Zoom lens and imaging device having the same

Abstract

To provide a zoom lens which is compact and yet offers a high zoom ratio and superior optical performance, and to provide an image capturing device having the same.SOLUTION: A zoom lens provided herein comprises a first lens group (B1) having positive refractive power, a second lens group (B2) having negative refractive power, a third lens group (B3) having positive refractive power, and a rear group (RL) comprising a plurality of lens groups, arranged in order from the object side to the image side, and is configured such that distances between adjacent lens groups change while zooming. The rear group comprises a plurality of lens groups having negative refractive power and a plurality of lens groups having positive refractive power. When zooming from the wide-angle end to the telephoto end, the first lens group moves towards the object side, while the second lens group moves towards the object side after moving towards the image side. A focal length f1 of the first lens group, a focal length f2 of the second lens group, and a displacement of the first lens group while zooming from the wide-angle end to the telephoto end satisfy given relationships.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[0002] Zoom lenses used in imaging devices are required to have a high zoom ratio and high optical performance while being compact.

[0003] Patent Documents 1 and 2 describe a zoom lens that achieves both a high zoom ratio and high optical performance, and that is composed of multiple lens groups arranged in this 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 third lens group with positive refractive power. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-148731 [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-235093 Summary of the Invention [Problem to be solved by the invention]

[0005] However, although the zoom lenses disclosed in Patent Documents 1 and 2 have a high zoom ratio and excellent optical performance, they do not satisfy the demand for compactness. To achieve this, it is important to appropriately set the zoom type and the lens group that moves during zooming.

[0006] An object of the present invention is to provide a zoom lens that is compact yet has both a high zoom ratio and good optical performance, and an imaging device having the same. [Means for solving the problem]

[0007] A zoom lens comprising a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, and a rear group including a plurality of lens groups, arranged in this order from the object side to the image side, wherein the spacing between adjacent lens groups changes during zooming, and the rear group includes a plurality of lens groups having a negative refractive power and a plurality of lens groups having a positive refractive power, and during zooming from the wide-angle end to the telephoto end, the first lens group moves toward the object side, and the second lens group moves toward the image side and then moves toward the object side. the first lens group comprises a negative lens, a positive lens, and a positive lens arranged in this order from the object side to the image side, the focal length of the first lens group is f1, the focal length of the second lens group is f2, the amount of movement of the first lens group during zooming from the wide-angle end to the telephoto end is m1, the composite focal length of the rear lens group at the wide-angle end is fr, the zoom lens has an aperture stop, and the focal length of the lens group in the rear lens group that has negative refractive power and is closest to the aperture stop is fsi, 5.50 <f1 / |f2|<7.50 0.56 <m1 / f1<1.19 2.71 <fr / |f2|<6.53 0.17 <f2 / fsi<0.38 A zoom lens characterized by satisfying the following conditional expressions:

[0008] Other objects and features of the present invention are illustrated in the following examples. [Effects of the Invention]

[0009] According to the present invention, it is possible to realize a zoom lens that is compact yet has both a high zoom ratio and good optical performance. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a cross-sectional view of a lens according to a first embodiment of the present invention. [Figure 2] 1A, 1B, and 1C are aberration diagrams of Example 1 of the present invention at the wide-angle end, the intermediate end, and the telephoto end when focusing on infinity. [Figure 3]FIG. 10 is a cross-sectional view of a lens according to a second embodiment of the present invention. [Figure 4] 10A, 10B, and 10C are aberration diagrams of Example 2 of the present invention at the wide-angle end, the intermediate end, and the telephoto end when focusing on infinity. [Figure 5] FIG. 10 is a cross-sectional view of a lens according to a third embodiment of the present invention. [Figure 6] 10A to 10C are aberration diagrams of Example 3 of the present invention at the wide-angle end (A), the intermediate end (B), and the telephoto end (C) when focusing on infinity. [Figure 7] FIG. 10 is a cross-sectional view of a lens according to a fourth embodiment of the present invention. [Figure 8] 10A to 10C are aberration diagrams of Example 3 of the present invention at the wide-angle end (A), the intermediate end (B), and the telephoto end (C) when focusing on infinity. [Figure 9] FIG. 10 is a cross-sectional view of a lens according to a fifth embodiment of the present invention. [Figure 10] 10A to 10C are aberration diagrams of Example 3 of the present invention at the wide-angle end (A), the intermediate end (B), and the telephoto end (C) when focusing on infinity. [Figure 11] FIG. 10 is a lateral aberration diagram at the telephoto end when image stabilization is performed by 0.4 degrees in Example 1 of the present invention. [Figure 12] 1 is a schematic diagram illustrating a main part of an imaging device according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0011] A zoom lens according to an embodiment of the present invention comprises, arranged in order from the object side to the image side, a first lens group B1 with positive refractive power (optical power = the reciprocal of focal length), a second lens group B2 with negative refractive power, a third lens group B3 with positive refractive power, and a rear group RL including a plurality of subsequent lens groups toward the image side. The rear group RL has a plurality of lens groups with negative refractive power and a plurality of lens groups with positive refractive power. Specifically, the rear group RL has, in order from the object side to the image side, fourth to seventh lens groups (B4 to B7), which are lens groups with at least positive or negative refractive power. The spacing between adjacent lens groups changes during zooming.

[0012] In a zoom lens according to an embodiment of the present invention, when zooming from the wide-angle end to the telephoto end, the first lens group B1 moves toward the object side along the optical axis, and the second lens group B2 moves toward the image side along the optical axis and then moves toward the object side.

[0013] Let f1 be the focal length of the first lens unit B1, f2 be the focal length of the second lens unit B2, and m1 be the amount of movement of the first lens unit B1 during zooming from the wide-angle end to the telephoto end. 5.50 <f1 / |f2|<7.50 ···(1) 0.56 <m1 / f1<1.19 ···(2) In this embodiment, the sign of the movement amount is negative when the first lens unit B1 is located closer to the object at the telephoto end than at the wide-angle end, and positive when it is located closer to the image.

[0014] By satisfying the above conditional expressions (1) and (2), it is possible to realize a zoom lens that is compact yet has both a high zoom ratio and good optical performance.

[0015] A zoom lens according to an embodiment of the present invention comprises, arranged in order from the object side to the image side, a first lens group with positive refractive power, a second lens group with strong negative refractive power, a third lens group with positive refractive power, and a rear group including multiple lens groups, thereby achieving both a high zoom ratio and excellent optical performance.

[0016] The zoom lens according to the embodiment of the present invention further has a rear lens group RL on the image side, and the rear lens group comprises multiple negative lens groups and multiple positive lens groups, thereby suppressing various aberrations while achieving a high zoom ratio.

