Zoom lens and imaging device

Abstract

To provide a zoom lens which is compact, whose various aberrations are corrected and which maintains an excellent optical performance, and an imaging device equipped with the zoom lens.SOLUTION: A zoom lens comprises, in order from the object side to the image side, an object-side positive group which has positive refractive power, an object-side negative group which has negative refractive power, an intermediate group, and a final group. Each of the object-side positive group, object-side negative group, intermediate group, and final group includes at least one lens group. During zooming, all spacings between adjacent lens groups change, and the relative spacing between all lenses within each lens group is invariable. During focusing, all lenses within the object-side positive group and all lenses within the intermediate group are fixed relative to the image plane. The zoom lens satisfies prescribed conditional expressions.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The technology of the present disclosure relates to a zoom lens and an imaging device. [Background technology]

[0002] 2. Description of the Related Art Conventionally, a zoom lens that can be used in an imaging device such as a digital camera is known from the following Patent Document 1. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-043375 Summary of the Invention [Problem to be solved by the invention]

[0004] There is a demand for zoom lenses that are compact and have good optical performance with various aberrations corrected, and the level of these requirements is increasing year by year.

[0005] The present disclosure has been made in consideration of the above circumstances, and provides a zoom lens that is compact and maintains good optical performance with various aberrations corrected, and an imaging device equipped with this zoom lens. [Means for solving the problem]

[0006] A zoom lens according to one embodiment of the present disclosure comprises, in order from the object side to the image side, an object-side positive group having positive refractive power, an object-side negative group having negative refractive power, an intermediate group, and a final group, each of which includes at least one lens group, and during magnification change, all intervals between adjacent lens groups change while mutual intervals between all lenses in each lens group are constant, and during focusing, all lenses in the object-side positive group and all lenses in the intermediate group are fixed with respect to the image plane, 0.2 <Bfw / (fw×tanωw)<5 (1) The conditional expression (1) expressed by the following formula is satisfied. Here, the back focus in the air equivalent distance of the entire system when focused on an object at infinity at the wide-angle end is Bfw, the focal length of the entire system when focused on an object at infinity at the wide-angle end is fw, and the maximum half angle of view when focused on an object at infinity at the wide-angle end is ωw.

[0007] It is preferable that the object-side negative group includes a lens group having negative refractive power that is closest to the object among the lens groups having negative refractive power included in the zoom lens.

[0008] The final group preferably consists of one lens group.

[0009] The intermediate group preferably includes at least three lenses.

[0010] When the paraxial radius of curvature of the object-side surface of the negative lens closest to the object among the negative lenses included in the object-side negative group is Rnf, and the paraxial radius of curvature of the image-side surface of the negative lens closest to the object among the negative lenses included in the object-side negative group is Rnr, the zoom lens of the above aspect has the following characteristics: 0.02<(Rnf-Rnr) / (Rnf+Rnr)<3 (2) It is preferable to satisfy conditional expression (2) expressed as follows:

[0011] During zooming, the lens unit closest to the object side of the object-side positive group may be configured to move.

[0012] The zoom lens includes at least one focusing group that moves during focusing, and among the focusing groups included in the zoom lens, the focusing group closest to the object side preferably has negative refractive power.

[0013] The object-side negative group includes at least two negative lenses, and it is preferable that, among the negative lenses included in the object-side negative group, the image-side surface of the negative lens closest to the object is concave, and that, among the negative lenses included in the object-side negative group, the object-side surface of the negative lens closest to the image is concave.

[0014] It is preferable that the intermediate group includes at least one lens group having positive refractive power, and that the lens group having positive refractive power included in the intermediate group and closest to the object side includes at least two positive lenses. 20 <(νMp1+νMp2) / 2<100 (3) It is preferable to satisfy conditional expression (3) expressed as follows. Here, the Abbe number based on the d-line of the positive lens closest to the object among the positive lenses included in the intermediate group is denoted as νMp1. The Abbe number based on the d-line of the positive lens second from the object among the positive lenses included in the intermediate group is denoted as νMp2.

[0015] It is preferable that the intermediate group includes at least two lens groups whose spacing from adjacent lens groups changes during magnification variation.

[0016] It is preferable that the intermediate group includes at least one lens group having positive refractive power, and that among the lens groups having positive refractive power included in the intermediate group, the lens group having positive refractive power closest to the object side includes two positive lenses in succession from the closest to the object side to the image side.

[0017] The intermediate group includes at least one lens group having positive refractive power, and it is preferable that the lens group having positive refractive power closest to the object side among the lens groups having positive refractive power included in the intermediate group includes at least two positive lenses. In this configuration, it is preferable that the object-side surface of the positive lens closest to the object side among the positive lenses included in the lens group having positive refractive power closest to the object side of the intermediate group is a convex surface.

[0018] It is preferable that the object-side negative lens group includes at least four lenses.

[0019] When the maximum aperture F-number when focused on an object at infinity at the wide-angle end is Fnow, the zoom lens of the above embodiment has the following characteristics: 2 <Fnow<4.8 (4) It is preferable to satisfy conditional expression (4) expressed as follows:

[0020] Of the lens groups included in the intermediate group, the lens group closest to the image side may be configured to have positive refractive power.

[0021] If the focal length of the object-side positive group at the wide-angle end is fGPw, the zoom lens of the above embodiment has the following characteristics: 0.05 <fw / fGPw<2.5 (5) It is preferable to satisfy conditional expression (5) expressed as follows:

[0022] If the focal length of the entire system at the telephoto end when focused on an object at infinity is ft and the focal length of the object-side positive group at the wide-angle end is fGPw, the zoom lens of the above embodiment has the following characteristics: 0.4 <ft / fGPw<4.5 (6) It is preferable to satisfy conditional expression (6) expressed as follows:

[0023] It is preferable that the object-side negative group includes a lens group in which a biconvex air lens is formed.

[0024] The object-side negative group may include a lens group having negative refractive power, and may be configured such that, during focusing, all or a part of the lens group having negative refractive power in the object-side negative group moves along the optical axis.

[0025] During focusing, all or part of the final group may be arranged to move along the optical axis.

[0026] The lens unit closest to the image side of the final group may be configured to move during magnification change.

[0027] An imaging device according to another aspect of the present disclosure includes the zoom lens according to the above aspect of the present disclosure.

[0028] In addition, in this specification, "consisting of" and "consisting of" are intended to mean that, in addition to the listed components, the following may be included: a lens that has substantially no refractive power, optical elements other than lenses such as an aperture, a filter, and a cover glass, and mechanical parts such as a lens flange, a lens barrel, an image sensor, and an image stabilization mechanism.

[0029] In this specification, "the lens group having positive refractive power" and "the lens group has positive refractive power" mean that the lens group as a whole has positive refractive power. Similarly, "the lens group having negative refractive power" and "the lens group has negative refractive power" mean that the lens group as a whole has negative refractive power. In this specification, the "lens group", "focusing group", and "anti-vibration group" are not limited to configurations consisting of multiple lenses, and may be configured to consist of only one lens.

[0030] A compound aspherical lens (a lens in which a lens (e.g. a spherical lens) and an aspherical film formed on that lens are integrally constructed and function as a single aspherical lens overall) is not considered a cemented lens, but is treated as a single lens. Unless otherwise specified, the radius of curvature, sign of refractive power, and surface shape of lenses including aspheric surfaces are those in the paraxial region. The sign of the radius of curvature of a surface with a convex shape facing the object side is positive, and the sign of the radius of curvature of a surface with a convex shape facing the image side is negative.

[0031] In this specification, "whole system" means a zoom lens. "Back focus in air equivalent distance" is the air equivalent distance on the optical axis from the lens surface of the whole system closest to the image to the image plane. "Focal length" used in the conditional expressions is the paraxial focal length. "Distance on the optical axis" used in the conditional expressions is a geometric distance unless otherwise specified. Values ​​used in the conditional expressions are values ​​based on the d-line when focused on an object at infinity, unless otherwise specified. Effect of the Invention

[0032] According to the present disclosure, it is possible to provide a zoom lens that is compact and maintains good optical performance with various aberrations corrected, and an imaging device equipped with this zoom lens. [Brief description of the drawings]

[0033] [Figure 1] 1A and 1B correspond to the zoom lens of Example 1 and are diagrams showing a cross-sectional view of the configuration of a zoom lens according to an embodiment and a movement locus thereof. [Diagram 2] FIG. 2 is a diagram showing the configuration and light beams in each zoom state of the zoom lens in FIG. 1, and is a diagram for explaining symbols in conditional expressions. [Diagram 3] 3A to 3C are diagrams showing various aberrations of the zoom lens of Example 1. [Figure 4] 11A and 11B are diagrams illustrating a cross-sectional view of the configuration of a zoom lens according to a second embodiment and a movement locus thereof. [Diagram 5] 6A to 6C are diagrams showing various aberrations of the zoom lens of Example 2. [Figure 6] 11A and 11B are diagrams illustrating a cross-sectional view of the configuration of a zoom lens according to a third embodiment and a movement locus thereof. [Figure 7] 11A and 11B are diagrams illustrating the configuration and light beams in each magnification change state of a zoom lens according to a third embodiment. [Figure 8] 11A and 11B are diagrams illustrating a cross-sectional view of the configuration of a zoom lens according to a fourth embodiment and a movement locus thereof. [Figure 9] 11A to 11C are diagrams showing various aberrations of the zoom lens of Example 4. [Figure 10] 13A and 13B are diagrams illustrating a cross-sectional view of the configuration of a zoom lens according to a fifth embodiment and a movement locus thereof. [Figure 11] 13A to 13C are diagrams showing various aberrations of the zoom lens of Example 5. [Figure 12] 13A and 13B are diagrams illustrating a cross-sectional view of the configuration of a zoom lens according to a sixth embodiment and a movement locus thereof. [Figure 13] 13A to 13C are diagrams showing various aberrations of the zoom lens of Example 6. [Figure 14] 13A and 13B are diagrams illustrating a cross-sectional view and a movement locus of a zoom lens according to a seventh embodiment. [Figure 15] 13A to 13C are diagrams showing various aberrations of the zoom lens of Example 7. [Figure 16]13A and 13B are diagrams illustrating a cross-sectional view of the configuration of a zoom lens according to an eighth embodiment and a movement locus thereof. [Figure 17] 13A to 13C are diagrams showing various aberrations of the zoom lens of Example 8. [Figure 18] 13A and 13B are diagrams illustrating a cross-sectional view and a movement locus of a zoom lens according to a ninth embodiment. [Figure 19] 13A to 13C are diagrams showing various aberrations of the zoom lens of Example 9. [Figure 20] 13A and 13B are diagrams illustrating a cross-sectional view and a movement locus of a zoom lens according to a tenth embodiment. [Figure 21] 21A to 21C are diagrams showing various aberrations of the zoom lens of Example 10. [Figure 22] 13A and 13B are diagrams illustrating a cross-sectional view of the configuration of a zoom lens according to an eleventh embodiment and a movement locus thereof. [Diagram 23] 13A to 13C are diagrams showing various aberrations of the zoom lens of Example 11. [Figure 24] 13A and 13B are diagrams illustrating a cross-sectional view and a movement locus of a zoom lens according to a twelfth embodiment. [Diagram 25] 23A to 23C are diagrams showing various aberrations of the zoom lens of Example 12. [Figure 26] 13A and 13B are diagrams illustrating a cross-sectional view and a movement locus of a zoom lens according to a thirteenth embodiment. [Figure 27] 23A to 23C are diagrams showing various aberrations of the zoom lens of Example 13. [Figure 28] 13A and 13B are diagrams illustrating a cross-sectional view of the configuration of a zoom lens according to a fourteenth embodiment and a movement locus thereof. [Figure 29] 23A to 23C are diagrams showing various aberrations of the zoom lens of Example 14. [Diagram 30] 15A and 15B are diagrams illustrating a cross-sectional view of the configuration of a zoom lens according to a fifteenth embodiment and a movement locus thereof. [Diagram 31] 23A to 23C are diagrams showing various aberrations of the zoom lens of Example 15. [Diagram 32] 23A and 23B are diagrams showing a cross-sectional view and a movement locus of a zoom lens according to a sixteenth embodiment. [Diagram 33] 23A to 23C are diagrams showing various aberrations of the zoom lens of Example 16. [Diagram 34] 23A and 23B are diagrams showing a cross-sectional view and a movement locus of a zoom lens according to a seventeenth embodiment. [Diagram 35]21A to 21C are diagrams showing various aberrations of the zoom lens of Example 17. [Diagram 36] 23A and 23B are diagrams showing a cross-sectional view and a movement locus of a zoom lens according to an eighteenth embodiment. [Figure 37] 23A to 23C are diagrams showing various aberrations of the zoom lens of Example 18. [Figure 38] 23A and 23B are diagrams showing a cross-sectional view and a movement locus of a zoom lens according to a nineteenth embodiment. [Figure 39] 23A to 23C are diagrams showing various aberrations of the zoom lens of Example 19. [Diagram 40] 23A and 23B are diagrams showing a cross-sectional view and a movement locus of a zoom lens according to a twentieth embodiment of the present invention. [Diagram 41] 23A to 23C are diagrams showing various aberrations of the zoom lens of Example 20. [Diagram 42] 23A and 23B are diagrams showing a cross-sectional view and a movement locus of a zoom lens according to a twenty-first embodiment. [Diagram 43] 23A to 23C are diagrams showing various aberrations of the zoom lens of Example 21. [Diagram 44] 23A and 23B are diagrams showing a cross-sectional view and a movement locus of a zoom lens according to a twenty-second embodiment. [Diagram 45] 23A to 23C are diagrams showing various aberrations of the zoom lens of Example 22. [Figure 46] 23A and 23B are diagrams showing a cross-sectional view and a movement locus of a zoom lens according to a twenty-third embodiment. [Figure 47] 23A to 23C are diagrams showing various aberrations of the zoom lens of Example 23. [Figure 48] 23A and 23B are diagrams showing a cross-sectional view and a movement locus of a zoom lens according to a twenty-fourth embodiment. [Figure 49] 23A to 23C are diagrams showing various aberrations of the zoom lens of Example 24. [Figure 50] 23A and 23B are diagrams showing a cross-sectional view and a movement locus of a zoom lens according to a twenty-fifth embodiment. [Figure 51] 23A to 23C are diagrams showing various aberrations of the zoom lens of Example 25. [Figure 52] 23A and 23B are diagrams showing a cross-sectional view and a movement locus of a zoom lens according to a twenty-sixth embodiment. [Figure 53] 23A to 23C are diagrams showing various aberrations of the zoom lens of Example 26. [Figure 54]23A and 23B are diagrams showing a cross-sectional view and a movement locus of a zoom lens according to a twenty-seventh embodiment. [Figure 55] 23A to 23C are diagrams showing various aberrations of the zoom lens of Example 27. [Figure 56] 23A and 23B are diagrams showing a cross-sectional view and a movement locus of a zoom lens according to a twenty-eighth embodiment. [Figure 57] 23A to 23C are diagrams showing various aberrations of the zoom lens of Example 28. [Figure 58] 1 is a perspective view of the front side of an imaging device according to an embodiment. [Figure 59] FIG. 2 is a perspective view of the rear side of the imaging device according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0034] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[0035] FIG. 1 shows a cross-sectional view of the configuration of a zoom lens according to an embodiment of the present disclosure and a movement trajectory. FIG. 2 shows a cross-sectional view of the configuration of the zoom lens in FIG. 1 together with a light beam. In FIG. 2, the light beam is shown as an axial light beam and a light beam at the maximum half angle of view in each state. In FIG. 1 and FIG. 2, the wide-angle end state is shown in the upper row labeled "Wide" and the telephoto end state is shown in the lower row labeled "Tele". The example shown in FIG. 1 and FIG. 2 corresponds to the zoom lens of Example 1 described later. In FIG. 1 and FIG. 2, a state in which the lens is focused on an object at infinity is shown, with the left side being the object side and the right side being the image side. The following description will be mainly made with reference to FIG. 1, and FIG. 2 will be referred to as necessary.

