Zoom lens and camera device

Abstract

This invention provides a zoom lens with anti-vibration properties, which facilitates miniaturization and weight reduction while maintaining good optical performance, and a camera device equipped with the zoom lens. The zoom lens, from the object side towards the image side, sequentially comprises a first lens group with positive refractive power, a second lens group with negative refractive power, an intermediate group with positive refractive power, and a subsequent group with negative refractive power. The first lens group moves during zooming. The second lens group, from the object side towards the image side, sequentially includes a front group of the second lens group that remains stationary during image shake correction and an anti-vibration group with negative refractive power that moves during image shake correction. The zoom lens satisfies a predetermined conditional expression.

Description

Technical Field

[0001] The present invention relates to a zoom lens and a camera device. Background Technology

[0002] As zoom lenses applicable to imaging devices such as digital cameras and camcorders, the lens systems described in Patent Document 1 and Patent Document 2 below are known.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2019-053122

[0004] Patent Document 2: Japanese Patent Application Publication No. 2015-191008

[0005] In recent years, there has been a demand for zoom lenses that are shock-resistant, compact and lightweight, and maintain good optical performance. Summary of the Invention

[0006] The present invention was made in view of the above circumstances, and its object is to provide a zoom lens with anti-vibration performance, which is conducive to miniaturization and weight reduction and maintains good optical performance, and a camera device having the zoom lens.

[0007] The zoom lens of the present invention, from the object side toward the image side, sequentially comprises a first lens group with positive refractive power, a second lens group with negative refractive power arranged continuously with the first lens group, an intermediate group with positive refractive power including at least one lens group, and a subsequent group with negative refractive power including at least one lens group. During zooming, the first lens group moves along the optical axis, the interval between the first and second lens groups changes, the interval between the second and intermediate lens groups changes, and the interval between the intermediate and subsequent groups changes. The second lens group, from the object side toward the image side, sequentially comprises a front group of the second lens group fixed during image shake correction and an image... For example, a vibration-damping assembly with negative refractive power that moves along the direction intersecting the optical axis during shake correction is defined as follows: DL1 is set as the difference in the optical axis between the positions of the first lens group at the telephoto end and the first lens group at the wide-angle end; Lw is set as the distance along the optical axis from the lens surface closest to the object at the wide-angle end to the lens surface closest to the image at the wide-angle end; isit is set as the lateral magnification of the vibration-damping assembly at the telephoto end when focusing on an object at infinity; and isrt is set as the combined lateral magnification of all lenses closer to the image side than the vibration-damping assembly at the telephoto end when focusing on an object at infinity.

[0008] The zoom lens satisfies the following conditions (1) and (2).

[0009] 0.4 < DL1 / Lw < 1 (1),

[0010] 3.5<|(1-βist)×βisrt|<7 (2).

[0011] The intermediate group can be configured to include, from the object side toward the image side, an intermediate group A with positive refractive power and an intermediate group B with positive refractive power, and the interval between the intermediate group A and the intermediate group B changes during zooming. In this case, it is preferable that only the intermediate group B moves along the optical axis during focusing.

[0012] In a structure where only the middle B group moves along the optical axis during focusing, if the focal length of the middle A group is set to fmA and the focal length of the middle B group is set to fmB...

[0013] The zoom lens preferably satisfies the following condition (3).

[0014] 0.5 < fmA / fmB < 2 (3).

[0015] In a structure where only the middle B group moves along the optical axis during focusing, with the focal length at the telephoto end (focusing on an object at infinity) set to DmAB, the optical axis spacing between the middle A group and the middle B group is set to fmB.

[0016] The zoom lens preferably satisfies the following condition (4).

[0017] 0.3 < DmAB / fmB < 1 (4).

[0018] In a structure where only the middle B group moves along the optical axis during focusing, with the lateral magnification of the middle B group at the telephoto end when focusing on an object at infinity set to βmBt, and the combined lateral magnification of all lenses further from the image side than the middle B group at the telephoto end when focusing on an object at infinity set to βmBrt.

[0019] The zoom lens preferably satisfies the following condition (5).

[0020] 3<|(1-mBt 2 )×βmBrt 2 |<10 (5).

[0021] With the distance on the optical axis from the lens surface closest to the object in the entire system at the telephoto end to the lens surface closest to the object in the anti-vibration group at the telephoto end set to Llist, and the focal length of the first lens group set to f1,

[0022] The zoom lens preferably satisfies the following condition (6).

[0023] 0.57 < Llist / f1 < 0.7 (6).

[0024] Preferably, the front group of the second lens group has positive refractive power.

[0025] With the focal length of the entire system set to fw at the wide-angle end while focusing on an object at infinity, and the focal length of the vibration damping group set to fis,

[0026] The zoom lens preferably satisfies the following condition (7).

[0027] 1 < fw / |fis| < 5 (7).

[0028] With the focal length of the entire system at the wide-angle end set to fw when focusing on an object at infinity, and the focal length of the intermediate group at the wide-angle end set to fmw when focusing on an object at infinity,

[0029] The zoom lens preferably satisfies the following condition (8),

[0030] 1 < fw / fmw < 5 (8).

[0031] With the focal length of the entire system at the telephoto end (focusing on an object at infinity) set to ft, and the focal length of the intermediate group at the telephoto end (focusing on an object at infinity) set to fmt,

[0032] The zoom lens preferably satisfies the following condition (9).

[0033] 5 < ft / fmt < 10 (9).

[0034] When the focal length of the middle group at the telephoto end is set to fmt when focusing on an object at infinity, and the focal length of the middle group at the wide-angle end is set to fmw when focusing on an object at infinity,

[0035] The zoom lens preferably satisfies the following condition (10).

[0036] 0.8 < fmt / fmw < 1.8 (10).

[0037] With the focal length of the entire system at the wide-angle end set to fw when focusing on an object at infinity, and the focal length of the lens group with the strongest negative refractive power in the subsequent group set to fsmax, the following conditions are met.

[0038] The zoom lens preferably satisfies the following condition (11),

[0039] 1 < fw / |fsmax| < 4 (11).

[0040] Preferably, the subsequent groups sequentially include a lens group with negative refractive power and a lens group with positive refractive power from the object side toward the image side, and the interval between the lens group with negative refractive power and the lens group with positive refractive power changes during zooming.

[0041] Preferably, an aperture is arranged between the second lens group and the intermediate lens group.

[0042] With the focal length of the entire system at the telephoto end (focusing on an object at infinity) set to ft, and the focal length of the entire system at the wide-angle end (focusing on an object at infinity) set to fw,

[0043] The zoom lens preferably satisfies the following condition (12),

[0044] 3 < ft / fw < 5 (12).

[0045] With the distance along the optical axis from the lens surface closest to the object to the lens surface closest to the image in the wide-angle end of the entire system set to Lw, and the focal length of the entire system at the wide-angle end when focusing on an object at infinity set to fw, the following conditions are met.

[0046] The zoom lens preferably satisfies the following condition (13).

[0047] 1.3 < Lw / fw < 1.6 (13).

[0048] With the back focal length of the entire system's air-to-ground distance meter set to Bfw at the wide-angle end while focusing on an object at infinity, and the focal length of the entire system's wide-angle end set to fw while focusing on an object at infinity,

[0049] The zoom lens preferably satisfies the following condition (14).

[0050] 0.35 < Bfw / fw < 0.55 (14).

[0051] The preferred subsequent group includes a lens group that is fixed relative to the image plane when zooming, on the image side closest to the image.

[0052] The camera device of the present invention includes the zoom lens of the present invention.

[0053] In addition, the terms "including" and "including" in this specification mean that, in addition to the constituent elements listed, it may also include lenses that do not substantially have refractive power, as well as optical elements other than lenses such as apertures, filters and cover glass, and mechanism parts such as lens flanges, lens barrels, imaging elements and hand shaking correction mechanisms.

[0054] In this specification, "a group with positive refractive power" means that the group as a whole has positive refractive power. Similarly, "a group with negative refractive power" means that the group as a whole has negative refractive power. "A lens with positive refractive power" and "a positive lens" have the same meaning. "A lens with negative refractive power" and "a negative lens" have the same meaning. "A lens group" is not limited to a structure that includes multiple lenses; it can also be a structure that includes only one lens.

[0055] A compound aspherical lens (a lens in which a spherical lens and an aspherical film formed on the spherical lens are integrated to function as a single aspherical lens) is used as a single lens and not considered as a combined lens. Unless otherwise specified, the sign of the refractive power and the surface shape associated with lenses including aspherical surfaces are assumed to be considered in the paraxial region.

[0056] In this specification, "the entire system" refers to the zoom lens. "Back focal length of the air-converted distance meter" is the air-converted distance along the optical axis from the image-side lens surface to the image plane of the entire system when focused on an object at infinity. "Focal length" used in the conditional formulas refers to the paraxial focal length. The values ​​used in the conditional formulas are values ​​with the d-line as a reference when focused on an object at infinity. The "d-line," "C-line," "F-line," and "g-line" described in this specification are bright lines. In this specification, the wavelength of the d-line is considered to be 587.56 nm, the wavelength of the C-line is considered to be 656.27 nm, the wavelength of the F-line is considered to be 486.13 nm, and the wavelength of the g-line is considered to be 435.84 nm.

[0057] Invention Effects

[0058] According to the present invention, a zoom lens with anti-vibration properties, which is conducive to miniaturization and weight reduction, and which maintains good optical performance, and a camera device having the zoom lens can be provided. Attached Figure Description

[0059] Figure 1 This is a cross-sectional view showing the structure and direction of movement of the zoom lens in Embodiment 1.

[0060] Figure 2 This is a cross-sectional view showing the structure and beam of the zoom lens in various zoom states of Embodiment 1.

[0061] Figure 3 These are aberration diagrams of the zoom lens in Example 1.

[0062] Figure 4 This is a cross-sectional view showing the structure and direction of movement of the zoom lens in Embodiment 2.

[0063] Figure 5 These are aberration diagrams of the zoom lens in Example 2.

[0064] Figure 6 This is a cross-sectional view showing the structure and direction of movement of the zoom lens in Embodiment 3.

[0065] Figure 7 These are aberration diagrams of the zoom lens in Example 3.

[0066] Figure 8 This is a cross-sectional view showing the structure and direction of movement of the zoom lens in Embodiment 4.

[0067] Figure 9 These are aberration diagrams of the zoom lens in Example 4.

[0068] Figure 10 This is a cross-sectional view showing the structure and direction of movement of the zoom lens in Embodiment 5.

[0069] Figure 11 These are aberration diagrams of the zoom lens in Example 5.

[0070] Figure 12 This is a perspective view of the front side of a camera device according to one embodiment.

[0071] Figure 13 This is a perspective view of the rear side of a camera device according to one embodiment. Detailed Implementation

[0072] The embodiments of the present invention will now be described. One embodiment of the zoom lens according to the present invention comprises, from the object side toward the image side, a first lens group having positive refractive power, a second lens group having negative refractive power arranged sequentially with the first lens group, an intermediate group having positive refractive power including at least one lens group, and a subsequent group having negative refractive power including at least one lens group. When zooming from a wide-angle end to a telephoto end, the first lens group moves along the optical axis, the interval between the first lens group and the second lens group changes, the interval between the second lens group and the intermediate group changes, and the interval between the intermediate group and the subsequent group changes. By adopting this structure, zooming from a wide-angle end to a telephoto end can be easily achieved, and even in this zoomed state, it is easy to construct a compact design, and it is easy to suppress aberrations accompanying zooming.

