aberrations (spherical aberration, astigmatism, distortion, and chromatic aberration) of the zoom lens of numerical example 1 at infinity focus and the wide-angle end. Figure 2(B) shows the longitudinal aberrations of the zoom lens of numerical example 1 at infinity focus and the telephoto end.

[0047] In the spherical aberration diagram, Fno indicates the F number, the solid line shows the spherical aberration for the d line (wavelength 587.6 nm), and the dashed line shows the spherical aberration for the g line (wavelength 435.8 nm). The dashed line shows the spherical aberration for the C line (wavelength 656.3 nm), and the long dashed line shows the spherical aberration for the F line (wavelength 486.1 nm). In the astigmatism diagram, the solid line S shows astigmatism on the sagittal image plane, and the dashed line M shows astigmatism on the meridional image plane. The distortion diagram shows distortion on the d line. The chromatic aberration diagram shows lateral chromatic aberration on the g, C, and F lines. The astigmatism and chromatic aberration diagrams show the amount of aberration when the central ray of the light beam at the aperture position is considered the principal ray. ω is the paraxial half-angle of view (°). Spherical aberration is depicted on a scale of 0.2 mm, astigmatism on 0.2 mm, distortion on 5%, and chromatic aberration on 0.05 mm. The explanations above for the aberration diagrams also apply to the aberration diagrams in the following numerical examples. [Examples]

[0048] The zoom lens of Embodiment 2 (Numerical Example 2) shown in Figure 3 is composed of a first lens group L1 with positive refractive power, a second lens group L2 with negative refractive power, a third lens group L3 with negative refractive power, a fourth lens group L4 with positive refractive power including the aperture diaphragm SP, and a fifth lens group L5 with positive refractive power, arranged in order from the object side to the image side. The first lens group L1 does not move for zooming. The second lens group L2, the third lens group L3, and the fourth lens group L4 constitute three or more movable lens groups that move for zooming. The fifth lens group L5 is the final lens group (Nth lens group) for image formation and does not move for zooming.

[0049] The first lens group L1 consists of a first sub-lens group L11 with negative refractive power, a second sub-lens group L12 with positive refractive power, and a third sub-lens group L13 with positive refractive power, arranged in order from the object side to the image side. The second sub-lens group L12 is a focusing group that moves towards the image side when focusing from infinity to close.

[0050] The second lens group L2 is a variator group (V lens group) that moves toward the image side when zooming from the wide-angle end to the telephoto end. The third lens group ((N-2) lens group) L3 and the fourth lens group ((N-1) lens group) L4 move toward the image side when zooming from the wide-angle end to the telephoto end. The aperture diaphragm SP moves together with the fourth lens group L4 when zooming. An optical unit such as an extender lens for focal length conversion may be inserted in the widest air gap in the fifth lens group L5.

[0051] Figure 4(A) shows the longitudinal aberration at the wide-angle end and in focus at infinity for the zoom lens of numerical example 2. Figure 4(B) shows the longitudinal aberration at the telephoto end and in focus at infinity for the zoom lens of numerical example 2. [Examples]

[0052] The zoom lens of Embodiment 2 (Numerical Example 2) shown in Figure 5 is composed of a first lens group L1 with positive refractive power, a second lens group L2 with negative refractive power, a third lens group L3 with negative refractive power, an aperture diaphragm SP, a fourth lens group L4 with positive refractive power, and a fifth lens group L5 with positive refractive power, arranged in order from the object side to the image side. The first lens group L1 does not move for zooming. The second lens group L2, the third lens group L3, and the fourth lens group L4 constitute three or more movable lens groups that move for zooming. The fifth lens group L5 is the final lens group (Nth lens group) for image formation and does not move for zooming.

[0053] The first lens group L1 consists of a first sub-lens group L11 with negative refractive power, a second sub-lens group L12 with positive refractive power, and a third sub-lens group L13 with positive refractive power, arranged in order from the object side to the image side. The second sub-lens group L12 is a focusing group that moves towards the image side when focusing from infinity to close.

[0054] The second lens group L2 is a variator group (V lens group) that moves toward the image side when zooming from the wide-angle end to the telephoto end. The third lens group ((N-2) lens group) L3 and the fourth lens group ((N-1) lens group) L4 move toward the image side when zooming from the wide-angle end to the telephoto end. The aperture diaphragm SP moves together with the fourth lens group L4 when zooming. An optical unit such as an extender lens for focal length conversion may be inserted in the widest air gap in the fifth lens group L5.

[0055] Figure 6(A) shows the longitudinal aberrations (spherical aberration, astigmatism, distortion, and chromatic aberration) of the zoom lens of numerical example 3 at infinity focus and the wide-angle end. Figure 6(B) shows the longitudinal aberrations of the zoom lens of numerical example 3 at infinity focus and the telephoto end. [Examples]

[0056] The zoom lens of Embodiment 4 (Numerical Example 4) shown in Figure 7 is composed of a first lens group L1 with positive refractive power, a second lens group L2 with negative refractive power, a third lens group L3 with negative refractive power, a fourth lens group L4 with negative refractive power, a fifth lens group L5 with positive refractive power including the aperture diaphragm SP, and a sixth lens group L6 with positive refractive power, arranged in order from the object side to the image side. The first lens group L1 does not move for zooming. The second lens group L2, third lens group L3, fourth lens group L4, and fifth lens group L5 constitute three or more movable lens groups that move for zooming. The sixth lens group L6 is the final lens group (Nth lens group) for image formation and does not move for zooming.

[0057] The first lens group L1 consists of a first sub-lens group L11 with negative refractive power, a second sub-lens group L12 with positive refractive power, and a third sub-lens group L13 with positive refractive power, arranged in order from the object side to the image side. The second sub-lens group L12 is a focusing group that moves towards the image side when focusing from infinity to close.

[0058] The second lens group L2 and the third lens group L3 are variator groups (V lens groups) that move toward the image side when zooming from the wide-angle end to the telephoto end. The fourth lens group ((N-2) lens group) L4 and the fifth lens group ((N-1) lens group) L5 also move toward the image side when zooming from the wide-angle end to the telephoto end. The aperture diaphragm SP moves together with the fifth lens group L5 when zooming. An optical unit such as an extender lens for focal length conversion may be inserted in the widest air gap in the sixth lens group L6.

[0059] Figure 8(A) shows the longitudinal aberrations (spherical aberration, astigmatism, distortion, and chromatic aberration) of the zoom lens of numerical example 4 at infinity focus and the wide-angle end. Figure 8(B) shows the longitudinal aberrations of the zoom lens of numerical example 4 at infinity focus and the telephoto end. [Examples]

[0060] The zoom lens of Embodiment 5 (Numerical Example 5) shown in Figure 9 is composed of a first lens group L1 with positive refractive power, a second lens group L2 with negative refractive power, a third lens group L3 with negative refractive power, a fourth lens group L4 with negative refractive power, a fifth lens group L5 with positive refractive power, an aperture diaphragm SP, and a sixth lens group L6 with positive refractive power, arranged in order from the object side to the image side. The first lens group L1 does not move for zooming. The second lens group L2, third lens group L3, fourth lens group L4, and fifth lens group L5 constitute three or more movable lens groups that move for zooming. The sixth lens group L6 is the final lens group (Nth lens group) for image formation and does not move for zooming.

[0061] The first lens group L1 consists of a first sub-lens group L11 with negative refractive power, a second sub-lens group L12 with positive refractive power, and a third sub-lens group L13 with positive refractive power, arranged in order from the object side to the image side. The second sub-lens group L12 is a focusing group that moves towards the image side when focusing from infinity to close.