[0017] In the zoom lens according to the embodiment of the present invention, when zooming from the wide-angle end to the telephoto end, the first lens unit B1 moves toward the object side along the optical axis, and the second lens unit B2 moves toward the image side along the optical axis and then moves toward the object side, thereby achieving both a high zoom ratio and compact size.

[0018] Conditional expression (1) defines a preferable range of the focal length of the first lens group B1 and the focal length of the second lens group B2 by the ratio. If the upper limit of conditional expression (1) is exceeded and the focal length of the first lens group B1 becomes too long, it becomes easier to correct aberrations, but the amount of zooming movement of the movable group within the first lens group B1 increases, making compactness difficult, which is undesirable. If the lower limit of conditional expression (1) is exceeded and the focal length of the first lens group B1 becomes too short, it becomes difficult to correct spherical aberration at the telephoto end, which is undesirable.

[0019] Conditional expression (2) defines, by a ratio, a preferable range of the movement amount of the first lens unit B1 from the wide-angle end to the telephoto end and the focal length of the first lens unit B1. If the upper limit of conditional expression (2) is exceeded and the movement amount of the first lens unit B1 becomes too large, it becomes easy to correct aberrations, but this is not preferable for compactness. If the lower limit of conditional expression (2) is exceeded and the movement amount of the first lens unit B1 becomes too small, it becomes effective for compactness, but it becomes difficult to correct spherical aberration, especially at the telephoto end, which is not preferable.

[0020] It is also preferable to perform focusing using the strongest negative lens unit in the rear group RL, which tends to have a relatively small diameter in the entire system, allowing the focusing drive mechanism to be made compact.

[0021] It is even more preferable to perform focusing using the sixth lens unit B6 having negative refractive power, in order to effectively correct various aberrations during zooming.

[0022] Furthermore, it is preferable to use the negative lens group in the rear group RL closest to the aperture stop as an image stabilization lens group by moving it in a direction that includes a component perpendicular to the optical axis during image blur correction. The negative lens group in the rear group RL closest to the aperture stop is easy to keep aberration fluctuations small during image stabilization, and can be made small in diameter, making it possible to realize a compact image stabilization drive device.

[0023] It is even more preferable to perform image stabilization using the fourth lens unit B4 having negative refractive power, in order to effectively correct various aberrations during image stabilization.

[0024] Furthermore, when the focal length of the second lens unit B2 is f2 and the combined focal length of the rear unit RL at the wide-angle end is fr, it is preferable to satisfy the following conditional expression.

[0025] 2.71 <fr / |f2|<6.53 ···(3) Conditional expression (3) defines, by a ratio, a preferable range of the absolute value of the focal length of the second lens group B2 and the combined focal length of the rear group. If the upper limit of conditional expression (3) is exceeded and the absolute value of the focal length of the second lens group B2 becomes too small, it becomes easy to ensure the desired amount of magnification, but the curvature of field becomes large, particularly at the wide-angle end, which is undesirable. If the lower limit of conditional expression (3) is exceeded and the absolute value of the focal length of the second lens group B2 becomes too large, it becomes easy to correct aberrations, but in order to ensure the desired amount of magnification, the amount of movement during zooming becomes too large, which is undesirable for compactness.

[0026] Furthermore, when the focal length of the first lens unit B1 is f1 and the focal length of the third lens unit B3 is f3, it is preferable that the following conditional expression be satisfied.

[0027] 1.61 <f1 / f3<3.55 ···(4) Conditional expression (4) defines a preferable range of the focal length of the first lens group B1 and the focal length of the third lens group B3 by the ratio. If the upper limit of conditional expression (4) is exceeded and the focal length of the first lens group B1 becomes too long, it becomes easier to correct aberrations, but in order to ensure the desired amount of magnification, the amount of movement of the first lens group B1 during zooming becomes too large, which is undesirable for compactness. If the lower limit of conditional expression (4) is exceeded and the focal length of the first lens group B1 becomes too short, it becomes preferable for compactness, but it becomes difficult to correct spherical aberration, especially at the telephoto end, which is undesirable.

[0028] Furthermore, when the focal length of the second lens unit B2 is f2 and the focal length of the third lens unit B3 is f3, it is preferable that the following conditional expression be satisfied.

[0029] 0.23<|f2| / f3<0.53 (5) Conditional expression (5) defines, by a ratio, a preferable range of the absolute value of the focal length of the second lens group B2 and the focal length of the third lens group B3. If the upper limit of conditional expression (5) is exceeded and the focal length of the third lens group B3 becomes too long, it becomes easier to correct aberrations, but in order to ensure the desired amount of magnification, the movement amount of the third lens group B3 during zooming becomes too large, which is undesirable for compactness. If the lower limit of conditional expression (5) is exceeded and the focal length of the third lens group B3 becomes too short, it becomes preferable for compactness, but it becomes difficult to correct spherical aberration, especially at the telephoto end, which is undesirable.

[0030] Furthermore, when the focal length of the lens group in the rear group RL having the strongest negative refractive power (the lens group having the smallest absolute value of the focal length among the multiple lens groups with negative refractive power included in the rear group RL) is denoted by ff and the focal length of the second lens group B2 is denoted by f2, it is preferable to satisfy the following conditional expression:

[0031] 0.38 <f2 / ff<1.02 ···(6) Conditional expression (6) defines a preferable range, by the ratio, between the focal length of the lens group having the strongest negative refractive power in the rear group RL that performs focusing and the focal length of the second lens group B2. If the upper limit of conditional expression (6) is exceeded and the focal length of the second lens group B2 becomes too long, it becomes easier to ensure the desired amount of magnification, but it becomes difficult to correct curvature of field, particularly at the wide-angle end, which is not preferable. If the lower limit of conditional expression (6) is exceeded and the focal length of the second lens group B2 becomes too short, it becomes easier to correct aberrations, but it becomes unfavorable for compactness because the amount of movement during zooming increases to ensure the desired amount of magnification.

[0032] Furthermore, when the focal length of the second lens unit B2 is f2 and the back focus at the wide-angle end is skw, it is preferable to satisfy the following conditional expression.

[0033] 0.62<|f2| / skw<1.60 (7) Conditional expression (7) defines, by a ratio, a preferable range between the absolute value of the focal length of the second lens unit B2 and the back focal length at the wide-angle end. If the upper limit of conditional expression (7) is exceeded and the absolute value of the focal length of the second lens unit B2 becomes too small, it becomes easier to ensure the desired amount of magnification, but it becomes difficult to correct curvature of field, particularly at the wide-angle end, which is undesirable. If the lower limit of conditional expression (7) is exceeded and the absolute value of the focal length of the second lens unit B2 becomes too large, it becomes easier to correct aberrations, but it becomes undesirable from the perspective of compactness because the amount of movement during zooming increases to ensure the desired amount of magnification.