[0036] In Fig. 1, assuming that the zoom lens is applied to an imaging device, an example is shown in which a parallel plate-like optical member PP is disposed between the zoom lens and an image surface Sim. The optical member PP is a member assuming various filters and / or cover glass, etc. The various filters are low-pass filters, infrared cut filters, and / or filters that cut off specific wavelength ranges, etc. The optical member PP is a member that does not have refractive power. It is also possible to configure an imaging device without the optical member PP.

[0037] The zoom lens of the present disclosure comprises, in order from the object side to the image side along the optical axis Z, an object-side positive group GP having positive refractive power, an object-side negative group GN having negative refractive power, an intermediate group GM, and a final group GE. This configuration is advantageous for suppressing various aberrations over the entire range of magnification.

[0038] The object-side positive group GP, the object-side negative group GN, the intermediate group GM, and the final group GE each include at least one lens group. When the magnification is changed, the distances between all of the adjacent lens groups change, and the distances between all of the lenses in each lens group remain constant. By having each of the object-side positive group GP, the object-side negative group GN, the intermediate group GM, and the final group GE include at least one lens group, this is advantageous in suppressing aberration fluctuations when the magnification is changed.

[0039] In this specification, a lens group is defined as a group whose distance in the optical axis direction between adjacent groups changes when the magnification is changed. When the magnification is changed, the distance between adjacent lenses in one lens group does not change. In other words, a "lens group" is a component of a zoom lens, and is a part including at least one lens separated by an air gap that changes when the magnification is changed. When the magnification is changed, each lens group is moved or fixed. Note that the "lens group" may include components other than lenses that do not have refractive power, such as an aperture stop St.

[0040] As an example, each group of the zoom lens shown in FIG. 2 is configured as follows. The object-side positive group GP is made up of one lens group. The lens groups constituting the object-side positive group GP are made up of three lenses, lenses L11 to L13, in order from the object side to the image side. The object-side negative group GN is made up of one lens group. The lens groups constituting the object-side negative group GN are made up of five lenses, lenses L21 to L25, in order from the object side to the image side. The middle group GM is made up of two lens groups, the first M lens group GM1 and the second M lens group GM2, in order from the object side to the image side. The first M lens group GM1 is made up of an aperture stop St and four lenses, lenses L31 to L34, in order from the object side to the image side. The second M lens group GM2 is made up of three lenses, lenses L41 to L43, in order from the object side to the image side. The final group GE is made up of one lens group. The lens group constituting the final group GE is composed of three lenses, lenses L51 to L53, in that order from the object side to the image side. Note that the aperture stop St shown in Figures 1 and 2 does not indicate the size or shape, but indicates the position in the optical axis direction.

[0041] In the example of Fig. 1, during magnification change, the object-side positive group GP, the object-side negative group GN, the first M lens group GM1, and the second M lens group GM2 move along the optical axis Z while changing the intervals between the adjacent lens groups, and the final group GE is fixed with respect to the image surface Sim. In Fig. 1, between the Wide and Tele views, for each lens group that moves during magnification change, a solid arrow shows the approximate movement trajectory during magnification change from the wide-angle end to the telephoto end, and for the lens groups that are fixed during magnification change, a straight dotted line in the vertical direction is shown.

[0042] The object-side positive group GP may be configured to consist of one lens group, which is advantageous for making the lens compact.

[0043] The number of lenses included in the object-side positive group GP is preferably 3 or less. Since the object-side positive group GP is a lens group on the object side and has a large outer diameter, constituting the object-side positive group GP with 3 or less lenses is advantageous for weight reduction.

[0044] It is preferable that the lens unit closest to the object side of the object-side positive group GP moves when changing magnification. By configuring the lens unit closest to the object side of the zoom lens to move when changing magnification, it is advantageous for suppressing various aberrations when changing magnification.

[0045] The object-side negative group GN preferably includes the lens group having the negative refractive power that is the closest to the object among the lens groups having the negative refractive power included in the zoom lens. That is, it is preferable that all the lens groups included in the object-side positive group GP are lens groups having positive refractive power. By configuring the object-side positive group GP, which is the group closest to the object, as described above, it is advantageous for size reduction.

[0046] It is preferable that the object-side negative group GN includes at least four lenses, which is advantageous for improving performance.

[0047] It is preferable that the object-side negative group GN includes at least two negative lenses. In this case, it is preferable that the image-side surface of the negative lens closest to the object among the negative lenses included in the object-side negative group GN is a concave surface, and that the object-side surface of the negative lens closest to the image among the negative lenses included in the object-side negative group GN is a concave surface. In this case, it is advantageous for correcting the curvature of field.

[0048] It is preferable that the object-side negative group GN includes a lens group in which a biconvex air lens is formed. In this case, it is advantageous to suppress the curvature of field. In this specification, the air space between two opposing lens surfaces is regarded as a lens with a refractive index of 1, and this air space is called an air lens. In the example of FIG. 2, a biconvex air lens is formed by the image side surface of the lens L21 and the object side surface of the lens L22, a biconvex air lens is formed by the image side surface of the lens L23 and the object side surface of the lens L24, and a biconvex air lens is formed by the image side surface of the lens L24 and the object side surface of the lens L25.

[0049] In this specification, among the lens groups having negative refractive power included in the zoom lens, the lens group having negative refractive power closest to the object side is referred to as the first negative lens group. For example, in the example of FIG. 1, the object-side negative lens group GN is the first negative lens group. Among the lens groups having positive refractive power closer to the image side than the first negative lens group, the lens group having positive refractive power closest to the object side is preferably disposed closest to the object side of the intermediate group GM. In this case, it is advantageous to reduce the size of the intermediate group GM.

[0050] It is preferable that the middle group GM includes at least three lenses. This is advantageous for suppressing various aberrations during zooming. To suppress various aberrations during zooming, it is more preferable that the middle group GM includes at least four lenses, and even more preferable that it includes at least five lenses.

[0051] It is preferable that the middle group GM includes at least two lens groups whose spacing from adjacent lens groups changes during zooming, which makes it easier to suppress aberration fluctuations during zooming.

[0052] It is preferable that the intermediate group GM includes at least one lens group having a positive refractive power. In this specification, the lens group having a positive refractive power that is the most object side among the lens groups having a positive refractive power included in the intermediate group GM is referred to as the first intermediate positive lens group. For example, in the example of FIG. 1, the first M lens group GM1 is the first intermediate positive lens group. It is preferable that the first intermediate positive lens group includes at least two positive lenses. In this case, the positive refractive power of the first intermediate positive lens group can be shared by two or more positive lenses, which is advantageous for suppressing various aberrations. It is preferable that the first intermediate positive lens group includes two positive lenses in succession from the most object side to the image side. In this case, it is advantageous for correcting various aberrations, especially spherical aberration. In a configuration in which the first intermediate positive lens group includes at least two positive lenses, it is preferable that the object side surface of the most object side positive lens among the positive lenses included in the first intermediate positive lens group is a convex surface. In this case, it is advantageous for correcting spherical aberration.

[0053] Of the lens groups included in the intermediate group GM, the lens group closest to the image side may be configured to have positive refractive power. By arranging a lens group having positive refractive power closer to the object side than the final group GE, it is advantageous to reduce the lens outer diameter of the final group GE. In particular, by arranging a lens group having positive refractive power adjacent to the object side of the final group GE, it is advantageous to reduce the lens outer diameter of the final group GE.

[0054] It is preferable that the final group GE consists of one lens group, which makes it easier to shorten the overall length of the optical system.

[0055] During magnification change, it is preferable that the final lens group GE is fixed relative to the image plane Sim. If the final lens group GE does not move during magnification change, it becomes easier to prevent dust and the like from entering the inside of the zoom lens.

[0056] 1, the aperture diaphragm St is included in the middle group GM. By disposing the aperture diaphragm St in the middle group GM, which has a relatively small outer diameter, the diaphragm unit can be made compact, which makes it easier to make the entire lens apparatus compact.

[0057] The zoom lens of the present disclosure preferably includes at least one focusing group that moves during focusing. Hereinafter, the group that moves along the optical axis Z during focusing is referred to as the focusing group. Focusing is performed by the movement of the focusing group. As an example, in the example of FIG. 1, the focusing group is composed of three lenses, lenses L21 to L23 of the object-side negative group GN. In FIG. 1, under the lens corresponding to the focusing group in the lower diagram, a left-right arrow indicating the direction of movement during focusing from an object at infinity to the nearest object is written in parentheses. Note that the focusing group functions over the entire range of magnification including the wide-angle end state, but in FIG. 1, the above arrow is written only in the lower diagram to avoid cluttering the diagram.

[0058] When the object-side negative group GN includes a lens group having negative refractive power, all or part of the lens group having negative refractive power in the object-side negative group GN may be configured to move along the optical axis Z during focusing. The lens groups in the object-side negative group GN have relatively small lens outer diameters. By using all or part of the lens group with a small lens outer diameter as the focusing group, it becomes easier to reduce the diameter of the entire zoom lens.

[0059] In the zoom lens of the present disclosure, all lenses in the object-side positive group GP are fixed relative to the image surface Sim during focusing. By using another group as the focusing group instead of the object-side positive group GP, which has a large lens outer diameter, the outer diameter of the focusing group can be made small, making it easier to reduce the weight of the focusing group, and thus reducing the load on the drive mechanism.

[0060] Furthermore, in the zoom lens of the present disclosure, all lenses in the middle group GM are fixed relative to the image surface Sim during focusing. Using another group as the focusing group, rather than the middle group GM which has a large diameter of the axial light beam, is advantageous in suppressing fluctuations in spherical aberration during focusing.

[0061] Although the zoom lens in the example of FIG. 1 includes only one focusing group, the zoom lens of the present disclosure may be configured to include multiple focusing groups. In the following, of the focusing groups included in the zoom lens, the focusing group closest to the object side will be referred to as the first focusing group. For example, in the example of FIG. 1, the first focusing group is made up of lenses L21 to L23. It is preferable that the first focusing group has negative refractive power. In this case, it is advantageous to reduce the amount of movement during focusing.

[0062] It is preferable that the first focusing group includes a negative lens with a concave surface facing the direction of movement when focusing from an infinite object to a close object. In this case, it is advantageous to suppress the variation of the field curvature when focusing on a close object. For example, the first focusing group in the example of FIG. 1 moves toward the image side when focusing from an infinite object to a close object. And, both lenses L21 and L22 in the example of FIG. 1 are negative lenses with a concave surface facing the image side.

[0063] The zoom lens of the present disclosure preferably includes an anti-vibration group that moves during image blur correction. Hereinafter, a group that moves in a direction intersecting the optical axis Z during image blur correction is referred to as the anti-vibration group. Image blur correction is performed by the movement of the anti-vibration group. As an example, in the example of FIG. 1, the anti-vibration group is composed of the second M lens group GM2. In FIG. 1, an arrow indicating a downward direction is written in parentheses under the lens corresponding to the anti-vibration group in the lower diagram. Note that the anti-vibration group functions over the entire range of magnification including the wide-angle end state, but in FIG. 1, the above arrow is written only in the lower diagram to avoid cluttering the diagram.

[0064] The vibration isolation group may be configured to be located closer to the image side than the focusing group. By using a lens with a relatively small outer diameter that is located closer to the image side than the focusing group as the vibration isolation group, the vibration isolation mechanism can also be made smaller, making it easier to make the entire lens device smaller.

[0065] The vibration reduction group may be configured so as to be included in the intermediate group GM. By disposing the vibration reduction group in the intermediate group GM, which has a comparatively small outer lens diameter, the vibration reduction mechanism can also be made compact, making it easier to make the entire lens apparatus compact.

[0066] The image stabilization group may be configured to include at least one positive lens and at least one negative lens, which is advantageous for reducing color bleeding during image blur correction.

[0067] Next, preferred and possible configurations for the conditional expressions of the zoom lens of the present disclosure will be described. In the following description of the conditional expressions, in order to avoid redundant explanations, the same symbols are used for elements with the same definitions, and some of the duplicated explanations of the symbols are omitted. In addition, in the following, in order to avoid redundant explanations, the "zoom lens of the present disclosure" will also be simply referred to as the "zoom lens."

[0068] It is preferable that the zoom lens satisfies the following conditional expression (1). Here, the back focus in the air equivalent distance of the entire system when focused on an object at infinity at the wide-angle end is Bfw. The focal length of the entire system when focused on an object at infinity at the wide-angle end is fw. The maximum half angle of view when focused on an object at infinity at the wide-angle end is ωw. As an example, FIG. 2 shows the above maximum half angle of view ωw. By ensuring that the corresponding value of conditional expression (1) is not equal to or less than the lower limit, it is advantageous to ensure the amount of peripheral light. By ensuring that the corresponding value of conditional expression (1) is not equal to or more than the upper limit, it is advantageous to shorten the overall length of the optical system. 0.2 <Bfw / (fw×tanωw)<5 (1)

[0069] In order to obtain better characteristics, the lower limit of conditional formula (1) is more preferably 0.3, more preferably 0.5, more preferably 0.7, more preferably 0.8, and even more preferably 0.9. The upper limit of conditional formula (1) is more preferably 4, more preferably 3, more preferably 2, more preferably 1.7, and even more preferably 1.