[0062] The second lens group L2 and the third lens group L3 are variator groups (V lens groups) that move toward the image side when zooming from the wide-angle end to the telephoto end. The fourth lens group ((N-2) lens group) L4 and the fifth lens group ((N-1) lens group) L5 also move toward the image side when zooming from the wide-angle end to the telephoto end. An optical unit such as an extender lens for focal length conversion may be inserted in the widest air gap in the sixth lens group L6.

[0063] Figure 10(A) shows the longitudinal aberrations (spherical aberration, astigmatism, distortion, and chromatic aberration) of the zoom lens of numerical example 5 at infinity focus and the wide-angle end. Figure 10(B) shows the longitudinal aberrations of the zoom lens of numerical example 5 at infinity focus and the telephoto end. [Examples]

[0064] The zoom lens of Embodiment 6 (Numerical Example 6) shown in Figure 11 is composed of a first lens group L1 with positive refractive power, a second lens group L2 with positive refractive power, a third lens group L3 with negative refractive power, a fourth lens group L4 with negative refractive power, a fifth lens group L5 with positive refractive power, an aperture diaphragm SP, and a sixth lens group L6 with positive refractive power, arranged in order from the object side to the image side. The first lens group L1 does not move for zooming. The second lens group L2, third lens group L3, fourth lens group L4, and fifth lens group L5 constitute three or more movable lens groups that move for zooming. The sixth lens group L6 is the final lens group (Nth lens group) for image formation and does not move for zooming.

[0065] The first lens group L1 consists of a first sub-lens group L11 with negative refractive power, a second sub-lens group L12 with positive refractive power, and a third sub-lens group L13 with positive refractive power, arranged in order from the object side to the image side. The second sub-lens group L12 is a focusing group that moves towards the image side when focusing from infinity to close.

[0066] The second lens group L2 and the third lens group L3 are variator groups (V lens groups) that move toward the image side when zooming from the wide-angle end to the telephoto end. The fourth lens group ((N-2) lens group) L4 and the fifth lens group ((N-1) lens group) L5 also move toward the image side when zooming from the wide-angle end to the telephoto end. An optical unit such as an extender lens for focal length conversion may be inserted in the widest air gap in the sixth lens group L6.

[0067] Figure 12(A) shows the longitudinal aberrations (spherical aberration, astigmatism, distortion, and chromatic aberration) of the zoom lens of numerical example 6 at infinity focus and the wide-angle end. Figure 12(B) shows the longitudinal aberrations of the zoom lens of numerical example 6 at infinity focus and the telephoto end. [Examples]

[0068] The zoom lens of Embodiment 7 (Numerical Example 7) shown in Figure 13 is composed of a first lens group L1 with positive refractive power, a second lens group L2 with negative refractive power, a third lens group L3 with negative refractive power, a fourth lens group L4 with positive refractive power, an aperture diaphragm SP, and a fifth lens group L5 with positive refractive power, arranged in order from the object side to the image side. The first lens group L1 does not move for zooming. The second lens group L2, the third lens group L3, and the fourth lens group L4 constitute three or more movable lens groups that move for zooming. The fifth lens group L5 is the final lens group (Nth lens group) for image formation and does not move for zooming.

[0069] The first lens group L1 consists of a first sub-lens group L11 with negative refractive power, a second sub-lens group L12 with positive refractive power, and a third sub-lens group L13 with positive refractive power, arranged in order from the object side to the image side. The second sub-lens group L12 is a focusing group that moves towards the image side when focusing from infinity to close.

[0070] The second lens group L2 is a variator group (V lens group) that moves toward the image side when zooming from the wide-angle end to the telephoto end. The third lens group ((N-2) lens group) L3 and the fourth lens group ((N-1) lens group) L4 also move toward the image side when zooming from the wide-angle end to the telephoto end. An optical unit such as an extender lens for focal length conversion may be inserted in the widest air gap in the fifth lens group L5.

[0071] Figure 14(A) shows the longitudinal aberrations (spherical aberration, astigmatism, distortion, and chromatic aberration) of the zoom lens of numerical example 7 at infinity focus and the wide-angle end. Figure 14(B) shows the longitudinal aberrations of the zoom lens of numerical example 7 at infinity focus and the telephoto end.

[0072] Numerical examples 1 to 7 are shown below. In each numerical example, the surface number i indicates the order of the surfaces from the object side, r is the radius of curvature of the i-th surface (mm), and d is the distance on the optical axis between the i-th surface and the (i+1)-th surface (mm). The (variable) of the distance d indicates the distance that changes during zooming, and the distance according to the focal length is shown in a separate table. nd is the absolute refractive index at 1 atmosphere at the d-line of the optical material between the i-th surface and the (i+1)-th surface. νd is the Abbe number of the optical material between the i-th surface and the (i+1)-th surface with respect to the d-line. The Abbe number νd with respect to the d-line is given by Nd, NF, and NC, respectively, when the refractive indices at the d-line, F-line, and C-line are Nd, NF, and NC. It is expressed as νd = (Nd-1) / (NF-NC).

[0073] θgF is the partial dispersion ratio of the optical material between the i-th plane and the (i+1)-th plane with respect to the g-line and the F-line. The partial dispersion ratio of the g-line and the F-line is given by, when the refractive index at the g-line is Ng, θgF = (Ng - NF) / (NF - NC) It is represented as follows.

[0074] Each numerical example also shows the half-angle of view (°) of the zoom lens, in addition to the specifications such as the focal length and F-number of the entire zoom lens system. BF is the back focus, which indicates the air-equivalent distance from the image-side lens surface (final surface) to the image plane of the zoom lens. The total lens length is the distance along the optical axis from the object-side lens surface (frontmost) to the final surface of the zoom lens, plus the back focus. Furthermore, the lens group data shows the focal length of each lens group.

[0075] The asterisk (*) next to the 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 surface vertex in the optical axis direction, H is the height from the optical axis in the direction perpendicular to the optical axis, with the direction of light propagation being positive, R being the radius of paraxial curvature, k (K in the numerical example) being the cone constant, and A3 to A16 being the aspherical coefficients. The cone constant and aspherical coefficients "e±x" are multiplied by 10. ±x It means...

[0076]