[0073] Additionally, the term "lens group" in this specification refers to a component of a zoom lens, which includes at least one lens separated by an air gap that changes during zooming.

[0074] When zooming, the lens group is moved or fixed in units, and the spacing between the lenses within a lens group remains unchanged.

[0075] The second lens group, from the object side to the image side, consists of a front group of the second lens group fixed during image jitter correction and an anti-vibration group with negative refractive power that moves along the direction intersecting the optical axis during image jitter correction. By designating only a portion of the second lens group as the anti-vibration group, rather than the entire second lens group, the refractive powers of the entire second lens group and the anti-vibration group can be made different from each other. This makes it easier to control the refractive power of the anti-vibration group, which is beneficial for balancing good anti-vibration performance with miniaturization of the anti-vibration group.

[0076] Preferably, the front group of the second lens group has positive refractive power. In this case, the diameter of the beam incident on the anti-vibration group can be reduced, thus facilitating the miniaturization of the anti-vibration unit. Furthermore, when the front group of the second lens group has positive refractive power, it is easier to enhance the negative refractive power of the anti-vibration group, thus helping to shorten the movement of the anti-vibration group during image jitter correction.

[0077] The intermediate group can be configured such that, from the object side toward the image side, it includes an intermediate group A with positive refractive power and an intermediate group B with positive refractive power. During zooming, the interval between intermediate group A and intermediate group B changes. In this case, intermediate group A and intermediate group B can share the positive refractive power of the intermediate group, thus helping to suppress changes in spherical aberration during zooming.

[0078] When the intermediate group includes the aforementioned intermediate group A and intermediate group B, it is preferable that only intermediate group B moves along the optical axis during focusing. Hereinafter, the group that moves during focusing will be referred to as the focusing group. When intermediate group B is set as the focusing group, the focusing group will be located adjacent to the image side of intermediate group A, which has positive refractive power, thus facilitating the miniaturization of the focusing group.

[0079] Next, preferred structures related to the conditional expressions will be described. However, the conditional expressions preferably satisfied by the zoom lens of the present invention are not limited to those described in formula form, but also include all conditional expressions obtained by arbitrarily combining the lower and upper limits from the preferred and more preferred conditional expressions. In the following description of preferred and achievable structures, the zoom lens of the present invention will also be referred to as a zoom lens.

[0080] With the optical axis difference between the position of the first lens group at the telephoto end and the position of the first lens group at the wide-angle end set to DL1, and the optical axis distance from the lens surface closest to the object side of the entire system at the wide-angle end to the lens surface closest to the image side of the entire system at the wide-angle end set to Lw, the zoom lens preferably satisfies the following condition (1). By ensuring that the corresponding value of condition (1) is not below the lower limit, the movement of the first lens group during zooming will not become too small, thus facilitating a high zoom ratio. By ensuring that the corresponding value of condition (1) is not above the upper limit, the movement of the first lens group during zooming will not become too large, thus facilitating a shorter overall length, and also facilitating miniaturization and weight reduction. By satisfying condition (1), it is advantageous to achieve a small and lightweight structure while obtaining a high zoom ratio. To obtain even better characteristics, the zoom lens more preferably satisfies the following condition (1-1).

[0081] 0.4 < DL1 / Lw < 1 (1)

[0082] 0.5 < DL1 / Lw < 0.85 (1-1)

[0083] When the lateral magnification of the anti-vibration group at the telephoto end, focused on an object at infinity, is set to βist, and the combined lateral magnification of all lenses closer to the image side than the anti-vibration group at the telephoto end, focused on an object at infinity, is set to βisrt, the zoom lens preferably satisfies the following condition (2). By ensuring that the corresponding value of condition (2) is not below the lower limit, the movement of the anti-vibration group during image shake correction will not become excessive, thus facilitating miniaturization. By ensuring that the corresponding value of condition (2) is not above the upper limit, the positional accuracy of the anti-vibration group during image shake correction will not become overly sensitive, thus making it easy to control. Satisfying condition (2) facilitates miniaturization of the anti-vibration unit and ensures appropriate anti-vibration performance. To obtain even better characteristics, the zoom lens more preferably satisfies the following condition (2-1).

[0084] 3.5<|(1-βist)×βisrt|<7 (2)

[0085] 3.5<|(1-βist)×βisrt|<5.5 (2-1)

[0086] In a structure where the intermediate group includes the aforementioned intermediate A group and intermediate B group, and the focusing group includes the intermediate B group, when the focal length of the intermediate A group is set to fmA and the focal length of the intermediate B group is set to fmB, the zoom lens preferably satisfies the following condition (3). By ensuring that the corresponding value of condition (3) is not below the lower limit, the movement of the focusing group during focusing will not become excessive, thus facilitating a reduction in the overall length. By ensuring that the corresponding value of condition (3) is not above the upper limit, it is beneficial to suppress variations in spherical aberration during focusing. By satisfying condition (3), it is beneficial to reduce the overall length and suppress spherical aberration. To obtain even better characteristics, the zoom lens more preferably satisfies the following condition (3-1).

[0087] 0.5 < fmA / fmB < 2 (3)

[0088] 0.8 < fmA / fmB < 1.2 (3-1)

[0089] In a structure where the intermediate group includes the aforementioned intermediate A group and intermediate B group, and the focusing group includes intermediate B group, when the distance on the optical axis between intermediate A group and intermediate B group at the telephoto end with the focus on an object at infinity is set to DmAB, and the focal length of intermediate B group is set to fmB, the zoom lens preferably satisfies the following conditional expression (4). By ensuring that the corresponding value of conditional expression (4) is not below the lower limit, DmAB will not become too narrow compared to the refractive power of intermediate B group, thus facilitating close-up photography. By ensuring that the corresponding value of conditional expression (4) is not above the upper limit, DmAB will not become too wide compared to the refractive power of intermediate B group, thus facilitating miniaturization. By satisfying conditional expression (4), it is beneficial to shorten the minimum shooting distance and miniaturize the lens. To obtain better characteristics, the zoom lens more preferably satisfies the following conditional expression (4-1).

[0090] 0.3 < DmAB / fmB < 1 (4)

[0091] 0.35 < DmAB / fmB < 0.7 (4-1)

[0092] In a structure where the intermediate group includes the aforementioned intermediate A group and intermediate B group, and the focusing group includes intermediate B group, when the lateral magnification of intermediate B group at the telephoto end with the object at infinity is set to mB t, and the combined lateral magnification of all lenses closer to the image side than intermediate B group at the telephoto end with the object at infinity is set to βmBrt, the zoom lens preferably satisfies the following conditional expression (5). By ensuring that the corresponding value of conditional expression (5) is not below the lower limit, the amount of movement of the focusing group when focusing towards the closer distance will not become too large, thus facilitating miniaturization. By ensuring that the corresponding value of conditional expression (5) is not above the upper limit, the positional accuracy of the focusing group during focusing will not become too sensitive, thus making it easy to control. By satisfying conditional expression (5), miniaturization of the focusing unit and shortening of the minimum shooting distance are beneficial. To obtain better characteristics, the zoom lens more preferably satisfies the following conditional expression (5-1).

[0093] 3<|(1-βmBt 2 )×βmBrt 2 |<10 (5)

[0094] 5<|(1-βmBt 2 )×βmBrt 2 |<7 (5-1)

[0095] With the distance on the optical axis from the lens surface closest to the object in the entire system at the telephoto end to the lens surface closest to the object in the anti-vibration group at the telephoto end set to L1ist, and the focal length of the first lens group set to f1, the zoom lens preferably satisfies the following condition (6). By ensuring that the corresponding value of condition (6) is not below the lower limit, the refractive power of the first lens group will not become too weak, thus making it particularly possible to reduce the diameter of the beam incident on the anti-vibration group at the telephoto end, thereby facilitating the miniaturization of the anti-vibration unit. By ensuring that the corresponding value of condition (6) is not above the upper limit, it is beneficial to shorten the overall length or to easily correct various aberrations in the entire system, especially spherical aberrations. Satisfying condition (6) facilitates miniaturization and aberration correction. To obtain better characteristics, the zoom lens more preferably satisfies the following condition (6-1).

[0096] 0.57 < Llist / f1 < 0.7 (6)

[0097] 0.58 < Llist / f1 < 0.67 (6-1)

[0098] When the focal length of the entire system at the wide-angle end is set to fw and the focal length of the image stabilization unit is set to fis, the zoom lens preferably satisfies the following condition (7). By ensuring that the corresponding value of condition (7) is not below the lower limit, the movement of the image stabilization unit during image shake correction will not become too large, thus facilitating miniaturization. By ensuring that the corresponding value of condition (7) is not above the upper limit, the positional accuracy of the image stabilization unit during image shake correction will not become too sensitive, thus making it easy to control. Satisfying condition (7) facilitates the miniaturization of the image stabilization unit and ensures appropriate image stabilization performance. To obtain even better characteristics, the zoom lens more preferably satisfies the following condition (7-1).

[0099] 1 < fw / fis | < 5 (7)

[0100] 2 < fw / fis| < 4 (7-1)

[0101] When the focal length of the entire system at the wide-angle end with the object focused at infinity is set to fw, and the focal length of the intermediate group at the wide-angle end with the object focused at infinity is set to fmw, the zoom lens preferably satisfies the following condition (8). By ensuring that the corresponding value of condition (8) is not below the lower limit, the large diameter of the beam incident on subsequent groups can be suppressed, thus facilitating small diameter reduction. By ensuring that the corresponding value of condition (8) is not above the upper limit, aberration changes during zooming are easily suppressed. By satisfying condition (8), small diameter reduction and suppression of aberration changes during zooming are beneficial. To obtain even better characteristics, the zoom lens more preferably satisfies the following condition (8-1).

[0102] 1 < fw / fmw < 5 (8)

[0103] 2 < fw / fmw < 3.5 (8-1)

[0104] When the focal length of the entire system at the telephoto end with the object focused at infinity is set to ft, and the focal length of the intermediate group at the telephoto end with the object focused at infinity is set to fmt, the zoom lens preferably satisfies the following condition (9). By ensuring that the corresponding value of condition (9) is not below the lower limit, the large diameter of the beam incident on subsequent groups can be suppressed, thus facilitating small diameter reduction. By ensuring that the corresponding value of condition (9) is not above the upper limit, aberration changes during zooming are easily suppressed. By satisfying condition (9), small diameter reduction and suppression of aberration changes during zooming are beneficial. To obtain even better characteristics, the zoom lens more preferably satisfies the following condition (9-1).

[0105] 5 < ft / fmt < 10 (9)

[0106] 6.5 < ft / fmt < 8.5 (9-1)

[0107] When the focal length of the intermediate group at the wide-angle end is set to fmw when focusing on an object at infinity, and the focal length of the intermediate group at the telephoto end is set to fmt when focusing on an object at infinity, the zoom lens preferably satisfies the following condition (10). By ensuring that the corresponding value of condition (10) does not fall below the lower limit, it is beneficial to suppress aberrations on the telephoto side during zooming.