[0070] It is preferable that the zoom lens satisfies the following conditional expression (2). Here, the paraxial radius of curvature of the object-side surface of the negative lens closest to the object among the negative lenses included in the object-side negative group GN is Rnf. The paraxial radius of curvature of the image-side surface of the negative lens closest to the object among the negative lenses included in the object-side negative group GN is Rnr. By ensuring that the corresponding value of conditional expression (2) is not equal to or less than the lower limit, it is advantageous for suppressing astigmatism from the wide-angle end to the telephoto end. By ensuring that the corresponding value of conditional expression (2) is not equal to or more than the upper limit, it is advantageous for suppressing distortion and field curvature at the wide-angle end. 0.02<(Rnf-Rnr) / (Rnf+Rnr)<3 (2)

[0071] In order to obtain better characteristics, the lower limit of conditional formula (2) is more preferably 0.04, more preferably 0.1, more preferably 0.3, more preferably 0.5, more preferably 0.62, more preferably 0.68, and more preferably 0.75. The upper limit of conditional formula (2) is more preferably 2.5, more preferably 2, more preferably 1.5, more preferably 1.17, more preferably 1.13, more preferably 1.1, and more preferably 1.

[0072] In a configuration in which the middle group GM includes at least one lens group having positive refractive power and the first middle positive lens group includes at least two positive lenses, it is preferable that the zoom lens satisfies the following conditional formula (3). Here, the Abbe number based on the d-line of the positive lens closest to the object among the positive lenses included in the middle group GM is set to νMp1. The Abbe number based on the d-line of the positive lens second from the object among the positive lenses included in the middle group GM is set to νMp2. By making the corresponding value of conditional formula (3) not equal to or less than the lower limit, it is possible to prevent the axial chromatic aberration at the wide-angle end from being undercorrected, which is advantageous for improving performance. By making the corresponding value of conditional formula (3) not equal to or more than the upper limit, it is possible to prevent the axial chromatic aberration at the wide-angle end from being overcorrected, which is advantageous for improving performance. 20 <(νMp1+νMp2) / 2<100 (3)

[0073] In order to obtain better characteristics, the lower limit of conditional formula (3) is more preferably 27, even more preferably 32, even more preferably 39, even more preferably 45, even more preferably 50, even more preferably 60, and even more preferably 70. The upper limit of conditional formula (3) is more preferably 90, and even more preferably 80.

[0074] It is preferable that the zoom lens satisfies the following conditional expression (4). Here, Fnow is the maximum F-number when focused on an object at infinity at the wide-angle end. By ensuring that the corresponding value of conditional expression (4) is not below the lower limit, it is advantageous for the overall zoom lens to be compact. By ensuring that the corresponding value of conditional expression (4) is not above the upper limit, it is advantageous for a large aperture. 2 <Fnow<4.8 (4)

[0075] In order to obtain better characteristics, the lower limit of condition (4) should more preferably be 2.3, even more preferably be 2.4, and even more preferably be 2.5.The upper limit of condition (4) should more preferably be 4.5, even more preferably be 4, and even more preferably be 3.9.

[0076] It is preferable that the zoom lens satisfies the following conditional expression (5). Here, the focal length of the object-side positive group GP at the wide-angle end is fGPw. By ensuring that the corresponding value of conditional expression (5) is not below the lower limit, the refractive power of the object-side positive group GP does not become too weak, which is advantageous for miniaturizing the lens group closest to the object. By ensuring that the corresponding value of conditional expression (5) is not above the upper limit, the refractive power of the object-side positive group GP does not become too weak, which is advantageous for suppressing aberration fluctuations during magnification. 0.05 <fw / fGPw<2.5 (5)

[0077] In order to obtain better characteristics, the lower limit of conditional formula (5) is more preferably 0.1, more preferably 0.13, more preferably 0.15, more preferably 0.16, more preferably 0.18, more preferably 0.2, and more preferably 0.35. The upper limit of conditional formula (5) is more preferably 2, more preferably 1.5, more preferably 1.25, more preferably 1, more preferably 0.85, more preferably 0.75, and more preferably 0.55.

[0078] It is preferable that the zoom lens satisfies the following conditional expression (6). Here, ft is the focal length of the entire system when focused on an object at infinity at the telephoto end. By ensuring that the corresponding value of conditional expression (6) is not below the lower limit, the refractive power of the object-side positive group GP does not become too weak, which is advantageous for miniaturizing the lens group closest to the object. By ensuring that the corresponding value of conditional expression (6) is not above the upper limit, the refractive power of the object-side positive group GP does not become too weak, which is advantageous for suppressing aberration fluctuations during magnification. 0.4 <ft / fGPw<4.5 (6)

[0079] In order to obtain better characteristics, the lower limit of conditional formula (6) is more preferably 0.5, more preferably 0.6, more preferably 0.7, more preferably 0.8, and even more preferably 1.1. The upper limit of conditional formula (6) is more preferably 4, more preferably 3.5, more preferably 3, more preferably 2.7, and even more preferably 1.5.

[0080] It is preferable that the zoom lens satisfies the following conditional expression (7). Here, fGMp is the focal length of the lens group having the strongest positive refractive power among the lens groups included in the middle group GM. By ensuring that the corresponding value of conditional expression (7) is not below the lower limit, the refractive power of the middle group GM does not become too weak, which is advantageous for size reduction. By ensuring that the corresponding value of conditional expression (7) is not above the upper limit, the refractive power of the middle group GM does not become too strong, which is advantageous for suppressing aberration fluctuations during magnification change. 0.3 <fw / fGMp<4 (7)

[0081] In order to obtain better characteristics, the lower limit of conditional formula (7) is more preferably 0.35, even more preferably 0.4, even more preferably 0.45, and even more preferably 0.5. The upper limit of conditional formula (7) is more preferably 3.5, even more preferably 3, even more preferably 2.8, even more preferably 2, even more preferably 1.8, and even more preferably 1.3.

[0082] It is preferable for the zoom lens to satisfy the following conditional expression (8). Here, the focal length of the middle group GM at the wide-angle end is fGMw. By ensuring that the corresponding value of conditional expression (8) is not below the lower limit, the refractive power of the middle group GM does not become too weak, which is advantageous for size reduction. By ensuring that the corresponding value of conditional expression (8) is not above the upper limit, the refractive power of the middle group GM does not become too strong, which is advantageous for suppressing aberration fluctuations during magnification change. 0.1 <fw / fGMw<3 (8)

[0083] In order to obtain better characteristics, the lower limit of conditional formula (8) is more preferably 0.2, more preferably 0.25, more preferably 0.3, more preferably 0.4, more preferably 0.5, more preferably 0.6, and more preferably 0.7. The upper limit of conditional formula (8) is more preferably 2.5, more preferably 2, more preferably 1.8, more preferably 1.6, more preferably 1.2, more preferably 1, and more preferably 0.8.

[0084] It is preferable that the zoom lens satisfies the following conditional expression (9). Here, the focal length of the final group GE when focused on an object at infinity at the wide-angle end is taken as fGEw. Ensuring that the corresponding value of conditional expression (9) is not equal to or less than the lower limit thereof is advantageous for suppressing various aberrations throughout the entire range of magnification changes. Ensuring that the corresponding value of conditional expression (9) is not equal to or greater than the upper limit thereof is advantageous for reducing the error sensitivity of the final group GE during assembly. -3 <fw / fGEw<3 (9)

[0085] In order to obtain better characteristics, the lower limit of conditional formula (9) should more preferably be set to -2.5, more preferably to -2, even more preferably to -1.5, and even more preferably to -1. The upper limit of conditional formula (9) should more preferably be set to 2.5, more preferably to 2.3, even more preferably to 2, even more preferably to 1.7, even more preferably to 1.5, and even more preferably to 1.2.

[0086] It is preferable for the zoom lens to satisfy the following conditional expression (10). Here, the focal length of the first focusing group is ffoc. By ensuring that the corresponding value of conditional expression (10) is not below the lower limit, the amount of movement during focusing can be reduced, which is advantageous for miniaturization and faster focusing. By ensuring that the corresponding value of conditional expression (10) is not above the upper limit, the refractive power of the focusing group does not become too strong, which is advantageous for suppressing aberration fluctuations during focusing. 0.05 <fw / |ffoc|<3.5 (10)

[0087] In order to obtain better characteristics, the lower limit of conditional formula (10) is more preferably 0.08, more preferably 0.12, more preferably 0.16, more preferably 0.25, more preferably 0.3, more preferably 0.4, and more preferably 0.5. The upper limit of conditional formula (10) is more preferably 3, more preferably 2.5, more preferably 2.2, more preferably 2, and more preferably 1.5.

[0088] It is preferable that the zoom lens satisfies the following conditional expression (11). By making sure that the corresponding value of conditional expression (11) is not below the lower limit, the amount of movement during focusing can be reduced, which is advantageous for miniaturization and faster focusing. By making sure that the corresponding value of conditional expression (11) is not above the upper limit, the refractive power of the focusing group does not become too strong, which is advantageous for suppressing aberration fluctuations during focusing. 0.9 <ft / |ffoc|<20 (11)

[0089] In order to obtain better characteristics, it is more preferable that the lower limit of conditional formula (11) be 1, more preferably 1.1, even more preferably 1.2, even more preferably 1.3, and even more preferably 1.5. It is more preferable that the upper limit of conditional formula (11) be 15, more preferably 12, even more preferably 10, even more preferably 8, and even more preferably 6.

[0090] It is preferable that the zoom lens satisfies the following conditional expression (12). In this specification, the unit of ωw is degrees. By making sure that the corresponding value of conditional expression (12) is not equal to or smaller than the lower limit, it is advantageous for achieving a wide angle. By making sure that the corresponding value of conditional expression (12) is not equal to or larger than the upper limit, it is advantageous for achieving a compact size. 10<ωw<55 (12)

[0091] In order to obtain better characteristics, it is more preferable that the lower limit of conditional formula (12) be 12, even more preferably 15, even more preferably 20, even more preferably 25, and even more preferably 30. It is more preferable that the upper limit of conditional formula (12) be 50, even more preferably 48, even more preferably 46, even more preferably 44, and even more preferably 42.

[0092] It is preferable that the zoom lens satisfies the following conditional expression (13). Here, the focal length of the object-side negative group GN when focused on an object at infinity at the wide-angle end is fGNw. By making sure that the corresponding value of conditional expression (13) is not equal to or less than the lower limit, the refractive power of the object-side negative group GN does not become too strong, which is advantageous for suppressing aberration fluctuations during zooming. By making sure that the corresponding value of conditional expression (13) is not equal to or more than the upper limit, the refractive power of the object-side negative group GN does not become too weak, which can suppress the amount of movement of the object-side negative group GN during zooming, which is advantageous for miniaturization in the optical axis direction. -4.5 <fw / fGNw<-0.3 (13)

[0093] In order to obtain better characteristics, the lower limit of conditional formula (13) is more preferably set to -4, more preferably -3.5, even more preferably -3.2, even more preferably -3, even more preferably -2.5, and even more preferably -2. The upper limit of conditional formula (13) is more preferably set to -0.5, more preferably -0.7, even more preferably -0.9, even more preferably -1, even more preferably -1.1, and even more preferably -1.2.

[0094] It is preferable that the zoom lens satisfies the following conditional expression (14). By making sure that the corresponding value of conditional expression (14) is not equal to or less than the lower limit, the refractive power of the object-side negative group GN does not become too strong, which is advantageous for suppressing aberration fluctuations during zooming. By making sure that the corresponding value of conditional expression (14) is not equal to or more than the upper limit, the refractive power of the object-side negative group GN does not become too weak, which makes it possible to suppress the amount of movement of the object-side negative group GN during zooming, which is advantageous for miniaturization in the optical axis direction. -twenty one <ft / fGNw<-2.5 (14)

[0095] In order to obtain better characteristics, it is more preferable that the lower limit of conditional formula (14) be set to -18, more preferably -16, even more preferably -14, even more preferably -12, even more preferably -9, and even more preferably -6. It is more preferable that the upper limit of conditional formula (14) be set to -3, more preferably -3.5, and even more preferably -4.

[0096] It is preferable that the zoom lens satisfies the following conditional expression (15). Here, the focal length of the middle group GM at the telephoto end is fGMt. By ensuring that the corresponding value of conditional expression (15) is not below the lower limit, the diameter of the light beam entering the final group GE can be suppressed, which is advantageous for making the diameter smaller. By ensuring that the corresponding value of conditional expression (15) is not above the upper limit, which is advantageous for suppressing aberration fluctuations during magnification. 0.5 <ft / fGMt<15 (15)

[0097] In order to obtain better characteristics, the lower limit of conditional formula (15) should more preferably be 0.8, more preferably be 1, more preferably be 1.2, more preferably be 2, more preferably be 2.5, and more preferably be 3. The upper limit of conditional formula (15) should more preferably be 13, more preferably be 12, more preferably be 10, more preferably be 9, more preferably be 7, and more preferably be 6.5.

[0098] It is preferable that the zoom lens satisfies the following conditional expression (16). Here, TLt is the sum of the distance on the optical axis from the lens surface closest to the object side of the object side positive group GP to the lens surface closest to the image side of the final group GE when focused on an object at infinity at the telephoto end, and the back focus in the air equivalent distance of the entire system. TLw is the sum of the distance on the optical axis from the lens surface closest to the object side of the object side positive group GP to the lens surface closest to the image side of the final group GE when focused on an object at infinity at the wide-angle end, and the back focus in the air equivalent distance of the entire system. By making the corresponding value of conditional expression (16) not equal to or less than the lower limit, the lens group closest to the object side can be moved a significant amount during zooming, which is advantageous for suppressing aberration fluctuations during zooming. By making the corresponding value of conditional expression (16) not equal to or more than the upper limit, the change in the overall length during zooming can be reduced, which is advantageous for miniaturization. 0.05<(TLt-TLw) / fw×(fw / ft)<1.5 (16)

[0099] In order to obtain better characteristics, the lower limit of conditional formula (16) is more preferably 0.07, more preferably 0.08, more preferably 0.09, more preferably 0.12, and more preferably 0.15. The upper limit of conditional formula (16) is more preferably 1, more preferably 0.8, more preferably 0.6, more preferably 0.55, and more preferably 0.35.

