Zoom lens and imaging device

Abstract

To provide a zoom lens capable of achieving high-definition and high-speed zoom operation while having a small size, a high variable power ratio and a large aperture ratio.SOLUTION: A zoom lens (L0a) consists of a first lens group (L1) having positive refractive power, a second lens group (L2) having negative refractive power and a subsequent group (LR) including at least four lens groups moving when zooming in this order from the object side to the image side. An interval between the lens groups adjacent to each other is changed when zooming. The first lens group avoids movement to an image surface when zooming and focusing. A distance Lw on the optical axis from a surface peak point position of the surface on the most object side in the zoom lens at a wide angle end to an image surface, a focal distance fw of the zoom lens at the wide angle end, a distance T2 on the optical axis from a surface peak point position of the surface on the most object side in the second lens group to a surface peak point position of the surface on the most image side and a focal distance f2 of the second lens group satisfy a predetermined conditional expression.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a zoom lens and an imaging apparatus. [Background technology]

[0002] There is a demand for a zoom lens used in an imaging device that is small, lightweight, and has high optical performance that satisfactorily corrects various aberrations such as chromatic aberration. There is also a demand for a zoom lens that has a short focal length at the wide-angle end, a large variable magnification ratio, a small F-number, a large aperture ratio, and is easy to manufacture. There is also a demand for a zoom lens that allows high-speed zoom operation. Patent Document 1 discloses a zoom lens that is composed of, in order from the object side to the image side, a lens group with positive refractive power, a lens group with negative refractive power, and a rear group having multiple lens groups. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-134807 A Summary of the Invention [Problem to be solved by the invention]

[0004] With the zoom lens disclosed in Patent Document 1, it is difficult to achieve high image quality and high-speed zoom operation while being compact, having a high zoom ratio, and a large aperture ratio.

[0005] SUMMARY OF THE PRESENT EMBODIMENTS An object of the present invention is to provide a zoom lens that is compact, has a high zoom ratio, and a large aperture ratio, while achieving high image quality and high-speed zoom operation. [Means for solving the problem]

[0006] A zoom lens according to one aspect of the present invention comprises, in order from the object side to the image side, a first lens group with positive refractive power, a second lens group with negative refractive power, and a subsequent group having at least four lens groups that move during zooming, wherein the spacing between adjacent lens groups changes during zooming, and the first lens group does not move relative to an image plane during zooming and focusing, and when the distance on the optical axis from the surface vertex position of the surface closest to the object in the zoom lens at the wide-angle end to the image plane is Lw, the focal length of the zoom lens at the wide-angle end is fw, the distance on the optical axis from the surface vertex position of the surface closest to the object in the second lens group to the surface vertex position of the surface closest to the image plane is T2, and the focal length of the second lens group is f2, 7.5 <Lw / fw<15.0 0.20 <T2 / |f2|<0.85 The following condition is satisfied.

[0007] Other objects and features of the present invention are illustrated in the following examples. Effect of the Invention

[0008] According to the present invention, it is possible to provide a zoom lens that is small in size, has a high zoom ratio and a large aperture ratio, yet achieves high image quality and high-speed zoom operation. [Brief description of the drawings]

[0009] [Figure 1] 1 is a cross-sectional view of a zoom lens according to a first embodiment. [Diagram 2] 4A to 4C are aberration diagrams of the zoom lens in Example 1. [Diagram 3] FIG. 11 is a cross-sectional view of a zoom lens according to a second embodiment. [Figure 4] 8A to 8C are aberration diagrams of the zoom lens in Example 2. [Diagram 5] FIG. 11 is a cross-sectional view of a zoom lens according to a third embodiment. [Figure 6] 11A to 11C are aberration diagrams of the zoom lens in Example 3. [Figure 7]FIG. 11 is a cross-sectional view of a zoom lens according to a fourth embodiment. [Figure 8] 11A to 11C are aberration diagrams of the zoom lens in Example 4. [Figure 9] FIG. 13 is a cross-sectional view of a zoom lens according to a fifth embodiment. [Figure 10] 13A to 13C are aberration diagrams of the zoom lens in Example 5. [Figure 11] 1 is a schematic diagram of an imaging device equipped with a zoom lens in each embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0011] In order to realize high-speed zoom operation, it is preferable to reduce the mass and the movement amount of the lens group that moves during zooming. In order to suppress the mass of the moving lens group, it is preferable to reduce the number of lenses that make up the moving lens group. However, if the number of lenses that make up the moving lens group is reduced, it becomes difficult to correct aberrations, and it becomes difficult to achieve high image quality. In addition, if the movement amount of the moving lens group is reduced, it becomes difficult to achieve high zoom ratio. In addition, if the refractive power of the lens group that constitutes the zoom lens is strengthened in order to reduce the movement amount of the moving lens group, it becomes difficult to correct aberrations, and it becomes difficult to achieve high image quality. Therefore, in order to obtain a zoom lens that is small, has a high zoom ratio, and has a large aperture ratio, yet achieves high image quality and high-speed zoom operation, it is important to appropriately set the arrangement of the lenses and lens groups that constitute the zoom lens.

[0012] The zoom lens of each embodiment is composed of, in order from the object side to the image side, a first lens group L1 with positive refractive power, a second lens group L2 with negative refractive power, and a trailing group LR having at least four lens groups that move during zooming. During zooming, the interval between adjacent lens groups (air interval along the optical axis OA) changes. During zooming and focusing, the first lens group L1 does not move relative to the image plane. Since a zoom lens with a high zoom ratio and a large aperture ratio tends to have a large front lens diameter and a large mass, fixing the first lens group L1 relative to the image plane can facilitate high-speed zooming. Furthermore, by moving the multiple lens groups while changing the interval, various aberrations during zooming, particularly zoom fluctuations in lateral chromatic aberration and astigmatism, are well corrected.

[0013] In the zoom lens of each embodiment, the following conditional expressions (1) and (2) are satisfied.

[0014] 7.50 <Lw / fw<15.00 ···(1) 0.20 <T2 / |f2|<0.85 ···(2) Here, Lw is the distance on the optical axis from the vertex position of the surface closest to the object in the zoom lens at the wide-angle end to the image plane, fw is the focal length of the zoom lens (entire system) at the wide-angle end, T2 is the distance on the optical axis from the vertex position of the surface closest to the object in the second lens group L2 to the vertex position of the surface closest to the image plane, and f2 is the focal length of the second lens group L2.

[0015] Conditional formula (1) specifies the relationship between the distance on the optical axis from the vertex of the surface closest to the object at the wide-angle end to the image plane and the focal length of the zoom lens (entire system) at the wide-angle end. If the upper limit of conditional formula (1) is exceeded, the lens diameter and mass of the second lens group L2 become large, making it difficult to achieve high-speed zoom operation, which is undesirable. On the other hand, if the lower limit of conditional formula (1) is exceeded, the refractive power of each lens group becomes too strong, making it difficult to correct various aberrations, particularly spherical aberration and astigmatism, which is undesirable.

[0016] Conditional formula (2) defines the relationship between the axial thickness of the second lens group L2 and the focal length of the second lens group L2. If the thickness of the second lens group L2 exceeds the upper limit of conditional formula (2), the mass of the second lens group L2 increases, making it difficult to achieve high-speed zooming, which is undesirable. On the other hand, if the thickness of the second lens group L2 decreases beyond the lower limit of conditional formula (2), it becomes difficult to suppress the aberrations generated in the second lens group L2, and the correction of various aberrations, particularly the zoom fluctuation of spherical aberration and astigmatism, becomes large, which is undesirable.