[0034] Furthermore, when the focal length of the third lens unit B3 is f3 and the back focus at the wide-angle end is skw, it is preferable to satisfy the following conditional expression.

[0035] 1.70 <f3 / skw<4.39 ···(8) Conditional expression (8) defines a preferable range of the focal length of the third lens unit B3 and the back focal length at the wide-angle end, expressed as a ratio. If the upper limit of conditional expression (8) is exceeded and the focal length of the third lens unit B3 becomes too short, it becomes easier to ensure the desired amount of magnification, but it becomes difficult to correct spherical aberration, particularly at the telephoto end, which is undesirable. If the lower limit of conditional expression (8) is exceeded and the focal length of the third lens unit B3 becomes too long, it becomes easier to correct aberration, but it becomes undesirable from the perspective of compactness because the amount of movement during zooming increases to ensure the desired amount of magnification.

[0036] Furthermore, when the focal length of the second lens unit B2 is f2 and the focal length of the lens unit having negative refractive power that is closest to the aperture stop in the rear unit RL is fsi, it is preferable to satisfy the following conditional expression:

[0037] 0.17 <f2 / fsi<0.38 ···(9) Conditional expression (9) defines, by a ratio, a preferable range of the focal length of the second lens group B2 and the focal length of the lens group having negative refractive power in the rear group RL that performs image stabilization and is closest to the aperture stop. If the upper limit of conditional expression (9) is exceeded and the focal length of the second lens group B2 becomes too long, this is favorable for compactness, but it is unfavorable because it makes it difficult to correct curvature of field, particularly at the wide-angle end. If the lower limit of conditional expression (9) is exceeded and the focal length of the second lens group B2 becomes too short, it becomes easy to correct aberrations, but it is unfavorable for compactness because the amount of movement during zooming increases to ensure the desired amount of magnification.

[0038] Furthermore, when the focal length of the first lens unit B1 is f1 and the focal length of the entire system at the telephoto end is ft, it is preferable to satisfy the following conditional expression.

[0039] 0.26 <f1 / ft<0.54 ···(10) Conditional expression (10) defines, by a ratio, a preferable range between the focal length of the first lens unit B1 and the focal length of the entire system at the telephoto end. If the upper limit of conditional expression (10) is exceeded and the focal length of the first lens unit B1 becomes too long, it becomes easier to correct aberrations, but in order to ensure the desired amount of magnification, the amount of movement of the first lens unit B1 during zooming becomes too large, which is undesirable for compactness. If the lower limit of conditional expression (10) is exceeded and the focal length of the first lens unit B1 becomes too short, it becomes preferable for compactness, but it becomes difficult to correct spherical aberration, especially at the telephoto end, which is undesirable.

[0040] Furthermore, when the focal length of the second lens unit B2 is f2 and the focal length of the entire system at the wide-angle end is fw, it is preferable to satisfy the following conditional expression.

[0041] 0.72<|f2| / fw<1.67 (11) Conditional expression (11) defines, by a ratio, a preferable range of the absolute value of the focal length of the second lens unit B2 and the focal length of the entire system at the wide-angle end. If the upper limit of conditional expression (11) is exceeded and the absolute value of the focal length of the second lens unit B2 becomes too small, it becomes easier to ensure the desired amount of magnification, but it becomes difficult to correct curvature of field, particularly at the wide-angle end, which is undesirable. If the lower limit of conditional expression (11) is exceeded and the absolute value of the focal length of the second lens unit B2 becomes too large, it becomes easier to correct aberrations, but it becomes undesirable for compactness because the amount of movement during zooming increases to ensure the desired amount of magnification.

[0042] Furthermore, when the focal length of the third lens unit B3 is f3 and the focal length of the entire system at the telephoto end is ft, it is preferable to satisfy the following conditional expression.

[0043] 0.11 <f3 / ft<0.24 ···(12) Conditional expression (12) defines, by a ratio, a preferable range between the focal length of the third lens unit B3 and the focal length of the entire system at the telephoto end. If the upper limit of conditional expression (12) is exceeded and the focal length of the third lens unit B3 becomes too long, it becomes easier to correct aberrations, but in order to ensure the desired amount of magnification, the amount of movement of the first lens unit B1 during zooming becomes too large, which is undesirable for compactness. If the lower limit of conditional expression (12) is exceeded and the focal length of the third lens unit B3 becomes too short, it becomes preferable for compactness, but it becomes difficult to correct spherical aberration, especially at the telephoto end, which is undesirable.

[0044] Furthermore, it is preferable that the second lens unit B2 comprises two or more positive lenses and three or more negative lenses for good correction of lateral chromatic aberration and axial chromatic aberration.

[0045] More preferably, the second lens unit B2 includes two positive lenses and four or more negative lenses.

[0046] It is also preferable that each lens element moves along the optical axis to suppress aberration fluctuations during zooming, and it is even more preferable that all of the lens groups constituting the rear group RL move toward the object along the optical axis when zooming from the wide-angle end to the telephoto end.

[0047] Furthermore, it is preferable in terms of aberration correction that the rear group RL has a fifth lens unit B5 having positive refractive power and a seventh lens unit B7 having positive refractive power.

[0048] More preferably, the numerical ranges of the conditional expressions (1) to (12) should be set as follows:

[0049] 5.80 <f1 / |f2|<7.21 ···(1a) 0.67 <m1 / f1<1.02 ···(2a) 3.25 <fr / |f2|<5.60 ···(3a) 1.93 <f1 / f3<3.04 ···(4a) 0.28<|f2| / f3<0.45 (5a) 0.46 <f2 / ff<0.87 ···(6a) 0.75<|f2| / skw<1.37 (7a) 2.04 <f3 / skw<3.76 ···(8a) 0.21 <f2 / fsi<0.33 ···(9a) 0.31 <f1 / ft<0.46 ···(10a) 0.86<|f2| / fw<1.43 (11a) 0.13 <f3 / ft<0.20 ···(12a) It is more preferable to set the numerical ranges of the conditions (1a) to (12a) as follows:

[0050] June 18 <f1 / |f2|<6.99 ···(1b) 0.75 <m1 / f1<0.89 ···(2b) 3.66 <fr / |f2|<4.90 ···(3b) 2.18 <f1 / f3<2.66 ···(4b) 0.31<|f2| / f3<0.40 (5b) 0.52 <f2 / ff<0.76 ···(6b) 0.84<|f2| / skw<1.20 (7b) 2.30 <f3 / skw<3.29 ···(8b) 0.23 <f2 / fsi<0.29 ···(9b) 0.35 <f1 / ft<0.41 ···(10b) 0.97<|f2| / fw<1.25 (11b) 0.14 <f3 / ft<0.18 ···(12b) As described above, the zoom lens according to the embodiment of the present invention can realize a compact zoom lens that has a high zoom ratio and good optical performance over the entire zoom range from the wide-angle end to the telephoto end.