[0108] By ensuring that the corresponding value of condition (10) does not exceed the upper limit, it is beneficial to suppress aberration variations on the wide-angle side during zooming. By satisfying condition (10), it is beneficial to suppress aberration variations during zooming. To obtain better characteristics, zoom lenses are more preferably satisfied with the following condition (10-1).

[0109] 0.8 < fmt / fmw < 1.8 (10)

[0110] 1.1 < fmt / fmw < 1.7 (10-1)

[0111] When the focal length of the entire system at the wide-angle end is set to fw when focusing on an object at infinity, and the focal length of the lens group with the strongest negative refractive power in the subsequent group is set to fsmax, the zoom lens preferably satisfies the following condition (11). By ensuring that the corresponding value of condition (11) is not below the lower limit, it is beneficial to achieve a high zoom ratio. By ensuring that the corresponding value of condition (11) is not above the upper limit, it is beneficial to suppress aberration changes during zooming, especially astigmatism. By satisfying condition (11), it is beneficial to achieve a high zoom ratio and suppress aberration changes during zooming. In particular, when the lens group with the strongest negative refractive power in the subsequent group is the lens group that moves during zooming, the above effects can be significantly obtained. To obtain even better characteristics, the zoom lens more preferably satisfies the following condition (11-1).

[0112] 1 < fw / |fsmax| < 4 (11)

[0113] 2 < fw / |fsmax| < 3.5 (11-1)

[0114] When the focal length of the entire system at the telephoto end with the object focused at infinity is set to ft, and the focal length of the entire system at the wide-angle end with the object focused at infinity is set to fw, the zoom lens preferably satisfies the following conditional expression (12). By ensuring that the corresponding value of conditional expression (12) is not below the lower limit, it is easy to ensure a zoom ratio suitable for the zoom lens. By ensuring that the corresponding value of conditional expression (12) is not above the upper limit, miniaturization is beneficial. By satisfying conditional expression (12), it is beneficial to construct a small size while ensuring an appropriate zoom ratio. To obtain better characteristics, the zoom lens more preferably satisfies the following conditional expression (12-1).

[0115] 3 < ft / fw < 5 (12)

[0116] 3.9 < ft / fw < 4.2 (12-1)

[0117] When the distance along the optical axis from the lens surface closest to the object to the lens surface closest to the image in the entire system at the wide-angle end is set to Lw, and the focal length of the entire system at the wide-angle end when focusing on an object at infinity is set to fw, the zoom lens preferably satisfies the following condition (13). By ensuring that the corresponding value of condition (13) is not below the lower limit, it is beneficial to suppress image plane curvature. By ensuring that the corresponding value of condition (13) is not above the upper limit, it is beneficial to shorten the overall length, thereby also benefiting weight reduction. By satisfying condition (13), it is beneficial to suppress image plane curvature, miniaturize, and reduce weight. To obtain better characteristics, the zoom lens more preferably satisfies the following condition (13-1).

[0118] 1.3 < Lw / fw < 1.6 (13)

[0119] 1.35 < Lw / fw < 1.55 (13-1)

[0120] When the back focal length of the entire system's air-to-ground distance meter is set to Bfw at the wide-angle end with the object focused at infinity, and the focal length of the entire system's wide-angle end with the object focused at infinity is set to fw, the zoom lens preferably satisfies the following condition (14). By ensuring that the corresponding value of condition (14) is not below the lower limit, the large diameter of the outer diameter of the image-side lens can be suppressed, thus facilitating miniaturization and weight reduction. By ensuring that the corresponding value of condition (14) is not above the upper limit, it is beneficial to correct chromatic aberration and shorten the overall length, thus facilitating weight reduction. By satisfying condition (14), chromatic aberration correction, miniaturization, and weight reduction are beneficial. To obtain even better characteristics, the zoom lens more preferably satisfies the following condition (14-1).

[0121] 0.35 < Bfw / fw < 0.55 (14)

[0122] 0.35 < Bfw / fw < 0.48 (14-1)

[0123] With the radius of curvature of the image-side lens surface of the first lens group set to R1r and the radius of curvature of the object-side lens surface of the second lens group set to R2f, the zoom lens preferably satisfies the following condition (15). By satisfying condition (15), it is beneficial to suppress the variation of spherical aberration during zooming, and thereby easily reduce the burden of aberration correction for other lens groups. To obtain even better characteristics, the zoom lens more preferably satisfies the following condition (15-1).

[0124] 0.8<(R1r+R2f) / (R1r-R2f)<4 (15)

[0125] 1.2<(R1r+R2f) / (R1r-R2f)<2.5 (15-1)

[0126] When the lateral magnification of the anti-vibration unit at the wide-angle end, focused on an object at infinity, is set to βisw, and the combined lateral magnification of all lenses closer to the image side than the anti-vibration unit at the wide-angle end, focused on an object at infinity, is set to βisrw, the zoom lens preferably satisfies the following condition (16). By ensuring that the corresponding value of condition (16) is not below the lower limit, the movement of the anti-vibration unit during image shake correction will not become excessive, thus facilitating miniaturization. By ensuring that the corresponding value of condition (16) is not above the upper limit, the positional accuracy of the anti-vibration unit during image shake correction will not become overly sensitive, thus making it easy to control. By satisfying condition (16), miniaturization of the anti-vibration unit and ensuring appropriate anti-vibration performance are facilitated. To obtain even better characteristics, the zoom lens more preferably satisfies the following condition (16-1).

[0127] 1<|(1-βisw)×βisrw|<5 (16)

[0128] 1.75<|(1-βisw)×βisrw|<3 (16-1)

[0129] In a structure where the intermediate group includes the aforementioned intermediate A group and intermediate B group, and the focusing group includes intermediate B group, when the lateral magnification of intermediate B group at the wide-angle end with the object focused at infinity is set to βmBw, and the combined lateral magnification of all lenses closer to the image side than intermediate B group at the wide-angle end with the object focused at infinity is set to βmBrw, the zoom lens preferably satisfies the following conditional expression (17). By ensuring that the corresponding value of conditional expression (17) does not fall below the lower limit, the amount of movement of the focusing group when focusing towards the closer distance side will not become too large, thus facilitating miniaturization.

[0130] By ensuring that the corresponding value of condition (17) does not exceed the upper limit, the positional accuracy of the focusing group during focusing will not become overly sensitive, thus making it easier to control. Satisfying condition (17) facilitates the miniaturization of the focusing unit and the reduction of the minimum shooting distance. To obtain even better characteristics, zoom lenses are more preferably satisfied with the following condition (17-1).

[0131] 1 < |(1-βmBw 2 )×βmBrw 2 |<10 (17)

[0132] 3<|(1-βmBw 2 )×βmBrw 2 |<5 (17-1)

[0133] When the focal length of the entire system at the wide-angle end, with the focus on an object at infinity, is set to fw, and the focal length of the first lens group is set to f1, the zoom lens preferably satisfies the following condition (18). By ensuring that the corresponding value of condition (18) is not below the lower limit, the large diameter of the beam incident on the second lens group can be suppressed, thus facilitating the miniaturization of the entire system. By ensuring that the corresponding value of condition (18) is not above the upper limit, it is easy to correct various aberrations in the entire system, especially spherical aberration. Satisfying condition (18) facilitates miniaturization and the correction of various aberrations. To obtain even better characteristics, the zoom lens more preferably satisfies the following condition (18-1).

[0134] 0.3 < fw / f1 < 0.8 (18)

[0135] 0.4 < fw / f1 < 0.7 (18-1)

[0136] When the focal length of the entire system at the telephoto end, with the focus on an object at infinity, is set to ft, and the focal length of the first lens group is set to f1, the zoom lens preferably satisfies the following condition (19). By ensuring that the corresponding value of condition (19) is not below the lower limit, the large diameter of the beam incident on the second lens group can be suppressed, thus facilitating the miniaturization of the entire system. By ensuring that the corresponding value of condition (19) is not above the upper limit, it is easy to correct various aberrations in the entire system, especially spherical aberration. Satisfying condition (19) facilitates miniaturization and the correction of various aberrations. To obtain even better characteristics, the zoom lens more preferably satisfies the following condition (19-1).

[0137] 1.7 < ft / f1 < 3 (19)

[0138] 1.8 < ft / f1 < 2.7 (19-1)

[0139] When the focal length of the entire system at the telephoto end, with the focus on an object at infinity, is set to ft, and the focal length of the second lens group is set to f2, the zoom lens preferably satisfies the following condition (20). By ensuring that the corresponding value of condition (20) is not below the lower limit, it is beneficial to achieve a high zoom ratio. By ensuring that the corresponding value of condition (20) is not above the upper limit, it is possible to suppress the large diameter of the beam incident on the intermediate group, thus benefiting the miniaturization of the entire system. Satisfying condition (20) is beneficial for both high zoom ratio and miniaturization. To obtain even better characteristics, the zoom lens more preferably satisfies the following condition (20-1).

[0140] 7 < ft / f2 | < 15 (20)

[0141] 8 < ft / f² | < 14 (20-1)

[0142] When the focal length of the intermediate group at the wide-angle end is set to fmw and the focal length of the second lens group is set to f2, the zoom lens preferably satisfies the following condition (21). By ensuring that the corresponding value of condition (21) is not below the lower limit, the negative refractive power of the second lens group will not become too weak, thus facilitating high zoom ratio. By ensuring that the corresponding value of condition (21) is not above the upper limit, the negative refractive power of the second lens group will not become too strong, thus suppressing the large diameter of the beam incident on the intermediate group and the groups further to the image side than the intermediate group, thereby facilitating miniaturization. Satisfying condition (21) facilitates both high zoom ratio and miniaturization. To obtain even better characteristics, the zoom lens more preferably satisfies the following condition (21-1).

[0143] 0.8 < fmw / |f2| < 1.3 (21)

[0144] 0.85 < fmw / |r2| < 1.1 (21-1)

[0145] When the focal length of the intermediate group at the telephoto end is set to fmt and the focal length of the second lens group is set to f2, the zoom lens preferably satisfies the following condition (22). By ensuring that the corresponding value of condition (22) is not below the lower limit, the negative refractive power of the second lens group will not become too weak, thus facilitating high zoom ratio. By ensuring that the corresponding value of condition (22) is not above the upper limit, the negative refractive power of the second lens group will not become too strong, thus suppressing the large diameter of the beam incident on the intermediate group and the group further to the image side than the intermediate group, thereby facilitating miniaturization. Satisfying condition (22) facilitates both high zoom ratio and miniaturization. To obtain even better characteristics, the zoom lens more preferably satisfies the following condition (22-1).

[0146] 0.9 < fmt / |f2| < 2 (22)

[0147] 1 < fmt / |f2| < 1.8 (22-1)

[0148] When the intermediate group includes at least one positive lens and the dispersion coefficient of the d-line reference of the positive lens of the intermediate group is set to vmp, the intermediate group preferably includes at least one positive lens that satisfies the following condition (23). By ensuring that the corresponding value of condition (23) is not below the lower limit, it is beneficial to correct axial chromatic aberration on the telephoto side. By ensuring that the corresponding value of condition (23) is not above the upper limit, it is possible to prevent the refractive index of the positive lens from becoming too low. Thus, it is easy to ensure refractive power without making the absolute value of the radius of curvature of the lens surface extremely small, and it is possible to prevent the lens from becoming larger in the optical axis direction, which is beneficial to the miniaturization and weight reduction of the intermediate group. By satisfying condition (23), it is beneficial to correct axial chromatic aberration, miniaturize and reduce weight. In order to obtain better characteristics, the intermediate group more preferably includes at least one positive lens that satisfies the following condition (23-1).