[0017] In each embodiment, it is preferable that the numerical range of at least one of conditional expressions (1) and (2) is set as shown in the following conditional expressions (1a) and (2a), respectively.

[0018] 8.02 <Lw / fw<12.16 ···(1a) 0.38 <T2 / f2<0.84 ···(2a) In each embodiment, it is more preferable that the numerical range of at least one of conditional expressions (1) and (2) is set as shown in the following conditional expressions (1b) and (2b), respectively. 8.28 <Lw / fw<10.74 ···(1b) 0.47 <T2 / f2<0.83 ···(2b) Next, a preferred configuration of the zoom lens in each embodiment will be described.

[0019] In each embodiment, the first lens group L1 preferably has a lens (first lens) L11 with negative refractive power closest to the object side, which makes it easy to reduce the diameter of the front lens, facilitating size reduction.

[0020] In each embodiment, the rear group LR has, in order from the object side to the image side, a third lens group L3 with positive refractive power and a fourth lens group L4 with positive refractive power. By changing the interval between the lens groups with positive refractive power, zoom fluctuations of astigmatism can be suppressed, and optical image quality can be easily improved. In addition, by arranging multiple lens groups with positive refractive power, the height of the light beam incident on the lens group arranged on the image side of the fourth lens group L4 can be reduced, and the lens group arranged on the image side of the fourth lens group L4 can be easily made smaller in diameter and size.

[0021] In each embodiment, preferably, when focusing from infinity to a close distance (during focusing), a lens or lens group arranged on the image side of the fourth lens group L4 moves. By configuring the lens group with a large diameter arranged on the object side to be fixed during focusing and the lens or lens group with a small diameter arranged on the image side of the fourth lens group L4 to perform focusing, it becomes easy to reduce the weight of the focus lens group and simplify the drive mechanism. This makes it easy to make the device compact.

[0022] In each embodiment, the first lens unit L1 has at least three lenses with positive refractive power, which makes it easy to achieve both high zoom ratio and high performance.

[0023] In each embodiment, the second lens group L2 includes, in order from the object side to the image side, a lens (second lens) with negative refractive power, a lens with negative refractive power, a lens with negative refractive power, and a lens with positive refractive power. By disposing the negative lens on the object side of the second lens group L2, it becomes easy to achieve both a wide angle and a small front lens diameter.

[0024] In each embodiment, it is preferable to satisfy at least one of the following conditional expressions (3) to (15).

[0025] 0.20 <skw / fw<1.50 ···(3) 1.50<|f1 / f2|<7.70 (4) 0.60 <M2 / fw<3.20 ···(5) <h2 style=";text-align:left;direction:ltr">-2.00<β2t<-0.30 ···(6)<h2 style=";text-align:left;direction:ltr"> <h2 style=";text-align:left;direction:ltr"> 0.10 <T1 / f1<0.70 ···(7) <h2 style=";text-align:left;direction:ltr"> <h2 style=";text-align:left;direction:ltr"> 0.40<|f11 / f1|<2.20 ···(8)<h2 style=";text-align:left;direction:ltr"> <h2 style=";text-align:left;direction:ltr"> -2.00<(r112+r111) / (r112-r111)<-0.20 ···(9)<h2 style=";text-align:left;direction:ltr"> <h2 style=";text-align:left;direction:ltr"> 0.10 <MR / ft<0.50 ···(10) <h2 style=";text-align:left;direction:ltr"> <h2 style=";text-align:left;direction:ltr"> 2.00 <f3 / fw<11.00 ···(11) <h2 style=";text-align:left;direction:ltr"> <h2 style=";text-align:left;direction:ltr"> 0.70 <f4 / fw<6.70 ···(12) <h2 style=";text-align:left;direction:ltr"> <h2 style=";text-align:left;direction:ltr"> 0.40<(D34w-D34t) / fw<1.80 ···(13)<h2 style=";text-align:left;direction:ltr"> <h2 style=";text-align:left;direction:ltr"> 0.60<|f21 / f2|<3.00 ···(14)<h2 style=";text-align:left;direction:ltr"> <h2 style=";text-align:left;direction:ltr"> -2.60<(r212+r211) / (r212-r211)<-0.50 ···(15)<h2 style=";text-align:left;direction:ltr"> Here, skw is the distance on the optical axis from the vertex position of the surface closest to the image side in the zoom lens at the wide-angle end to the image surface (back focus). f1 is the focal length of the first lens group L1. f2 is the focal length of the second lens group L2. M2 is the absolute value of the movement amount of the second lens group L2 during zooming from the wide-angle end to the telephoto end. β2T is the lateral magnification of the second lens group L2 at the telephoto end. T1 is the distance on the optical axis from the vertex position of the surface closest to the object side in the first lens group L1 to the vertex position of the surface closest to the image side. f11 is the focal length of the lens (first lens) L11. r111 is the radius of curvature of the surface closest to the object side in the lens L11, and r112 is the radius of curvature of the surface closest to the image side in the lens L11. MR is the maximum absolute value of the movement amount of the lens groups constituting the subsequent group LR during zooming from the wide-angle end to the telephoto end. ft is the focal length of the zoom lens (whole system) at the telephoto end. f3 is the focal length of the third lens group L3, and f4 is the focal length of the fourth lens group L4. D34w is the distance on the optical axis from the vertex position of the surface closest to the image in the third lens group L3 to the vertex position of the surface closest to the object in the fourth lens group L4 at the wide-angle end. D34t is the distance on the optical axis from the vertex position of the surface closest to the image in the third lens group L3 to the vertex position of the surface closest to the object in the fourth lens group L4 at the telephoto end. f21 is the focal length of the lens (second lens) L21. r211 is the radius of curvature of the surface closest to the object in the lens L21, and r212 is the radius of curvature of the surface closest to the image in the lens L21.

[0026] Conditional formula (3) specifies the relationship between the back focus at the wide-angle end and the focal length of the zoom lens (entire system). If the back focus is long beyond the upper limit of conditional formula (3), the diameter of the front lens increases, resulting in a large size, which is not preferable. On the other hand, if the back focus is short beyond the lower limit of conditional formula (3), the diameter of the lenses constituting the rear group LR increases, and the mass of the lenses constituting the rear group LR increases, which is not preferable, making it difficult to achieve high-speed zoom operation.

[0027] Conditional formula (4) defines the relationship between the focal length of the first lens group L1 and the focal length of the second lens group L2. If the focal length of the first lens group L1 increases beyond the upper limit of conditional formula (4), the size of the lens increases, which is not preferable. On the other hand, if the focal length of the first lens group L1 decreases beyond the lower limit of conditional formula (4), it becomes difficult to correct various aberrations, particularly spherical aberration and lateral chromatic aberration at the telephoto end, which is not preferable.

[0028] Conditional formula (5) defines the relationship between the amount of movement of the second lens group L2 and the focal length at the wide-angle end. If the amount of movement of the second lens group L2 increases beyond the upper limit of conditional formula (5), it becomes difficult to realize high-speed zooming, which is undesirable. On the other hand, if the amount of movement of the second lens group L2 decreases beyond the lower limit of conditional formula (5), it becomes difficult to realize a high zoom ratio, which is undesirable.