[0051] Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. [Example 1] FIG. 1 is a lens cross-sectional view of a zoom lens according to a first embodiment of the present invention at a wide-angle end (short focal length end) and at a telephoto end (long focal length end).

[0052] 2A, 2B, and 2C are aberration diagrams at the wide-angle end, at an intermediate zoom position, and at the telephoto end when the zoom lens of Example 1 is focused at infinity, respectively.

[0053] Example 1 is a zoom lens with a high zoom ratio of approximately 19x. The zoom lens of Example 1 has, in order from the object side to the image side, a first lens group B1 with positive refractive power, a second lens group B2 with negative refractive power, a third lens group B3 with positive refractive power, and a rear lens group RL further following the first lens group B1 toward the image side. The rear lens group RL has three lens groups with negative refractive power and two lens groups with positive refractive power. Specifically, the rear lens group RL has a fourth lens group B4 with negative refractive power, a fifth lens group B5 with positive refractive power, a sixth lens group B6 with negative refractive power, a seventh lens group B7 with positive refractive power, and an eighth lens group B8 with negative refractive power. During zooming, the first lens unit B1 moves toward the object side from the wide-angle end to the telephoto end, the second lens unit B2 moves toward the image side along the optical axis from the wide-angle end to the telephoto end and then moves toward the object side, and the rear unit RL also moves appropriately.

[0054] In the rear group RL, the lens group having negative refractive power closest to the aperture stop corresponds to the fourth lens group B4, and image stabilization is possible by moving the fourth lens group B4 so that it has a component perpendicular to the optical axis.

[0055] The lens unit with the strongest negative refractive power in the rear group RL corresponds to the sixth lens unit B6, and focusing is possible by moving the sixth lens unit B6 along the optical axis. The aperture stop is located between the second lens unit B2 and the third lens unit B3. [Example 2] FIG. 3 is a lens cross-sectional view of a zoom lens according to a second embodiment of the present invention at the wide-angle end (short focal length end) and at the telephoto end (long focal length end). 4A, 4B, and 4C are aberration diagrams of the zoom lens of Example 2 at the wide-angle end, at the intermediate zoom position, and at the telephoto end, respectively, when the zoom lens is focused at infinity.

[0056] Example 2 is a zoom lens with a high zoom ratio of approximately 19x. The zoom lens of Example 2 has, in order from the object side to the image side, a first lens group B1 with positive refractive power, a second lens group B2 with negative refractive power, a third lens group B3 with positive refractive power, and a rear group RL further following the first lens group B1 toward the image side. The rear group RL has two lens groups with negative refractive power and two lens groups with positive refractive power. Specifically, the rear group RL has a fourth lens group B4 with negative refractive power, a fifth lens group B5 with positive refractive power, a sixth lens group B6 with negative refractive power, and a seventh lens group B7 with positive refractive power. During zooming, the first lens unit B1 moves toward the object side from the wide-angle end to the telephoto end, the second lens unit B2 moves toward the image side along the optical axis from the wide-angle end to the telephoto end and then moves toward the object side, and the rear unit RL also moves appropriately.

[0057] In the rear group RL, the lens group having negative refractive power closest to the aperture stop corresponds to the fourth lens group B4, and image stabilization is possible by moving the fourth lens group B4 so that it has a component perpendicular to the optical axis.

[0058] The lens unit with the strongest negative refractive power in the rear group RL corresponds to the sixth lens unit B6, and focusing is possible by moving the sixth lens unit B6 along the optical axis. The aperture stop is located between the second lens unit B2 and the third lens unit B3. [Example 3] FIG. 5 is a lens cross-sectional view of a zoom lens according to a third embodiment of the present invention at the wide-angle end (short focal length end) and at the telephoto end (long focal length end).

[0059] 6A, 6B, and 6C are aberration diagrams of the zoom lens of Example 3 at the wide-angle end, at the intermediate zoom position, and at the telephoto end, respectively, when the zoom lens is focused at infinity.

[0060] Example 3 is a zoom lens with a high zoom ratio of approximately 19x. The zoom lens of Example 3 has a first lens group B1 with positive refractive power, a second lens group B2 with negative refractive power, a third lens group B3 with positive refractive power, and a rear lens group RL located further to the image side. The rear lens group RL has three lens groups with negative refractive power and three lens groups with positive refractive power. Specifically, the rear lens group RL has a fourth lens group B4 with negative refractive power, a fifth lens group B5 with positive refractive power, a sixth lens group B6 with negative refractive power, a seventh lens group B7 with positive refractive power, an eighth lens group B8 with negative refractive power, and a ninth lens group B9 with positive refractive power. During zooming, the first lens unit B1 moves toward the object side from the wide-angle end to the telephoto end, the second lens unit B2 moves toward the image side along the optical axis from the wide-angle end to the telephoto end and then moves toward the object side, and the rear unit RL also moves appropriately.

[0061] In the rear group RL, the lens group having negative refractive power closest to the aperture stop corresponds to the fourth lens group B4, and image stabilization is possible by moving the fourth lens group B4 so that it has a component perpendicular to the optical axis.

[0062] The lens unit with the strongest negative refractive power in the rear group RL corresponds to the sixth lens unit B6, and focusing is possible by moving the sixth lens unit B6 along the optical axis. The aperture stop is located between the second lens unit B2 and the third lens unit B3. [Example 4] FIG. 7 is a lens cross-sectional view of a zoom lens according to a fourth embodiment of the present invention at the wide-angle end (short focal length end) and at the telephoto end (long focal length end).

[0063] 8A, 8B, and 8C are aberration diagrams at the wide-angle end, at the intermediate zoom position, and at the telephoto end when the zoom lens of Example 4 is focused at infinity, respectively.

[0064] Example 4 is a zoom lens with a high zoom ratio of approximately 19x. The zoom lens of Example 4 has a first lens group B1 with positive refractive power, a second lens group B2 with negative refractive power, a third lens group B3 with positive refractive power, and a rear lens group RL that follows it toward the image side. The rear lens group RL has two lens groups with negative refractive power and three lens groups with positive refractive power. Specifically, the rear lens group RL has a fourth lens group B4 with negative refractive power, a fifth lens group B5 with positive refractive power, a sixth lens group B6 with negative refractive power, a seventh lens group B7 with positive refractive power, and an eighth lens group B8 with positive refractive power. During zooming, the first lens unit B1 moves toward the object side from the wide-angle end to the telephoto end, the second lens unit B2 moves toward the image side along the optical axis from the wide-angle end to the telephoto end and then moves toward the object side, and the rear unit RL also moves appropriately.