[0100] It is preferable that the zoom lens satisfies the following conditional expression (17). Here, the lateral magnification of the first focusing group when focused on an object at infinity at the wide-angle end is βfw. The combined lateral magnification of all lenses on the image side of the first focusing group when focused on an object at infinity at the wide-angle end is βfRw. If there is no lens on the image side of the first focusing group, βfRw=1. By ensuring that the corresponding value of conditional expression (17) is not equal to or less than the lower limit, the amount of movement of the focusing group during focusing can be reduced, which is advantageous for making the entire zoom lens compact. By ensuring that the corresponding value of conditional expression (17) is not equal to or more than the upper limit, which is advantageous for suppressing aberration fluctuations during focusing. 0.15<|(1-βfw 2 )×βfRw 2 |<9 (17)

[0101] In order to obtain better characteristics, the lower limit of conditional formula (17) is more preferably 0.16, more preferably 0.18, more preferably 0.2, more preferably 0.25, more preferably 0.5, more preferably 0.8, and more preferably 1.1. The upper limit of conditional formula (17) is more preferably 7, more preferably 4.9, more preferably 4, more preferably 3, more preferably 2.5, more preferably 2, and more preferably 1.8.

[0102] It is preferable that the zoom lens satisfies the following conditional expression (18). Here, the lateral magnification of the first focusing group when focused on an object at infinity at the telephoto end is βft. The combined lateral magnification of all lenses on the image side of the first focusing group when focused on an object at infinity at the telephoto end is βfRt. Note that if there is no lens on the image side of the first focusing group, βfRt=1. By ensuring that the corresponding value of conditional expression (18) is not equal to or less than the lower limit, the amount of movement of the focusing group during focusing can be reduced, which is advantageous for making the entire zoom lens smaller. By ensuring that the corresponding value of conditional expression (18) is not equal to or more than the upper limit, which is advantageous for suppressing aberration fluctuations during focusing. 0.8<|(1-βft 2 )×βfRt 2 |<23 (18)

[0103] In order to obtain better characteristics, it is more preferable that the lower limit of conditional formula (18) be 1, more preferably 1.1, even more preferably 1.2, even more preferably 1.5, even more preferably 2, even more preferably 3, and even more preferably 4.5. It is more preferable that the upper limit of conditional formula (18) be 18, more preferably 15, even more preferably 12, even more preferably 10, even more preferably 9, even more preferably 8, and even more preferably 7.

[0104] It is preferable that the zoom lens, in a configuration including an aperture stop St, satisfies the following conditional expression (19). Here, STw is the open aperture diameter of the aperture stop St when focused on an object at infinity at the wide-angle end. STt is the open aperture diameter of the aperture stop St when focused on an object at infinity at the telephoto end. The open aperture diameter is the diameter of the opening of the aperture stop St in the open state. If the opening is polygonal, the open aperture diameter is the diameter of the circumscribed circle of the polygon in the open state. By making the corresponding value of conditional expression (19) equal to or greater than the lower limit, the difference in the open aperture diameter between the wide-angle end and the telephoto end does not become too large, which is advantageous for miniaturizing the aperture unit. By making the corresponding value of conditional expression (19) equal to or greater than the upper limit, it is easy to reduce the change in F-number between the wide-angle end and the telephoto end. 0.55 <STw / STt<1 (19)

[0105] In order to obtain better characteristics, the lower limit of conditional formula (19) is more preferably 0.6, more preferably 0.65, more preferably 0.7, more preferably 0.73, more preferably 0.74, and more preferably 0.75. The upper limit of conditional formula (19) is more preferably 0.99, more preferably 0.98, more preferably 0.97, more preferably 0.96, more preferably 0.92, and more preferably 0.86.

[0106] It is preferable for the zoom lens to satisfy the following conditional expression (20). Here, the average of the Abbe numbers based on the d-line of all the positive lenses in the object-side positive group GP is taken as νPave. Making sure that the corresponding value of conditional expression (20) does not become equal to or smaller than the lower limit is advantageous for suppressing longitudinal chromatic aberration. Making sure that the corresponding value of conditional expression (20) does not become equal to or larger than the upper limit increases the availability of materials, allowing the use of materials that are easier to manufacture. 50<νPave<115 (20)

[0107] In order to obtain better characteristics, it is more preferable that the lower limit of conditional formula (20) be 52, even more preferably 53, even more preferably 55, even more preferably 59, even more preferably 62, and even more preferably 75. It is more preferable that the upper limit of conditional formula (20) be 110, even more preferably 105, even more preferably 100, even more preferably 98, even more preferably 95, and even more preferably 90.

[0108] It is preferable that the zoom lens satisfies the following conditional expression (21). Here, the axial thickness of the object-side positive group GP at the wide-angle end is defined as DGPw. The "axial thickness" of a group refers to the axial distance from the lens surface of the group closest to the object to the lens surface of the group closest to the image. As an example, FIG. 2 shows the thickness DGPw. By ensuring that the corresponding value of conditional expression (21) is not equal to or less than the lower limit, it is advantageous for suppressing axial chromatic aberration. By ensuring that the corresponding value of conditional expression (21) is not equal to or more than the upper limit, it is advantageous for making the entire zoom lens smaller and lighter. 0.04 <DGPw / TLw<0.25 (21)

[0109] In order to obtain better characteristics, the lower limit of condition (21) should more preferably be 0.05, even more preferably be 0.06, and even more preferably be 0.08.The upper limit of condition (21) should more preferably be 0.2, even more preferably be 0.18, and even more preferably be 0.15.

[0110] It is preferable that the zoom lens satisfies the following conditional expression (22). Here, the thickness on the optical axis of the object-side negative group GN when focused on an object at infinity at the wide-angle end is designated as DGNw. As an example, the above thickness DGNw is shown in FIG. 2. Ensuring that the corresponding value of conditional expression (22) is not equal to or less than the lower limit is advantageous for suppressing aberration fluctuations during zooming. Ensuring that the corresponding value of conditional expression (22) is not equal to or greater than the upper limit is advantageous for reducing the size and weight of the entire zoom lens. 0.01 <DGNw / TLw<0.35 (22)

[0111] In order to obtain better characteristics, the lower limit of conditional formula (22) is more preferably 0.03, more preferably 0.05, more preferably 0.07, more preferably 0.08, more preferably 0.09, and more preferably 0.1. The upper limit of conditional formula (22) is more preferably 0.3, more preferably 0.25, more preferably 0.2, more preferably 0.16, more preferably 0.13, and more preferably 0.11.

[0112] It is preferable for the zoom lens to satisfy the following conditional expression (23). Here, the axial thickness of the middle group GM at the wide-angle end is designated as DGMw. As an example, the above thickness DGMw is shown in FIG. 2. Ensuring that the corresponding value of conditional expression (23) is not equal to or less than the lower limit thereof is advantageous for suppressing aberration fluctuations during zooming. Ensuring that the corresponding value of conditional expression (23) is not equal to or greater than the upper limit thereof is advantageous for making the entire zoom lens smaller and lighter. 0.03 <DGMw / TLw<0.45 (23)

[0113] In order to obtain better characteristics, the lower limit of conditional formula (23) is more preferably 0.05, more preferably 0.07, more preferably 0.09, more preferably 0.1, more preferably 0.13, more preferably 0.15, and more preferably 0.16. The upper limit of conditional formula (23) is more preferably 0.4, more preferably 0.38, more preferably 0.36, more preferably 0.34, more preferably 0.32, more preferably 0.3, and more preferably 0.28.

[0114] It is preferable for the zoom lens to satisfy the following conditional expression (24). Here, the thickness on the optical axis of the final group GE when focused on an object at infinity at the wide-angle end is designated as DGEw. As an example, the above thickness DGEw is shown in FIG. 2. Ensuring that the corresponding value of conditional expression (24) is not equal to or less than the lower limit thereof is advantageous for suppressing fluctuations in astigmatism during magnification. Ensuring that the corresponding value of conditional expression (24) is not equal to or greater than the upper limit thereof is advantageous for making the entire zoom lens smaller and lighter. 0.015 <DGEw / TLw<0.4 (24)

[0115] In order to obtain better characteristics, the lower limit of conditional formula (24) is more preferably 0.016, more preferably 0.018, more preferably 0.025, more preferably 0.04, more preferably 0.06, more preferably 0.08, and more preferably 0.11. The upper limit of conditional formula (24) is more preferably 0.35, more preferably 0.3, more preferably 0.26, more preferably 0.24, more preferably 0.22, more preferably 0.2, and more preferably 0.19.

[0116] It is preferable for the zoom lens to satisfy the following conditional expression (25). Here, the axial thickness of the middle group GM at the telephoto end is designated as DGMt. As an example, the above thickness DGMt is shown in FIG. 2. Ensuring that the corresponding value of conditional expression (25) is not equal to or less than the lower limit thereof is advantageous for suppressing aberration fluctuations during zooming. Ensuring that the corresponding value of conditional expression (25) is not equal to or greater than the upper limit thereof is advantageous for making the entire zoom lens smaller and lighter. 0.02 <DGMt / TLt<0.35 (25)

[0117] In order to obtain better characteristics, the lower limit of conditional formula (25) is more preferably 0.04, more preferably 0.06, more preferably 0.08, more preferably 0.1, more preferably 0.12, more preferably 0.13, and more preferably 0.14. The upper limit of conditional formula (25) is more preferably 0.3, more preferably 0.28, more preferably 0.26, more preferably 0.24, more preferably 0.22, more preferably 0.2, and more preferably 0.19.

[0118] It is preferable that the zoom lens satisfies the following conditional expression (26). Here, the displacement amount of the position on the optical axis of the lens surface closest to the object of the object-side positive group GP during zooming from the wide-angle end to the telephoto end is ΔGP. As an example, FIG. 2 shows the above displacement amount ΔGP. The sign of ΔGP is negative when the lens surface closest to the object of the object-side positive group GP moves toward the object side during zooming from the wide-angle end to the telephoto end, and positive when it moves toward the image side. By making sure that the corresponding value of conditional expression (26) is not equal to or less than the lower limit, it is advantageous for suppressing aberration fluctuations during zooming. By making sure that the corresponding value of conditional expression (26) is not equal to or more than the upper limit, it is advantageous for reducing the size and weight of the entire zoom lens. -0.6<ΔGP / TLt<-0.04 (26)

[0119] In order to obtain better characteristics, the lower limit of conditional formula (26) is more preferably -0.55, more preferably -0.52, more preferably -0.5, more preferably -0.45, more preferably -0.43, and more preferably -0.4. The upper limit of conditional formula (26) is more preferably -0.05, more preferably -0.07, more preferably -0.1, more preferably -0.15, more preferably -0.2, and more preferably -0.25.

[0120] It is preferable that the zoom lens satisfies the following conditional expression (27). Here, ΔGN is the amount of displacement of the position on the optical axis of the lens surface closest to the object in the object-side negative group GN when zooming from the wide-angle end to the telephoto end with the focus on an object at infinity. As an example, FIG. 2 shows the above-mentioned amount of displacement ΔGN. By ensuring that the corresponding value of conditional expression (27) is not equal to or less than the lower limit, it is advantageous for suppressing aberration fluctuations when zooming, and is also advantageous for achieving a high zoom ratio. By ensuring that the corresponding value of conditional expression (27) is not equal to or more than the upper limit, it is advantageous for reducing the size of the entire zoom lens. 0.002<|ΔGN| / TLt<0.35 (27)

[0121] In order to obtain better characteristics, the lower limit of conditional formula (27) is more preferably 0.003, more preferably 0.004, more preferably 0.005, more preferably 0.006, more preferably 0.007, and more preferably 0.008. The upper limit of conditional formula (27) is more preferably 0.3, more preferably 0.25, more preferably 0.23, more preferably 0.2, more preferably 0.19, and more preferably 0.18.

[0122] It is preferable that the zoom lens satisfies the following conditional expression (28). Here, the amount of displacement of the on-optical axis position of the lens surface of the middle group GM closest to the object when changing magnification from the wide-angle end to the telephoto end is designated as ΔGM. As an example, FIG. 2 shows the above-mentioned amount of displacement ΔGM. Ensuring that the corresponding value of conditional expression (28) is not equal to or less than the lower limit value is advantageous for suppressing aberration fluctuations when changing magnification. Ensuring that the corresponding value of conditional expression (28) is not equal to or greater than the upper limit value is advantageous for making the entire zoom lens more compact. 0.001<|ΔGM| / TLt<0.4 (28)

[0123] In order to obtain better characteristics, the lower limit of conditional formula (28) should more preferably be 0.01, more preferably 0.015, more preferably 0.02, more preferably 0.04, more preferably 0.06, and more preferably 0.08. The upper limit of conditional formula (28) should more preferably be 0.35, more preferably 0.33, more preferably 0.31, more preferably 0.29, more preferably 0.27, and more preferably 0.25.

[0124] It is preferable that the zoom lens satisfies the following conditional expression (29). By making sure that the corresponding value of conditional expression (29) is not equal to or smaller than the lower limit, it is advantageous for achieving a high zoom ratio. By making sure that the corresponding value of conditional expression (29) is not equal to or larger than the upper limit, it is advantageous for achieving a compact size. -15 <fGPw / fGNw<-1.8 (29)

[0125] In order to obtain better characteristics, it is more preferable that the lower limit of condition (29) be set to -10, even more preferably to -8, even more preferably to -7.4, and even more preferably to -7. It is more preferable that the upper limit of condition (29) be set to -2, even more preferably to -2.5, even more preferably to -3, and even more preferably to -3.6.

[0126] It is preferable that the zoom lens satisfies the following conditional expression (30). By making sure that the corresponding value of conditional expression (30) is not equal to or less than the lower limit, it is advantageous to suppress aberration fluctuations on the telephoto side when changing magnification. By making sure that the corresponding value of conditional expression (30) is not equal to or greater than the upper limit, it is advantageous to suppress aberration fluctuations on the wide-angle side when changing magnification. 0.5 <fGMt / fGMw<3 (30)

[0127] In order to obtain better characteristics, it is more preferable that the lower limit of condition (30) be set to 0.6, even more preferably to 0.65, and even more preferably to 0.7. It is more preferable that the upper limit of condition (30) be set to 2, even more preferably to 1.5, and even more preferably to 1.1.