[0029] Conditional formula (6) specifies the lateral magnification of the second lens group L2 at the telephoto end. If the absolute value of the lateral magnification of the second lens group L2 at the telephoto end becomes small beyond the upper limit of conditional formula (6), it becomes difficult to achieve a high zoom ratio, which is not preferable. On the other hand, if the absolute value of the lateral magnification of the second lens group L2 becomes large beyond the lower limit of conditional formula (6), the second lens group L2's share of the zoom ratio becomes large. As a result, it becomes difficult to correct aberrations occurring in the second lens group L2, and it becomes particularly difficult to suppress zoom fluctuations in spherical aberration and astigmatism, which is not preferable.

[0030] Conditional formula (7) defines the relationship between the thickness of the first lens group L1 and the focal length. If the thickness of the first lens group L1 increases beyond the upper limit of conditional formula (7), the front lens diameter increases, which is undesirable. On the other hand, if the thickness of the first lens group L1 decreases beyond the lower limit of conditional formula (7), it becomes difficult to correct aberrations occurring in the first lens group L1, and it becomes particularly difficult to correct spherical aberration and chromatic aberration of magnification at the telephoto end, which is undesirable.

[0031] Conditional formula (8) defines the relationship between the focal length of lens L11 and the focal length of the first lens group L1. If the absolute value of the focal length of lens L11 increases beyond the upper limit of conditional formula (8), the front lens diameter increases, which is not preferable. On the other hand, if the absolute value of the focal length of lens L11 decreases beyond the lower limit of conditional formula (8), it becomes difficult to correct aberrations generated by lens L11, and it becomes particularly difficult to correct distortion and coma at the wide-angle end, which is not preferable.

[0032] Conditional expression (9) defines the relationship between the radius of curvature of the object-side surface and the image-side surface of lens L11. If the upper limit of conditional expression (9) is exceeded, it is undesirable because it becomes difficult to correct distortion. On the other hand, if the lower limit of conditional expression (9) is exceeded, it is undesirable because the front lens diameter increases and becomes large.

[0033] Conditional formula (10) defines the relationship between the maximum absolute value of the movement amount of the lenses constituting the rear group LR and the focal length of the focus lens (whole system) at the telephoto end. If the maximum absolute value of the movement amount of the lenses constituting the rear group LR becomes large beyond the upper limit of conditional formula (10), it becomes difficult to realize high-speed zoom operation, which is undesirable. On the other hand, if the maximum absolute value of the movement amount of the lenses constituting the rear group LR becomes small beyond the lower limit of conditional formula (10), it becomes difficult to achieve a high zoom ratio, which is undesirable.

[0034] Conditional expression (11) defines the relationship between the focal length of the third lens group L3 and the focal length of the zoom lens (entire system) at the wide-angle end. If the focal length of the third lens group L3 increases beyond the upper limit of conditional expression (11), the diameter of the lens group arranged on the image side of the third lens group L3 increases, which is undesirable because the size of the lens group increases. On the other hand, if the focal length of the third lens group L3 decreases beyond the lower limit of conditional expression (11), it becomes difficult to correct aberrations generated in the third lens group L3, and it becomes difficult to correct various aberrations, particularly spherical aberration and axial chromatic aberration at the telephoto end, which is undesirable.

[0035] Conditional expression (12) defines the relationship between the focal length of the fourth lens group L4 and the focal length of the zoom lens (entire system) at the wide-angle end. If the focal length of the fourth lens group L4 increases beyond the upper limit of conditional expression (12), the diameter of the lens group arranged closer to the image side than the fourth lens group L4 increases, resulting in a large size, which is undesirable. On the other hand, if the focal length of the fourth lens group L4 decreases beyond the lower limit of conditional expression (12), it becomes difficult to correct aberrations generated by the fourth lens group L4, and it becomes difficult to correct various aberrations, particularly spherical aberration and astigmatism at the telephoto end and coma aberration at the wide-angle end, which is undesirable.

[0036] Conditional expression (13) defines the relationship between the distance (air distance) between the third lens group L3 and the fourth lens group L4 at the wide-angle end and the telephoto end and the focal length of the zoom lens (total system) at the wide-angle end. If the change in the distance becomes large beyond the upper limit of conditional expression (13), the amount of movement of the fourth lens group L4 becomes large, which is undesirable as it becomes difficult to realize high-speed zoom operation. On the other hand, if the change in the distance becomes small beyond the lower limit of conditional expression (13), the zoom fluctuation of astigmatism becomes large, which is undesirable as it becomes difficult to realize high image quality.

[0037] Conditional expression (14) defines the relationship between the focal length of lens L21 and the focal length of the second lens group L2. If the absolute value of the focal length of lens L21 becomes large beyond the upper limit of conditional expression (14), the front lens diameter increases, which is undesirable because it makes the lens larger. On the other hand, if the absolute value of the focal length of lens L21 becomes small beyond the lower limit of conditional expression (14), it becomes difficult to correct various aberrations, particularly distortion and lateral chromatic aberration at the wide-angle end, which is undesirable.

[0038] Conditional expression (15) defines the relationship between the radius of curvature of the object-side surface of lens L21 and the radius of curvature of the image-side surface. If the upper limit of conditional expression (15) is exceeded, it is undesirable because it becomes difficult to correct distortion. On the other hand, if the lower limit of conditional expression (15) is exceeded, it is undesirable because the front lens diameter increases and becomes large.

[0039] In each embodiment, it is more preferable that the numerical range of at least one of conditional expressions (3) to (15) is set as in the following conditional expressions (1a) to (15a), respectively.

[0040] 0.33 <skw / fw<1.13 ···(3a) 2.25<|f1 / f2|<5.79 (4a) 0.90 <M2 / fw<2.41 ···(5a) -1.05<β2t<-0.60 (6a) 0.17 <T1 / f1<0.53 ···(7a) 0.60<|f11 / f1|<1.65 (8a) -1.50<(r112+r111) / (r112-r111)<-0.21 ···(9a) 0.17 <MR / ft<0.38 ···(10a) 2.97 <f3 / fw<8.26 ···(11a) 1.04 <f4 / fw<5.04 ···(12a) 0.58<(D34w-D34t) / fw<1.35 (13a) 0.94<|f21 / f2|<2.24 (14a) -1.49<(r212+r211) / (r212-r211)<-0.94 ···(15a) In each embodiment, it is more preferable that the numerical range of at least one of conditional expressions (3) to (15) is set as shown in the following conditional expressions (3b) to (15b), respectively.