[0065] In the rear group RL, the lens group having negative refractive power closest to the aperture stop corresponds to the fourth lens group B4, and image stabilization is possible by moving the fourth lens group B4 so that it has a component perpendicular to the optical axis.

[0066] The lens unit with the strongest negative refractive power in the rear group RL corresponds to the sixth lens unit B6, and focusing is possible by moving the sixth lens unit B6 along the optical axis. The aperture stop is located between the second lens unit B2 and the third lens unit B3. [Example 5] FIG. 9 is a lens cross-sectional view of a zoom lens according to a fifth embodiment of the present invention at the wide-angle end (short focal length end) and at the telephoto end (long focal length end).

[0067] 10A, 10B, and 10C are aberration diagrams at the wide-angle end, at an intermediate zoom position, and at the telephoto end when the zoom lens of Example 5 is focused at infinity, respectively.

[0068] Example 5 is a zoom lens with a high zoom ratio of approximately 19x. The zoom lens of Example 5 has a first lens group B1 with positive refractive power, a second lens group B2 with negative refractive power, a third lens group B3 with positive refractive power, and a rear lens group RL located further to the image side. The rear lens group RL has three lens groups with negative refractive power and three lens groups with positive refractive power. Specifically, the rear lens group RL has a fourth lens group B4 with negative refractive power, a fifth lens group B5 with positive refractive power, a sixth lens group B6 with negative refractive power, a seventh lens group B7 with positive refractive power, an eighth lens group B8 with negative refractive power, and a ninth lens group B9 with positive refractive power. During zooming, the first lens unit B1 moves toward the object side from the wide-angle end to the telephoto end, the second lens unit B2 moves toward the image side along the optical axis from the wide-angle end to the telephoto end and then moves toward the object side, and the rear unit RL also moves appropriately.

[0069] In the rear group RL, the lens group having negative refractive power closest to the aperture stop corresponds to the fourth lens group B4, and image stabilization is possible by moving the fourth lens group B4 so that it has a component perpendicular to the optical axis.

[0070] The lens unit with the strongest negative refractive power in the rear group corresponds to the sixth lens unit B6, and focusing is possible by moving the sixth lens unit B6 along the optical axis. The aperture stop is located between the second lens unit B2 and the third lens unit B3.

[0071] FIG. 11 is a diagram showing lateral aberration when image stabilization is performed by decentering the fourth lens unit B4 in Example 1 of the present invention in parallel, thereby changing the angle of the optical axis on the object plane by approximately 0.4 degrees; image stabilization is also possible with the fourth lens unit B4 in the other Examples.

[0072] The zoom lens of each embodiment is a photographic lens system used in image pickup devices such as video cameras, digital still cameras, silver halide film cameras, and TV cameras.

[0073] The zoom lens of each embodiment can also be used as a projection optical system for a projection device (projector).

[0074] In the lens cross-sectional view, the left is the object side (front) and the right is the image side (rear). Also, in the lens cross-sectional view, if i is the lens group order from the object side, Bi indicates the i-th lens group. Also, in the lens cross-sectional view, the subgroups included in the first lens group B1 are, from the object side, the first subgroup B1A and the second subgroup B1B.

[0075] In addition, in the lens cross-section diagram, the focus lens group is indicated as FL, and the direction of extension from infinity to the close-up side is indicated by a dotted arrow. SP is the aperture stop. GB is an optical block equivalent to an optical filter, faceplate, low-pass filter, infrared cut filter, etc. IP is the image plane. When a zoom lens is used as the shooting optical system of a video camera or digital camera, the image plane IP corresponds to the imaging surface of an image sensor (photoelectric conversion element) such as a CCD sensor or CMOS sensor. When a zoom lens is used as the shooting optical system of a silver halide film camera, it corresponds to the film plane.

[0076] The solid arrows indicate the movement locus of each lens group when zooming from the wide-angle end to the telephoto end. The spacing between adjacent lens groups changes during zooming.

[0077] In the aberration diagrams for each example, Fno is the F-number and ω is the half angle of view (°). In the spherical aberration diagrams, the solid line is the d-line (wavelength 587.6 nm) and the two-dot chain line is the g-line (wavelength 435.8 nm). In the astigmatism diagrams, the solid line is the sagittal image plane ΔS at the d-line and the dotted line is the meridional image plane ΔM at the d-line. Distortion is shown for the d-line. Magnification chromatic aberration diagrams are shown for the g-line.

[0078] In each embodiment, the wide-angle end and the telephoto end refer to zoom positions when the zooming lens group is located at both ends of the range in which it can move mechanically on the optical axis.

[0079] The lateral aberration diagram in Figure 11, which shows aberration fluctuations while image stabilization is being performed, shows the center of the image height and the upper and lower image heights, with the solid lines indicating the meridional lateral aberration ΔM at the d-line and the dashed lines indicating the sagittal lateral aberration ΔS. The values indicated by HGT in Figure 11 correspond to off-axis image heights, with +15 mm corresponding to the upper side of the cross-sectional diagram and -15 mm corresponding to the lower side of the cross-sectional diagram. [Imaging device] Next, an embodiment of a digital camera (image capture device) that uses a zoom lens according to an embodiment of the present invention as a photographic optical system will be described with reference to Fig. 12. Fig. 12 is a schematic diagram of the main parts of a digital still camera (image capture device) that includes a zoom lens according to an embodiment of the present invention.

[0080] In Figure 12, reference numeral 20 denotes the digital camera body, 21 denotes a photographic optical system configured with the zoom lens of the above-mentioned embodiment, 22 denotes an image pickup element (photoelectric conversion element) such as a CCD that receives a subject image (image) through the photographic optical system 21, and 23 denotes recording means that records the subject image received by the image pickup element 22. 24 denotes a finder for observing the subject image displayed on a display element (not shown).

[0081] The display element is configured by a liquid crystal panel or the like, and displays the subject image formed on the image sensor 22. In this way, by applying the zoom lens according to the embodiment of the present invention to an image sensor such as a digital camera, a small-sized image sensor with high optical performance is realized.

[0082] Below, specific numerical data for Numerical Examples 1 to 5 corresponding to Examples 1 to 5, respectively, are shown. In each Numerical Example, i indicates the surface number counted from the object side. fi indicates the focal length of the ith lens group. ri is the radius of curvature of the ith optical surface (ith surface). di is the axial distance between the ith surface and the (i+1)th surface. ndi and νdi are the refractive index and Abbe number of the material of the ith optical element with respect to the d-line, respectively. The two surfaces closest to the image correspond to the glass block G. The Abbe number νd of a certain material is expressed as νd = (Nd-1) / (NF-NC), where Nd, NF, and NC are the refractive indices at the Fraunhofer d-line (587.6 nm), F-line (486.1 nm), and C-line (656.3 nm).