[0128] It is preferable that the zoom lens satisfies the following conditional expression (31). By making sure that the corresponding value of conditional expression (31) is not equal to or less than the lower limit, it is advantageous to reduce the amount of movement of the object-side negative group GN during zooming. By making sure that the corresponding value of conditional expression (31) is not equal to or greater than the upper limit, it is advantageous to effectively correct chromatic aberration of magnification at the wide-angle end. -3 <fGNw / fGMw<-0.1 (31)

[0129] In order to obtain better characteristics, the lower limit of conditional formula (31) is more preferably -2.5, more preferably -2, more preferably -1.7, more preferably -1.5, more preferably -1.2, more preferably -1, and more preferably -0.68. The upper limit of conditional formula (31) is more preferably -0.15, more preferably -0.2, more preferably -0.25, more preferably -0.3, more preferably -0.35, more preferably -0.4, and more preferably -0.45.

[0130] It is preferable that the zoom lens satisfies the following conditional expression (32). By making sure that the corresponding value of conditional expression (32) is not below the lower limit, the refractive power of the object-side positive group GP can be prevented from becoming too strong, which is particularly advantageous for good correction of spherical aberration and axial chromatic aberration at the telephoto end. By making sure that the corresponding value of conditional expression (32) is not above the upper limit, the refractive power of the object-side positive group GP can be prevented from becoming too weak, which can keep the amount of movement of the object-side positive group GP small when changing magnification, which is advantageous for making the lens system more compact. 0.15 <fGPw / |fGEw|<10 (32)

[0131] In order to obtain better characteristics, the lower limit of conditional formula (32) is more preferably 0.2, more preferably 0.25, more preferably 0.3, more preferably 0.35, more preferably 0.4, more preferably 0.45, and more preferably 0.5. The upper limit of conditional formula (32) is more preferably 9.5, more preferably 9, more preferably 8.5, more preferably 8, more preferably 7.5, more preferably 7, and more preferably 6.5.

[0132] It is preferable that the zoom lens satisfies the following conditional expression (33). By making sure that the corresponding value of conditional expression (33) is not equal to or less than the lower limit, it is advantageous for ensuring the back focus at the wide-angle end while realizing a high zoom ratio. By making sure that the corresponding value of conditional expression (33) is not equal to or greater than the upper limit, it is advantageous for shortening the overall length of the optical system since the image side principal point position can be moved closer to the object side. -2 <fGMw / fGEw<5 (33)

[0133] In order to obtain better characteristics, it is more preferable that the lower limit of conditional formula (33) be set to -1.5, even more preferably to -1, even more preferably to -0.5, even more preferably to 0, even more preferably to 0.5, and even more preferably to 1. It is more preferable that the upper limit of conditional formula (33) be set to 4, even more preferably to 3, even more preferably to 2.5, even more preferably to 2.2, even more preferably to 2, and even more preferably to 1.5.

[0134] It is preferable that the zoom lens satisfies the following conditional expression (34). Here, Denw is the distance on the optical axis from the lens surface closest to the object of the object-side positive group GP to the paraxial entrance pupil position Penw when focused on an object at infinity at the wide-angle end. As an example, FIG. 2 shows the above-mentioned paraxial entrance pupil position Penw and distance Denw. By making sure that the corresponding value of conditional expression (34) is not equal to or less than the lower limit, it is advantageous for suppressing aberration fluctuations during zooming. By making sure that the corresponding value of conditional expression (34) is not equal to or more than the upper limit, it is possible to suppress an increase in the diameter of the object-side positive group GP, which facilitates size reduction. 0.5 <Denw / fw<3 (34)

[0135] In order to obtain better characteristics, it is more preferable that the lower limit of conditional formula (34) be set to 0.65, even more preferably to 0.8, even more preferably to 0.9, even more preferably to 1, even more preferably to 1.2, and even more preferably to 1.4. It is more preferable that the upper limit of conditional formula (34) be set to 2.6, even more preferably to 2.2, even more preferably to 2, even more preferably to 1.8, even more preferably to 1.7, and even more preferably to 1.6.

[0136] It is preferable that the zoom lens satisfies the following conditional expression (35). Here, the distance on the optical axis from the paraxial exit pupil position Pexw to the image plane Sim in a state where an object at infinity is focused at the wide-angle end is defined as Dexw. However, when an optical member having no refractive power is disposed between the paraxial exit pupil position Pexw and the image plane Sim, the air-equivalent distance is used to calculate Dexw for the optical member. As an example, FIG. 2 shows the above-mentioned paraxial exit pupil position Pexw. By making the corresponding value of the conditional expression (35) not equal to or less than the lower limit, the angle of incidence of the off-axis chief ray on the image plane Sim can be reduced, which is advantageous for ensuring the amount of peripheral light. By making the corresponding value of the conditional expression (35) not equal to or more than the upper limit, the overall length of the optical system can be shortened, which is advantageous for miniaturization. 1.2 <Dexw / (fw×tanωw)<8 (35)

[0137] In order to obtain better characteristics, it is more preferable that the lower limit of conditional formula (35) be 1.5, more preferably 2, more preferably 2.3, more preferably 2.5, more preferably 2.8, and more preferably 3. It is more preferable that the upper limit of conditional formula (35) be 7, more preferably 6.8, more preferably 6.4, more preferably 5.5, more preferably 4.8, and more preferably 4.

[0138] It is preferable that the zoom lens satisfies the following conditional expression (36). Here, Fnot is the maximum F-number when focused on an object at infinity at the telephoto end. By ensuring that the corresponding value of conditional expression (36) is not equal to or less than the lower limit, it is advantageous to reduce the overall length while keeping the F-number small at the telephoto end. By ensuring that the corresponding value of conditional expression (36) is not equal to or greater than the upper limit, it is advantageous to suppress various aberrations over the entire zoom range. 1 <ft×Fnot / TLt<10.5 (36)

[0139] In order to obtain better characteristics, it is more preferable that the lower limit of conditional formula (36) be 1.2, even more preferably 1.4, even more preferably 1.6, even more preferably 1.8, and even more preferably 2. It is more preferable that the upper limit of conditional formula (36) be 8.6, even more preferably 6, even more preferably 5.5, even more preferably 5, even more preferably 4.7, even more preferably 4, even more preferably 3, and even more preferably 2.5.

[0140] The example shown in FIG. 1 is just one example, and various modifications are possible within the scope of the gist of the technology of the present disclosure. For example, the number of lens groups included in each of the object-side positive group GP, the object-side negative group GN, the intermediate group GM, and the final group GE may be different from that in the example of FIG. 1. Also, the number of lenses included in each lens group, the number of lenses included in the focusing group, and the number of lenses included in the vibration-proof group may be different from that in the example of FIG. 1. The lenses corresponding to the focusing group, the lenses corresponding to the vibration-proof group, the position of the aperture stop St, and the lens groups that move during magnification may be configured differently from that in the example of FIG. 1.

[0141] The object-side negative group GN may be configured to consist of two lens groups, which is advantageous in suppressing aberration fluctuations during magnification variation.

[0142] The intermediate group GM may be configured to consist of three lens groups, which is more advantageous in suppressing aberration fluctuations during magnification change than a configuration in which the intermediate group GM consists of two lens groups.

[0143] During focusing, the final group GE may be configured so that all or a part of it moves along the optical axis Z. This configuration is advantageous in suppressing breathing. Furthermore, when the focusing group is included in the final group GE in this way, the vibration reduction group may be configured so that it is included in the object-side negative group GN. By disposing the vibration reduction group within the object-side negative group GN, which has a relatively small outer diameter, the vibration reduction mechanism can also be made smaller, making it easier to make the entire lens device smaller.

[0144] The vibration reduction group may be configured to be the second lens group from the image side of the intermediate group GM, or the vibration reduction group may be configured to be only some of the lens groups included in the intermediate group GM.

[0145] The aperture stop St may be configured to be included in the final lens unit GE, which is advantageous for making the diameter of the final lens unit GE smaller.

[0146] During zooming, the lens group closest to the object side of the object-side positive group may be fixed relative to the image plane. In this case, the total length is constant during zooming, so that the fluctuation of the center of gravity during zooming can be reduced, thereby improving convenience during photography.

[0147] The lens unit closest to the image side of the final group GE may be configured to move during zooming, which is advantageous for suppressing aberration fluctuations during zooming.

[0148] The above-mentioned preferred and possible configurations can be arbitrarily combined within a range not causing any contradiction, and it is preferable that they are appropriately and selectively adopted according to the required specifications.

[0149] As an example, a preferred embodiment of the zoom lens of the present disclosure comprises, in order from the object side to the image side, an object-side positive group GP having positive refractive power, an object-side negative group GN having negative refractive power, an intermediate group GM, and a final group GE, wherein the object-side positive group GP, the object-side negative group GN, the intermediate group GM, and the final group GE each include at least one lens group, during magnification variation, all intervals between adjacent lens groups change while the mutual intervals of all lenses in each lens group remain constant, and during focusing, all lenses in the object-side positive group GP and all lenses in the intermediate group GM are fixed with respect to the image plane Sim, and the above conditional formula (1) is satisfied.

[0150] Next, an embodiment of the zoom lens of the present disclosure will be described with reference to the drawings. The reference symbols attached to each group in the cross-sectional view of each embodiment are used independently for each embodiment to avoid the explanation and the drawings becoming complicated due to the increase in the number of digits of the reference symbols. Therefore, even if the same reference symbols are attached in the drawings of different embodiments, they do not necessarily have the same configuration.

[0151] [Example 1] The configuration and movement locus of the zoom lens of the first embodiment are shown in FIG. 1, and the method of illustration and the configuration are as described above, so some overlapping explanations will be omitted here. The zoom lens of the first embodiment is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of two lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power and a second M lens group GM2 having negative refractive power. The final group GE is composed of one lens group having positive refractive power. The aperture stop St is included in the first M lens group GM1.

[0152] When changing magnification from the wide-angle end to the telephoto end, the final lens group GE is fixed with respect to the image plane Sim, and the other lens groups move while changing the spacing between them. The zoom lens includes only one focusing group. The focusing group is made up of the first to third lenses from the object side of the object-side negative group GN. When focusing from an object at infinity to a close object, the focusing group moves toward the image side. The vibration reduction group is made up of the second M lens group GM2.

[0153] For the zoom lens of Example 1, basic lens data is shown in Table 1, specifications and variable surface spacing is shown in Table 2, and aspheric coefficients are shown in Table 3.

[0154] The basic lens data table is written as follows. The Sn column shows the surface numbers, with the surface closest to the object being surface 1 and the numbers increasing by one as you move towards the image side. The R column shows the radius of curvature of each surface. The D column shows the surface spacing on the optical axis between each surface and its adjacent surface on the image side. The Nd column shows the refractive index for each lens with respect to the d-line. The νd column shows the Abbe number of each lens based on the d-line. The θgF column shows the partial dispersion ratio between the g-line and F-line of each lens.

[0155] If the refractive indices of a lens for the g-line, F-line, and C-line are Ng, NF, and NC, respectively, and the partial dispersion ratio of the lens between the g-line and F-line is θgF, then θgF is defined by the following equation. θgF=(Ng-NF) / (NF-NC)

[0156] The terms "d-line," "C-line," "F-line," and "g-line" used in this specification are emission lines, and the wavelength of the d-line is 587.56 nm (nanometers), the wavelength of the C-line is 656.27 nm (nanometers), the wavelength of the F-line is 486.13 nm (nanometers), and the wavelength of the g-line is 435.84 nm (nanometers).

[0157] In the basic lens data table, the sign of the radius of curvature of a surface with a convex shape facing the object side is positive, and the sign of the radius of curvature of a surface with a convex shape facing the image side is negative. Table 1 also shows the aperture stop St and optical member PP. In the column for the surface number of the surface corresponding to the aperture stop St, the surface number and the word (St) are entered. The value in the bottom row of the D column in the table is the distance between the surface in the table closest to the image side and the image plane Sim. The symbol DD[ ] is used to indicate the variable surface distance when varying magnification, and the surface number on the object side of this distance is entered in [ ] in the D column.

[0158] Table 2 shows the zoom ratio Zr, focal length f, back focal length Bf in air equivalent distance, maximum F-number FNo., maximum total angle of view 2ω, and variable surface spacing based on the d-line. The zoom ratio is synonymous with the zoom magnification. [°] in the 2ω column indicates that the unit is degrees. In Table 2, the columns labeled "Wide," "Middle," and "Tele" show the values ​​for the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively.

[0159] In the basic lens data, the surface numbers of aspheric surfaces are marked with an *, and the value of the paraxial radius of curvature is given in the column for the radius of curvature of the aspheric surface. In Table 3, the Sn row shows the surface numbers of the aspheric surfaces, and the KA and Am rows show the numerical values ​​of the aspheric coefficients for each aspheric surface. Note that m in Am is an integer of 3 or more, and differs depending on the surface. For example, for the 16th surface in Example 1, m = 4, 6, 8, 10, 12, 14, and 16. The numerical values ​​of the aspheric coefficients in Table 3, "E±n" (n: integer), are expressed as "×10 ±n " KA and Am are aspheric coefficients in the aspheric equation expressed below. Zd = C × h2 / {1+(1-KA×C 2 ×h 2 ) 1 / 2}+ΣAm×h m however, Zd: Aspheric depth (the length of the perpendicular line drawn from a point on the aspheric surface at height h to a plane perpendicular to the optical axis Z where the apex of the aspheric surface is in contact) h: Height (distance from optical axis Z to lens surface) C: Reciprocal of paraxial curvature radius KA, Am: Aspheric coefficients In the aspheric surface formula, Σ means the summation with respect to m.

[0160] In the data in each table, the angle unit is degrees and the length unit is millimeters, but since the optical system can be used with proportional enlargement or reduction, other appropriate units can be used. Also, in each table shown below, values ​​are rounded to a predetermined number of decimal places.

[0161] [Table 1]

[0162] [Table 2]

[0163] [Table 3]

[0164] FIG. 3 shows each aberration diagram of the zoom lens of Example 1 in a state where the lens is focused on an object at infinity. In FIG. 3, from the left, spherical aberration, astigmatism, distortion, and lateral chromatic aberration are shown. In FIG. 3, the upper row labeled "Wide" shows the aberration in the wide-angle end state, the middle row labeled "Middle" shows the aberration in the intermediate focal length state, and the lower row labeled "Tele" shows the aberration in the telephoto end state. In the spherical aberration diagram, the aberrations at the d-line, C-line, F-line, and g-line are shown by solid lines, long dashed lines, short dashed lines, and dashed dotted lines, respectively. In the astigmatism diagram, the aberration at the d-line in the sagittal direction is shown by solid lines, and the aberration at the d-line in the tangential direction is shown by short dashed lines. In the distortion diagram, the aberration at the d-line is shown by solid lines. In the lateral chromatic aberration diagram, the aberrations at the C-line, F-line, and g-line are shown by the long dashed line, short dashed line, and dashed dotted line, respectively. In the spherical aberration diagram, the maximum F-number is shown after FNo.=. In the other aberration diagrams, the maximum half angle of view is shown after ω=.