[0041] 0.40 <skw / fw<0.95 ···(3b) 2.62<|f1 / f2|<4.83 (4b) 1.05 <M2 / fw<2.01 ···(5b) -1.00<β2t<-0.68 (6b) 0.21 <T1 / f1<0.44 ···(7b) 0.70<|f11 / f1|<1.37 (8b) -0.99<(r112+r111) / (r112-r111)<-0.22 ···(9b) 0.21 <MR / ft<0.32 ···(10b) 3.46 <f3 / fw<6.89 ···(11b) 1.21 <f4 / fw<4.21 ···(12b) 0.67<(D34w-D34t) / fw<1.10 (13b) 1.11<|f21 / f2|<1.86 (14b) -1.33<(r212+r211) / (r212-r211)<-0.95 (15b) The configuration of the zoom lens of each embodiment will be described in detail below. EXAMPLES

[0042] First, the zoom lens L0a in the first embodiment will be described with reference to FIG. 1 and FIGS. 2(a) and (b). FIG. 1 is a cross-sectional view of the zoom lens L0a at the wide-angle end when focusing at infinity. In FIG. 1, the left side is the object side (front) and the right side is the image side (rear). The aperture stop SP determines (limits) the light flux of the open F-number (Fno). When focusing from an object at infinity to an object at the closest distance, the focus lens group moves as shown by the arrow focus in FIG. 1. When the zoom lens L0a is used as an imaging optical system of a digital still camera or a digital video camera, the image plane IP becomes the imaging surface of an imaging element (photoelectric conversion element) such as a CCD sensor or a CMOS sensor. When the zoom lens L0a is used as an imaging optical system of a silver halide film camera, the image plane IP corresponds to the film surface. The above description is similar for other cross-sectional views.

[0043] FIG. 2(a) is an aberration diagram of the zoom lens L0a at the wide-angle end when focusing at infinity, and FIG. 2(b) is an aberration diagram of the zoom lens L0a at the telephoto end when focusing at infinity. In the spherical aberration diagram, Fno is the F-number, and shows the amount of spherical aberration for the d-line (wavelength 587.56 nm) and the g-line (wavelength 435.8 nm). In the astigmatism diagram, ΔS shows the amount of astigmatism in the sagittal image plane, and ΔM shows the amount of astigmatism in the meridional image plane. In the distortion aberration diagram, the amount of distortion aberration for the d-line is shown. In the chromatic aberration diagram, the amount of chromatic aberration for the g-line is shown. ω is the imaging half angle of view (°) based on paraxial calculation. The above explanation is similar for the other aberration diagrams.

[0044] The zoom lens L0a of this embodiment is composed of, in order from the object side to the image side, a first lens group L1, a second lens group L2, and a rear group LR. The rear group LR is composed of, in order from the object side to the image side, a third lens group L3 with positive refractive power, a fourth lens group L4 with positive refractive power, a fifth lens group L5 with negative refractive power, a sixth lens group L6 with positive refractive power, and a seventh lens group L7 with negative refractive power. The first lens group L1 is fixed with respect to the image plane IP during zooming (it does not move during zooming). Each lens group moves on a different trajectory (trajectory indicated by an arrow in FIG. 1) while changing the distance between them during zooming. The third lens group L3 has an aperture stop SP. During focusing from infinity to a close distance, the fifth lens group L5 moves to the image side, and the sixth lens group L6 moves to the image side. EXAMPLES

[0045] Next, the zoom lens L0b in the second embodiment will be described with reference to Fig. 3 and Figs. 4(a) and (b). Fig. 3 is a cross-sectional view of the zoom lens L0b at the wide-angle end when focusing on infinity. Fig. 4(a) is an aberration diagram of the zoom lens L0b at the wide-angle end when focusing on infinity, and Fig. 4(b) is an aberration diagram of the zoom lens L0b at the telephoto end when focusing on infinity.

[0046] The zoom lens L0b of this embodiment is composed of, in order from the object side to the image side, a first lens group L1, a second lens group L2, and a rear lens group LR. The rear lens group LR is composed of, in order from the object side to the image side, a third lens group L3 with positive refractive power, a fourth lens group L4 with positive refractive power, a fifth lens group L5 with negative refractive power, a sixth lens group L6 with negative refractive power, a seventh lens group L7 with positive refractive power, and an eighth lens group L8 with positive refractive power. The first lens group L1 is fixed with respect to the image plane IP during zooming (it does not move during zooming). The lens groups move on different trajectories (trajectories indicated by arrows in FIG. 3) while changing the intervals between them during zooming. The third lens group L3 has an aperture stop SP. During focusing from infinity to a close distance, the fifth lens group L5 moves to the object side, and the sixth lens group L6 moves to the image side. EXAMPLES

[0047] Next, the zoom lens L0c in Example 3 will be described with reference to Fig. 5 and Figs. 6(a) and (b). Fig. 5 is a cross-sectional view of the zoom lens L0c at the wide-angle end when focusing on infinity. Fig. 6(a) is an aberration diagram of the zoom lens L0c at the wide-angle end when focusing on infinity, and Fig. 6(b) is an aberration diagram of the zoom lens L0c at the telephoto end when focusing on infinity.

[0048] The zoom lens L0c of this embodiment is composed of, in order from the object side to the image side, a first lens group L1, a second lens group L2, and a rear group LR. The rear group LR is composed of, in order from the object side to the image side, a third lens group L3 with positive refractive power, a fourth lens group L4 with positive refractive power, a fifth lens group L5 with positive refractive power, a sixth lens group L6 with negative refractive power, and a seventh lens group L7 with negative refractive power. The first lens group L1 is fixed with respect to the image plane IP during zooming (it does not move during zooming). Each lens group moves on a different trajectory (trajectory indicated by an arrow in FIG. 5) while changing the distance between them during zooming. The third lens group L3 has an aperture stop SP. During focusing from infinity to a close distance, the fifth lens group L5 moves to the object side, and the sixth lens group L6 moves to the object side. EXAMPLES

[0049] Next, the zoom lens L0d in Example 4 will be described with reference to Fig. 7 and Figs. 8(a) and (b). Fig. 7 is a cross-sectional view of the zoom lens L0d at the wide-angle end when focusing on infinity. Fig. 8(a) is an aberration diagram of the zoom lens L0d at the wide-angle end when focusing on infinity, and Fig. 8(b) is an aberration diagram of the zoom lens L0d at the telephoto end when focusing on infinity.

[0050] The zoom lens L0d of this embodiment is composed of, in order from the object side to the image side, a first lens group L1, a second lens group L2, and a rear group LR. The rear group LR is composed of, in order from the object side to the image side, a third lens group L3 with positive refractive power, a fourth lens group L4 with positive refractive power, a fifth lens group L5 with negative refractive power, a sixth lens group L6 with positive refractive power, and a seventh lens group L7 with negative refractive power. The first lens group L1 is fixed with respect to the image plane IP during zooming (it does not move during zooming). Each lens group moves on a different trajectory (trajectory indicated by an arrow in FIG. 7) while changing the interval between them during zooming. The third lens group L3 has an aperture stop SP. During focusing from infinity to a close distance, the fifth lens group L5 moves to the image side, and the sixth lens group L6 moves to the image side. EXAMPLES

[0051] Next, the zoom lens L0e in Example 5 will be described with reference to Fig. 9 and Figs. 10(a) and (b). Fig. 9 is a cross-sectional view of the zoom lens L0e at the wide-angle end when focusing on infinity. Fig. 10(a) is an aberration diagram of the zoom lens L0e at the wide-angle end when focusing on infinity, and Fig. 10(b) is an aberration diagram of the zoom lens L0e at the telephoto end when focusing on infinity.