[0083] In each numerical example, d, focal length (mm), F-number, and half angle of view (°) are all values when the optical system of each example is focused on an object at infinity. "Back focus BF" is the distance on the optical axis from the final lens surface (the lens surface closest to the image) to the paraxial image plane, expressed as an air-equivalent length. "Total lens length" is the distance on the optical axis from the frontmost lens surface (the lens surface closest to the object) of the zoom lens to the final lens surface plus the back focus. "Wide angle" refers to the wide-angle end, "mid" refers to the intermediate zoom position, and "telephoto" refers to the telephoto end.

[0084] If the optical surface is aspherical, an asterisk (*) is added to the right of the surface number. The aspherical shape is expressed as follows: X is the displacement from the vertex of the surface in the optical axis direction, h is the height from the optical axis in the direction perpendicular to the optical axis, R is the paraxial radius of curvature, k is the conic constant, and A4, A6, A8, A10, and A12 are the aspherical coefficients of each order. x=(h 2 / R) / [1+{1-(1+k)(h / R) 2} 1 / 2 +A4×h 4 +A6×h 6 +A8×h 8 +A10×h 10 +A12×h 12 In addition, "e±XX" in each aspherical coefficient is "×10± XX " means.

[0085] [Numerical Example 1] Unit: mm Surface Data Surface number rd nd νd 1∞1.80 2 216.778 4.00 1.80610 33.3 3 132.288 11.30 1.49700 81.5 4 -3138.961 0.20 5 131.079 7.91 1.49700 81.5 6 559.185 (variable) 7 238.370 2.40 1.89190 37.1 8 30.381 10.55 9 -155.284 2.00 1.89190 37.1 10 82.883 0.20 11 68.878 9.65 1.84666 23.8 12 -58.288 0.20 13 -65.948 2.00 1.89190 37.1 14 99.320 0.20 15 63.239 6.01 1.72825 28.5 16 -237.949 2.04 1.90366 31.3 17 445.526 (variable) 18 (Aperture) ∞ 1.50 19 45.567 5.03 1.78472 25.7 20 -324.029 0.20 21 32.837 6.32 1.49700 81.5 22 -122.651 1.45 1.85478 24.8 23 32.292 (variable) 24 -97.276 4.06 1.60738 56.8 25 -28.119 1.35 1.59522 67.7 26 307.771 (variable) 27 143.558 4.16 1.72000 46.0 28 -62.468 0.20 29 53.287 6.14 1.59522 67.7 30 -44.734 1.50 1.90366 31.3 31 -337.425 (variable) 32 -88.970 5.20 1.84666 23.8 33 -24.825 1.30 1.80610 33.3 34 85.062 (variable) 35 146.359 1.60 1.80518 25.4 36 82.298 5.34 1.53172 48.8 37 -86.332 0.31 38 256.759 3.50 1.51742 52.2 39 -110.200 (variable) 40 -63.946 1.60 1.88202 37.2 41 50.834 7.21 1.74077 27.8 42 -352.595 (variable) 43 ∞ 2.00 1.51633 64.1 44 ∞ (variable) Image plane ∞ Various data Zoom ratio 19.18 Wide-angle Mid-range Telephoto Focal length 30.50 300.00 585.00 F-number 4.00 6.76 8.00 Half angle of view (°) 35.35 4.12 2.12 Image height 21.64 21.64 21.64 Lens total length 309.33 427.20 489.09 BF 29.33 69.05 102.45 d 6 1.20 130.62 149.77 d17 97.47 12.22 2.21 d23 5.35 14.21 19.89 d26 16.58 7.72 2.03 d31 2.69 7.01 2.69 d34 24.92 43.53 68.62 d39 13.37 24.43 23.01 d42 26.88 66.60 100.00 d44 1.13 1.13 1.13 Zoom lens group data Group starting plane focal length 1 1 225.80 2 7 -33.60 3 18 91.96 4 24 -128.56 5 27 42.29 6 32 -56.75 7 35 67.68 8 40 -69.76 9 43 ∞ [Numerical Example 2] Unit: mm Surface Data Surface number rd nd νd 1∞1.80 2 188.901 4.00 1.80610 33.3 3 120.086 11.40 1.49700 81.5 4 1867.591 0.20 5 134.277 8.04 1.49700 81.5 6 825.900 (variable) 7 294.228 2.40 1.88300 40.8 8 30.173 12.00 9 -76.540 2.00 1.88300 40.8 10 176.969 0.20 11 114.152 8.00 1.84666 23.8 12 -61.516 0.20 13 -77.693 2.00 1.89190 37.1 14 158.995 0.20 15 77.336 6.01 1.67270 32.1 16 -166.138 2.00 1.89190 37.1 17 -357.013 (variable) 18 (Aperture) ∞ 1.50 19 42.383 4.79 1.85478 24.8 20 5689.634 0.20 21* 35.365 5.68 1.49700 81.5 22 -218.398 1.45 1.84666 23.8 23 30.749 (variable) 24 -91.776 2.81 1.65844 50.9 25 -40.443 1.30 1.59522 67.7 26 349.809 (variable) 27 118.743 3.98 1.69100 54.8 28 -75.539 0.20 29 58.391 6.32 1.59522 67.7 30 -40.419 1.50 1.90366 31.3 31 -151.366 (variable) 32 -109.232 5.20 1.90366 31.3 33 -24.664 1.30 1.85150 40.8 34 87.557 (variable) 35 119.777 1.60 1.84666 23.8 36 74.154 5.70 1.53172 48.8 37 -143.703 0.20 38 452.277 3.50 1.51823 58.9 39 -91.835 10.96 40 -73.186 1.60 1.85150 40.8 41 45.093 6.28 1.74077 27.8 42 -352.595 (variable) 43 ∞ 2.00 1.51633 64.1 44 ∞ (variable) Image plane ∞ Aspheric data Page 21 K = 0.00000e+000 A 4=-5.87534e-007 A 6=-3.33478e-010 A 8=-1.17968e-012 Various data Zoom ratio 19.18 Wide-angle Mid-range Telephoto Focal length 30.50 302.00 585.00 F-number 4.00 6.76 8.00 Half angle of view (°) 35.35 4.10 2.12 Image height 21.64 21.64 21.64 Lens total length 309.33 431.61 489.33 BF 35.46 94.70 102.45 d 6 1.20 126.39 144.72 d17 97.23 17.29 2.00 d23 5.76 19.65 24.16 d26 20.41 6.52 2.00 d31 2.22 4.14 2.36 d34 20.54 36.39 85.10 d42 33.01 92.26 100.00 d44 1.13 1.13 1.13 Zoom lens group data Group starting plane focal length 1 1 222.09 2 7 -36.40 3 18 98.44 4 24 -136.57 5 27 42.90 6 32 -62.12 7 35 312.95 8 43 ∞ [Numerical Example 3] Unit: mm Surface Data Surface number rd nd νd 1∞1.80 2 223.463 4.00 1.80610 33.3 3 133.187 11.47 1.49700 81.5 4 -1959.031 0.20 5 126.710 8.05 1.49700 81.5 6 530.754 (variable) 7 189.567 2.40 1.88300 40.8 8 28.256 11.35 9 -124.138 2.00 1.88300 40.8 10 122.879 0.20 11 64.284 8.71 1.84666 23.8 12 -74.483 0.20 13 -79.390 2.00 1.89190 37.1 14 98.962 0.20 15 70.205 6.01 1.67270 32.1 16 -150.639 2.00 1.89190 37.1 17 902.370 (variable) 18 (Aperture) ∞ 1.50 19 52.534 4.42 1.85478 24.8 20 -373.094 0.20 21* 34.325 6.56 1.49700 81.5 22 -183.232 1.82 1.84666 23.8 23 34.368 (variable) 24 -93.156 2.84 1.65844 50.9 25 -40.085 1.30 1.59522 67.7 26 297.349 (variable) 27 216.877 3.68 1.69100 54.8 28 -67.658 0.20 29 47.104 6.62 1.59522 67.7 30 -42.486 1.50 1.90366 31.3 31 -153.552 (variable) 32 -106.102 5.07 1.90366 31.3 33 -24.067 1.30 1.85150 40.8 34 73.203 (variable) 35 327.023 1.60 1.84666 23.8 36 150.439 3.57 1.53172 48.8 37 -119.144 0.20 38 148.328 3.50 1.51823 58.9 39 -169.036 (variable) 40 -145.716 1.60 1.83400 37.3 41 41.303 3.91 1.74077 27.8 42 119.417 (variable) 43 136.097 1.60 1.90366 31.3 44 49.860 4.96 1.74077 27.8 45 -838.454 (variable) 46 ∞ 2.00 1.51633 64.1 47 ∞ (variable) Image plane ∞ Aspheric data Page 21 K = 0.00000e+000 A 4=-9.09245e-008 A 6= 1.13476e-010 A 8=-6.46254e-013 Various data Zoom ratio 19.18 Wide-angle Mid-range Telephoto Focal length 30.50 302.00 585.00 F-number 4.00 6.76 8.00 Half angle of view (°) 35.35 4.10 2.12 Image height 21.64 21.64 21.64 Lens total length 311.33 424.37 487.84 BF 36.69 74.87 96.76 d 6 1.20 124.37 145.66 d17 95.86 9.66 3.11 d23 5.92 19.85 26.23 d26 22.44 8.51 2.13 d31 2.25 3.60 2.25 d34 18.66 27.29 63.88 d39 7.65 32.31 22.77 d42 2.14 5.39 6.53 d45 34.26 72.43 94.33 d47 1.12 1.12 1.12 Zoom lens group data Group starting plane focal length 1 1 221.60 2 7 -32.93 3 18 87.50 4 24 -133.21 5 27 40.75 6 32 -54.80 7 35 87.57 8 40 -69.75 9 43 234.68 10 46 ∞ [Numerical Example 4] Unit: mm Surface Data Surface number rd nd νd 1∞1.80 2 194.406 4.00 1.80610 33.3 3 124.165 11.36 1.49700 81.5 4 6070.305 0.20 5 135.830 8.19 1.49700 81.5 6 665.019 (variable) 7 268.674 2.40 1.89190 37.1 8 30.253 11.04 9 -115.334 2.00 1.89190 37.1 10 97.319 0.20 11 74.522 9.85 1.84666 23.8 12 -53.753 0.21 13 -57.436 2.00 1.85150 40.8 14 109.786 0.21 15 70.054 6.01 1.64769 33.8 16 -181.773 2.00 1.90366 31.3 17 -504.471 (variable) 18 (Aperture) ∞ 1.50 19 43.992 4.79 1.78472 25.7 20 -669.611 0.20 21 32.308 6.08 1.49700 81.5 22 -193.258 1.45 1.85478 24.8 23 31.277 (variable) 24 -95.631 2.99 1.65100 56.2 25 -38.121 1.30 1.59522 67.7 26 247.918 (variable) 27 126.296 3.98 1.72000 46.0 28 -68.604 0.20 29 50.825 6.32 1.59522 67.7 30 -40.817 1.50 1.90366 31.3 31 -226.260 (variable) 32 -80.833 5.20 1.84666 23.8 33 -22.584 1.30 1.80610 33.3 34 68.959 (variable) 35 148.711 1.60 1.80518 25.4 36 89.855 5.66 1.53172 48.8 37 -66.961 0.20 38 254.798 3.50 1.69350 50.8 39 -111.810 10.06 40 -76.621 1.60 1.89190 37.1 41 53.698 3.33 1.74077 27.8 42 147.053 (variable) 43 209.982 1.60 1.85883 30.0 44 61.738 4.47 1.74077 27.8 45 -401.314 (variable) 46 ∞ 2.00 1.51633 64.1 47 ∞ (variable) Image plane ∞ Various data Zoom ratio 19.18 Wide-angle Mid-range Telephoto Focal length 30.50 302.00 585.00 F-number 4.00 6.76 8.00 Half angle of view (°) 35.35 4.10 2.12 Image height 21.64 21.64 21.64 Lens total length 311.33 428.68 485.25 BF 34.87 79.87 100.91 d 6 1.20 130.90 147.97 d17 97.73 16.40 2.00 d23 5.55 15.73 19.58 d26 16.03 5.85 2.00 d31 2.63 7.22 3.89 d34 20.89 32.28 41.83 d42 2.15 10.15 36.77 d45 32.42 77.43 98.47 d47 1.13 1.13 1.13 Zoom lens group data Group starting plane focal length 1 1 223.82 2 7 -35.08 3 18 94.97 4 24 -128.75 5 27 40.99 6 32 -48.23 7 35 249.80 8 43 249.16 9 46 ∞ [Numerical Example 5] Unit: mm Surface Data Surface number rd nd νd 1∞1.80 2 223.328 4.00 1.80610 33.3 3 132.423 11.89 1.49700 81.5 4 -1247.019 0.20 5 122.522 8.19 1.49700 81.5 6 499.314 (variable) 7 187.138 2.40 1.89190 37.1 8 27.309 10.60 9 -142.381 2.00 1.89190 37.1 10 124.731 0.20 11 58.038 9.59 1.84666 23.8 12 -55.640 0.70 13 -50.906 2.01 1.89190 37.1 14 119.208 0.20 15 67.622 6.01 1.72825 28.5 16 -107.389 2.01 1.90366 31.3 17 249.755 (variable) 18 (Aperture) ∞ 1.50 19 48.129 4.04 1.78472 25.7 20 -1118.112 0.20 21* 26.402 5.86 1.49700 81.5 22 785.851 2.38 1.85478 24.8 23 26.820 (variable) 24 -98.798 3.83 1.60738 56.8 25 -28.130 1.30 1.59522 67.7 26 282.952 (variable) 27 105.994 3.98 1.72000 46.0 28 -68.403 0.20 29 51.096 6.32 1.59522 67.7 30 -37.214 1.50 1.90366 31.3 31 -155.337 (variable) 32 -98.441 4.86 1.84666 23.8 33 -21.653 1.30 1.80610 33.3 34 76.500 (variable) 35 97.831 1.60 1.80518 25.4 36 51.214 4.96 1.53172 48.8 37 -202.579 0.20 38 95.176 3.50 1.51633 64.1 39 -244.547 (variable) 40 912.738 1.60 1.90366 31.3 41 42.335 1.77 1.74077 27.8 42 48.385 (variable) 43 128.540 1.60 1.53775 74.7 44 42.172 5.08 1.74077 27.8 45 444.091 (variable) 46 ∞ 2.00 1.51633 64.1 47 ∞ (variable) Image plane ∞ Aspheric data Page 21 K = 0.00000e+000 A 4=-1.50048e-007 A 6= 2.39227e-010 A 8= 1.03096e-012 Various data Zoom ratio 19.20 Wide-angle Mid-range Telephoto Focal length 30.50 300.82 585.58 F-number 4.00 6.76 8.00 Half angle of view (°) 35.35 4.11 2.12 Image height 21.64 21.64 21.64 Lens total length 289.33 402.18 469.33 BF 35.16 78.40 97.38 d 6 1.20 121.18 140.76 d17 82.16 8.59 2.79 d23 5.50 14.07 16.99 d26 13.49 4.92 2.00 d31 2.28 5.17 4.43 d34 21.20 21.20 61.71 d39 5.14 20.71 7.87 d42 3.82 8.56 16.02 d45 32.71 75.95 94.93 d47 1.13 1.13 1.13 Zoom lens group data Group starting plane focal length 1 1 211.86 2 7 -30.63 3 18 93.83 4 24 -127.34 5 27 37.97 6 32 -57.11 7 35 77.77 8 40 -54.96 9 43 135.88 10 46 ∞ Table 1 shows the relationship between the above-mentioned conditional expressions and numerical examples.