[0165] The symbols, meanings, description methods, and illustration methods of each piece of data related to the above-mentioned Example 1 are basically the same in the following Examples unless otherwise specified, so duplicated explanations will be omitted below.

[0166] [Example 2] The configuration and movement locus of the zoom lens of the second embodiment are shown in FIG. 4. The zoom lens of the second embodiment is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of two lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power and a second M lens group GM2 having negative refractive power. The final group GE is composed of one lens group having positive refractive power. An aperture stop St is included in the first M lens group GM1.

[0167] When changing magnification from the wide-angle end to the telephoto end, the final lens group GE is fixed with respect to the image plane Sim, and the other lens groups move while changing the spacing between them. The zoom lens includes only one focusing group. The focusing group is made up of the first to third lenses from the object side of the object-side negative group GN. When focusing from an object at infinity to a close object, the focusing group moves toward the image side. The vibration reduction group is made up of the second M lens group GM2.

[0168] For the zoom lens of Example 2, basic lens data is shown in Table 4, specifications and variable surface spacing in Table 5, aspheric coefficients in Table 6, and each aberration diagram is shown in FIG.

[0169] [Table 4]

[0170] [Table 5]

[0171] [Table 6]

[0172] [Example 3] The configuration and movement locus of the zoom lens of the third embodiment are shown in FIG. 6. The zoom lens of the third embodiment is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of two lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power and a second M lens group GM2 having negative refractive power. The final group GE is composed of one lens group having positive refractive power. An aperture stop St is included in the first M lens group GM1.

[0173] When changing magnification from the wide-angle end to the telephoto end, the final lens group GE is fixed with respect to the image plane Sim, and the other lens groups move while changing the spacing between them. The zoom lens includes only one focusing group. The focusing group is made up of the first and second two lenses from the image side of the object-side negative group GN. When focusing from an object at infinity to a close object, the focusing group moves toward the object side. The vibration reduction group is made up of the second M lens group GM2.

[0174] Regarding the zoom lens of Example 3, basic lens data is shown in Table 7, specifications and variable surface spacing in Table 8, aspheric coefficients in Table 9, and each aberration diagram is shown in FIG.

[0175] [Table 7]

[0176] [Table 8]

[0177] [Table 9]

[0178] [Example 4] The configuration and movement locus of the zoom lens of Example 4 are shown in FIG. 8. The zoom lens of Example 4 is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of two lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power and a second M lens group GM2 having negative refractive power. The final group GE is composed of one lens group having positive refractive power. An aperture stop St is included in the first M lens group GM1.

[0179] When changing magnification from the wide-angle end to the telephoto end, the final lens group GE is fixed with respect to the image plane Sim, and the other lens groups move while changing the spacing between them. The zoom lens includes only one focusing group. The focusing group is made up of a single lens that is closest to the image side of the object-side negative group GN. When focusing from an object at infinity to a close object, the focusing group moves toward the object side. The vibration reduction group is made up of the second M lens group GM2.

[0180] Regarding the zoom lens of Example 4, basic lens data is shown in Table 10, specifications and variable surface spacing in Table 11, aspheric coefficients in Table 12, and each aberration diagram is shown in FIG.

[0181] [Table 10]

[0182] [Table 11]

[0183] [Table 12]

[0184] [Example 5] The configuration and movement locus of the zoom lens of the fifth embodiment are shown in FIG. 10. The zoom lens of the fifth embodiment is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of two lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power and a second M lens group GM2 having negative refractive power. The final group GE is composed of one lens group having positive refractive power. An aperture stop St is included in the first M lens group GM1.

[0185] When changing magnification from the wide-angle end to the telephoto end, the final lens group GE is fixed with respect to the image plane Sim, and the other lens groups move while changing the spacing between them. The zoom lens includes only one focusing group. The focusing group is made up of a single lens that is closest to the image side of the object-side negative group GN. When focusing from an object at infinity to a close object, the focusing group moves toward the object side. The vibration reduction group is made up of the second M lens group GM2.

[0186] For the zoom lens of Example 5, basic lens data is shown in Table 13, specifications and variable surface spacing are shown in Table 14, aspheric coefficients are shown in Table 15, and each aberration diagram is shown in FIG.

[0187] [Table 13]

[0188] [Table 14]

[0189] [Table 15]

[0190] [Example 6] The configuration and movement locus of the zoom lens of Example 6 are shown in FIG. 12. The zoom lens of Example 6 is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of three lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power, a second M lens group GM2 having negative refractive power, and a third M lens group GM3 having positive refractive power. The final group GE is composed of one lens group having negative refractive power. An aperture stop St is included in the first M lens group GM1.

[0191] When changing magnification from the wide-angle end to the telephoto end, the final lens group GE is fixed with respect to the image plane Sim, and the other lens groups move while changing the spacing between them. The zoom lens includes only one focusing group. The focusing group is made up of a single lens that is closest to the image side of the object-side negative group GN. When focusing from an object at infinity to a close object, the focusing group moves toward the object side. The vibration reduction group is made up of the second M lens group GM2.

[0192] Regarding the zoom lens of Example 6, basic lens data is shown in Table 16, specifications and variable surface spacing in Table 17, aspheric coefficients in Table 18, and each aberration diagram is shown in FIG.

[0193] [Table 16]

[0194] [Table 17]

[0195] [Table 18]

[0196] [Example 7] The configuration and movement locus of the zoom lens of Example 7 are shown in FIG. 14. The zoom lens of Example 7 is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of two lens groups, in order from the object side to the image side, a 1N lens group GN1 having positive refractive power and a 2N lens group GN2 having negative refractive power. The intermediate group GM is composed of two lens groups, in order from the object side to the image side, a 1M lens group GM1 having positive refractive power and a 2M lens group GM2 having negative refractive power. The final group GE is composed of one lens group having positive refractive power. The aperture stop St is included in the 1M lens group GM1.

[0197] When changing magnification from the wide-angle end to the telephoto end, the final lens group GE is fixed with respect to the image plane Sim, and the other lens groups move while changing the spacing between them. The zoom lens includes only one focusing group. The focusing group consists of the first and second two lenses from the image side of the 2Nth lens group GN2. When focusing from an object at infinity to a close object, the focusing group moves toward the object side. The vibration reduction group consists of the 2Mth lens group GM2.

[0198] Regarding the zoom lens of Example 7, basic lens data is shown in Table 19, specifications and variable surface spacing in Table 20, aspheric coefficients in Table 21, and each aberration diagram is shown in FIG.

[0199] [Table 19]

[0200] [Table 20]

[0201] [Table 21]

[0202] [Example 8] The configuration and movement locus of the zoom lens of Example 8 are shown in FIG. 16. The zoom lens of Example 8 is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of two lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power and a second M lens group GM2 having positive refractive power. The final group GE is composed of one lens group having positive refractive power. An aperture stop St is included in the first M lens group GM1.

[0203] When changing magnification from the wide-angle end to the telephoto end, the final lens group GE is fixed with respect to the image plane Sim, and the other lens groups move while changing the spacing between them. The zoom lens includes only one focusing group. The focusing group consists of a single lens that is closest to the image in the object-side negative group GN. When focusing from an object at infinity to a close object, the focusing group moves toward the object side. The vibration reduction group consists of the first and second lenses from the image side of the firstM lens group GM1.

[0204] Regarding the zoom lens of Example 8, basic lens data is shown in Table 22, specifications and variable surface spacing in Table 23, aspheric coefficients in Table 24, and each aberration diagram is shown in FIG.

[0205] [Table 22]

[0206] [Table 23]

[0207] [Table 24]

[0208] [Example 9] The configuration and movement locus of the zoom lens of Example 9 are shown in FIG. 18. The zoom lens of Example 9 is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of two lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power and a second M lens group GM2 having positive refractive power. The final group GE is composed of one lens group having positive refractive power. An aperture stop St is included in the first M lens group GM1.

[0209] When varying magnification from the wide-angle end to the telephoto end, the final lens group GE is fixed with respect to the image plane Sim, and the other lens groups move while changing the spacing between adjacent lens groups. The zoom lens includes only one focusing group. The focusing group is made up of the object-side negative group GN. When focusing from an object at infinity to a close object, the focusing group moves toward the object side. The vibration reduction group is made up of the first and second two lenses from the image side of the 1stM lens group GM1.

[0210] Regarding the zoom lens of Example 9, basic lens data is shown in Table 25, specifications and variable surface spacing in Table 26, aspheric coefficients in Table 27, and each aberration diagram is shown in FIG.

[0211] [Table 25]

[0212] [Table 26]

[0213] [Table 27]

[0214] [Example 10] The configuration and movement locus of the zoom lens of Example 10 are shown in FIG. 20. The zoom lens of Example 10 is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of two lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power and a second M lens group GM2 having negative refractive power. The final group GE is composed of one lens group having positive refractive power. An aperture stop St is included in the first M lens group GM1.

[0215] When changing magnification from the wide-angle end to the telephoto end, all lens groups move while changing the spacing between adjacent lens groups. The zoom lens includes only one focusing group. The focusing group consists of a single lens in the final group GE that is closest to the object. When focusing from an object at infinity to a close object, the focusing group moves toward the object. The image stabilization group consists of the second M lens group GM2.

[0216] Regarding the zoom lens of Example 10, basic lens data is shown in Table 28, specifications and variable surface spacing in Table 29, aspheric coefficients in Table 30, and each aberration diagram is shown in FIG.

[0217] [Table 28]

[0218] [Table 29]

[0219] [Table 30]

[0220] [Example 11] The configuration and movement locus of the zoom lens of Example 11 are shown in FIG. 22. The zoom lens of Example 11 is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of three lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power, a second M lens group GM2 having negative refractive power, and a third M lens group GM3 having positive refractive power. The final group GE is composed of one lens group having negative refractive power. An aperture stop St is included in the first M lens group GM1.

[0221] When changing magnification from the wide-angle end to the telephoto end, all lens groups move while changing the spacing between adjacent lens groups. The zoom lens includes only one focusing group. The focusing group consists of a single lens in the final group GE that is closest to the object. When focusing from an object at infinity to a close object, the focusing group moves toward the image side. The image stabilization group consists of the second M lens group GM2.

[0222] Concerning the zoom lens of Example 11, basic lens data is shown in Table 31, specifications and variable surface spacing in Table 32, aspheric coefficients in Table 33, and each aberration diagram is shown in FIG.

[0223] [Table 31]

[0224] [Table 32]

[0225] [Table 33]

[0226] [Example 12] The configuration and movement locus of the zoom lens of Example 12 are shown in FIG. 24. The zoom lens of Example 12 is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of two lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power and a second M lens group GM2 having negative refractive power. The final group GE is composed of one lens group having positive refractive power. An aperture stop St is included in the first M lens group GM1.

[0227] When changing magnification from the wide-angle end to the telephoto end, all lens groups move while changing the spacing between adjacent lens groups. The zoom lens includes only one focusing group. The focusing group consists of a single lens that is the second from the object side of the final group GE. When focusing from an object at infinity to a close object, the focusing group moves toward the image side. The vibration reduction group consists of the second M lens group GM2.

[0228] Concerning the zoom lens of Example 12, basic lens data is shown in Table 34, the specifications and variable surface spacing are shown in Table 35, the aspheric coefficients are shown in Table 36, and each aberration diagram is shown in FIG.

[0229] [Table 34]

[0230] [Table 35]

[0231] [Table 36]

[0232] [Example 13] The configuration and movement locus of the zoom lens of Example 13 are shown in FIG. 26. The zoom lens of Example 13 is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of two lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power and a second M lens group GM2 having negative refractive power. The final group GE is composed of one lens group having positive refractive power. An aperture stop St is included in the first M lens group GM1.

[0233] When changing magnification from the wide-angle end to the telephoto end, all lens groups move while changing the spacing between adjacent lens groups. The zoom lens includes only one focusing group. The focusing group consists of a single lens that is the second from the object side of the final group GE. When focusing from an object at infinity to a close object, the focusing group moves toward the image side. The vibration reduction group consists of the second M lens group GM2.

[0234] Regarding the zoom lens of Example 13, basic lens data is shown in Table 37, specifications and variable surface spacing in Table 38, aspheric coefficients in Table 39, and each aberration diagram is shown in FIG.

[0235] [Table 37]

[0236] [Table 38]

[0237] [Table 39]

[0238] [Example 14] The configuration and movement locus of the zoom lens of Example 14 are shown in FIG. 28. The zoom lens of Example 14 is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of two lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power and a second M lens group GM2 having negative refractive power. The final group GE is composed of one lens group having positive refractive power. An aperture stop St is included in the first M lens group GM1.

[0239] When changing magnification from the wide-angle end to the telephoto end, all lens groups move while changing the spacing between adjacent lens groups. The zoom lens includes only one focusing group. The focusing group consists of a single lens that is the second from the object side of the final group GE. When focusing from an object at infinity to a close object, the focusing group moves toward the image side. The vibration reduction group consists of the second M lens group GM2.

[0240] Concerning the zoom lens of Example 14, basic lens data is shown in Table 40, specifications and variable surface spacing in Table 41, aspheric coefficients in Table 42, and each aberration diagram is shown in FIG.

[0241] [Table 40]

[0242] [Table 41]

[0243] [Table 42]

[0244] [Example 15] The configuration and movement locus of the zoom lens of Example 15 are shown in FIG. 30. The zoom lens of Example 15 is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of two lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power and a second M lens group GM2 having negative refractive power. The final group GE is composed of one lens group having positive refractive power. An aperture stop St is included in the first M lens group GM1.

[0245] When changing magnification from the wide-angle end to the telephoto end, the object-side negative group GN is fixed with respect to the image plane Sim, and the other lens groups move while changing the spacing between adjacent lens groups. The zoom lens includes only one focusing group. The focusing group is made up of a single lens that is the second from the object side of the final group GE. When focusing from an object at infinity to a close object, the focusing group moves toward the image side. The vibration reduction group is made up of the second M lens group GM2.

[0246] Concerning the zoom lens of Example 15, basic lens data is shown in Table 43, specifications and variable surface spacing in Table 44, aspheric coefficients in Table 45, and each aberration diagram is shown in FIG.