[0052] The zoom lens L0e of this embodiment is composed of, in order from the object side to the image side, a first lens group L1, a second lens group L2, and a rear group LR. The rear group LR is composed of, in order from the object side to the image side, a third lens group L3 with positive refractive power, a fourth lens group L4 with positive refractive power, a fifth lens group L5 with negative refractive power, and a sixth lens group L6 with positive refractive power. The first lens group L1, the third lens group L3, and the sixth lens group L6 are fixed with respect to the image plane IP during zooming (they do not move during zooming). Each lens group moves on a different trajectory (trajectory indicated by an arrow in FIG. 9) while changing the distance between them during zooming. The third lens group L3 has an aperture stop SP. During focusing from infinity to a close distance, the fifth lens group L5 moves to the image side.

[0053] In the zoom lenses of the respective embodiments, all surfaces having refractive power are made of refractive surfaces, which makes it possible to easily obtain optical performance equal to or better than that of a diffractive optical element or a reflective surface with a lower manufacturing difficulty compared to a diffractive optical element or a reflective surface.

[0054] In the zoom lens of each embodiment, image blur correction may be performed by moving a part of the zoom lens in a direction including a component perpendicular to the optical axis OA. By making the part to be moved during image blur correction a lens group arranged on the image side with a relatively small diameter, it is possible to configure a small actuator for driving and to miniaturize the lens device including the zoom lens. For example, image blur correction may be performed by moving the whole or part of the third lens group L3 in a direction including a component perpendicular to the optical axis OA.

[0055] Numerical Examples 1 to 5 corresponding to Examples 1 to 5, respectively, are shown below.

[0056] In the surface data of each numerical example, r represents the radius of curvature of each optical surface, and d (mm) represents the axial distance (distance on the optical axis) between the mth surface and the (m+1)th surface. Here, m is the surface number counted from the light incident side. In addition, nd represents the refractive index of each optical member with respect to the d-line, and νd represents the Abbe number based on the d-line of the optical member. In this specification, the Abbe number νd based on the d-line of a certain material is expressed as follows, when the refractive indices at the Fraunhofer d-line (587.6 nm), F-line (486.1 nm), C-line (656.3 nm), and g-line (wavelength 435.8 nm) are Nd, NF, and NC, respectively: νd=(Nd-1) / (NF-NC) It is expressed as:

[0057] In each numerical example, d, focal length (mm), F-number, and half angle of view (°) are all values ​​when the zoom lens of each example is focused on an object at infinity. The back focus BF is the air-equivalent value of the distance from the final lens surface (the surface closest to the image) of the zoom lens to the image surface. The total lens length of the zoom lens is the value obtained by adding the back focus to the distance from the first lens surface to the final lens surface.