number

[0077] [Numerical Example 1] Unit: mm Surface data Face number rd nd νd θgF 1* 42606.960 2.15 1.89190 37.1 0.5780 2 27.149 13.48 3* 58.306 1.50 1.76385 48.5 0.5589 4 36.394 14.57 5 -48.784 1.40 1.90525 35.0 0.5848 6 -139.348 0.20 7 179.434 6.60 1.89286 20.4 0.6393 8 -95.675 3.64 9 1043.755 7.00 1.59522 67.7 0.5442 10* -68.849 4.43 11 1328.657 1.70 2.00069 25.5 0.6136 12 58.203 12.40 1.49700 81.5 0.5375 13 -103.477 0.21 14 -1068.202 14.28 1.43875 94.7 0.5340 15 -39.902 2.00 1.91650 31.6 0.5911 16 -47.581 0.20 17 23517.470 8.27 1.69930 51.1 0.5552 18 -75.192 (variable) 19* -125.330 1.20 1.69930 51.1 0.5552 20 35.256 3.86 21 -220.824 0.82 1.88300 40.8 0.5667 22 25.736 5.81 1.78880 28.4 0.6009 23 -147.111 (variable) 24 -40.955 0.85 1.53775 74.7 0.5392 25 45.600 2.10 1.85478 24.8 0.6122 26 74.105 (Variable) 27* 42.580 5.03 1.73800 32.3 0.5900 28 285.359 (variable) 29 (aperture) ∞ 1.00 30 56.171 1.30 2.05090 26.9 0.6054 31 38.832 6.45 1.53172 48.8 0.5631 32 -318.824 0.42 33 71.419 12.00 1.48749 70.2 0.5300 34 -36.119 1.30 2.00100 29.1 0.5997 35 -113.167 41.07 36 59.085 7.09 1.43875 94.7 0.5340 37 -57.872 6.06 38 -83.704 1.20 2.00100 29.1 0.5997 39 37.639 7.27 1.89286 20.4 0.6393 40 -75.902 0.30 41 48.469 9.55 1.43875 94.7 0.5340 42 -28.911 1.71 2.00100 29.1 0.5997 43 74.397 0.20 44 38.078 7.37 1.48749 70.2 0.5300 45 -77.399 (variable) Image plane ∞ Aspherical data Page 1 K = 0.00000e+00 A 4= 1.84806e-05 A 6= 1.22511e-07 A 8= 1.72935e-09 A10= 5.44089e-12 A12= 3.71223e-15 A14= 1.19089e-19 A16=-3.17244e-23 A 3=-5.50989e-05 A 5=-1.04907e-06 A 7=-1.74321e-08 A 9=-1.16501e-10 A11=-1.75300e-13 A13=-4.44063e-17 A15= 3.53356e-21 Page 3 K = 0.00000e+00 A 4=-1.16790e-05 A 6=-2.08251e-07 A 8=-1.47790e-09 A10=-1.44163e-13 A12= 4.86545e-15 A14= 1.20477e-18 A 3= 4.09795e-05 A 5= 1.39718e-06 A 7= 2.21440e-08 A 9= 5.34933e-11 A11=-9.07942e-14 A13=-1.19736e-16 Page 10 K = 0.00000e+00 A 4= 1.89977e-06 A 6=-8.05631e-10 A 8=-5.52707e-13 A 3= 3.80032e-06 A 5= 1.35474e-08 A 7= 1.53113e-11 Page 19 K = 0.00000e+00 A 4= 4.23146e-06 A 6=-1.89360e-07 A 8=-2.71304e-09 A10=-1.38629e-11 A12=-1.37448e-14 A 3= 1.88284e-06 A 5= 4.88427e-07 A 7= 2.93381e-08 A 9= 2.00605e-10 A11 = 6.65827e-13 Page 27 K = 0.00000e+00 A 4=-2.00990e-06 A 6= 1.28494e-08 A 8= 1.11305e-11 A 3=-1.12208e-06 A 5=-9.53336e-08 A 7=-6.19970e-10 Various data Zoom ratio 4.79 Wide-angle, Medium, Telephoto Focal length 11.48 29.42 55.01 F-numbers: 2.72, 2.73, 3.66 Half-angle (°): 52.20 26.71 15.06 Image height 14.80 14.80 14.80 Lens length 321.01 321.01 321.01 BF 42.48 42.48 42.48 d18 1.09 36.15 51.18 d23 32.77 4.24 5.29 d26 10.43 9.60 1.11 d28 16.22 10.52 2.95 d45 42.48 42.48 42.48 Lens group data Group starting plane focal length 1 1 28.85 2 19 -36.48 3 24 -56.10 4 27 67.22 5 29 71.59 [Numerical Example 2] Unit: mm Surface data Face number rd nd νd θgF 1* 99653.968 2.10 1.83481 42.7 0.5648 2 26.621 13.69 3* 53.277 1.50 1.80400 46.5 0.5577 4 34.126 16.40 5 -49.911 1.40 1.91650 31.6 0.5911 6 -200.550 0.22 7 161.315 8.93 1.80810 22.8 0.6307 8 -83.185 1.20 9 5383.525 7.60 1.59522 67.7 0.5442 10* -71.755 3.97 11 274.397 12.93 1.49700 81.5 0.5375 12 -42.730 1.70 1.95375 32.3 0.5905 13 -68.081 0.20 14 231.453 1.70 2.00100 29.1 0.5997 15 50.576 14.57 1.53775 74.7 0.5392 16 -72.821 0.20 17 1767.052 6.52 1.65412 39.7 0.5737 18 -74.831 (variable) 19 75.379 0.93 1.85150 40.8 0.5695 20 30.722 4.03 21 -362.321 0.85 1.76385 48.5 0.5589 22 20.359 6.19 1.85478 24.8 0.6122 23 -122.445 0.30 24 -87.374 0.75 2.00100 29.1 0.5997 25 71.254 (variable) 26 114.085 0.70 1.83481 42.7 0.5648 27 21.254 4.60 1.78880 28.4 0.6009 28 8996.879 1.94 29 -34.073 0.70 1.90525 35.0 0.5848 30 -357.713 (variable) 31 (aperture) ∞ 4.93 32* 143.199 3.59 1.51633 64.1 0.5353 33 -304.460 0.15 34 48.907 1.10 1.89190 37.1 0.5780 35 37.693 5.95 1.68893 31.1 0.6004 36 -2292.893 (variable) 37 85.702 0.98 1.96300 24.1 0.6212 38 29.559 8.25 1.60311 60.6 0.5415 39 -104.561 41.06 40 79.543 7.29 1.53775 74.7 0.5392 41 -53.892 5.76 42 -78.542 1.00 2.00100 29.1 0.5997 43 45.550 7.00 1.94594 18.0 0.6546 44 -76.212 0.20 45 45.621 8.72 1.49700 81.5 0.5375 46 -37.219 1.00 2.05090 26.9 0.6054 47 41.356 0.20 48 29.384 12.43 1.53172 48.8 0.5631 49 -27.158 1.00 2.00100 29.1 0.5997 50 -58.022 (variable) Image plane ∞ Aspherical data Front page K = 0.00000e+00 A 4=-2.49940e-06 A 6=-4.30470e-07 A 8=-1.39799e-09 A10=-2.33619e-13 A12= 2.12400e-16 A14=-1.50597e-19 A16=-1.63120e-23 A 3= 2.26644e-05 A 5= 3.11265e-06 A 7= 3.18235e-08 A 9= 3.38626e-11 A11=-9.41805e-15 A13= 2.02128e-18 A15= 2.56180e-21 Page 3 K = 0.00000e+00 A 4= 7.41666e-06 A 6= 8.87271e-07 A 8= 9.94141e-09 A10=-6.05462e-12 A12=-6.58359e-14 A14= 8.34199e-17 A16= 2.60180e-20 A 3=-1.78927e-05 A 5=-4.22301e-06 A 7=-1.18514e-07 A 9=-4.12571e-10 A11= 1.59628e-12 A13=-1.09031e-17 A15=-2.57650e-18 Page 10 K = 5.23767e-02 A 4= 1.01819e-06 A 6=-2.33763e-08 A 8=-5.13972e-11 A10= 3.03774e-13 A12= 7.15857e-17 A14= 9.05692e-20 A16= 2.78191e-23 A 3= 2.71548e-07 A 5= 1.38358e-07 A 7= 1.90027e-09 A 9=-3.22019e-12 A11=-8.94836e-15 A13=-9.65298e-20 A15=-3.02326e-21 