[0149] 70 < v mp < 100 (23)

[0150] 80 < v mp < 96 (23-1)

[0151] In a structure where the front group of the second lens group has positive refractive power, when the dispersion coefficient of the d-line reference of the positive lens of the front group of the second lens group is set to v 2p, the front group of the second lens group preferably includes at least one positive lens that satisfies the following condition (24). By ensuring that the corresponding value of condition (24) is not below the lower limit, it is beneficial to correct axial chromatic aberration on the telephoto side. By ensuring that the corresponding value of condition (24) is not above the upper limit, it is possible to prevent the refractive index of the positive lens from becoming too low. Thus, it is easy to ensure refractive power without making the absolute value of the radius of curvature of the lens surface extremely small, and it is possible to prevent the lens from becoming larger in the optical axis direction, which is beneficial to the miniaturization and weight reduction of the front group of the second lens group. By satisfying condition (24), it is beneficial to correct axial chromatic aberration, miniaturize, and reduce weight. To obtain better characteristics, the front group of the second lens group more preferably includes at least one positive lens that satisfies the following condition (24-1).

[0152] 50 < v 2p < 90 (24)

[0153] 65 < v 2p < 85 (24-1)

[0154] When the radius of curvature of the lens surface closest to the object in the first lens group is set to R1f, and the radius of curvature of the lens surface closest to the image in the first lens group is set to R1r, the zoom lens preferably satisfies the following condition (25). By satisfying condition (25), it is beneficial to correct spherical aberration, and thereby it is easier to reduce the burden of aberration correction for other lens groups. To obtain better characteristics, the zoom lens more preferably satisfies the following condition (25-1).

[0155] -6<(R1f+R1r) / (R1f-R1r)<-1 (25)

[0156] -5<(R1f+R1r) / (R1f-R1r)<-2 (25-1)

[0157] When the average value of the dispersion coefficient of the d-line reference of all positive lenses in the first lens group is set to vave1p, the zoom lens preferably satisfies the following condition (26). By ensuring that the corresponding value of condition (26) is not below the lower limit, it is beneficial to correct axial chromatic aberration on the telephoto side. By ensuring that the corresponding value of condition (26) is not above the upper limit, it is possible to prevent the refractive index of the positive lens from becoming too low. As a result, it is easy to ensure refractive power without making the absolute value of the radius of curvature of the lens surface extremely small, and it is possible to prevent the lens from becoming larger in the optical axis direction, thus facilitating the miniaturization and weight reduction of the first lens group. By satisfying condition (26), it is beneficial to correct axial chromatic aberration, miniaturize, and reduce weight. To obtain better characteristics, the zoom lens more preferably satisfies the following condition (26-1).

[0158] 65 < v ave1p < 85 (26)

[0159] 70 < v ave1p < 80 (26-1)

[0160] When the average value of the dispersion coefficient of the d-line reference of all negative lenses in the second lens group is set to vave2n, the zoom lens preferably satisfies the following condition (27). By ensuring that the corresponding value of condition (27) is not below the lower limit, it is beneficial to correct chromatic aberration. By ensuring that the corresponding value of condition (27) is not above the upper limit, it is possible to prevent the refractive index of the negative lens from becoming too low. As a result, it is easy to ensure refractive power without making the absolute value of the radius of curvature of the lens surface extremely small, and it is possible to prevent the increase in lens volume, thus facilitating the weight reduction of the vibration stabilization unit. By satisfying condition (27), it is beneficial to correct chromatic aberration and reduce weight. To obtain better characteristics, the zoom lens more preferably satisfies the following condition (27-1).

[0161] 30 < v ave2n < 60 (27)

[0162] 35<v ave2n<52 (27-1)

[0163] In a structure where the intermediate group includes the aforementioned intermediate A group and intermediate B group, when the average value of the dispersion coefficients of the d-line reference of all positive lenses in the intermediate A group is set as vavemAp, the zoom lens preferably satisfies the following conditional expression (28). By ensuring that the corresponding value of conditional expression (28) is not below the lower limit, it is beneficial to correct axial chromatic aberration on the telephoto side. By ensuring that the corresponding value of conditional expression (28) is not above the upper limit, it is possible to prevent the refractive index of the positive lenses from becoming too low. As a result, it is easy to ensure refractive power without making the absolute value of the radius of curvature of the lens surface extremely small, and it is possible to prevent the lens from becoming larger in the optical axis direction, thus facilitating the miniaturization and weight reduction of the intermediate group. By satisfying conditional expression (28), it is beneficial to correct axial chromatic aberration, miniaturize, and reduce weight. To obtain better characteristics, the zoom lens more preferably satisfies the following conditional expression (28-1).

[0164] 60 < v avemAp < 85 (28)

[0165] 67 < v avemAp < 80 (28-1)

[0166] When the vibration damping assembly includes at least one positive lens and the dispersion coefficient of the d-line reference of the positive lens of the vibration damping assembly is set to visp, the vibration damping assembly preferably includes at least one positive lens that satisfies the following condition (29). By satisfying condition (29), it is beneficial to suppress the variation of magnification chromatic aberration during image jitter correction. To obtain better characteristics, the vibration damping assembly more preferably includes at least one positive lens that satisfies the following condition (29-1).

[0167] 15 < v isp < 40 (29)

[0168] 20 < v isp < 33 (29-1)

[0169] When the focal length of the entire system at the wide-angle end, with the focus on an object at infinity, is set to fw, and the focal length of the second lens group is set to f2, the zoom lens preferably satisfies the following condition (30). By ensuring that the corresponding value of condition (30) is not below the lower limit, the negative refractive power of the second lens group will not become too weak, thus facilitating high zoom ratio. By ensuring that the corresponding value of condition (30) is not above the upper limit, the negative refractive power of the second lens group will not become too strong, thus suppressing the large diameter of the beam incident on the intermediate group and the groups further to the image side than the intermediate group, thereby facilitating miniaturization. Satisfying condition (30) facilitates both high zoom ratio and miniaturization. To obtain even better characteristics, the zoom lens more preferably satisfies the following condition (30-1).

[0170] 1 < fw / |f2| < 5 (30)

[0171] 2 < fw / |f2| < 3.5 (30-1)

[0172] Specifically, each group can adopt the following structure, for example.

[0173] The first lens group can be configured to include one negative lens and two positive lenses. In this case, it is advantageous for correcting axial chromatic aberration, and it is also advantageous for weight reduction compared to cases where the first lens group includes four or more lenses.

[0174] For example, the first lens group can be configured to include, from the object side to the image side, a combined lens consisting of a negative lens and a positive lens, and a positive lens. More specifically, the first lens group can be configured to include, from the object side to the image side, a negative meniscus lens with its convex surface facing the object side, a biconvex lens, and a positive meniscus lens with its convex surface facing the object side.

[0175] Preferably, the number of lenses constituting the front group of the second lens group is three or fewer. In this case, it is beneficial to the miniaturization and weight reduction of the entire system.

[0176] The front group of the second lens group can be configured to include only one positive lens, or it can be configured to include a combined lens consisting of a positive lens and a negative lens.

[0177] The preferred anti-vibration assembly includes two negative lenses and one positive lens. In this case, it is beneficial to suppress the performance degradation caused by chromatic aberration changes during image jitter correction. Furthermore, when the anti-vibration assembly includes two negative lenses and one positive lens, it is easier to correct chromatic aberration compared to when the anti-vibration assembly includes two or fewer lenses, and compared to when the anti-vibration assembly includes four or more lenses, it is beneficial for miniaturization and weight reduction of the anti-vibration unit.

[0178] The preferred vibration damping assembly comprises a combined lens consisting of a negative lens and a positive lens sequentially joined from the object side, or a combined lens consisting of a positive lens and a negative lens sequentially joined from the object side. In this case, it is advantageous to reduce the degradation of optical performance caused by assembly errors.

[0179] For example, the vibration damping assembly can be configured such that, from the object side toward the image side, it sequentially includes a combined lens consisting of a negative lens and a positive lens, and a negative lens. More specifically, the vibration damping assembly can be configured such that, from the object side toward the image side, it sequentially includes a combined lens consisting of a negative lens with its concave surface facing the image side and a positive meniscus lens with its convex surface facing the object side, and a negative lens with its concave surface facing the object side.

[0180] Preferably, an aperture diaphragm is positioned between the second lens group and the intermediate lens group. In this case, the vibration damping group and the aperture diaphragm are close to each other, which facilitates the miniaturization of the vibration damping group.

[0181] Preferably, the intermediate group includes two or fewer lens groups. In this case, it is beneficial for miniaturization and weight reduction. For example, the intermediate group A can be configured to include one lens group, and the intermediate group B can be configured to include one lens group.

[0182] The subsequent group can be configured to include two lens groups whose spacing changes during zooming. For example, the subsequent group can be configured to include, from the object side toward the image side, a lens group with negative refractive power and a lens group with positive refractive power, with the spacing between the lens group with negative refractive power and the lens group with positive refractive power changing during zooming. In this case, the lens group with negative refractive power can be used to tilt the light rays away from the optical axis Z, and the lens group with positive refractive power can be used to reduce the angle between the light rays and the optical axis Z. Therefore, it is beneficial to ensure a large image circle while reducing the incident angle of the principal ray of the off-axis beam incident on the image plane.

[0183] The preferred lens group, which has the largest absolute value of refractive power within the subsequent lens group, includes at least one positive lens and at least one negative lens. In this case, it is beneficial to correct astigmatism and chromatic aberration, and to suppress aberration variations during zooming.

[0184] A zoom lens can be configured such that all lens groups move during zooming, or it can be configured to include a lens group that is fixed relative to the image plane during zooming. For example, the subsequent lens group can be configured to include a lens group that is fixed relative to the image plane during zooming on the image-side closest to the zoom. In this case, by using the lens group that is fixed relative to the image plane on the image-side closest to the zoom, it is possible to suppress the variation of chromatic aberration during zooming. Furthermore, it can be configured such that the second lens group is fixed relative to the image plane during zooming. In this case, it is beneficial to reduce the degradation of optical performance caused by errors, and the device can be further simplified, thus facilitating the miniaturization and weight reduction of the device.

[0185] Including structures related to conditional expressions, the above-mentioned preferred structures and implementable structures can be combined arbitrarily, and preferably selected appropriately according to the required specifications.

[0186] As an example, a preferred embodiment of the zoom lens of the present invention is a zoom lens comprising, from the object side toward the image side, a first lens group having positive refractive power, a second lens group having negative refractive power arranged continuously with the first lens group, an intermediate group having positive refractive power including at least one lens group, and a subsequent group having negative refractive power including at least one lens group. During zooming, the first lens group moves along the optical axis, the interval between the first lens group and the second lens group changes, the interval between the second lens group and the intermediate group changes, and the interval between the intermediate group and the subsequent group changes. The second lens group, from the object side toward the image side, comprises, in sequence, a front group of the second lens group fixed for image shake correction and an anti-vibration group having negative refractive power that moves along a direction intersecting the optical axis for image shake correction. This zoom lens satisfies the above-mentioned conditional expressions (1) and (2). The zoom lens according to this preferred embodiment has anti-vibration performance, is beneficial for miniaturization and weight reduction, and easily maintains good optical performance.