[0247] [Table 43]

[0248] [Table 44]

[0249] [Table 45]

[0250] [Example 16] The configuration and movement locus of the zoom lens of Example 16 are shown in FIG. 32. The zoom lens of Example 16 is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of two lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power and a second M lens group GM2 having negative refractive power. The final group GE is composed of one lens group having positive refractive power. An aperture stop St is included in the first M lens group GM1.

[0251] When changing magnification from the wide-angle end to the telephoto end, all lens groups move while changing the spacing between adjacent lens groups. A zoom lens includes only one focusing group. The focusing group consists of a single lens that is the second from the object side of the final group GE. When focusing from an object at infinity to a close object, the focusing group moves toward the object side. The vibration reduction group consists of the second M lens group GM2.

[0252] Concerning the zoom lens of Example 16, basic lens data is shown in Table 46, the specifications and variable surface spacing are shown in Table 47, the aspheric coefficients are shown in Table 48, and each aberration diagram is shown in FIG.

[0253] [Table 46]

[0254] [Table 47]

[0255] [Table 48]

[0256] [Example 17] The configuration and movement locus of the zoom lens of Example 17 are shown in FIG. 34. The zoom lens of Example 17 is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of two lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power and a second M lens group GM2 having negative refractive power. The final group GE is composed of one lens group having positive refractive power. An aperture stop St is included in the first M lens group GM1.

[0257] When changing magnification from the wide-angle end to the telephoto end, all lens groups move while changing the spacing between adjacent lens groups. The zoom lens includes only one focusing group. The focusing group consists of a single lens in the final group GE that is closest to the image. When focusing from an object at infinity to a close object, the focusing group moves toward the image side. The image stabilization group consists of the second M lens group GM2.

[0258] Concerning the zoom lens of Example 17, basic lens data is shown in Table 49, the specifications and variable surface spacing are shown in Table 50, the aspheric coefficients are shown in Table 51, and each aberration diagram is shown in FIG.

[0259] [Table 49]

[0260] [Table 50]

[0261] [Table 51]

[0262] [Example 18] The configuration and movement locus of the zoom lens of Example 18 are shown in FIG. 36. The zoom lens of Example 18 is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of two lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power and a second M lens group GM2 having negative refractive power. The final group GE is composed of one lens group having positive refractive power. An aperture stop St is included in the final group GE.

[0263] When changing magnification from the wide-angle end to the telephoto end, the object-side positive group GP and the final group GE are fixed with respect to the image plane Sim, and the other lens groups move while changing the spacing between adjacent lens groups. A zoom lens contains only one focusing group. The focusing group consists of two lenses, the fourth and fifth from the object side of the final group GE. When focusing from an object at infinity to a close object, the focusing group moves toward the image side. The vibration reduction group consists of three lenses, the second to fourth from the object side of the object-side negative group GN.

[0264] Concerning the zoom lens of Example 18, basic lens data is shown in Table 52, specifications and variable surface spacing are shown in Table 53, aspheric coefficients are shown in Table 54, and each aberration diagram is shown in FIG.

[0265] [Table 52]

[0266] [Table 53]

[0267] [Table 54]

[0268] [Example 19] The configuration and movement locus of the zoom lens of Example 19 are shown in FIG. 38. The zoom lens of Example 19 is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of two lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power and a second M lens group GM2 having negative refractive power. The final group GE is composed of one lens group having positive refractive power. An aperture stop St is included in the final group GE.

[0269] When changing magnification from the wide-angle end to the telephoto end, the object-side positive group GP and the final group GE are fixed with respect to the image plane Sim, and the other lens groups move while changing the spacing between adjacent lens groups. A zoom lens contains only one focusing group. The focusing group consists of two lenses, the fourth and fifth from the object side of the final group GE. When focusing from an object at infinity to a close object, the focusing group moves toward the image side. The vibration reduction group consists of three lenses, the second to fourth from the object side of the object-side negative group GN.

[0270] Concerning the zoom lens of Example 19, basic lens data is shown in Table 55, the specifications and variable surface spacing are shown in Table 56, the aspheric coefficients are shown in Table 57, and each aberration diagram is shown in FIG.

[0271] [Table 55]

[0272] [Table 56]

[0273] [Table 57]

[0274] [Example 20] The configuration and movement locus of the zoom lens of Example 20 are shown in FIG. 40. The zoom lens of Example 20 is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of two lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power and a second M lens group GM2 having negative refractive power. The final group GE is composed of one lens group having positive refractive power. An aperture stop St is included in the final group GE.

[0275] When changing magnification from the wide-angle end to the telephoto end, the object-side positive group GP and the final group GE are fixed with respect to the image plane Sim, and the other lens groups move while changing the spacing between adjacent lens groups. A zoom lens contains only one focusing group. The focusing group consists of two lenses, the fourth and fifth from the object side of the final group GE. When focusing from an object at infinity to a close object, the focusing group moves toward the image side. The vibration reduction group consists of three lenses, the second to fourth from the object side of the object-side negative group GN.

[0276] Concerning the zoom lens of Example 20, basic lens data is shown in Table 58, the specifications and variable surface spacing are shown in Table 59, the aspheric coefficients are shown in Table 60, and each aberration diagram is shown in FIG.

[0277] [Table 58]

[0278] [Table 59]

[0279] [Table 60]

[0280] [Example 21] The configuration and movement locus of the zoom lens of Example 21 are shown in FIG. 42. The zoom lens of Example 21 is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of two lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power and a second M lens group GM2 having negative refractive power. The final group GE is composed of one lens group having positive refractive power. An aperture stop St is included in the final group GE.

[0281] When changing magnification from the wide-angle end to the telephoto end, the object-side positive group GP and the final group GE are fixed with respect to the image plane Sim, and the other lens groups move while changing the spacing between adjacent lens groups. A zoom lens includes only one focusing group. The focusing group consists of three lenses that are the fifth to seventh from the object side of the final group GE. When focusing from an object at infinity to a close object, the focusing group moves toward the object side. The image stabilization group consists of three lenses that are the second to fourth from the object side of the object-side negative group GN.

[0282] Concerning the zoom lens of Example 21, basic lens data is shown in Table 61, the specifications and variable surface spacing are shown in Table 62, the aspheric coefficients are shown in Table 63, and each aberration diagram is shown in FIG.

[0283] [Table 61]

[0284] [Table 62]

[0285] [Table 63]

[0286] [Example 22] The configuration and movement locus of the zoom lens of Example 22 are shown in FIG. 44. The zoom lens of Example 22 is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of two lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power and a second M lens group GM2 having negative refractive power. The final group GE is composed of one lens group having positive refractive power. An aperture stop St is included in the final group GE.

[0287] When changing magnification from the wide-angle end to the telephoto end, the object-side positive group GP and the final group GE are fixed with respect to the image plane Sim, and the other lens groups move while changing the spacing between adjacent lens groups. A zoom lens includes only one focusing group. The focusing group consists of three lenses that are the fourth to sixth from the object side of the final group GE. When focusing from an object at infinity to a close object, the focusing group moves toward the object side. The image stabilization group consists of three lenses that are the second to fourth from the object side of the object-side negative group GN.

[0288] Regarding the zoom lens of Example 22, the basic lens data is shown in Table 64, the specifications and variable surface spacing are shown in Table 65, the aspheric coefficients are shown in Table 66, and each aberration diagram is shown in FIG.

[0289] [Table 64]

[0290] [Table 65]

[0291] [Table 66]

[0292] [Example 23] The configuration and movement locus of the zoom lens of Example 23 are shown in FIG. 46. The zoom lens of Example 23 is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of two lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power and a second M lens group GM2 having negative refractive power. The final group GE is composed of one lens group having positive refractive power. An aperture stop St is included in the final group GE.

[0293] When changing magnification from the wide-angle end to the telephoto end, the object-side positive group GP and the final group GE are fixed with respect to the image plane Sim, and the other lens groups move while changing the spacing between adjacent lens groups. A zoom lens includes only one focusing group. The focusing group consists of three lenses that are the fifth to seventh from the object side of the final group GE. When focusing from an object at infinity to a close object, the focusing group moves toward the object side. The image stabilization group consists of three lenses that are the second to fourth from the object side of the object-side negative group GN.

[0294] Concerning the zoom lens of Example 23, basic lens data is shown in Table 67, the specifications and variable surface spacing are shown in Table 68, the aspheric coefficients are shown in Table 69, and each aberration diagram is shown in FIG.

[0295] [Table 67]

[0296] [Table 68]

[0297] [Table 69]

[0298] [Example 24] The configuration and movement locus of the zoom lens of Example 24 are shown in FIG. 48. The zoom lens of Example 24 is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of two lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power and a second M lens group GM2 having negative refractive power. The final group GE is composed of one lens group having positive refractive power. An aperture stop St is included in the final group GE.

[0299] When changing magnification from the wide-angle end to the telephoto end, the object-side positive group GP and the final group GE are fixed with respect to the image plane Sim, and the other lens groups move while changing the spacing between adjacent lens groups. A zoom lens contains only one focusing group. The focusing group consists of the first to third three lenses from the image side of the final group GE. When focusing from an object at infinity to a close object, the focusing group moves toward the object side. The vibration reduction group consists of the second to fourth three lenses from the object side of the object-side negative group GN.

[0300] Concerning the zoom lens of Example 24, basic lens data is shown in Table 70, specifications and variable surface spacing in Table 71, aspheric coefficients in Table 72, and each aberration diagram is shown in FIG.

[0301] [Table 70]

[0302] [Table 71]

[0303] [Table 72]

[0304] [Example 25] The configuration and movement locus of the zoom lens of Example 25 are shown in FIG. 50. The zoom lens of Example 25 is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of two lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power and a second M lens group GM2 having negative refractive power. The final group GE is composed of one lens group having positive refractive power. An aperture stop St is included in the final group GE.

[0305] When changing magnification from the wide-angle end to the telephoto end, the object-side positive group GP and the final group GE are fixed with respect to the image plane Sim, and the other lens groups move while changing the spacing between them. A zoom lens includes two focusing groups. The object-side focusing group, which is the first focusing group, is made up of two lenses that are the fourth and fifth from the object side of the final group GE. The image-side focusing group is made up of one lens that is the sixth from the object side of the final group GE. When focusing from an object at infinity to a close object, the object-side focusing group moves toward the image side, and the image-side focusing group moves toward the object side. The vibration reduction group is made up of three lenses that are the second to fourth from the object side of the object-side negative group GN.

[0306] Regarding the zoom lens of Example 25, basic lens data is shown in Table 73, specifications and variable surface spacing in Table 74, aspheric coefficients in Table 75, and each aberration diagram is shown in FIG.

[0307] [Table 73]

[0308] [Table 74]

[0309] [Table 75]

[0310] [Example 26] The configuration and movement locus of the zoom lens of Example 26 are shown in FIG. 52. The zoom lens of Example 26 is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of two lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power and a second M lens group GM2 having negative refractive power. The final group GE is composed of one lens group having positive refractive power. An aperture stop St is included in the final group GE.

[0311] When changing magnification from the wide-angle end to the telephoto end, the object-side positive group GP and the final group GE are fixed with respect to the image plane Sim, and the other lens groups move while changing the spacing between them. A zoom lens includes two focusing groups. The object-side focusing group, which is the first focusing group, is made up of two lenses that are the fourth and fifth from the object side of the final group GE. The image-side focusing group is made up of one lens that is the sixth from the object side of the final group GE. When focusing from an object at infinity to a close object, the object-side focusing group moves toward the image side, and the image-side focusing group moves toward the object side. The vibration reduction group is made up of three lenses that are the second to fourth from the object side of the object-side negative group GN.

[0312] Concerning the zoom lens of Example 26, basic lens data is shown in Table 76, the specifications and variable surface spacing are shown in Table 77, the aspheric coefficients are shown in Table 78, and each aberration diagram is shown in FIG.

[0313] [Table 76]

[0314] [Table 77]

[0315] [Table 78]

[0316] [Example 27] The configuration and movement locus of the zoom lens of Example 27 are shown in FIG. 54. The zoom lens of Example 27 is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of two lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power and a second M lens group GM2 having negative refractive power. The final group GE is composed of one lens group having positive refractive power. An aperture stop St is included in the final group GE.

[0317] When changing magnification from the wide-angle end to the telephoto end, the object-side positive group GP and the final group GE are fixed with respect to the image plane Sim, and the other lens groups move while changing the spacing between them. A zoom lens includes two focusing groups. The object-side focusing group, which is the first focusing group, is made up of two lenses that are the fourth and fifth from the object side of the final group GE. The image-side focusing group is made up of one lens that is the sixth from the object side of the final group GE. When focusing from an object at infinity to a close object, the object-side focusing group moves toward the image side, and the image-side focusing group moves toward the object side. The vibration reduction group is made up of three lenses that are the second to fourth from the object side of the object-side negative group GN.

[0318] Concerning the zoom lens of Example 27, basic lens data is shown in Table 79, the specifications and variable surface spacing are shown in Table 80, the aspheric coefficients are shown in Table 81, and each aberration diagram is shown in FIG.

[0319] [Table 79]

[0320] [Table 80]

[0321] [Table 81]

[0322] [Example 28] The configuration and movement locus of the zoom lens of Example 28 are shown in FIG. 56. The zoom lens of Example 28 is composed of, in order from the object side to the image side, an object side positive group GP, an object side negative group GN, an intermediate group GM, and a final group GE. The object side positive group GP is composed of one lens group having positive refractive power. The object side negative group GN is composed of one lens group having negative refractive power. The intermediate group GM is composed of two lens groups, in order from the object side to the image side, a first M lens group GM1 having positive refractive power and a second M lens group GM2 having negative refractive power. The final group GE is composed of one lens group having positive refractive power. An aperture stop St is included in the final group GE.

[0323] When changing magnification from the wide-angle end to the telephoto end, the object-side positive group GP and the final group GE are fixed with respect to the image plane Sim, and the other lens groups move while changing the spacing between them. A zoom lens includes two focusing groups. The object-side focusing group, which is the first focusing group, is made up of two lenses that are the fourth and fifth from the object side of the final group GE. The image-side focusing group is made up of one lens that is the sixth from the object side of the final group GE. When focusing from an object at infinity to a close object, the object-side focusing group moves toward the image side, and the image-side focusing group moves toward the object side. The vibration reduction group is made up of three lenses that are the second to fourth from the object side of the object-side negative group GN.

[0324] Concerning the zoom lens of Example 28, basic lens data is shown in Table 82, specifications and variable surface spacing are shown in Table 83, aspheric coefficients are shown in Table 84, and each aberration diagram is shown in FIG.