Page 32 K = 1.17920e+01 A 4=-4.24919e-06 A 6=-1.44582e-08 A 8=-1.89904e-11 A 3= 4.86489e-07 A 5= 1.22033e-07 A 7= 8.46187e-10 Various data Zoom ratio 4.75 Wide-angle, Medium, Telephoto Focal length 11.57 28.77 55.00 F-number 2.73 2.73 3.56 Half-angle (°): 51.98 27.22 15.06 Image height 14.80 14.80 14.80 Lens length 313.08 313.08 313.08 BF 38.32 38.32 38.32 d18 1.00 29.97 42.38 d25 23.21 3.62 2.74 d30 12.43 10.93 1.90 d36 11.67 3.80 1.30 d50 38.32 38.32 38.32 Lens group data Group starting plane focal length 1 1 27.21 2 19 -28.97 3 26 -54.58 4 31 54.45 5 37 80.65 [Numerical Example 3] Unit: mm Surface data Face number rd nd νd θgF 1* 94.027 2.40 1.76385 48.5 0.5589 2 27.780 21.32 3 517.012 1.60 2.00100 29.1 0.5997 4 36.378 16.17 5 -34.012 1.50 1.88300 40.8 0.5667 6 -43.489 1.32 7 221.920 6.61 1.89286 20.4 0.6393 8 -129.479 9.15 9 98.501 10.65 1.61800 63.3 0.5441 10* -70.521 8.43 11 -101.895 3.54 1.49700 81.5 0.5375 12 -71.110 0.20 13 -68.201 1.80 1.76385 48.5 0.5589 14 -60.984 0.20 15 -68.309 1.65 1.95375 32.3 0.5905 16 63.565 10.11 1.43875 94.9 0.5340 17 -52.618 0.20 18 159.070 6.14 1.76385 48.5 0.5589 19 -78.200 (Variable) 20* -858.899 1.20 1.90525 35.0 0.5848 21 45.413 3.85 22 -127.124 0.80 1.59522 67.7 0.5442 23 74.274 3.85 1.85478 24.8 0.6122 24 -75.499 1.01 25 -44.591 0.80 1.76385 48.5 0.5589 26 -117.809 (variable) 27 -63.485 0.80 1.60300 65.4 0.5401 28 46.687 2.21 1.85478 24.8 0.6122 29 94.896 (Variable) 30 (aperture) ∞ 4.11 31* 28.292 6.16 1.58144 40.8 0.5774 32 588.133 0.20 33 67.616 1.00 1.76182 26.5 0.6136 34 37.713 (Variable) 35 653.952 2.82 1.56732 42.8 0.5731 36 -105.975 0.20 37 67.927 1.00 2.05090 26.9 0.6054 38 37.095 4.74 1.53775 74.7 0.5392 39 -4301.074 51.46 40 47.017 7.51 1.55200 70.7 0.5421 41 -101.660 0.40 42 43.718 6.08 1.80810 22.8 0.6307 43 -156.796 1.10 1.88300 40.8 0.5667 44 23.131 1.30 45 23.063 12.76 1.43875 94.7 0.5340 46 -25.599 1.50 2.05090 26.9 0.6054 47 112.290 4.63 48 62.194 8.64 1.48749 70.2 0.5300 49 -37.676 (variable) Image plane ∞ Aspherical data Front page K = 0.00000e+00 A 4= 3.45445e-06 A 6=-1.27211e-09 A 8= 3.91601e-13 A10= 1.13301e-15 A12=-1.39854e-18 A14= 7.08932e-22 A16=-1.23412e-25 Side 10 K = 0.00000e+00 A 4= 1.15440e-06 A 6=-3.35230e-10 A 8= 6.56062e-14 Page 20 K = 0.00000e+00 A 4= 1.51152e-06 A 6=-2.45352e-09 A 8= 3.01831e-11 A10=-1.76333e-13 A12= 3.53546e-16 Page 31 K = 0.00000e+00 A 4=-6.88362e-06 A 6=-1.52829e-09 A 8=-5.34036e-12 Various data Zoom ratio 3.37 Wide-angle, Medium, Telephoto Focal length 11.89 31.51 40.00 F-number 2.90 2.90 3.50 Half-angle (°): 51.23, 25.16, 20.30 Image height 14.80 14.80 14.80 Lens length 329.16 329.16 329.16 BF 37.00 37.00 37.00 d19 1.00 44.56 52.24 d26 39.30 3.58 2.00 d29 8.43 5.29 1.00 d34 10.32 5.62 3.81 d49 37.00 37.00 37.00 Lens group data Group starting plane focal length 1 1 32.71 2 20 -46.54 3 27 -75.91 4 30 84.73 5 35 73.37 [Numerical Example 4] Unit: mm Surface data Face number rd nd νd θgF 1* 10000.000 2.20 1.83481 42.7 0.5648 2 27.261 10.90 3* 43.746 1.55 1.85150 40.8 0.5695 4 29.780 16.94 5 -54.008 1.45 1.95375 32.3 0.5905 6 2340.232 0.20 7 126.680 7.91 1.80810 22.8 0.6307 8 -96.980 1.49 9 337.211 8.36 1.59522 67.7 0.5442 10* -58.106 2.89 11 311.073 13.21 1.43875 94.7 0.5340 12 -37.563 1.60 1.95375 32.3 0.5905 13 -52.130 0.20 14 195.594 1.60 2.00100 29.1 0.5997 15 53.751 14.24 1.43875 94.7 0.5340 16 -56.590 0.20 17 -307.119 4.72 1.76634 35.8 0.5792 18 -68.430 (variable) 19 67.923 0.95 1.80400 46.5 0.5577 20 32.553 2.99 21 -4920.510 0.85 1.76385 48.5 0.5589 22 22.528 5.55 1.78880 28.4 0.6009 23 -75.906 (variable) 24 -70.205 0.75 1.88300 40.8 0.5667 25 50.820 (Variable) 26 -32.470 0.70 1.80400 46.5 0.5577 27 29.951 2.65 1.78880 28.4 0.6009 28 433.737 (variable) 29 (aperture) ∞ 2.04 30 -8622.845 1.00 1.83481 42.7 0.5648 31 54.401 3.85 1.67300 38.3 0.5757 32 -599.694 0.20 33* 36.239 7.96 1.57501 41.5 0.5767 34 -138.526 (variable) 35 263.730 2.31 1.48749 70.2 0.5300 36 -187.158 0.20 37 72.439 1.20 2.00069 25.5 0.6136 38 32.243 8.37 1.51823 58.9 0.5457 39 -113.669 41.34 40 74.294 7.17 1.49700 81.5 0.5375 41 -55.213 0.72 42 -216.396 1.20 2.00100 29.1 0.5997 43 25.638 9.15 1.89286 20.4 0.6393 44 -2098.664 0.20 45 29.296 8.30 1.67300 38.3 0.5757 46 -108.576 1.58 2.00100 29.1 0.5997 47 24.135 0.20 48 21.983 14.17 1.43875 94.7 0.5340 49 -24.253 1.00 2.00100 29.1 0.5997 50 -52.485 (variable) Image plane ∞ Aspherical data Front page K = 0.00000e+00 A 4=-4.39106e-05 A 6=-1.26499e-06 A 8=-3.62054e-09 A10=-6.42274e-13 A12= 3.92028e-16 A14= 6.61559e-20 A16= 7.34553e-24 A 3= 1.49036e-04 A 5= 1.08520e-05 A 7= 8.69501e-08 A 9= 8.38675e-11 A11=-1.50177e-14 A13=-3.97045e-18 A15=-1.20551e-21 3rd page K = 0.00000e+00 A 4= 2.70307e-05 A 6= 9.13168e-07 A 8= 9.74093e-09 A10= 2.53181e-11 A12=-1.22397e-14 A14= 7.66186e-17 A16= 2.34551e-20 A 3=-9.70765e-05 A 5=-6.69142e-06 A 7=-1.01727e-07 A 9=-6.68975e-10 A11=-1.89298e-13 A13=-6.65266e-16 A15=-2.28044e-18 Side 10 K = 0.00000e+00 A 4= 3.66220e-06 A 6= 4.66240e-09 A 8= 4.98196e-13 A 3=-5.18478e-06 A 5=-9.23355e-08 A 7=-9.72622e-11 Page 33 K = 0.00000e+00 A 