[0058] [Numerical Example 1] Unit: mm Surface Data Surface number rd nd νd 1 -207.425 1.70 1.83481 42.7 2 95.825 4.21 3 393.916 2.00 1.72047 34.7 4 105.832 8.46 1.59522 67.7 5 -203.044 0.15 6 124.562 5.68 1.72916 54.7 7 -487.042 0.15 8 78.249 6.74 1.72916 54.7 9 -444.181 (variable) 10 8601.520 1.20 1.80400 46.5 11 28.416 5.54 12 -738.337 1.00 1.49700 81.5 13 63.533 3.06 14 -115.610 1.00 1.49700 81.5 15 35.816 3.84 1.90366 31.3 16 169.674 (variable) 17(Aperture) ∞ 1.00 18 67.476 3.22 1.84666 23.8 19 -1153.421 0.60 20 55.893 1.20 2.00100 29.1 21 34.548 6.77 1.51742 52.4 22 -82.213 3.04 23* -43.690 0.05 1.59022 30.1 24 -46.141 1.20 1.72916 54.7 25 4358.607 (variable) 26 172.999 7.58 1.49700 81.5 27 -27.250 1.19 1.83400 37.2 28 231.097 0.15 29 48.103 7.69 1.48749 70.2 30 -81.882 0.15 31 42.435 9.37 1.43875 94.7 32 -82.878 0.15 33* 78.425 2.40 1.85400 40.4 34 37.200 9.41 1.61800 63.4 35 -70.814 (variable) 36 161.341 1.20 1.77250 49.6 37 28.989 (variable) 38* 48.348 3.91 1.58313 59.4 39 95.150 (variable) 40 224.141 7.07 1.80810 22.8 41 -35.894 1.50 1.49700 81.5 42 361.709 7.03 43 -34.951 1.50 1.92286 20.9 44 -125.011 (variable) Image plane ∞ Aspheric Data Page 23 K = 0.00000e+00 A 4= 3.79285e-06 A 6=-1.22591e-10 A 8= 5.46760e-13 Page 33 K = 0.00000e+00 A 4=-7.34648e-06 A 6=-3.52185e-09 A 8= 3.20919e-13 Page 38 K = 0.00000e+00 A 4= 1.44392e-06 A 6= 4.53989e-09 A 8=-1.13675e-13 A10=-4.07591e-15 Various data Zoom ratio 4.12 Wide Angle Mid-Telephoto Focal length 24.72 50.19 101.86 F-number 2.90 2.90 2.90 Half angle of view 41.19 23.32 11.99 Lens total length 212.40 212.40 212.40 BF 11.98 26.45 21.74 d 9 0.80 16.04 34.02 d16 41.01 21.11 2.98 d25 19.68 9.87 0.79 d35 2.80 1.19 1.18 d37 7.64 6.92 6.23 d39 6.39 8.72 23.36 d44 11.98 26.45 21.74 Zoom lens group data Group starting plane focal length 1 1 83.05 2 10 -27.72 3 17 106.51 4 26 34.04 5 36 -45.93 6 38 163.53 7 40 -161.55 [Numerical Example 2] Unit: mm Surface Data Surface number rd nd νd 1 -208.117 2.00 2.00100 29.1 2 125.012 1.73 3 201.666 6.72 1.59522 67.7 4 -188.208 0.13 5 120.220 5.48 1.83481 42.7 6 -1189.696 0.15 7 69.551 5.71 1.83481 42.7 8 436.182 (variable) 9 214.024 1.20 1.90043 37.4 10 26.866 6.02 11 -282.246 1.20 1.59522 67.7 12 48.782 4.24 13 -64.715 1.20 1.49700 81.5 14 39.804 4.37 1.85025 30.1 15 -376.767 (variable) 16(Aperture) ∞ 1.00 17 76.845 3.20 1.84666 23.8 18 -332.575 0.50 19 56.009 0.90 2.00100 29.1 20 34.921 6.63 1.51742 52.4 21 -82.324 3.17 22* -40.899 0.05 1.59022 30.1 23 -43.512 1.20 1.72916 54.7 24 -438.046 (variable) 25 107.656 9.03 1.49700 81.5 26 -23.891 1.19 1.95375 32.3 27 -1561.807 0.15 28 57.153 9.76 1.43875 94.7 29 -41.965 0.15 30* 84.677 7.95 1.80400 46.5 31* -52.890 (variable) 32 185.555 2.58 1.89286 20.4 33 -333.256 1.20 1.61800 63.4 34 46.156 (variable) 35 77.039 1.20 2.00100 29.1 36 30.744 (variable) 37* 37.408 4.07 1.58313 59.4 38* 53.618 0.13 39 47.870 1.39 2.00069 25.5 40 25.731 9.31 1.61800 63.4 41 176.934 (variable) 42 54.577 7.41 1.84666 23.8 43 -80.249 1.50 1.48749 70.2 44 42.160 7.49 45 -49.214 1.50 1.92286 20.9 46 -97.002 (variable) Image plane ∞ Aspheric Data Page 22 K = 0.00000e+00 A 4= 4.39269e-06 A 6= 1.10097e-09 A 8= 6.31456e-13 Page 30 K = 0.00000e+00 A 4=-5.80494e-06 A 6=-2.08319e-09 A 8=-2.99833e-12 Page 31 K = 0.00000e+00 A 4= 1.13763e-06 A 6=-3.28114e-09 Page 37 K = 0.00000e+00 A 4= 2.38842e-06 A 6=-2.70374e-09 A 8=-1.84658e-11 A10= 2.89507e-14 Page 38 K = 0.00000e+00 A 4= 6.75134e-08 A 6=-3.59874e-09 A 8=-2.39776e-11 A10= 3.36099e-14 Various data Zoom ratio 4.13 Wide Angle Mid-Telephoto Focal length 24.73 50.23 102.12 F-number 2.90 2.90 2.90 Half angle of view 41.19 23.30 11.96 Lens total length 211.51 211.51 211.51 BF 11.80 26.61 26.29 d 8 0.80 15.28 30.36 d15 39.32 19.23 2.99 d24 19.57 9.93 0.78 d31 4.00 1.22 2.88 d34 4.47 7.50 6.25 d36 7.75 7.49 7.08 d41 1.00 1.44 12.05 d46 11.80 26.61 26.29 Zoom lens group data Group starting plane focal length 1 1 79.54 2 9 -24.54 3 16 97.60 4 25 34.35 5 32 -131.33 6 35 -51.78 7 37 123.01 8 42 770.84 [Numerical Example 3] Unit: mm Surface Data Surface number rd nd νd 1 -181.919 1.70 1.90043 37.4 2 111.072 3.71 3 364.499 5.59 1.59522 67.7 4 -177.536 0.14 5 154.743 4.78 1.75500 52.3 6 -870.763 0.15 7 84.502 7.28 1.75500 52.3 8 -367.735 (variable) 9 -2513.905 1.30 1.72916 54.7 10 27.941 6.20 11 -452.183 1.20 1.59522 67.7 12 68.302 2.86 13 -147.630 1.20 1.49700 81.5 14 37.027 4.02 1.90043 37.4 15 197.666 (variable) 16(Aperture) ∞ 1.00 17 70.360 3.19 1.84666 23.8 18 -1084.899 0.60 19 62.970 1.20 2.05090 26.9 20 36.953 6.53 1.56732 42.8 21 -87.660 3.17 22* -43.587 0.05 1.59022 30.1 23 -46.864 1.40 1.77250 49.6 24 3434.700 (variable) 25 68.421 7.75 1.49700 81.5 26 -34.337 1.19 1.83400 37.2 27 94.819 0.15 28 45.071 5.49 1.49700 81.5 29 1775.190 0.15 30 38.956 9.94 1.49700 81.5 31 -94.914 2.39 32* 78.620 2.50 1.85400 40.4 33* 49.978 (variable) 34* 37.006 8.81 1.58313 59.4 35* -88.576 (variable) 36 123.459 1.20 2.00100 29.1 37 40.182 (variable) 38 73.297 8.72 1.84666 23.8 39 -41.340 1.40 1.60311 60.6 40 49.128 8.20 41 -33.125 1.40 1.92286 20.9 42 -59.144 (variable) Image plane ∞ Aspheric Data Page 22 K = 0.00000e+00 A 4= 3.89058e-06 A 6= 6.70856e-10 A 8=-1.58188e-12 Page 32 K = 0.00000e+00 A 4= 4.26123e-06 A 6=-9.76054e-09 A 8=-4.97564e-12 Page 33 K = 0.00000e+00 A 4= 1.08509e-05 A 6=-5.04108e-09 A 8=-2.02185e-12 A10= 5.27144e-15 Page 34 K = 0.00000e+00 A 4=-1.80819e-06 A 6=-1.87700e-09 A 8= 3.87938e-13 Page 35 K = 0.00000e+00 A 4= 4.45032e-06 A 6=-4.27576e-09 A 8= 3.65399e-12 Various data Zoom ratio 4.12 Wide Angle Mid-Telephoto Focal length 24.72 50.22 101.96 F-number 2.90 2.90 2.90 Half angle of view 41.19 23.31 11.98 Lens total length 211.02 211.02 211.02 BF 11.85 26.68 22.74 d 8 0.80 16.99 35.41 d15 44.29 21.72 3.00 d24 20.71 11.73 0.78 d33 4.43 7.45 8.57 d35 2.11 1.69 3.52 d37 10.27 8.21 20.44 d42 11.85 26.68 22.74 Zoom lens group data Group starting plane focal length 1 1 94.31 2 9 -29.02 3 16 127.17 4 25 83.32 5 34 45.95 6 36 -59.94 7 38 -203.31 [Numerical Example 4] Unit: mm Surface Data Surface number rd nd νd 1 -266.746 1.60 1.90043 37.4 2 98.340 2.81 3 192.058 6.58 1.53775 74.7 4 -241.263 0.15 5 119.575 5.31 1.72916 54.7 6 -1682.093 0.15 7 76.157 6.72 1.72916 54.7 8 -880.300 (variable) 9 915.083 1.20 1.88300 40.8 10 29.841 5.73 11 -218.330 1.00 1.59522 67.7 12 63.389 3.69 13 -74.215 1.10 1.49700 81.5 14 41.057 4.98 1.77047 29.7 15 -204.631 (variable) 16(Aperture) ∞ 1.00 17 78.578 3.15 1.84666 23.8 18 -594.031 0.60 19 59.615 1.20 2.00100 29.1 20 36.734 7.47 1.51742 52.4 21 -83.322 3.11 22* -44.261 0.05 1.59022 30.1 23 -47.091 1.20 1.77250 49.6 24 -640.625 (variable) 25 255.634 8.10 1.49700 81.5 26 -27.474 1.30 1.90043 37.4 27 -222.061 0.15 28 41.537 8.18 1.49700 81.5 29 -105.932 2.30 30 63.231 6.49 1.49700 81.5 31 -97.379 0.15 32* 85.354 2.40 1.85400 40.4 33 34.925 8.89 1.60311 60.6 34 -78.017 (variable) 35 157.315 1.20 1.72916 54.7 36 28.256 (variable) 37* 47.159 4.54 1.58313 59.4 38 160.935 (variable) 39 210.344 5.69 1.80518 25.4 40 -46.896 1.50 1.48749 70.2 41 59.110 9.57 42 -33.883 1.20 2.00069 25.5 43 -66.006 (variable) Image plane ∞ Aspheric Data Page 22 K = 0.00000e+00 A 4= 3.72124e-06 A 6= 3.39835e-10 A 8= 6.96887e-13 Page 32 K = 0.00000e+00 A 4=-7.10364e-06 A 6=-3.27713e-09 A 8=-1.38031e-12 Page 37 K = 0.00000e+00 A 4= 1.68172e-06 A 6= 3.21879e-09 A 8= 5.86323e-12 A10=-1.26470e-14 Various data Zoom ratio 4.12 Wide Angle Mid-Telephoto Focal length 24.78 50.31 102.06 F-number 2.90 2.90 2.90 Half angle of view 41.12 23.27 11.97 Lens total length 211.98 211.98 211.98 BF 11.63 25.76 19.01 d 8 0.80 16.58 34.70 d15 42.76 21.90 2.98 d24 19.63 10.61 0.79 d34 2.50 1.78 1.10 d36 8.07 7.90 7.19 d38 6.12 7.00 25.75 d43 11.63 25.76 19.01 Zoom lens group data Group starting plane focal length 1 1 90.57 2 9 -27.00 3 16 119.23 4 25 35.02 5 35 -47.42 6 37 112.74 7 39 -90.78 [Numerical Example 5] Unit: mm Surface Data Surface number rd nd νd 1 -8741.959 1.40 2.00100 29.1 2 77.425 2.07 3 132.828 5.55 1.48749 70.2 4 -278.544 0.15 5 81.695 4.36 1.72916 54.7 6 698.842 0.15 7 52.270 5.59 1.72916 54.7 8 496.392 (variable) 9 231.928 0.90 1.80400 46.6 10 19.761 4.24 11 -78.088 0.80 1.59282 68.6 12 53.314 3.20 13 -27.410 0.80 1.49700 81.5 14 57.444 2.55 15 69.921 2.53 1.85025 30.1 16 -72.259 (variable) 17(Aperture) ∞ 1.00 18 104.572 2.48 1.84666 23.8 19 -84.594 0.60 20 55.992 1.00 1.90043 37.4 21 31.491 4.61 1.49700 81.5 22 -70.253 3.02 23* -28.727 0.05 1.59022 30.1 24 -29.778 0.80 1.80518 25.4 25 -100.170 (variable) 26 18.384 6.47 1.49700 81.5 27 -138.084 2.89 28* 35.239 2.00 1.85400 40.4 29 12.971 8.26 1.53775 74.7 30 -46.153 (variable) 31 168.469 0.80 1.69680 55.5 32 16.983 3.73 33* 31.760 0.05 1.59022 30.1 34 29.014 3.06 1.59551 39.2 35 123.379 (variable) 36 -344.548 7.53 1.90366 31.3 37 -18.233 1.20 1.84666 23.8 38 -96.734 (variable) Image plane ∞ Aspheric Data Page 23 K = 0.00000e+00 A 4= 8.09779e-06 A 6=-1.18636e-08 A 8= 6.70206e-11 Page 28 K = 0.00000e+00 A 4=-2.83986e-05 A 6=-4.36898e-08 A 8=-1.47706e-10 Page 33 K = 0.00000e+00 A 4= 7.39408e-06 A 6= 5.64098e-08 A 8= 1.50619e-10 A10=-4.36865e-13 Various data Zoom ratio 3.77 Wide Angle Mid-Telephoto Focal length 15.45 30.00 58.20 F-number 2.90 2.90 2.90 Half angle of view 41.48 24.48 13.21 Lens length 143.99 143.99 143.99 BF 11.90 11.90 11.90 d 8 0.80 12.86 25.80 d16 27.48 15.42 2.48 d25 14.75 4.45 0.78 d30 2.62 1.54 5.64 d35 2.60 13.97 13.54 d38 11.90 11.90 11.90 Zoom lens group data Group starting plane focal length 1 1 70.23 2 9 -18.13 3 17 85.18 4 26 26.26 5 31 -47.32 6 36 106.66 Table 1 shows values ​​corresponding to conditional expressions (1) to (15) in Numerical Examples 1 to 5.