[0187] Next, embodiments of the zoom lens of the present invention will be described with reference to the accompanying drawings.

[0188] [Example 1]

[0189] Figure 1 The diagram shows a cross-sectional view of the structure of the zoom lens at the wide-angle end according to Embodiment 1 of the present invention. Figure 2 The diagram shows the structure and cross-sectional view of the beam at various zoom levels of the zoom lens. Figure 1 and Figure 2 The image shows the state of focusing on an object at infinity; the left side is the object side, and the right side is the image side. Figure 2 In the diagram, the upper section labeled "WIDE" indicates the wide-angle end, the middle section labeled "MIDDLE" indicates the intermediate focal length end, and the lower section labeled "TELE" indicates the telephoto end. Figure 2 In the diagram, the on-axis beam wa at the wide-angle end and the beam wb at the maximum angle of view are shown; the on-axis beam ma at the intermediate focal length and the beam mb at the maximum angle of view are shown; and the on-axis beam ta at the telephoto end and the beam tb at the maximum angle of view are shown. As an example, Figure 2 The table shows Lw, DL1, and Llist used in the above conditional expressions.

[0190] The zoom lens of Embodiment 1, along the optical axis Z from the object side to the image side, includes, in sequence, a first lens group G1, a second lens group G2, an aperture, a third lens group G3, a fourth lens group G4, a fifth lens group G5, and a sixth lens group G6. In this zoom lens, when zooming from the wide-angle end to the telephoto end, the five lens groups (G1 through G5) change the spacing of adjacent lens groups along the optical axis Z, while the sixth lens group G6 is fixed relative to the image plane Sim. The aperture St moves integrally with the third lens group G3. Figure 1 Below each lens group, a single arrow indicates the approximate direction of movement of the lens group during zooming from the wide-angle end to the telephoto end, and a grounding mark is shown for the lens group that is fixed during zooming. In the zoom lens of Embodiment 1, the intermediate group includes the third lens group G3 and the fourth lens group G4, and the subsequent groups include the fifth lens group G5 and the sixth lens group G6.

[0191] Lens group G1 consists of three lenses, L11 to L13, arranged sequentially from the object side to the image side. Lens group G2 consists of four lenses, L21 to L24, arranged sequentially from the object side to the image side. Lens group G3 consists of three lenses, L31 to L33, arranged sequentially from the object side to the image side. Lens group G4 consists of three lenses, L41 to L43, arranged sequentially from the object side to the image side. Lens group G5 consists of two lenses, L51 and L52, arranged sequentially from the object side to the image side. Lens group G6 includes lens L61. The vibration damping group consists of three lenses, L22 to L24. The focusing group includes lens group G4. Figure 1 In the diagram, a double arrow pointing vertically is marked below the vibration damping group, and a double arrow pointing horizontally is marked below the focusing group.

[0192] In addition, Figure 1 and Figure 2 The image illustrates an example where a parallel flat optical component PP is positioned between the zoom lens and the image plane (Sim) assuming a zoom lens is used in a camera device. The optical component PP is assumed to be a component such as various filters and / or cover glass. These filters include, for example, low-pass filters, infrared cutoff filters, and filters that cut off specific wavelength regions. The optical component PP may be a component without refractive power, or it may be a structure in which the optical component PP is omitted.

[0193] Regarding the zoom lens of Example 1, basic lens data is shown in Table 1, specifications and variable surface spacing are shown in Table 2, and aspherical coefficients are shown in Table 3. In Table 1, the Sn column shows the surface number when the surface closest to the object side is set as surface 1 and the numbering increases sequentially towards the image side; the R column shows the radius of curvature of each surface; the D column shows the surface spacing of each surface and its image-side adjacent surface on the optical axis; the Nd column shows the refractive index of each component relative to the d-line; and the vd column shows the dispersion coefficient of each component based on the d-line reference.

[0194] In Table 1, the radius of curvature of the convex surface facing the object side is marked positive, and the radius of curvature of the convex surface facing the image side is marked negative. Table 1 also shows the aperture St and optical components PP. The term (St) is recorded along with the surface number in the surface number column corresponding to the aperture St. The value in the bottom column of D in Table 1 is the interval between the surface closest to the image side and the image plane Sim. In Table 1, the variable surface interval for zooming is indicated by the notation DD[], with the object-side surface number of the interval marked in [] and recorded in column D.

[0195] Table 2 shows the zoom ratio Zr, focal length f, open F-number FNo., maximum full angle of view 2ω, and variable plane spacing during zoom. The (°) in the 2ω column indicates the unit as degrees. In Table 2, the values ​​for the wide-angle, intermediate focal length, and telephoto ends are shown in the columns described as WIDE, MIDDLE, and TELE, respectively. The values ​​shown in Tables 1 and 2 are based on the d-line when focusing on an object at infinity.

[0196] In Table 1, the surface numbers of aspherical surfaces are marked with an asterisk (*), and the paraxial radius of curvature is recorded in the radius of curvature column. In Table 3, the surface number of the aspherical surface is shown in the Sn column, and the aspherical coefficients for each aspherical surface are shown in the KA and Am (m = 3, 4, 5, ... 10) columns.

[0197] The numerical values ​​of the aspheric coefficients in Table 3, “E±n” (n: an integer), represent “×10”. ±n KA and Am are the aspheric coefficients in the aspheric formula expressed by the following equation.

[0198] Zd=C×h 2 / {1+(1-KA×C 2 × h 2) 1 / 2}+∑Am×h m

[0199] in,

[0200] Zd: Aspherical depth (the length of the perpendicular line from a point on the aspherical surface at height h to a plane tangent to the vertex of the aspherical surface and perpendicular to the optical axis);

[0201] h: Height (distance from the optical axis to the lens surface);

[0202] C: The reciprocal of the paraxial radius of curvature;

[0203] KA, Am: Aspheric coefficients

[0204] In aspherical form, ∑ represents the summation related to m.

[0205] In the data in each table, degrees are used as the unit for angles and millimeters as the unit for lengths. Optical systems can be used at both magnified and reduced scales, so other appropriate units may also be used. Furthermore, the values ​​are rounded to a specified number of decimal places in the tables shown below.

[0206] [Table 1]

[0207] Example 1

[0208] Sn R D Nd vd 1 206.29219 2.000 1.91082 35.25 2 92.61100 6.290 1.48749 70.42 3 -348.39649 0.100 4 72.85426 5.250 1.49700 81.59 5 401.19231 DD[5] 6 61.75210 3.470 1.48749 70.39 7 ∞ 14.951 8 ∞ 1.010 1.78590 44.17 9 15.63300 3.160 1.92286 20.89 10 26.73519 2.931 11 -31.18271 1.000 1.91082 35.25 12 -221.14090 DD

[12] 13 (St) ∞ 1.000 *14 20.38050 4.150 1.58313 59.38 *15 211.70314 8.090 16 199.40281 1.000 1.83481 42.73 17 16.50800 5.480 1.49700 81.61 18 -32.80289 DD

[18] 19 32.74333 2.580 1.83481 42.73 20 ∞ 1.567 21 -23.09227 1.430 1.78470 26.27 22 71.40700 3.750 1.73800 32.33 23 -23.27688 DD

[23] 24 -92.91465 2.380 1.92119 23.96 25 -26.32000 1.010 1.78800 47.52 26 26.32000 DD

[26] 27 -109.91337 3.190 1.58144 40.75 28 -38.02918 26.310 29 ∞ 2.850 1.54763 54.98 30 ∞ 1.139

[0209] [Table 2] Example 1

[0210] WIDE MIDDLE TELE Zr 1.0 2.0 4.0 f 72.118 144.236 291.358 FNo. 4.11 4.62 5.76 2ω(°) 21.8 11.0 5.6 DD[5] 0.999 38.238 57.009 DD

[12] 13.319 6.720 2.224 DD

[18] 3.875 13.038 16.268 DD

[23] 12.940 10.585 3.046 DD

[26] 2.835 8.681 37.443

[0211] [Table 3]

[0212] Example 1

[0213] Sn 14 15 KA 1.0000000E+00 1.0000000E+00 A3 0.0000000E+00 0.0000000E+00 A4 -5.7977453E-06 7.0429674E-06 A5 1.9069508E-07 -1.6063152E-07 A6 -1.3138935E-07 -6.4035922E-09 A7 3.3398108E-08 1.7295082E-08 A8 -3.2768000E-09 -2.4892221E-09 A9 7.9633108E-11 9.8110299E-11 A10 5.2428800E-12 3.7353005E-12

[0214] Figure 3 The diagram shows the aberrations of the zoom lens of Embodiment 1 when focused on an object at infinity. Figure 3 In the image, from left to right, spherical aberration, astigmatism, distortion aberration, and magnification chromatic aberration are shown. Figure 3 In the diagram, the upper section marked "WIDE" shows aberrations at the wide-angle end, the middle section marked "MIDDLE" shows aberrations at the intermediate focal length, and the lower section marked "TELE" shows aberrations at the telephoto end. In the spherical aberration diagram, aberrations below the d-line, C-line, F-line, and g-line are shown with solid lines, long dashed lines, short dashed lines, and single-dot dashed lines, respectively. In the astigmatism diagram, aberrations below the d-line in the sagittal direction are shown with solid lines, and aberrations below the d-line in the meridional direction are shown with short dashed lines. In the distortion aberration diagram, aberrations below the d-line are shown with solid lines. In the magnification chromatic aberration diagram, aberrations below the C-line, F-line, and g-line are shown with long dashed lines, short dashed lines, and single-dot dashed lines, respectively. FNo. in the spherical aberration diagram represents the F-value, and ω in other aberration diagrams represents the half-angle. Figure 3 The values ​​of FNo. and ω corresponding to the upper end of the vertical axis of each graph are shown in the figure.

[0215] Unless otherwise specified, the notation, meaning, recording method and illustration method of the data related to Embodiment 1 above are the same in the following embodiments, so repeated descriptions are omitted below.

[0216] [Example 2]

[0217] Figure 4The image shows a cross-sectional view of the zoom lens of Embodiment 2 at its wide-angle end, with the lens focused on an object at infinity. The zoom lens of Embodiment 2 comprises, along the optical axis Z from the object side towards the image side, a first lens group G1, a second lens group G2, an aperture, a third lens group G3, a fourth lens group G4, a fifth lens group G5, and a sixth lens group G6. In this zoom lens, when zooming from the wide-angle end to the telephoto end, the five lens groups (G1 through G5) change the spacing between adjacent lens groups along the optical axis Z, while the sixth lens group G6 is fixed relative to the image plane Sim. The aperture St moves integrally with the third lens group G3. In the zoom lens of Embodiment 2, the intermediate groups include the third lens group G3 and the fourth lens group G4, and the subsequent groups include the fifth lens group G5 and the sixth lens group G6.