4=-7.27259e-06 A 6= 2.24551e-09 A 8=-2.15475e-12 Various data Zoom ratio 4.81 Wide-angle, Medium, Telephoto Focal length 11.44 28.81 55.02 F-number 2.73 2.73 3.66 Half-angle (°): 52.30 27.19 15.06 Image height 14.80 14.80 14.80 Lens length 307.39 307.39 307.39 BF 39.12 39.12 39.12 d18 0.98 27.50 38.86 d23 1.00 2.87 4.26 d25 23.60 4.18 4.43 d28 11.96 10.23 2.97 d34 14.47 7.22 1.48 d50 39.12 39.12 39.12 Lens group data Group starting plane focal length 1 1 26.71 2 19 -1804.98 3 24 -33.29 4 26 -36.79 5 29 55.77 6 35 70.65 [Numerical Example 5] Unit: mm Surface data Face number rd nd νd θgF 1* ∞ 2.10 1.83481 42.7 0.5648 2 25.809 14.59 3* 84.172 1.50 1.80400 46.5 0.5577 4 40.603 13.67 5 -44.135 1.40 1.89190 37.1 0.5780 6 -112.235 0.11 7 188.051 7.90 1.80810 22.8 0.6307 8 -76.990 1.45 9 -237.991 7.64 1.49700 81.5 0.5375 10* -49.723 4.09 11 -946.175 10.96 1.48749 70.2 0.5300 12 -40.594 1.75 2.00100 29.1 0.5997 13 -65.641 0.21 14 282.349 1.70 2.00100 29.1 0.5997 15 65.774 15.54 1.43875 94.7 0.5340 16 -56.568 0.19 17 1916.533 7.65 1.76385 48.5 0.5589 18 -74.742 (variable) 19* 205.779 1.20 1.83481 42.7 0.5648 20 27.352 4.21 21 -167.761 0.82 1.83481 42.7 0.5648 22 22.203 6.79 1.78880 28.4 0.6009 23 -63.011 (variable) 24 -32.050 0.82 1.88300 40.8 0.5667 25 -84.151 (variable) 26 -39.149 0.85 1.59522 67.7 0.5442 27 62.164 2.31 1.85478 24.8 0.6122 28 157.587 (variable) 29* 52.222 4.12 1.85150 40.8 0.5695 30 -199.701 (variable) 31 (aperture) ∞ 1.80 32 39.995 6.88 1.51742 52.4 0.5564 33 -146.845 0.23 34 279.585 1.00 2.00100 29.1 0.5997 35 33.798 6.40 1.51633 64.1 0.5353 36 -160.634 0.43 37 -368.954 5.64 1.67270 32.1 0.5988 38 -30.284 1.00 2.00100 29.1 0.5997 39 -80.389 41.40 40 93.888 5.18 1.43875 94.7 0.5340 41 -60.517 0.70 42 57.562 7.87 1.80809 22.7 0.6306 43 -35.852 1.10 1.89190 37.1 0.5780 44 34.242 0.82 45 31.872 13.49 1.43875 94.7 0.5340 46 -23.478 1.10 2.00100 29.1 0.5997 47 171.178 0.13 48 52.667 8.91 1.48749 70.2 0.5300 49 -35.296 (variable) Image plane ∞ Aspherical data Front page K = 0.00000e+00 A 4= 2.01487e-05 A 6= 2.48992e-08 A 8= 2.17115e-11 A10 = -1.96498e-13 A12 = -1.74230e-16 A14 = -3.30200e-19 A16 = -4.27190e-23 A 3 = -4.92267e-05 A 5 = -8.40544e-07 A 7 = -9.83600e-10 A 9 = 2.28192e-12 A11 = 6.34512e-15 A13 = 8.73990e-18 A15 = 6.07222e-21 The 3rd side K = 0.00000e+00 A 4 = -1.79865e-05 A 6 = 1.08737e-07 A 8 = 2.67194e-09 A10 = -2.65927e-10 A12 = -1.84184e-12 A14 = -1.97641e-15 A16 = -1.90543e-19 A 3 = 4.04572e-05 A 5 = 1.49144e-06 A 7 = -5.30553e-08 A 9 = 1.16096e-09 A11 = 2.84179e-11 A13 = 7.62209e-14 A15 = 2.93416e-17 The 10th side K = 0.00000e+00 A 4 = -2.18415e-06 A 6 = -2.03336e-07 A 8 = -1.52986e-09 A10 = 5.10495e-12 A12 = 2.25271e-14 A14 = 9.63941e-19 A16 = -1.87371e-21 A 3 = 9.29120e-06 A 5 = 1.14812e-06 A 7 = 2.31796e-08 A 9 = 2.52009e-11 A11 = -5.09518e-13 A13 = -4.71919e-16 A15 = 1.41597e-19 The 19th side K = 0.00000e+00 A 4 = 5.62296e-06 A 6 = 9.66460e-07 A 8 = 6.14358e-08 A10=-8.91142e-10 A12=-2.54378e-11 A14=-7.20136e-14 A16=-1.75328e-17 A 3=-3.52425e-07 A 5=-1.20759e-06 A 7=-3.48990e-07 A 9=-3.12076e-09 A11= 2.23374e-10 A13= 1.72991e-12 A15= 1.70114e-15 Page 29 K = 0.00000e+00 A 4=-8.28442e-06 A 6=-4.71556e-07 A 8=-5.90301e-09 A10= 3.62432e-12 A12= 6.58822e-14 A14= 8.73138e-17 A16=-5.58289e-21 A 3= 3.07013e-06 A 5= 1.82756e-06 A 7= 7.02954e-08 A 9= 2.30046e-10 A11=-9.68540e-13 A13=-3.02124e-15 A15=-9.83633e-19 Various data Zoom ratio 5.45 Wide-angle, Medium, Telephoto Focal length 10.99 29.91 59.97 F-number 2.99 3.00 4.00 Half-angle (°): 53.39 26.33 13.86 Image height 14.80 14.80 14.80 Lens length 320.99 320.99 320.99 BF 43.15 43.15 43.15 d18 1.26 36.15 51.10 d23 5.70 1.47 3.38 d25 28.22 4.92 3.83 d28 3.82 6.42 0.35 d30 21.20 11.23 1.52 d49 43.15 43.15 43.15 Lens group data Group starting plane focal length 1 1 27.60 2 19 -53.93 3 24 -59.06 4 26 -60.47 5 29 48.98 6 31 74.85 [Numerical Example 6] Unit: mm Surface data Face number rd nd νd θgF 1* 99721.237 2.10 1.88300 40.8 0.5667 2 25.124 15.63 3* 68.600 1.50 1.81600 46.6 0.5568 4 33.546 14.38 5 -45.317 1.40 1.89190 37.1 0.5780 6 -178.717 0.11 7 147.960 9.19 1.80810 22.8 0.6307 8 -69.637 3.61 9 -409.774 8.82 1.49700 81.5 0.5375 10* -47.650 4.23 11 -210.917 8.86 1.49700 81.5 0.5375 12 -39.439 1.75 2.00100 29.1 0.5997 13 -77.835 0.21 14 325.247 1.70 2.00100 29.1 0.5997 15 63.632 12.38 1.49700 81.5 0.5375 16 -88.789 0.19 17 ∞ 8.47 1.76385 48.5 0.5589 18 -64.157 (variable) 19 -402.768 4.00 1.54814 45.8 0.5686 20 -125.167 (variable) 21* 203.099 1.20 1.76385 48.5 0.5589 22 32.045 3.78 23 -462.841 0.82 1.88300 40.8 0.5667 24 21.939 7.59 1.78880 28.4 0.6009 25 -111.087 1.86 26 -33.589 0.82 1.80400 46.5 0.5577 27 -62.504 (variable) 28 -39.248 0.85 1.59522 67.7 0.5442 29 67.288 2.27 1.85478 24.8 0.6122 30 134.040 (variable) 31* 50.024 4.32 1.90525 35.0 0.5848 32 -1067.543 (variable) 33 (aperture) ∞ 1.83 34 48.986 7.26 1.51633 64.1 0.5353 35 -95.477 0.23 36 300.241 1.00 2.00100 29.1 0.5997 37 35.947 4.01 1.48749 70.2 0.5300 38 133.716 0.93 39 138.480 7.51 1.67270 32.1 0.5988 40 -29.019 1.00 2.00100 29.1 0.5997 41 -75.084 34.89 42 90.109 8.59 1.43875 94.7 0.5340 43 -53.209 1.19 44 53.058 6.86 1.80810 22.8 0.6307 45 -50.597 1.10 1.95375 32.3 0.5905 46 31.506 0.92 47 30.981 16.09 1.43875 94.7 0.5340 48 -21.647 1.10 1.90525 35.0 0.5848 49 303.670 0.16 50 71.622 9.78 1.48749 70.2 0.5300 51 -31.057 (variable) Image plane ∞ Aspherical data Front page K = 0.00000e+00 A 4= 2.00578e-05 A 6=-3.49834e-08 A 8=-1.97814e-10 A10=-3.18166e-13 A12=-2.34430e-16 A14=-3.94878e-19 A16=-4.94966e-23 A 3=-2.69692e-05 A 5=-4.49193e-07 A 7= 3.63294e-09 A 9= 8.84344e-12 A11= 8.19638e-15 A13= 1.11763e-17 A15= 7.06579e-21 3rd page K = 0.00000e+00 A 4=-1.88837e-05 A 6= 1.14408e-08 A 8= 1.30608e-09 A10=-2.67806e-10 A12=-1.84918e-12 A14=-1.97831e-15 A16=-1.87551e-19 A 3= 2.30237e-05 A 5= 1.83049e-06 A 7=-3.77502e-08 A 9= 1.22832e-09 A11 = 2.85063e-11 A13 = 7.65091e-14 A15 = 2.91882e-17 The 10th side K = 0.00000e+00 A 4=-9.99055e-07 A 6=-1.14112e-07 A 8=-8.45719e-10 A10 = 4.38289e-12 A12 = 2.18286e-14 A14 = 2.74189e-18 A16=-2.08352e-21 A 3 = 4.92584e-06 A 5 = 6.85638e-07 A 7 = 1.27647e-08 A 9 = 8.15011e-12 A11=-4.50105e-13 A13=-5.24524e-16 A15 = 1.33374e-19 The 21st side K = 0.00000e+00 A 4 = 5.11270e-06 A 6 = 1.27488e-06 A 8 = 6.91406e-08 A10=-9.64538e-10 A12=-2.50957e-11 A14=-6.51372e-14 A16=-1.40914e-17 A 3=-7.60726e-07 A 5=-1.89147e-06 A 7=-4.19029e-07 A 9=-3.20858e-09 A11 = 2.29422e-10 A13 = 1.63798e-12 A15 = 1.45855e-15 The 第31面 K = 0.00000e+00 A 4=-7.29704e-06 A 6=-3.62499e-07 A 8=-3.90225e-09 A10 = 2.84575e-11 A12 = 1.00025e-13 A14 = 4.24406e-17 A16 = 2.35975e-20 A 3 = 3.87591e-06 A 5 = 1.44823e-06 A 7 = 5.36549e-08 A 9=-1.70348e-11 A11 = -2.45064e-12 A13 = -2.20859e-15 A15 = -1.34738e-18 Various data Zoom ratio 3.88 Wide angle, middle, telephoto Focal length 10.30 24.06 39.99 F-number 2.72 2.73 3.12 Half angle of view (°) 55.16 31.60 20.31 Image height 14.80 14.80 14.80 Overall length of lens 321.00 321.00 321.00 BF 43.19 43.19 43.19 d18 0.19 2.23 3.00 d20 0.99 29.75 42.18 d27 27.90 4.02 3.54 d30 4.94 5.49 0.37 d32 17.30 9.83 2.23 d51 43.19 43.19 43.19 Lens group data Group, starting surface, focal length 1 1 32.36 2 19 329.63 3 21 -31.69 4 28 -56.20 5 31 52.88 [[ID= 49]]6 33 72.84 [Numerical example 7] Unit: mm Surface data Surface number, r, d, nd, νd, θgF 1* 107.128 2.15 1.88300 40.8 0.5667 2 26.580 27.77 3* -59.702 1.40 2.00100 29.1 0.5997 4 349.036 0.20 5 208.619 5.83 1.89286 20.4 0.6393 6 -99.748 4.85 7 725.707 7.00 1.59522 67.7 0.5442 8* -71.098 4.61 9 159.628 1.70 2.00100 29.1 0.5997 10 54.415 12.10 1.49700 81.5 0.5375 11 -225.042 0.21 12 -491.474 5.03 1.43875 94.7 0.5340 13 -73.242 2.00 1.84666 23.8 0.6205 14 -89.709 0.20 15 -147.905 4.00 1.83481 42.7 0.5648 16 -91.410 0.20 17 206.052 9.18 1.51823 58.9 0.5457 18 -65.422 (variable) 19* -77.250 1.20 1.89190 37.1 0.5780 20 35.027 3.32 21 -77.045 0.82 1.88300 40.8 0.5667 22 33.725 3.26 1.89286 20.4 0.6393 23 -226.080 (variable) 24 -31.283 0.85 1.49700 81.5 0.5375 25 139.894 1.81 1.85478 24.8 0.6122 26 828.336 (variable) 27* 62.698 8.00 1.88300 40.8 0.5667 28 -105.639 (variable) 29 (aperture) ∞ 1.00 30 109.543 1.30 1.90525 35.0 0.5848 31 47.934 9.55 1.59522 67.7 0.5442 32 -61.090 0.18 33 261.961 12.00 1.53775 74.7 0.5392 34 -34.275 1.30 1.95375 32.3 0.5905 35 -167.219 41.07 36 91.628 7.88 1.43875 94.7 0.5340 37 -46.727 6.60 38 -145.495 1.20 2.00100 29.1 0.5997 39 38.218 7.90 1.89286 20.4 0.6393 40 -89.460 0.30 41 187.115 8.77 1.43875 94.7 0.5340 42 -24.905 1.71 2.00100 29.1 0.5997 43 170.253 0.20 44 47.864 8.27 1.49700 81.5 0.5375 45 -54.028 (variable) Image plane ∞ Aspherical data First surface K = 0.00000e+00 A 4=-2.45588e-05 A 6=-3.67611e-07 A 8= 6.50001e-10 A10= 5.55148e-12 A12= 3.66117e-15 A14= 1.47893e-19 A16=-1.11709e-23 A 3= 6.62720e-05 A 5= 4.37863e-06 A 7= 1.22001e-08 A 9=-9.83386e-11 A11=-1.82674e-13 A13=-4.07328e-17 A15= 1.37079e-21 3rd page K = 0.00000e+00 A 4= 1.95095e-05 A 6= 1.65172e-07 A 8= 1.89745e-10 A10 = 1.56723e-14 A 3=-7.26428e-05 A 5=-2.34782e-06 A 7=-7.20838e-09 A 9=-2.68491e-12 Side 8 K = 0.00000e+00 A 4= 1.08200e-05 A 6= 3.36226e-08 A 8= 5.96039e-12 A 3=-4.57021e-05 A 5=-7.80316e-07 A 7=-7.25175e-10 Page 19 K = 0.00000e+00 A 4=-5.99251e-06 A 6=-6.71902e-06 A 8=-3.40305e-07 A10=-2.73122e-09 A12=-1.98857e-12 A 3= 2.84076e-06 A 5= 1.34577e-05 A 7= 1.91719e-06 A 9= 3.85362e-08 A11 = 1.11133e-10 Page 27 K = 0.00000e+00 A 4=-3.31332e-06 A 6= 1.31899e-08 A 8= 1.05154e-11 A 3=-5.09297e-07 A 5=-8.77617e-08 A 7=-5.90945e-10 Various data Zoom ratio 3.70 Wide-angle, Medium, Telephoto Focal length 13.20 30.03 48.78 F-number 2.73 2.73 3.07 Half-angle (°): 48.27, 26.23, 16.88 Image height 14.80 14.80 14.80 Lens length 312.44 312.44 312.44 BF 40.00 40.00 40.00 d18 1.52 31.94 44.97 d23 37.30 10.62 3.97 d26 0.00 5.70 5.01 d28 16.70 7.27 1.58 d45 40.00 40.00 40.00 Lens group data Group starting plane focal length 1 1 35.51 2 19 -22.26 3 24 -69.63 4 27 45.58 5 29 79.29 Table 1 summarizes the values ​​of equations (1) to (9) in numerical examples 1 to 7. Each zoom lens in the numerical examples satisfies all the conditions of equations (1) to (9).