[0086] [Table 1]

[0087] 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]

[0088] B1...First lens group B2: Second lens group B3: Third lens group RL…Rear group

Claims

1. A zoom lens comprising, arranged 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, a third lens group having a positive refractive power, and a rear group including a plurality of lens groups, wherein the spacing between adjacent lens groups changes during zooming, the rear group includes a plurality of lens groups having negative refractive power and a plurality of lens groups having positive refractive power, During zooming from the wide-angle end to the telephoto end, the first lens group moves toward the object side, and the second lens group moves toward the image side and then moves toward the object side, the first lens group comprises, in order from the object side to the image side, a negative lens, a positive lens, and a positive lens; Let f1 be the focal length of the first lens group, f2 be the focal length of the second lens group, m1 be the movement amount of the first lens group during zooming from the wide-angle end to the telephoto end, fr be the composite focal length of the rear lens group at the wide-angle end, the zoom lens has an aperture stop, and fsi be the focal length of the lens group in the rear lens group that has negative refractive power and is closest to the aperture stop. 5.50<f1 / |f2|<7.50 0.56<m1 / f1<1.19 2.71<fr / |f2|<6.53 0.17<f2 / fsi<0.38 A zoom lens characterized by satisfying the following conditional expressions:

2. When the focal length of the third lens group is f3, 1.61<f1 / f3<3.55 2. The zoom lens according to claim 1, wherein the following condition is satisfied:

3. When the focal length of the third lens group is f3, 0.23<|f2| / f3<0.53 3. The zoom lens according to claim 1, wherein the following condition is satisfied:

4. When the focal length of the lens group having the smallest absolute value of the focal length among the plurality of lens groups having negative refractive power is ff, 0.38<f2 / ff<1.02 4. The zoom lens according to claim 1, wherein the following condition is satisfied:

5. When the back focus at the wide-angle end is skw, 0.62<|f2| / skw<1.60 5. The zoom lens according to claim 1, wherein the following condition is satisfied:

6. When the focal length of the third lens group is f3 and the back focus at the wide-angle end is skw, 1.70<f3 / skw<4.39 6. The zoom lens according to claim 1, wherein the following condition is satisfied:

7. When the focal length of the zoom lens at the telephoto end is ft, 0.26<f1 / ft<0.54 7. The zoom lens according to claim 1, wherein the following condition is satisfied:

8. When the focal length of the zoom lens at the wide-angle end is fw, 0.72<|f2| / fw<1.67 8. The zoom lens according to claim 1, wherein the following condition is satisfied:

9. When the focal length of the third lens group is f3 and the focal length of the zoom lens at the telephoto end is ft, 0.11<f3 / ft<0.24 9. The zoom lens according to claim 1, wherein the following condition is satisfied:

10. 10. The zoom lens according to claim 1, wherein the lens group having negative refractive power in the rear group that is closest to the aperture stop moves in a direction that includes a component perpendicular to the optical axis during image blur correction.

11. 5. The zoom lens according to claim 4, wherein the lens group having the smallest absolute value of the focal length among the plurality of lens groups having negative refractive powers moves during focusing.

12. 12. The zoom lens according to claim 1, wherein all lens units constituting the rear group move toward the object side during zooming from the wide-angle end to the telephoto end.

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

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

15. 13. The zoom lens according to claim 1, wherein the rear group consists of, arranged in order from the object side to the image side, a fourth lens group having negative refractive power, a fifth lens group having positive refractive power, a sixth lens group having negative refractive power, a seventh lens group having positive refractive power, an eighth lens group having negative refractive power, and a ninth lens group having positive refractive power.

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

17. 17. The zoom lens according to claim 13, wherein the zoom lens has an aperture stop, and the fourth lens group is disposed in the rear group at a position closest to the aperture stop.

18. 18. The zoom lens according to claim 13, wherein the sixth lens group has the smallest absolute value of the focal length among the plurality of lens groups each having a negative refractive power.

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

Images