[0218] Lens group G1 consists of three lenses, L11 to L13, arranged sequentially from the object side to the image side. Lens group G2 consists of four lenses, L21 to L24, arranged sequentially from the object side to the image side. Lens group G3 consists of three lenses, L31 to L33, arranged sequentially from the object side to the image side. Lens group G4 consists of three lenses, L41 to L43, arranged sequentially from the object side to the image side. Lens group G5 consists of three lenses, L51 to L53, arranged sequentially from the object side to the image side. Lens group G6 includes lens L61. The vibration damping group consists of three lenses, L22 to L24. The focusing group includes lens group G4.

[0219] Regarding the zoom lens of Example 2, the basic lens data is shown in Table 4, the specifications and variable surface spacing are shown in Table 5, the aspherical coefficients are shown in Table 6, and the various aberrations are illustrated in Table 7. Figure 5 .

[0220] [Table 4]

[0221] Example 2

[0222] Sn R D Nd vd 1 250.87223 2.000 1.80610 33.27 2 105.30174 5.927 1.48749 70.42 3 -303.52760 0.100 4 87.46594 4.389 1.49700 81.59 5 399.65657 DD[5] 6 140.62589 2.785 1.48749 70.42 7 -140.62589 8.374 8 ∞ 1.010 1.83481 42.74 9 18.33540 3.050 1.89286 20.36 10 36.43153 2.712 11 -31.28675 1.000 1.91082 35.25 12 -79.39477 DD

[12] 13 (St) ∞ 0.750 *14 19.98987 4.043 1.58313 59.38 *15 97.37526 6.858 16 35.73001 1.000 1.88300 39.22 17 13.94110 5.223 1.49700 81.59 18 -241.76478 DD

[18] 19 132.45690 2.361 1.78800 47.37 20 -50.27079 0.860 21 -23.33672 1.010 1.63980 34.47 22 23.33672 3.750 1.87070 40.73 23 -43.37114 DD

[23] 24 76.20188 1.000 1.74100 52.64 25 17.84587 1.707 26 -965.00477 3.782 1.64769 33.79 27 -13.93074 1.000 1.78800 47.37 28 ∞ DD

[28] 29 -47.33994 2.692 1.91082 35.25 30 -29.43105 26.295 31 ∞ 2.850 1.54763 54.98 32 ∞ 1.118

[0223] [Table 5]

[0224] Example 2

[0225] WIDE MIDDLE TELE Zr 1.0 2.0 4.0 f 72.075 144.150 291.184 FNo. 4.12 5.20 5.77 2ω(°) 21.6 11.0 5.6 DD[5] 1.285 43.002 81.265 DD

[12] 14.647 6.105 1.786 DD

[18] 6.015 8.482 16.446 DD

[23] 12.943 12.086 2.270 DD

[28] 2.520 13.722 22.611

[0226] [Table 6]

[0227] Example 2

[0228] Sn 14 15 KA 1.0000000E+00 1.0000000E+00 A3 0.0000000E+00 0.0000000E+00 A4 -1.9928253E-06 8.5881366E-06 A5 -8.7170296E-07 -1.1041250E-06 A6 2.3035450E-07 2.8920056E-07 A7 -3.4175125E-08 -4.3448393E-08 A8 2.1044007E-09 3.2281461E-09 A9 4.0533371E-12 -8.4229097E-11 A10 -5.2428824E-12 -2.4193979E-12

[0229] [Example 3]

[0230] Figure 6The image shows a cross-sectional view of the zoom lens of Embodiment 3 at its wide-angle end, with the lens focused on an object at infinity. The zoom lens of Embodiment 3 comprises, along the optical axis Z from the object side to the image side, a first lens group G1, a second lens group G2, an aperture, a third lens group G3, a fourth lens group G4, a fifth lens group G5, and a sixth lens group G6. In this zoom lens, when zooming from the wide-angle end to the telephoto end, the five lens groups (G1 through G5) change the spacing between adjacent lens groups along the optical axis Z, while the sixth lens group G6 is fixed relative to the image plane Sim. The aperture St moves integrally with the third lens group G3. In the zoom lens of Embodiment 3, the intermediate groups include the third lens group G3 and the fourth lens group G4, and the subsequent groups include the fifth lens group G5 and the sixth lens group G6.

[0231] Lens group G1 consists of three lenses, L11 to L13, arranged sequentially from the object side to the image side. Lens group G2 consists of five lenses, L21 to L25, arranged sequentially from the object side to the image side. Lens group G3 consists of three lenses, L31 to L33, arranged sequentially from the object side to the image side. Lens group G4 consists of two lenses, L41 and L42, arranged sequentially from the object side to the image side. Lens group G5 consists of two lenses, L51 and L52, arranged sequentially from the object side to the image side. Lens group G6 includes lens L61. The vibration damping group consists of three lenses, L23 to L25. The focusing group includes lens group G4.

[0232] Regarding the zoom lens of Example 3, the basic lens data is shown in Table 7, the specifications and variable surface spacing are shown in Table 8, the aspherical coefficients are shown in Table 9, and the various aberrations are illustrated in Table 1. Figure 7 .

[0233] [Table 7]

[0234] Example 3

[0235] Sn R D Nd vd 1 166.59780 2.000 1.91082 35.25 2 85.11296 6.850 1.53775 74.70 3 -271.98598 0.100 4 67.22483 5.750 1.49700 81.61 5 400.05909 DD[5] 6 46.40002 5.107 1.60300 65.44 7 -86.03107 1.000 1.49700 81.61 8 38.26149 11.857 9 -299.75994 1.010 1.95375 32.32 10 20.93172 2.377 1.98613 16.48 11 44.07436 2.111 12 -32.26585 1.000 1.88300 40.76 13 ∞ DD

[13] 14 (St) ∞ 1.500 *15 40.46496 2.953 1.58313 59.38 *16 -70.97676 0.100 17 30.36208 10.625 1.43875 94.66 18 -21.21602 0.100 19 107.96053 1.000 1.90366 31.31 20 20.95730 DD

[20] 21 30.43167 4.071 1.84666 23.78 22 -29.10715 2.662 1.98613 16.48 23 -259.11585 DD

[23] 24 -87.72723 3.097 1.90366 31.31 25 -18.87620 1.010 1.77250 49.60 26 21.79820 DD

[26] 27 2032.60979 4.128 1.48749 70.44 28 -41.52570 29.892 29 ∞ 2.850 1.54763 54.98 30 ∞ 1.195

[0236] [Table 8]

[0237] Example 3

[0238] WIDE MIDDLE TELE Zr 1.0 2.0 4.0 f 72.145 144.291 291.467 FNo. 4.13 4.18 5.70 2ω(°) 21.8 10.8 5.6 DD[5] 4.306 33.546 42.787 DD

[13] 14.582 8.711 1.296 DD

[20] 2.699 17.130 24.557 DD

[23] 8.801 6.364 2.748 DD

[26] 5.349 3.024 29.594

[0239] [Table 9]

[0240] Example 3

[0241] Sn 14 15 KA 1.0000000E+00 1.0000000E+00 A3 0.0000000E+00 0.0000000E+00 A4 -7.4717611E-06 2.3402113E-05 A5 -5.7058727E-07 6.4328155E-07 A6 1.2997755E-07 -3.6792554E-08 A7 -1.2190563E-08 -6.4637261E-09 A8 -7.1328468E-10 2.3685359E-09 A9 3.7301651E-10 2.1692872E-11 A10 -2.7539149E11 -1.4225501E-11

[0242] [Example 4]

[0243] Figure 8The image shows a cross-sectional view of the zoom lens of Embodiment 4 at its wide-angle end, with the lens focused on an object at infinity. The zoom lens of Embodiment 4 comprises, along the optical axis Z from the object side towards the image side, a first lens group G1, a second lens group G2, an aperture, a third lens group G3, a fourth lens group G4, a fifth lens group G5, and a sixth lens group G6. In this zoom lens, when zooming from the wide-angle end to the telephoto end, the four lens groups G1, G3, G4, and G5 change their spacing relative to adjacent lens groups along the optical axis Z and move accordingly. The second lens group G2 and the sixth lens group G6 are fixed relative to the image plane Sim, and the aperture St moves integrally with the third lens group G3. In the zoom lens of Embodiment 4, the intermediate group includes the third lens group G3 and the fourth lens group G4, and the subsequent groups include the fifth lens group G5 and the sixth lens group G6.

[0244] Lens group G1 consists of three lenses, L11 to L13, arranged sequentially from the object side to the image side. Lens group G2 consists of four lenses, L21 to L24, arranged sequentially from the object side to the image side. Lens group G3 consists of three lenses, L31 to L33, arranged sequentially from the object side to the image side. Lens group G4 consists of three lenses, L41 to L43, arranged sequentially from the object side to the image side. Lens group G5 consists of three lenses, L51 to L53, arranged sequentially from the object side to the image side. Lens group G6 includes lens L61. The vibration damping group consists of three lenses, L22 to L24. The focusing group includes lens group G4.

[0245] Regarding the zoom lens of Example 4, the basic lens data is shown in Table 10, the specifications and variable surface spacing are shown in Table 11, the aspherical coefficients are shown in Table 12, and the various aberrations are illustrated in Table 13. Figure 9 .

[0246] [Table 10]

[0247] Example 4

[0248] Sn R D Nd vd 1 254.07527 2.000 1.80610 33.27 2 100.16956 6.274 1.48749 70.42 3 -270.04988 0.100 4 83.92452 4.568 1.49700 81.59 5 394.41685 DD[5] 6 183.49891 2.446 1.48749 70.42 7 -183.53469 13.227 8 ∞ 1.011 1.83481 42.74 9 17.99368 3.250 1.89286 20.36 10 37.83196 2.965 11 -31.07695 1.000 1.95375 32.32 12 -72.72799 DD

[12] 13 (St) ∞ 0.750 *14 20.19515 3.890 1.58313 59.38 *15 80.22129 7.855 16 36.93867 1.000 1.88300 39.22 17 14.36717 5.074 1.49700 81.59 18 -250.69470 DD

[18] 19 134.07652 2.386 1.78800 47.37 20 -49.43463 0.857 21 -23.56084 1.135 1.63980 34.47 22 23.56084 3.750 1.87070 40.73 23 -45.52795 DD

[23] 24 58.98198 1.000 1.74100 52.64 25 18.33857 1.453 26 144.88405 3.857 1.64769 33.79 27 -14.74163 1.000 1.78800 47.37 28 175.58333 DD

[28] 29 -33.66681 2.601 1.80610 33.27 30 -24.66375 26.221 31 ∞ 2.850 1.54763 54.98 32 ∞ 1.127

[0249] [Table 11]

[0250] Example 4

[0251] WIDE MIDDLE TELE Zr 1.0 2.0 4.0 f 72.087 144.174 291.231 FNo. 4.12 4.65 5.77 2ω(°) 21.6 11.0 5.6 DD[5] 1.018 41.596 72.481 DD

[12] 18.532 9.309 1.726 DD

[18] 7.648 10.071 18.476 DD

[23] 12.847 11.439 2.292 DD

[28] 3.361 11.545 19.862

[0252] [Table 12]

[0253] Example 4

[0254] Sn 14 15 KA 1.0000000E+00 1.0000000E+00 A3 0.0000000E+00 0.0000000E+00 A4 -1.6693880E-06 7.7614047E-06 A5 -8.3412472E-07 -9.5064558E-07 A6 2.1943876E-07 2.4003477E-07 A7 -3.3899930E-08 -3.7251968E-08 A8 2.4176128E-09 3.2647523E-09 A9 -2.4787767E-11 -1.2773873E-10 A10 -5.2428815E-12 -1.3309567E-12

[0255] [Example 5]

[0256] Figure 10 The image shows a cross-sectional view of the zoom lens of Embodiment 5 at its wide-angle end, with the lens focused on an object at infinity. The zoom lens of Embodiment 5 comprises, along the optical axis Z from the object side to the image side, a first lens group G1, a second lens group G2, an aperture, a third lens group G3, a fourth lens group G4, a fifth lens group G5, and a sixth lens group G6. In this zoom lens, when zooming from the wide-angle end to the telephoto end, the five lens groups (G1 through G5) change the spacing between adjacent lens groups along the optical axis Z, while the sixth lens group G6 is fixed relative to the image plane Sim. The aperture St moves integrally with the third lens group G3. In the zoom lens of Embodiment 5, the intermediate groups include the third lens group G3 and the fourth lens group G4, and the subsequent groups include the fifth lens group G5 and the sixth lens group G6.