[0059] [Table 1]

[0060] (Imaging device) Next, referring to FIG. 11, an imaging device (digital still camera) 10 equipped with a zoom lens of each embodiment will be described. FIG. 11 is a schematic diagram of the imaging device 10. The imaging device 10 includes a camera body 13, a lens device 11 including a zoom lens (L0a to L0e) of any one of the embodiments 1 to 5, and an imaging element (light receiving element) 12 that photoelectrically converts an image formed by the zoom lens. The imaging element 12 is a photoelectric conversion element such as a CCD sensor or a CMOS sensor. The lens device 11 and the camera body 13 may be integrally configured, or may be detachably configured. The imaging device 10 can achieve a small size, light weight, and high optical performance. The zoom lens of each embodiment is not limited to the imaging device 10 shown in FIG. 11, but can also be applied to various imaging devices such as broadcast cameras, silver halide film cameras, and surveillance cameras.

[0061] According to each embodiment, it is possible to provide a zoom lens and an imaging device that are small in size, have a high zoom ratio and a large aperture ratio, and yet achieve high image quality and high-speed zoom operation.

[0062] The disclosure of each embodiment includes the following configuration.

[0063] (Configuration 1) A zoom lens comprising, in order from the object side to the image side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a subsequent group having at least four lens groups that move during zooming, During zooming, the spacing between adjacent lens groups changes, During zooming and focusing, the first lens group does not move relative to the image plane, Let Lw be the distance on the optical axis from the vertex position of the surface closest to the object in the zoom lens at the wide-angle end to the image plane, fw be the focal length of the zoom lens at the wide-angle end, T2 be the distance on the optical axis from the vertex position of the surface closest to the object in the second lens group to the vertex position of the surface closest to the image side, and f2 be the focal length of the second lens group. 7.50 <Lw / fw<15.00 0.20 <T2 / |f2|<0.85 A zoom lens characterized by satisfying the following conditional expressions: (Configuration 2) When the distance on the optical axis from the vertex position of the surface closest to the image side of the zoom lens at the wide-angle end to the image surface is skw, 0.20 <skw / fw<1.50 2. The zoom lens according to claim 1, wherein the following condition is satisfied: (Configuration 3) When the focal length of the first lens group is f1 and the focal length of the second lens group is f2, 1.50<|f1 / f2|<7.70 3. The zoom lens according to configuration 1 or 2, wherein the following condition is satisfied: (Configuration 4) When the absolute value of the movement amount of the second lens group during zooming from the wide-angle end to the telephoto end is M2, 0.60 <M2 / fw<3.20 4. The zoom lens according to any one of the configurations 1 to 3, wherein the following condition is satisfied: (Configuration 5) When the lateral magnification of the second lens group at the telephoto end is βT, -2.00<β2t<-0.30 5. The zoom lens according to any one of the first to fourth aspects, wherein the following condition is satisfied: (Configuration 6) Let f1 be the focal length of the first lens group, and T1 be the distance on the optical axis from the vertex position of the surface closest to the object side in the first lens group to the vertex position of the surface closest to the image side, 0.10 <T1 / f1<0.70 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 according to any one of configurations 1 to 6, wherein the first lens group has a first lens having negative refractive power closest to the object side. (Configuration 8) When the focal length of the first lens group is f1 and the focal length of the first lens is f11, 0.40<|f11 / f1|<2.20 8. The zoom lens according to claim 7, wherein the following condition is satisfied: (Configuration 9) When the radius of curvature of the object-side surface of the first lens is r111 and the radius of curvature of the image-side surface of the first lens is r112, The zoom lens according to configuration 7 or 8, wherein the following condition is satisfied: -2.00<(r112+r111) / (r112-r111)<-0.20. (Configuration 10) Let MR be the maximum absolute value of the amount of movement of the lens group constituting the subsequent group during zooming from the wide-angle end to the telephoto end, and ft be the focal length of the zoom lens at the telephoto end. 0.10 <MR / ft<0.50 10. The zoom lens according to any one of configurations 1 to 9, wherein the following condition is satisfied: (Configuration 11) 11. The zoom lens according to any one of Configurations 1 to 10, wherein the subsequent group comprises, in order from the object side to the image side, a third lens group having positive refractive power and a fourth lens group having positive refractive power. (Configuration 12) When the focal length of the third lens group is f3, 2.00 <f3 / fw<11.00 12. The zoom lens according to claim 11, wherein the following condition is satisfied: (Configuration 13) When the focal length of the fourth lens group is f4, 0.70 <f4 / fw<6.70 13. The zoom lens according to claim 11 or 12, wherein the following condition is satisfied: (Configuration 14) Let D34w be the distance on the optical axis from the surface vertex position of the surface closest to the image in the third lens group to the surface vertex position of the surface closest to the object in the fourth lens group at the wide-angle end, and let D34t be the distance on the optical axis from the surface vertex position of the surface closest to the image in the third lens group to the surface vertex position of the surface closest to the object in the fourth lens group at the telephoto end, 0.40<(D34w-D34t) / fw<1.80 14. The zoom lens according to any one of the configurations 11 to 13, wherein the following condition is satisfied: (Configuration 15) 15. A zoom lens according to any one of Configurations 11 to 14, wherein only the lens group disposed on the image side of the fourth lens group moves during focusing. (Configuration 16) 16. A zoom lens according to any one of configurations 1 to 15, wherein the first lens group has at least three lenses having positive refractive power. (Configuration 17) 17. A zoom lens according to any one of configurations 1 to 16, wherein the second lens group has a second lens having negative refractive power closest to the object side. (Configuration 18) When the focal length of the second lens is f21, 0.60<|f21 / f2|<3.00 18. The zoom lens according to claim 17, wherein the following condition is satisfied: (Configuration 19) When the radius of curvature of the object-side surface of the second lens is r211 and the radius of curvature of the image-side surface of the second lens is r212, -2.60<(r212+r211) / (r212-r211)<-0.50 19. The zoom lens according to configuration 17 or 18, wherein the following condition is satisfied: (Configuration 20) The zoom lens according to any one of configurations 1 to 19, wherein the second lens group has, in order from the object side to the image side, a lens with negative refractive power, a lens with negative refractive power, a lens with negative refractive power, and a lens with positive refractive power. (Configuration 21) A zoom lens according to any one of configurations 1 to 20; an image sensor that receives an image formed by the zoom lens.