[0325] [Table 82]

[0326] [Table 83]

[0327] [Table 84]

[0328] Tables 85 to 90 show values ​​corresponding to conditional formulas (1) to (36) for the zoom lenses of Examples 1 to 28. The values ​​corresponding to the Examples shown in Tables 85 to 90 may be used as upper or lower limits to set preferred ranges for the conditional formulas.

[0329] [Table 85]

[0330] [Table 86]

[0331] [Table 87]

[0332] [Table 88]

[0333] [Table 89]

[0334] [Table 90]

[0335] The zoom lenses of Examples 1 to 28 are compact, yet maintain high optical performance with various aberrations well corrected. Also, the zoom lenses of Examples 1 to 28 have a large image circle.

[0336] Next, an imaging device according to an embodiment of the present disclosure will be described. Fig. 58 and Fig. 59 show external views of a camera 30 which is an imaging device according to an embodiment of the present disclosure. Fig. 58 shows a perspective view of the camera 30 seen from the front side, and Fig. 59 shows a perspective view of the camera 30 seen from the rear side. The camera 30 is a so-called mirrorless type digital camera, to which an interchangeable lens 20 can be removably attached. The interchangeable lens 20 is configured to include a zoom lens 1 according to an embodiment of the present disclosure housed in a lens barrel.

[0337] The camera 30 includes a camera body 31. A shutter button 32 and a power button 33 are provided on the top surface of the camera body 31. An operation unit 34, an operation unit 35, and a display unit 36 ​​are provided on the back surface of the camera body 31. The display unit 36 ​​is capable of displaying a captured image and an image within the angle of view before the image was captured.

[0338] A photographic opening through which light from a subject is incident is provided in the center of the front surface of the camera body 31. A mount 37 is provided at a position corresponding to the photographic opening, and the interchangeable lens 20 is attached to the camera body 31 via the mount 37.

[0339] An imaging element 38 is provided in the camera body 31. The imaging element 38 outputs an imaging signal corresponding to a subject image formed by the interchangeable lens 20. For example, a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS) is used as the imaging element 38. A signal processing circuit (not shown) and a recording medium (not shown) are provided in the camera body 31. The signal processing circuit processes the imaging signal output from the imaging element 38 to generate an image. The recording medium is for recording the generated image. With the camera 30, it is possible to shoot a still image or a video by pressing the shutter button 32, and image data obtained by this shooting is recorded on the recording medium.

[0340] Although the technology of the present disclosure has been described above with reference to the embodiments and examples, the technology of the present disclosure is not limited to the above embodiments and examples, and various modifications are possible. For example, the radius of curvature, surface spacing, refractive index, Abbe number, aspheric coefficient, etc. of each lens are not limited to the values ​​shown in the above examples, and may take other values.

[0341] Furthermore, the imaging device according to the embodiment of the present disclosure is not limited to the above example, and can take various forms, such as a camera other than a mirrorless type, a film camera, a video camera, and a security camera.

[0342] Regarding the above-mentioned embodiments and examples, the following supplementary notes are further disclosed. [Appendix 1] The lens comprises, in order from the object side to the image side, an object-side positive group having positive refractive power, an object-side negative group having negative refractive power, an intermediate group, and a final group, each of the object-side positive group, the object-side negative group, the intermediate group, and the final group includes at least one lens group; During magnification change, the spacing between all of the adjacent lens groups changes, and the spacing between all of the lenses in each lens group remains unchanged; During focusing, all of the lenses in the object-side positive group and all of the lenses in the intermediate group are fixed with respect to an image plane, The back focus in the air equivalent distance of the entire system when focused on an object at infinity at the wide-angle end is Bfw, The focal length of the entire system when focused on an object at infinity at the wide-angle end is fw. If the maximum half angle of view when focused on an object at infinity at the wide-angle end is ωw, 0.2 <Bfw / (fw×tanωw)<5 (1) A zoom lens that satisfies conditional expression (1) expressed by: [Appendix 2] 2. The zoom lens according to claim 1, wherein the object-side negative group includes a lens group having negative refractive power that is closest to the object among lens groups having negative refractive power included in the zoom lens. [Appendix 3] The zoom lens according to claim 1 or 2, wherein the final group is composed of one lens group. [Appendix 4] 4. The zoom lens according to claim 1, wherein the intermediate group includes at least three lenses. [Appendix 5] Among the negative lenses included in the object-side negative lens group, the paraxial radius of curvature of the object-side surface of the negative lens closest to the object is Rnf, When the paraxial radius of curvature of the image side surface of the negative lens closest to the object side among the negative lenses included in the object-side negative lens group is Rnr, 0.02<(Rnf-Rnr) / (Rnf+Rnr)<3 (2) 5. The zoom lens according to claim 1, which satisfies conditional expression (2) represented by: [Appendix 6] 6. The zoom lens according to claim 1, wherein the lens unit closest to the object side of the object-side positive group moves during magnification variation. [Appendix 7] the zoom lens includes at least one focusing group that moves during focusing; 7. The zoom lens according to claim 1, wherein, of the focusing groups included in the zoom lens, the focusing group closest to an object has negative refractive power. [Appendix 8] the object-side negative lens unit includes at least two negative lenses, Among the negative lenses included in the object-side negative lens group, the image-side surface of the negative lens closest to the object is a concave surface, 8. The zoom lens according to claim 1, wherein the object-side surface of the negative lens closest to the image side among the negative lenses included in the object-side negative group is a concave surface. [Appendix 9] the intermediate group includes at least one lens group having a positive refractive power; Among the lens groups having positive refractive power included in the intermediate group, the lens group having positive refractive power closest to the object side includes at least two positive lenses, Among the positive lenses included in the intermediate group, the positive lens closest to the object has an Abbe number based on the d-line of νMp1, Among the positive lenses included in the intermediate lens group, if the Abbe number based on the d-line of the second positive lens from the object side is νMp2, then 20 <(νMp1+νMp2) / 2<100 (3) 9. The zoom lens according to claim 1, which satisfies conditional expression (3) represented by: [Appendix 10] 10. The zoom lens according to claim 1, wherein the intermediate group includes at least two lens groups whose spacing from adjacent lens groups changes during magnification variation. [Appendix 11] the intermediate group includes at least one lens group having a positive refractive power; The zoom lens according to any one of Appendix 1 to Appendix 10, wherein among the lens groups having positive refractive power included in the intermediate group, the lens group having positive refractive power closest to the object side includes, in succession from the most object side to the image side, two positive lenses. [Appendix 12] the intermediate group includes at least one lens group having a positive refractive power; Among the lens groups having positive refractive power included in the intermediate group, the lens group having positive refractive power closest to the object side includes at least two positive lenses, 12. The zoom lens according to claim 1, wherein among the positive lenses included in the lens group having positive refractive power closest to the object side of the intermediate group, the object-side surface of the positive lens closest to the object side is a convex surface. [Appendix 13] 13. The zoom lens according to claim 1, wherein the object-side negative lens group includes at least four lenses. [Appendix 14] If the maximum F-number when focusing on an object at infinity at the wide-angle end is Fnow, 2 <Fnow<4.8 (4) 14. The zoom lens according to claim 1, which satisfies conditional expression (4) represented by: [Appendix 15] 15. The zoom lens according to claim 1, wherein, among the lens groups included in the intermediate group, the lens group closest to the image side has positive refractive power. [Appendix 16] If the focal length of the object-side positive group at the wide-angle end is fGPw, 0.05 <fw / fGPw<2.5 (5) 16. The zoom lens according to claim 1, which satisfies conditional expression (5) represented by: [Appendix 17] The focal length of the entire system when focused on an object at infinity at the telephoto end is ft. If the focal length of the object-side positive group at the wide-angle end is fGPw, 0.4 <ft / fGPw<4.5 (6) 17. The zoom lens according to claim 1, which satisfies conditional expression (6) represented by: [Appendix 18] 18. The zoom lens according to claim 1, wherein the object-side negative group includes a lens group in which a biconvex air lens is formed. [Appendix 19] the object-side negative group includes a lens group having negative refractive power, 19. The zoom lens according to claim 1, wherein, during focusing, all or a part of the lens group having negative refractive power in the object-side negative group moves along the optical axis. [Appendix 20] 19. The zoom lens according to claim 1, wherein all or part of the final group moves along the optical axis during focusing. [Appendix 21] 21. The zoom lens according to claim 1, wherein the lens unit closest to the image side of the final group moves during zooming. [Appendix 22] An imaging device comprising the zoom lens according to any one of claims 1 to 21. [Explanation of symbols]

[0343] 1 Zoom lens 20 Interchangeable Lenses 30 Camera 31 Camera body 32 Shutter button 33 Power button 34 Control section 35 Control section 36 Display section 37 Mount 38 Image sensor Denw Distance DGEw thickness DGMt thickness DGMw thickness DGNw thickness DGPw thickness GE final group GM intermediate group GM1 1M lens group GM2 2M lens group GM3 3M lens group GN object side negative group GN1 1N lens group GN2 2nd lens group GP object side positive group L11~L53 Lens Penw Paraxial entrance pupil position Pexw paraxial exit pupil position PP Optical Components Sim image plane St Aperture Z optical axis ΔGM Displacement ΔGN Displacement ΔGP Displacement ωw Maximum half angle of view

Claims

1. The lens comprises, in order from the object side to the image side, an object-side positive group having positive refractive power, an object-side negative group having negative refractive power, an intermediate group, and a final group, each of the object-side positive group, the object-side negative group, the intermediate group, and the final group includes at least one lens group; During magnification change, the spacing between all of the adjacent lens groups changes, and the spacing between all of the lenses in each lens group remains unchanged; During focusing, all of the lenses in the object-side positive group and all of the lenses in the intermediate group are fixed with respect to an image plane, The back focus of the entire system in the air equivalent distance when focused on an object at infinity at the wide-angle end is Bfw, The focal length of the entire system when focused on an object at infinity at the wide-angle end is fw. If the maximum half angle of view when focused on an object at infinity at the wide-angle end is ωw, 0.2<Bfw / (fw×tanωw)<5 (1) A zoom lens that satisfies the conditional expression (1) expressed by:

2. 2. The zoom lens according to claim 1, wherein the object-side negative group includes a lens group having negative refractive power that is closest to the object among lens groups having negative refractive power included in the zoom lens.

3. 2. The zoom lens according to claim 1, wherein the final group consists of one lens group.

4. 2. The zoom lens of claim 1, wherein the intermediate group includes at least three lenses.

5. Among the negative lenses included in the object-side negative lens group, the paraxial radius of curvature of the object-side surface of the negative lens closest to the object is Rnf, When the paraxial radius of curvature of the image side surface of the negative lens closest to the object side among the negative lenses included in the object side negative lens group is Rnr, 0.02<(Rnf-Rnr) / (Rnf+Rnr)<3 (2) 2. The zoom lens according to claim 1, which satisfies conditional expression (2) expressed as follows:

6. 2. The zoom lens according to claim 1, wherein the lens unit closest to the object side of said object-side positive group moves during zooming.

7. the zoom lens includes at least one focusing group that moves during focusing; 2. The zoom lens according to claim 1, wherein, of the focusing groups included in the zoom lens, the focusing group closest to the object has negative refractive power.

8. the object-side negative lens unit includes at least two negative lenses, Among the negative lenses included in the object-side negative lens group, the image-side surface of the negative lens closest to the object is a concave surface, 2. The zoom lens according to claim 1, wherein the object-side surface of the negative lens closest to the image side among the negative lenses included in the object-side negative lens group is a concave surface.

9. the intermediate group includes at least one lens group having a positive refractive power; Among the lens groups having positive refractive power included in the intermediate group, the lens group having positive refractive power closest to the object side includes at least two positive lenses, Among the positive lenses included in the intermediate lens group, the positive lens closest to the object has an Abbe number based on the d-line of νMp1; When the Abbe number based on the d-line of the second positive lens from the object side among the positive lenses included in the intermediate lens group is νMp2, 20 <(νMp1+νMp2) / 2<100 (3) 2. The zoom lens according to claim 1, which satisfies conditional expression (3) expressed as follows:

10. 2. The zoom lens according to claim 1, wherein the intermediate group includes at least two lens groups whose spacing from adjacent lens groups changes during magnification.

11. the intermediate group includes at least one lens group having a positive refractive power; 2. The zoom lens according to claim 1, wherein, among the lens groups having positive refractive power included in the intermediate group, the lens group having positive refractive power closest to the object side includes, in succession from the lens group closest to the object side to the lens group closest to the image side, two positive lenses.

12. the intermediate group includes at least one lens group having a positive refractive power; Among the lens groups having positive refractive power included in the intermediate group, the lens group having positive refractive power closest to the object side includes at least two positive lenses, 2. The zoom lens according to claim 1, wherein the object-side surface of the positive lens included in the lens group having positive refractive power and closest to the object in the intermediate group is a convex surface.

13. 2. The zoom lens according to claim 1, wherein the object-side negative lens group includes at least four lenses.

14. When the maximum F-number at the wide-angle end is Fnow and the lens is focused on an object at infinity, 2<Fnow<4.8 (4) 2. The zoom lens according to claim 1, which satisfies conditional expression (4) expressed as follows:

15. 2. The zoom lens according to claim 1, wherein, of the lens groups included in the intermediate group, the lens group closest to the image side has positive refractive power.

16. If the focal length of the object-side positive lens group at the wide-angle end is fGPw, 0.05<fw / fGPw<2.5 (5) 2. The zoom lens according to claim 1, which satisfies conditional expression (5) expressed by:

17. The focal length of the entire system when focused on an object at infinity at the telephoto end is ft. If the focal length of the object-side positive lens group at the wide-angle end is fGPw, 0.4<ft / fGPw<4.5 (6) 2. The zoom lens according to claim 1, which satisfies conditional expression (6) expressed as follows:

18. 2. The zoom lens according to claim 1, wherein the object-side negative group includes a lens group having an air lens of a biconvex shape formed therein.

19. the object-side negative group includes a lens group having negative refractive power, 2. The zoom lens according to claim 1, wherein, during focusing, all or a part of the lens group having negative refractive power in the object-side negative group moves along the optical axis.

20. 2. The zoom lens of claim 1, wherein all or a part of said final group moves along the optical axis during focusing.

21. 2. The zoom lens according to claim 1, wherein the lens unit closest to the image side of the final lens group moves during zooming.

22. An imaging device comprising the zoom lens according to any one of claims 1 to 21.

Images