[0257] Lens group G1 consists of three lenses, L11 to L13, arranged sequentially from the object side to the image side. Lens group G2 consists of four lenses, L21 to L24, arranged sequentially from the object side to the image side. Lens group G3 consists of three lenses, L31 to L33, arranged sequentially from the object side to the image side. Lens group G4 consists of three lenses, L41 to L43, arranged sequentially from the object side to the image side. Lens group G5 consists of two lenses, L51 and L52, arranged sequentially from the object side to the image side. Lens group G6 includes lens L61. The vibration damping group consists of three lenses, L22 to L24. The focusing group includes lens group G4.

[0258] Regarding the zoom lens of Example 5, the basic lens data is shown in Table 13, the specifications and variable surface spacing are shown in Table 14, the aspherical coefficients are shown in Table 15, and the various aberrations are illustrated in Table 16. Figure 11 .

[0259] [Table 13]

[0260] Example 5

[0261] Sn R D Nd vd 1 223.19562 2.000 1.91082 35.25 2 95.18429 6.182 1.48749 70.44 3 -303.16549 0.100 4 73.55061 5.500 1.49700 81.61 5 400.05795 DD[5] 6 66.40803 3.081 1.48749 70.44 7 ∞ 16.774 8 -173.87769 1.010 1.75500 52.32 9 15.62491 3.250 1.92119 23.96 10 28.62313 2.723 11 -37.40437 1.000 1.91082 35.25 12 ∞ DD

[12] 13 (St) ∞ 1.500 *14 24.39651 3.731 1.58313 59.46 *15 640.03276 8.352 16 413.72968 1.000 1.83481 42.74 17 20.55215 5.098 1.49700 81.61 18 -28.05035 DD

[18] 19 33.84068 2.449 1.78800 47.37 20 ∞ 1.025 21 -35.21923 2.750 1.75575 24.71 22 125.00563 4.510 1.72047 34.71 23 -34.31286 DD

[23] 24 -139.08043 1.842 1.92119 23.96 25 -29.72012 1.010 1.78800 47.37 26 24.18590 DD

[26] 27 -55.68093 2.419 1.66382 27.35 28 -34.02470 29.353 29 ∞ 2.850 1.54763 54.98 30 ∞ 1.146

[0262] [Table 14]

[0263] Example 5

[0264] WIDE MIDDLE TELE Zr 1.0 2.0 4.0 f 72.102 144.205 291.294 FNo. 4.12 4.66 5.77 2ω(°) 22.0 11.0 5.6 DD[5] 1.000 37.755 56.634 DD

[12] 13.628 7.078 2.453 DD

[18] 3.198 15.274 18.788 DD

[23] 11.464 9.194 1.993 DD

[26] 3.467 7.657 34.630

[0265] [Table 15]

[0266] Example 5

[0267] Sn 14 15 KA 1.0000000E+00 1.0000000E+00 A3 0.0000000E+00 0.0000000E+00 A4 -1.8476524E-06 1.0156779E-05 A5 5.0693734E-07 4.6058114E-07 A6 -1.2840468E-07 -1.0184763E-07 A7 1.3047210E-08 6.1814506E-09 A8 -4.1064596E-10 6.1484724E-10 A9 -2.5544624E-11 -1.0649134E-10 A10 1.3165304E-12 3.7829322E-12

[0268] Table 16 shows the corresponding values ​​of the conditional expressions (1) to (30) for the zoom lenses of Examples 1 to 5.

[0269] [Table 16]

[0270] Formula number Mode Example 1 Example 2 Example 3 Example 4 Example 5 (1) DL1 / Lw 0.75 0.83 0.61 0.61 0.74 (2) |(1-βist)×βisrt| 5.05 3.92 5.19 3.77 4.99 (3) fmA / fmB 0.95 1.02 0.96 1.07 0.90 (4) DmAB / fmB 0.38 0.39 0.66 0.43 0.42 (5) <![CDATA[|(1-βmBt 2 )×βmBrt 2 |]]> 6.56 5.70 6.71 5.10 6.63 (6) Llist / f1 0.610 0.655 0.585 0.655 0.613 (7) fw / |fis| 3.73 2.84 3.82 2.77 3.71 (8) fw / fmw 2.53 2.44 3.16 2.27 2.62 (9) ft / fmt 8.14 8.16 7.98 7.59 8.06 (10) fmt / fmw 1.25 1.21 1.60 1.21 1.30 (11) fw / |fsmax| 2.54 3.14 2.84 2.76 2.46 (12) ft / fw 4.04 4.04 4.04 4.04 4.04 (13) Lw / fw 1.52 1.38 1.47 1.54 1.53 (14) Bfw / fw 0.41 0.41 0.46 0.40 0.45 (15) (R1r+R2f) / (R1r-R2f) 1.36 2.09 1.26 2.74 1.40 (16) |(1-βisw)×βisrw 2.44 2.27 2.53 2.10 2.40 (17) <![CDATA[|(1-βmBw 2 )×βmBrw 2 |]]> 3.34 4.19 4.35 3.93 3.68 (18) fw / f1 0.49 0.45 0.66 0.47 0.49 (19) ft / f1 2.00 1.82 2.68 1.89 1.98 (20) ft / |f2| 10.25 8.47 13.69 8.60 10.36 (21) fmw / |f2| 1.00 0.86 1.07 0.94 0.98 (22) fmt / |f2| 1.26 1.04 1.72 1.13 1.29 (23) v mp 81.61 81.59 94.66 81.59 81.61 (24) v 2p 70.39 70.42 65.44 70.42 70.44 (25) (R1f+R1r) / (R1f-R1r) -3.12 -4.37 -2.43 -4.62 -3.52 (26) v ave1p 76.01 76.01 78.16 76.01 76.03 (27) v ave2n 39.71 39.00 51.56 37.53 43.79 (28) v avemp 70.50 70.49 77.02 70.49 70.54 (29) visp 20.89 20.36 32.32 20.36 23.96 (30) fw / |f2| 2.54 2.10 3.39 2.13 2.57

[0271] As can be seen from the data above, the zoom lenses of Examples 1-5 are configured to have anti-vibration performance, a zoom ratio of 4x or more, achieve miniaturization and weight reduction, and have good correction of various aberrations, thereby achieving high optical performance. Furthermore, the zoom lenses of Examples 1-5 are suitable, for example, as telephoto zoom lenses.

[0272] Next, the imaging device according to the embodiments of the present invention will be described. Figure 12 and Figure 13 The diagram shows an external view of a camera 30, an imaging device according to an embodiment of the present invention. Figure 12 This is a stereoscopic view of camera 30 viewed from the front side. Figure 13 This is a perspective view of the camera 30 as seen from the rear side. The camera 30 is a so-called mirrorless digital camera, which can be detachably fitted with an interchangeable lens 20. The interchangeable lens 20 is configured to include a zoom lens 1 according to an embodiment of the present invention housed within a lens barrel.

[0273] The camera 30 includes a camera body 31, and a shutter button 32 and a power button 33 are provided on the upper surface of the camera body 31. Furthermore, an operation unit 34, an operation unit 35, and a display unit 36 ​​are provided on the back of the camera body 31. The display unit 36 ​​can display the captured image and the image existing within the field of view before shooting.

[0274] A camera body 31 has a camera aperture for light from the subject to enter at the center of the front. A bayonet 37 is provided at the position corresponding to the camera aperture, and the interchangeable lens 20 is mounted on the camera body 31 via the bayonet 37.

[0275] The camera body 31 contains an imaging element such as a CCD (Charge Coupled Device) or CMOS (Complementary Metal Oxide Semiconductor) that outputs an image signal corresponding to the image of the subject formed by the interchangeable lens 20, a signal processing circuit that processes the image signal output from the imaging element to generate an image, and a recording medium for recording the generated image. In the camera 30, still images or moving images can be captured by pressing the shutter button 32, and the image data obtained through this capture is recorded in the aforementioned recording medium.

[0276] The above description, through examples and embodiments, illustrates the technology of the present invention. However, the technology of the present invention is not limited to the above examples and embodiments, and various modifications are possible. For example, the radius of curvature, surface spacing, refractive index, dispersion coefficient, and aspherical coefficient of each lens are not limited to the values ​​shown in the above embodiments, and other values ​​may also be used.

[0277] Furthermore, the imaging device involved in the embodiments of the present invention is not limited to the examples described above. For example, it can also be configured as a camera other than a mirrorless camera, a film camera, a video camera, or other similar devices.

[0278] Symbol Explanation

[0279] 1-Zoom lens, 20-Interchangeable lens, 30-Camera, 31-Camera body, 32-Shutter button, 33-Power button, 34, 35-Operation unit, 36-Display unit, 37-Leg mount, DL1-Difference in the optical axis between the position of the first lens group at the telephoto end and the position of the first lens group at the wide-angle end, G1-First lens group, G2-Second lens group, G3-Third lens group, G4-Fourth lens group, G5-Fifth lens group, G6-Sixth lens group, L11~L6 1-Lens, Llist-Distance on the optical axis from the object-side lens surface of the entire system at the telephoto end to the object-side lens surface of the anti-vibration group at the telephoto end; Lw-Distance on the optical axis from the object-side lens surface of the entire system at the wide-angle end to the image-side lens surface of the entire system at the wide-angle end; ma, ta, wa-On-axis beam; mb, tb, wb-Beam at maximum angle; PP-Optical component; Sim-Image plane; St-Aperture; Z-Optical axis.