[0064] Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of the gist of the present invention. [Explanation of symbols]

[0065] L0a~L0e Zoom Lens L1 First lens group L2 Second lens group LR Successor group

Claims

1. A zoom lens comprising, in order from the object side to the image side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a subsequent group having at least four lens groups that move during zooming, When zooming, the spacing between adjacent lens groups changes, During zooming and focusing, the first lens group does not move relative to the image plane, the first lens group includes at least three lenses having a positive refractive power; Let Lw be the distance on the optical axis from the surface vertex position of the lens surface closest to the object in the zoom lens at the wide-angle end to the image plane, fw be the focal length of the zoom lens at the wide-angle end, T2 be the distance on the optical axis from the surface vertex position of the lens surface closest to the object in the second lens group to the surface vertex position of the lens surface closest to the image side, f2 be the focal length of the second lens group, and skw be the distance on the optical axis from the surface vertex position of the lens surface closest to the image side in the zoom lens at the wide-angle end, 7.50<Lw / fw<15.00 0.20<T2 / |f2|<0.85 0.20<skw / fw<1.50 A zoom lens characterized by satisfying the following conditional expressions:

2. When the focal length of the first lens group is f1 and the focal length of the second lens group is f2, 1.50<|f1 / f2|<7.70 2. The zoom lens according to claim 1, wherein the following condition is satisfied:

3. When the absolute value of the movement amount of the second lens unit during zooming from the wide-angle end to the telephoto end is M2, 0.60<M2 / fw<3.20 2. The zoom lens according to claim 1, wherein the following condition is satisfied:

4. When the lateral magnification of the second lens group at the telephoto end is β2T, -2.00<β2t<-0.30 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 distance on the optical axis from the vertex position of the surface closest to the object side to the vertex position of the surface closest to the image side in the first lens group is T1, 0.10<T1 / f1<0.70 2. The zoom lens according to claim 1, wherein the following condition is satisfied:

6. 2. The zoom lens according to claim 1, wherein the first lens group has a first lens element having negative refractive power closest to the object side.

7. When the focal length of the first lens group is f1 and the focal length of the first lens is f11, 0.40<|f11 / f1|<2.20 7. The zoom lens according to claim 6, wherein the following condition is satisfied:

8. When the radius of curvature of the object-side surface of the first lens is r111 and the radius of curvature of the image-side surface of the first lens is r112, -2.00<(r112+r111) / (r112-r111)<-0.20 7. The zoom lens according to claim 6, wherein the following condition is satisfied:

9. When the maximum absolute value of the movement amount of the lens group constituting the subsequent group during zooming from the wide-angle end to the telephoto end is MR, and the focal length of the zoom lens at the telephoto end is ft, 0.10<MR / ft<0.50 2. The zoom lens according to claim 1, wherein the following condition is satisfied:

10. 2. The zoom lens according to claim 1, wherein the subsequent lens group comprises, in order from the object side to the image side, a third lens group having a positive refractive power and a fourth lens group having a positive refractive power.

11. When the focal length of the third lens group is f3, 2.00<f3 / fw<11.00 11. The zoom lens according to claim 10, wherein the following condition is satisfied:

12. When the focal length of the fourth lens group is f4, 0.70<f4 / fw<6.70 11. The zoom lens according to claim 10, wherein the following condition is satisfied:

13. Let D34w be the distance on the optical axis from the surface vertex position of the surface closest to the image in the third lens group to the surface vertex position of the surface closest to the object in the fourth lens group at the wide-angle end, and let D34t be the distance on the optical axis from the surface vertex position of the surface closest to the image in the third lens group to the surface vertex position of the surface closest to the object in the fourth lens group at the telephoto end, 0.40<(D34w-D34t) / fw<1.80 11. The zoom lens according to claim 10, wherein the following condition is satisfied:

14. 11. The zoom lens according to claim 10, wherein only the lens group disposed on the image side of the fourth lens group moves during focusing.

15. 2. The zoom lens according to claim 1, wherein the second lens group has a second lens element having negative refractive power closest to the object side.

16. When the focal length of the second lens is f21, 0.60<|f21 / f2|<3.00 16. The zoom lens according to claim 15, wherein the following condition is satisfied:

17. When the radius of curvature of the object-side surface of the second lens is r211 and the radius of curvature of the image-side surface of the second lens is r212, -2.60<(r212+r211) / (r212-r211)<-0.50 16. The zoom lens according to claim 15, wherein the following condition is satisfied:

18. 2. The zoom lens according to claim 1, wherein the second lens group comprises, in order from the object side to the image side, a lens with negative refractive power, a lens with negative refractive power, a lens with negative refractive power, and a lens with positive refractive power.

19. a zoom lens according to any one of claims 1 to 18; an image sensor that receives an image formed by the zoom lens.

Images