[0078] [Table 1]

[0079] [Imaging device] Figure 15 schematically shows an imaging device equipped with the zoom lenses of Examples 1 to 7 as the imaging optical system. In Figure 15, 101 is one of the zoom lenses of Examples 1 to 7. 124 is the camera body. 125 is the imaging device configured by attaching the zoom lens 101 to the camera body 124. The zoom lens 101 is detachable from the camera body 124. However, the zoom lens 101 may be integrally provided with the camera body 124.

[0080] The zoom lens 101 has, in order from the object side to the image side, a first lens group F, a zoom section LZ, and an imaging lens group R. The first lens group F includes a focusing lens group that moves during focusing. The zoom section LZ includes at least three lens groups. On the image side of the zoom section LZ are the aperture diaphragm SP, lens group R1, and lens group R2. The imaging device 125 also has an optical unit IE that can be inserted into and removed from the optical path between lens group R1 and lens group R2. By inserting the lens unit IE between lens group R1 and lens group R2, the range of the focal length of the entire zoom lens 101 system can be changed.

[0081] 114 and 115 are drive mechanisms that move the first lens group F and the lens group included in the zoom section LZ along the optical axis, respectively. 116 to 118 are motors that drive the drive mechanisms 114 and 115 and the aperture diaphragm SP, respectively. 119 to 121 are detection units that detect the position of the first lens group F and the lens group included in the zoom section LZ on the optical axis, and detect the aperture diameter of the aperture diaphragm SP, respectively.

[0082] In the camera body 124, 109 is a glass block such as an optical filter, and 110 is an image sensor that captures the subject image (i.e., the subject through the zoom lens 101) formed by the zoom lens 101. The image sensor 110 is composed of photoelectric conversion elements such as a CCD sensor or a CMOS sensor. 111 and 122 are the camera CPU, which is the processing unit in the camera body 124, and the lens CPU, which is the processing unit in the zoom lens 101, respectively.

[0083] The above embodiments include the following configuration. (Composition 1) A zoom lens comprising multiple lens groups, The aforementioned group of lenses consists of a first lens group with positive refractive power that does not move for zooming, arranged sequentially from the object side to the image side, three or more moving lens groups that move for zooming, and a final Nth lens group with positive refractive power, wherein the spacing between adjacent lens groups changes during zooming. The three or more moving lens groups include a (N-1) lens group with positive refractive power, a (N-2) lens group with negative refractive power, and one or more V lens groups, arranged in order from the image side to the object side. The first lens group includes a focus group that moves for focusing, The aforementioned (N-1) lens group is located closer to the image at the telephoto end than it is at the wide-angle end. The aforementioned N lens group is composed of a front sub-lens group and a rear sub-lens group arranged in order from the object side with the widest air gap between them. Let f1 be the focal length of the first lens group, fVi be the focal length of the i-th moving lens group from the object side among the one or more V lens groups, and let Σ(f1 / fVi) be the sum of f1 / fVi, let β(N-1)w be the lateral magnification at the wide-angle end of the (N-1) lens group, LE be the length along the optical axis of the widest air gap in the N lens group, LR be the length along the optical axis from the object-side surface of the N lens group to the image-side surface of the N lens group, and let βrr be the lateral magnification at the wide-angle end of the rear sub-lens group. -2.2≦Σ(f1 / fVi)≦-0.4 2.0 ≤ β(N-1)w ≤ 18.5 0.3 ≤ LE / LR ≤ 0.7 -0.8 ≤ βrr ≤ 0.8 A zoom lens characterized by satisfying the following conditions. (Configuration 2) When the lateral magnification of the (N-1) lens group at the telephoto end is β(N-1)t, 1.0 ≤ β(N-1)t / β(N-1)w ≤ 1.2 A zoom lens according to configuration 1, characterized by satisfying the following conditions. (Composition 3) When bok1 is the distance along the optical axis from the image-side surface of the first lens group to the rear principal point of the first lens group, 2.0 ≤ (f1 + bok1) / f1 ≤ 5.0 A zoom lens according to configuration 1 or 2, characterized by satisfying the following conditions. (Composition 4) Let f(N-1) be the focal length of the aforementioned (N-1) lens group, and let Σ(f1 / fVi) be the sum of f(N-1) / fVi. -3.0 ≤ Σ(f(N-1) / fVi) ≤ -0.5 A zoom lens according to any one of configurations 1 to 3, characterized by satisfying the following conditions. (Composition 5) The aforementioned one or more V lens groups include one or more lens groups with negative refractive power, When Lm is the amount of movement from the object side to the image side during zooming from the wide-angle end to the telephoto end of the lens group with the largest negative refractive power among the one or more lens groups with negative refractive power, and L is the length along the optical axis from the object-side surface of the first lens group to the image-side surface of the N lens group, 0.0 <Lm / L≦0.3 A zoom lens according to any one of configurations 1 to 4, characterized by satisfying the following conditions. (Composition 6) When the focal length of the zoom lens at its wide-angle end is denoted as fw, 1.0 ≤ f1 / fw ≤ 10.0 A zoom lens according to any one of configurations 1 to 5, characterized by satisfying the following conditions. (Composition 7) The zoom lens according to any one of configurations 1 to 6, characterized in that the first lens group comprises a first sub-lens group with negative refractive power that does not move for focusing and is positioned on the object side of the focus group that moves for focusing, a second sub-lens group with positive refractive power as the focus group, and a third sub-lens group with positive refractive power that does not move for focusing and is positioned on the image side of the focus group. (Composition 8) The zoom lens according to any one of configurations 1 to 7, characterized in that the first lens group is composed of six or more lenses. (Composition 9) The (N-1) lens group is characterized by moving monotonically toward the image side when zooming from the wide-angle end to the telephoto end, as described in any one of configurations 1 to 8. (Composition 10) The zoom lens according to any one of configurations 1 to 9, characterized in that the plurality of lens groups are composed of the first lens group, the second lens group with negative refractive power, the third lens group with negative refractive power, the fourth lens group with positive refractive power, and the fifth lens group which is the final lens group, arranged in order from the object side to the image side. (Composition 11) The zoom lens according to any one of configurations 1 to 9, characterized in that the plurality of lens groups are composed of a first lens group, a second lens group with negative refractive power, a third lens group with negative refractive power, a fourth lens group with negative refractive power, a fifth lens group with positive refractive power, and a sixth lens group which is the final lens group, arranged in order from the object side to the image side. (Composition 12) The zoom lens according to any one of configurations 1 to 9, characterized in that the plurality of lens groups are composed of a first lens group, a second lens group with positive refractive power, a third lens group with negative refractive power, a fourth lens group with negative refractive power, a fifth lens group with positive refractive power, and a sixth lens group which is the final lens group, arranged in order from the object side to the image side. (Composition 13) A zoom lens comprising multiple lens groups, The aforementioned group of lenses consists of a first lens group with positive refractive power that does not move for zooming, arranged sequentially from the object side to the image side, three or more moving lens groups that move for zooming, and a final Nth lens group with positive refractive power, wherein the spacing between adjacent lens groups changes during zooming. The three or more moving lens groups include a (N-1) lens group with positive refractive power, a (N-2) lens group with negative refractive power, and one or more V lens groups, arranged in order from the image side to the object side. The first lens group includes a focus group that moves for focusing, The aforementioned (N-1) lens group is located closer to the image at the telephoto end than it is at the wide-angle end. The aforementioned N lens group is composed of a front sub-lens group and a rear sub-lens group arranged in order from the object side with the widest air gap between them. When the lateral magnification of the (N-1) lens group at the wide-angle end is β(N-1)w, 2.0 ≤ β(N-1)w ≤ 18.5 A zoom lens characterized by satisfying the following conditions. (Composition 14) A zoom lens as described in any one of configurations 1 to 13, An imaging device characterized by having an image sensor that captures an image of a subject through the zoom lens.