Claims

1. A zoom lens, comprising, from the object side toward the image side, a first lens group having positive refractive power, a second lens group having negative refractive power arranged sequentially with the first lens group, an intermediate group having positive refractive power including at least one lens group, and a subsequent group having negative refractive power including at least one lens group. The first lens group has 3 lenses, the second lens group has 4 lenses, the intermediate group has 6 lenses, and the subsequent group has 3 lenses, wherein The refractive powers of the first, second, and third lenses in the first lens group, from the object side to the image side, are negative, positive, and positive, respectively. The object-side and image-side surfaces of the first lens are convex and concave, respectively. The object-side and image-side surfaces of the second lens are both convex, and the object-side and image-side surfaces of the third lens are both convex and concave, respectively. The refractive powers of the first, second, third, and fourth lenses in the second lens group, from the object side to the image side, are positive, negative, positive, and negative, respectively. The object-side surface of the first lens is convex, the image-side surface of the second lens is concave, the object-side and image-side surfaces of the third lens are both convex and concave, respectively, and the object-side surface of the fourth lens is concave. The refractive powers of the first, second, and third lenses in the intermediate group, from the object side to the image side, are negative, positive, and negative, respectively. The refractive powers of the first, fourth, fifth, and sixth lenses are positive, negative, positive, positive, negative, and positive, respectively. The object-side and image-side surfaces of the first lens are convex and concave, respectively; the object-side and image-side surfaces of the second lens are convex and concave, respectively; the object-side and image-side surfaces of the third lens are both convex; the object-side surface of the fourth lens is convex; the object-side and image-side surfaces of the fifth lens are both concave; and the object-side and image-side surfaces of the sixth lens are both convex. In the subsequent group, from the object-side to the image-side, the refractive powers of the first, second, and third lenses are positive, negative, and positive, respectively. The object-side and image-side surfaces of the first lens are concave and convex, respectively; the object-side and image-side surfaces of the second lens are both concave; and the object-side and image-side surfaces of the third lens are both concave and convex, respectively. or, The first lens group has 3 lenses, the second lens group has 4 lenses, the intermediate group has 6 lenses, and the subsequent group has 4 lenses. In the first lens group, the refractive powers of the first, second, and third lenses (from the object side to the image side) are negative, positive, and positive, respectively. The object-side and image-side surfaces of the first lens are convex and concave, respectively. The object-side and image-side surfaces of the second lens are both convex, and the object-side and image-side surfaces of the third lens are both convex and concave, respectively. Similarly, in the second lens group, the refractive powers of the first, second, third, and fourth lenses (from the object side to the image side) are positive, negative, positive, and negative, respectively. The object-side and image-side surfaces of the first lens are both convex, the image-side surface of the second lens is concave, the object-side and image-side surfaces of the third lens are both convex and concave, and the object-side and image-side surfaces of the fourth lens are both concave and convex, respectively. In the intermediate group… The refractive powers of the 1st, 2nd, 3rd, 4th, 5th, and 6th lenses, from the object side to the image side, are positive, negative, positive, positive, negative, and positive, respectively. The object-side and image-side surfaces of the 1st lens are convex and concave, respectively; the object-side and image-side surfaces of the 2nd lens are convex and concave, respectively; the object-side and image-side surfaces of the 3rd lens are both convex; the object-side and image-side surfaces of the 4th lens are both convex; and the object-side and image-side surfaces of the 5th lens are both convex. The image-side surfaces of all lenses are concave, while the object-side and image-side surfaces of the 6th lens are convex. The refractive powers of the 1st, 2nd, 3rd, and 4th lenses in the subsequent group, from the object-side to the image-side, are negative, positive, negative, and positive, respectively. The object-side and image-side surfaces of the 1st lens are convex and concave, respectively; the image-side surface of the 2nd lens is convex; the object-side surface of the 3rd lens is concave; and the object-side and image-side surfaces of the 4th lens are concave and convex, respectively. or, The first lens group has 3 lenses, the second lens group has 5 lenses, the intermediate group has 5 lenses, and the subsequent group has 3 lenses. In the first lens group, the refractive powers of the first, second, and third lenses (from the object side to the image side) are negative, positive, and positive, respectively. The object-side and image-side surfaces of the first lens are convex and concave, respectively. The object-side and image-side surfaces of the second lens are both convex, and the object-side and image-side surfaces of the third lens are both convex and concave, respectively. Similarly, in the second lens group, the refractive powers of the first, second, third, fourth, and fifth lenses (from the object side to the image side) are positive, negative, negative, positive, and negative, respectively. The object-side and image-side surfaces of the first lens are both convex, the object-side and image-side surfaces of the second lens are both concave, the object-side and image-side surfaces of the third lens are both concave, and the object-side and image-side surfaces of the fourth lens are both convex and concave, respectively. The image-side surfaces of the first, second, third, fourth, and fifth lenses in the intermediate group are convex and concave, respectively. The object-side surface of the fifth lens is concave. The refractive powers of the first, second, third, fourth, and fifth lenses from the object-side to the image-side in the intermediate group are positive, positive, negative, positive, and negative, respectively. The object-side and image-side surfaces of the first lens are both convex; the object-side and image-side surfaces of the second lens are both convex; the object-side and image-side surfaces of the third lens are convex and concave, respectively; the object-side and image-side surfaces of the fourth lens are both convex; and the object-side and image-side surfaces of the fifth lens are both concave and convex, respectively. In the subsequent group, the refractive powers of the first, second, and third lenses from the object-side to the image-side are positive, negative, and positive, respectively. The object-side and image-side surfaces of the first lens are both concave and convex, respectively; the object-side and image-side surfaces of the second lens are both concave; and the object-side and image-side surfaces of the third lens are both convex. During zooming, the first lens group moves along the optical axis, the interval between the first lens group and the second lens group changes, the interval between the second lens group and the intermediate group changes, and the interval between the intermediate group and the subsequent groups changes. The second lens group, from the object side to the image side, includes, in sequence, a front group of the second lens group fixed during image jitter correction and an anti-vibration group with negative refractive power that moves along the direction intersecting the optical axis during image jitter correction. The difference in the optical axis direction between the position of the first lens group at the telephoto end and the position of the first lens group at the wide-angle end is defined as DL1. Let Lw be the distance along the optical axis from the lens surface closest to the object side of the entire system at the wide-angle end to the lens surface closest to the image side of the entire system at the wide-angle end. The lateral magnification of the anti-vibration group at the telephoto end, when focused on an object at infinity, is set to βist. When the combined lateral magnification of all lenses on the image side closer to the anti-vibration group at the telephoto end, in a state of focusing on an object at infinity, is set to βisrt, The zoom lens satisfies the following conditions (1) and (2). 0.4 < DL1 / Lw < 1 (1) 3.5<|(1-βist)×βisrt|<7 (2).

2. The zoom lens according to claim 1, wherein, The intermediate groups, from the object side toward the image side, sequentially include intermediate group A with positive refractive power and intermediate group B with positive refractive power. When the magnification is increased, the interval between the intermediate A group and the intermediate B group changes.

3. The zoom lens according to claim 2, wherein, During focusing, only the middle B group moves along the optical axis.

4. The zoom lens according to claim 3, wherein, When the focal length of the middle A group is set to fmA, When the focal length of the intermediate B group is set to fmB... The zoom lens satisfies the following condition (3). 0.5 < fmA / fmB < 2 (3).

5. The zoom lens according to claim 3 or 4, wherein, The optical axis spacing between the intermediate A group and the intermediate B group at the telephoto end when focusing on an object at infinity is set to DmAB. When the focal length of the intermediate B group is set to fmB... The zoom lens satisfies the following condition (4). 0.3 < DmAB / fmB < 1 (4).

6. The zoom lens according to claim 3 or 4, wherein, The lateral magnification of the intermediate B group at the telephoto end, with the focus on an object at infinity, is set to βmBt. When the combined lateral magnification of all lenses closer to the image side than the intermediate B group at the telephoto end, in a state of focusing on an object at infinity, is set to βmBrt, The zoom lens satisfies the following condition (5). 3<|(1-βmBt2)×βmBrt2|<10 (5).

7. The zoom lens according to any one of claims 1 to 4, wherein, Let L1ist be the distance along the optical axis from the lens surface closest to the object in the entire system at the telephoto end to the lens surface closest to the object in the anti-vibration group at the telephoto end. When the focal length of the first lens group is set to f1... The zoom lens satisfies the following condition (6). 0.57<L1ist / f1<0.7 (6).

8. The zoom lens according to any one of claims 1 to 4, wherein, The front group of the second lens group has positive refractive power.

9. The zoom lens according to any one of claims 1 to 4, wherein, With the wide-angle end focused on an object at infinity, the focal length of the entire system is set to fw. When the focal length of the vibration damping group is set to fis. The zoom lens satisfies the following condition (7). 1 < fw / |fis| < 5 (7).

10. The zoom lens according to any one of claims 1 to 4, wherein, With the wide-angle end focused on an object at infinity, the focal length of the entire system is set to fw. When the focal length of the intermediate group at the wide-angle end is set to fmw while focusing on an object at infinity, The zoom lens satisfies the following condition (8). 1 < fw / fmw < 5 (8).

11. The zoom lens according to any one of claims 1 to 4, wherein, The focal length of the entire system at the telephoto end, when focusing on an object at infinity, is set to ft. When the focal length of the intermediate group at the telephoto end is set to fmt while focusing on an object at infinity, The zoom lens satisfies the following condition (9). 5 < ft / fmt < 10 (9).

12. The zoom lens according to any one of claims 1 to 4, wherein, The focal length of the intermediate group at the telephoto end, when focusing on an object at infinity, is set to fmt. When the focal length of the intermediate group at the wide-angle end is set to fmw while focusing on an object at infinity, The zoom lens satisfies the following condition (10). 0.8<fmt / fmw<1.8 (10).

13. The zoom lens according to any one of claims 1 to 4, wherein, With the wide-angle end focused on an object at infinity, the focal length of the entire system is set to fw. When the focal length of the lens group with the strongest negative refractive power in the subsequent group is set to fsmax... The zoom lens satisfies the following condition (11). 1<fw / |fsmax|<4 (11).

14. The zoom lens according to any one of claims 1 to 4, wherein, The subsequent lens groups, arranged sequentially from the object side towards the image side, include a lens group with negative refractive power and a lens group with positive refractive power. When zooming in, the interval between the lens group with negative refractive power and the lens group with positive refractive power changes.

15. The zoom lens according to any one of claims 1 to 4, wherein, An aperture is disposed between the second lens group and the intermediate group.

16. The zoom lens according to any one of claims 1 to 4, wherein, The focal length of the entire system at the telephoto end, when focusing on an object at infinity, is set to ft. When the focal length of the entire system at the wide-angle end is set to fw while focusing on an object at infinity, The zoom lens satisfies the following condition (12). 3 < ft / fw < 5 (12).

17. The zoom lens according to any one of claims 1 to 4, wherein, When the focal length of the entire system at the wide-angle end is set to fw while focusing on an object at infinity, The zoom lens satisfies the following condition (13). 1.3 < Lw / fw < 1.6 (13).

18. The zoom lens according to any one of claims 1 to 4, wherein, With the wide-angle end focused on an object at infinity, the back focal length of the entire system's air-to-ground distance meter is set to Bfw. When the focal length of the entire system at the wide-angle end is set to fw while focusing on an object at infinity, The zoom lens satisfies the following condition (14). 0.35<Bfw / fw<0.55 (14).

19. The zoom lens according to any one of claims 1 to 4, wherein, The subsequent group includes a lens group that is fixed relative to the image plane when zoomed in, on the image-side closest to the image.

20. The zoom lens according to any one of claims 1 to 4, wherein, The radius of curvature of the lens surface closest to the image side of the first lens group is set as R1r. When the radius of curvature of the lens surface closest to the object in the second lens group is set to R2f, The zoom lens satisfies the following condition (15). 0.8<(R1r+R2f) / (R1r-R2f)<4(15).

21. A camera device comprising a zoom lens according to any one of claims 1 to 20.

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