[0084] The embodiments described above are merely representative examples, and various modifications and changes can be made to each embodiment when implementing the present invention. [Explanation of Symbols]

[0085] L1 First lens group L2 Second lens group L3 Third lens group L4 4th lens group L5 5th lens group L6 6th lens group L12 Second sub-lens group (focusing group)

Claims

1. A zoom lens comprising multiple lens groups, The aforementioned group of lenses consists of a first lens group with positive refractive power that does not move for zooming, arranged sequentially from the object side to the image side, three or more moving lens groups that move for zooming, and a final Nth lens group with positive refractive power, wherein the spacing between adjacent lens groups changes during zooming. The three or more moving lens groups include a (N-1) lens group with positive refractive power, a (N-2) lens group with negative refractive power, and one or more V lens groups, arranged in order from the image side to the object side. The first lens group includes a focus group that moves for focusing, The (N-1) lens group is positioned closer to the image at the telephoto end than at the wide-angle end. The aforementioned N lens group is composed of a front sub-lens group and a rear sub-lens group arranged in order from the object side with the widest air gap between them. Let f1 be the focal length of the first lens group, fVi be the focal length of the i-th moving lens group from the object side among the one or more V lens groups, and let Σ(f1 / fVi) be the sum of f1 / fVi, let β(N-1)w be the lateral magnification at the wide-angle end of the (N-1) lens group, let LE be the length along the optical axis of the widest air gap in the N lens group, let LR be the length along the optical axis from the object-side surface of the N lens group to the image-side surface of the N lens group, and let βrr be the lateral magnification at the wide-angle end of the rear sub-lens group. -2.2≦Σ(f1 / fVi)≦-0.4 2.0≦β(N-1)w≦18.5 0.3 ≤ LE / LR ≤ 0.7 -0.8 ≤ βrr ≤ 0.8 A zoom lens characterized by satisfying the following conditions.

2. When the lateral magnification of the (N-1) lens group at the telephoto end is β(N-1)t, 1.0≦β(N-1)t / β(N-1)w≦1.2 The zoom lens according to claim 1, characterized by satisfying the following conditions.

3. When bok1 is the distance along the optical axis from the image-side surface of the first lens group to the rear principal point of the first lens group, 2.0≦(f1+bok1) / f1≦5.0 The zoom lens according to claim 1, characterized by satisfying the following conditions.

4. Let f(N-1) be the focal length of the (N-1) lens group, and let Σ(f1 / fVi) be the sum of f(N-1) / fVi. -3.0≦Σ(f(N-1) / fVi)≦-0.5 The zoom lens according to claim 1, characterized by satisfying the following conditions.

5. The aforementioned one or more V-lens groups include one or more lens groups with negative refractive power, When Lm is the amount of movement from the object side to the image side during zooming from the wide-angle end to the telephoto end of the lens group with the largest negative refractive power among the one or more lens groups with negative refractive power, and L is the length along the optical axis from the object-side surface of the first lens group to the image-side surface of the N lens group, 0.0<Lm / L≦0.3 The zoom lens according to claim 1, characterized by satisfying the following conditions.

6. When the focal length of the zoom lens at its wide-angle end is fw, 1.0 ≤ f1 / fw ≤ 10.0 The zoom lens according to claim 1, characterized by satisfying the following conditions.

7. The zoom lens according to claim 1, characterized in that the first lens group comprises a first sub-lens group with negative refractive power that does not move for focusing and is positioned on the object side of the focus group that moves for focusing, a second sub-lens group with positive refractive power that serves as the focus group, and a third sub-lens group with positive refractive power that does not move for focusing and is positioned on the image side of the focus group.

8. The zoom lens according to claim 1, characterized in that the first lens group is composed of six or more lenses.

9. The zoom lens according to claim 1, characterized in that the (N-1) lens group moves monotonically toward the image side when zooming from the wide-angle end to the telephoto end.

10. The zoom lens according to claim 1, characterized in that the plurality of lens groups are composed of a first lens group, a second lens group with negative refractive power, a third lens group with negative refractive power, a fourth lens group with positive refractive power, and a fifth lens group which is the final lens group, arranged in order from the object side to the image side.

11. The zoom lens according to claim 1, characterized in that the plurality of lens groups are composed of a first lens group, a second lens group with negative refractive power, a third lens group with negative refractive power, a fourth lens group with negative refractive power, a fifth lens group with positive refractive power, and a sixth lens group which is the final lens group, arranged in order from the object side to the image side.

12. The zoom lens according to claim 1, characterized in that the plurality of lens groups are composed of a first lens group, a second lens group with positive refractive power, a third lens group with negative refractive power, a fourth lens group with negative refractive power, a fifth lens group with positive refractive power, and a sixth lens group which is the final lens group, arranged in order from the object side to the image side.

13. A zoom lens comprising multiple lens groups, The aforementioned group of lenses consists of a first lens group with positive refractive power that does not move for zooming, arranged sequentially from the object side to the image side, three or more moving lens groups that move for zooming, and a final Nth lens group with positive refractive power, wherein the spacing between adjacent lens groups changes during zooming. The three or more moving lens groups include a (N-1) lens group with positive refractive power, a (N-2) lens group with negative refractive power, and one or more V lens groups, arranged in order from the image side to the object side. The first lens group includes a focus group that moves for focusing, The (N-1) lens group is positioned closer to the image at the telephoto end than at the wide-angle end. The aforementioned N lens group is composed of a front sub-lens group and a rear sub-lens group arranged in order from the object side with the widest air gap between them. When the lateral magnification of the (N-1) lens group at the wide-angle end is β(N-1)w, 2.0≦β(N-1)w≦18.5 A zoom lens characterized by satisfying the following conditions.

14. A zoom lens according to any one of claims 1 to 13, An imaging device characterized by having an image sensor that captures an image of a subject through the zoom lens.

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