Zoom lens and imaging device

Abstract

The present invention provides a zoom lens comprising, sequentially from the object side, a first lens group having negative refractive power and a subsequent group. The subsequent group includes at least three lens groups. One of the at least three lens groups in the subsequent group has positive refractive power. Upon zooming, an interval between the first lens group and the subsequent group changes and all intervals each between the lens groups which are of the subsequent group and are adjacent to each other change. The zoom lens satisfies a predetermined conditional expression.

Description

Zoom lens and imaging device

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

[0002] Conventionally, a zoom lens that can be used in an imaging device such as a digital camera is known, as described in Japanese Patent Laid-Open No. 2021-124673.

[0003] There is a demand for zoom lenses that are compact yet have good optical performance, and the level of these demands is increasing year by year.

[0004] An object of the present disclosure is to provide a zoom lens that is small and has good optical performance, and an imaging device that includes this zoom lens.

[0005] A zoom lens according to one aspect of the present disclosure comprises, in order from the object side to the image side, a first lens group having negative refractive power and a subsequent lens group, the subsequent lens group including at least three lens groups, one of which is a P lens group having positive refractive power, and when varying magnification, a distance between the first lens group and the subsequent lens group changes, and all distances between adjacent lens groups in the subsequent lens group change, and the zoom lens satisfies conditional expressions (1) and (2) expressed by: 1.5<ft / fw<6 (1) 0.4<Bfw / (fw×tan ωw)<2 (2) where fw is the focal length of the entire system when focused on an object at infinity at the wide-angle end, ft is the focal length of the entire system when focused on an object at infinity at the telephoto end, Bfw is the back focus of the entire system in air-equivalent distance when focused on an object at infinity at the wide-angle end, and ωw is the maximum half angle of view when focused on an object at infinity at the wide-angle end.

[0006] It is preferable that the P lens group has the greatest amount of movement toward the object side during zooming from the wide-angle end to the telephoto end among the lens groups in the subsequent group.

[0007] When the amount of movement of the P lens group when changing magnification from the wide-angle end to the telephoto end is ΔP, and the sign of the amount of movement when changing magnification is negative when moving toward the object side and positive when moving toward the image side, it is preferable that the zoom lens of the above aspect satisfies conditional expression (3) expressed as 0.9<(−ΔP) / fw<6 (3).

[0008] It is preferable to include an N lens group having negative refractive power on the image side of the P lens group.

[0009] The zoom lens may be configured so that the final lens group located closest to the image side within the zoom lens is located closer to the image side than the N lens group.

[0010] At least a part of the N lens group is preferably a focus group that moves along the optical axis during focusing.

[0011] When the focal length of the N lens group is fN, it is preferable that the zoom lens of the above aspect satisfies the conditional expression (4) expressed as follows: 0.5<(-fN) / fw<7 (4).

[0012] When the maximum F-number when focused on an object at infinity at the telephoto end is Fnot, the zoom lens of the above aspect preferably satisfies conditional expression (5) expressed as follows: 1.2<Fnot<5.8 (5).

[0013] When the maximum F-number when focused on an object at infinity at the telephoto end is Fnot and the maximum F-number when focused on an object at infinity at the wide-angle end is Fnow, it is preferable that the zoom lens of the above aspect satisfies conditional expression (6) expressed as 0.95<Fnot / Fnow<1.8 (6).

[0014] When the focal length of the P lens group is fP, it is preferable that the zoom lens of the above aspect satisfies the conditional expression (7) expressed as follows: 0.5<fP / fw<6 (7).

[0015] It is preferable that the zoom lens of the above aspect satisfies the conditional expression (8) expressed as follows: 35<ωw<54 (8).

[0016] The final lens group preferably has positive refractive power.

[0017] The M lens group may be arranged between the P lens group and the N lens group.

[0018] In the zoom lens of the above aspect, it is preferable that the P lens group, among the lens groups in the subsequent group, includes an N lens group that has the largest amount of movement toward the object side when changing magnification from the wide-angle end to the telephoto end, and that the N lens group is located closer to the image side than the P lens group and has negative refractive power, and that the M lens group is located between the P lens group and the N lens group, and that the amount of movement of the P lens group when changing magnification from the wide-angle end to the telephoto end is set to ΔP, and the sign of the amount of movement during magnification change is set to negative when moving toward the object side and positive when moving toward the image side, satisfy conditional expression (3) expressed as 0.9<(−ΔP) / fw<6 (3).

[0019] The M lens group preferably has a positive refractive power.

[0020] When the focal length of the M lens group is fM, it is preferable that the zoom lens of the above aspect satisfies the conditional expression (9) expressed as follows: 0.01<fw / fM<0.35 (9).

[0021] When the refractive index of the positive lens closest to the image among the positive lenses in the M lens group with respect to the d-line is NMp and the Abbe number of the positive lens closest to the image among the positive lenses in the M lens group with respect to the d-line is νMp, it is preferable that the zoom lens of the above aspect satisfies conditional expressions (10) and (11) expressed as follows: 1.73<NMp<2.5 (10) 10<νMp<50 (11)

[0022] The zoom lens of the above aspect preferably includes an aperture stop located closest to the object side of the M lens group.

[0023] It is preferable that the first lens group includes a negative meniscus lens element with a concave surface facing the image side, the lens element being closest to the object.

[0024] When the focal length of the first lens group is taken as f1, it is preferable that the zoom lens of the above aspect satisfies the conditional expression (12) expressed as follows: 1<(-f1) / fw<2.5 (12).

[0025] When the distance on the optical axis from the lens surface of the first lens group closest to the object to the lens surface of the first lens group closest to the image is defined as DG1, it is preferable that the zoom lens of the above aspect satisfies conditional expression (13) expressed as follows: 0.71<DG1 / (fw×tan ωw)<2.5 (13).

[0026] When the distance on the optical axis from the lens surface of the P lens group closest to the object side to the lens surface of the P lens group closest to the image side is defined as DGP, it is preferable that the zoom lens of the above aspect satisfies conditional expression (14) expressed as follows: 0.35<DGP / (fw×tan ωw)<2.5 (14).

[0027] When the distance on the optical axis from the lens surface of the first lens group closest to the object to the paraxial entrance pupil position when focused on an object at infinity at the wide-angle end is Denw, it is preferable that the zoom lens of the above aspect satisfies conditional expression (15) expressed as 1<Denw / fw<2.2 (15).

[0028] When the average value of the specific gravity of all the lenses in the first lens group is taken as G1ave, it is preferable that the zoom lens of the above aspect satisfies conditional expression (16) expressed as: 1<G1ave<5 (16).

[0029] When the average value of the specific gravity of all the lenses in the P lens group is taken as GPave, it is preferable that the zoom lens of the above aspect satisfies the conditional expression (17) expressed as follows: 1<GPave<5 (17).

[0030] When the average value of the specific gravity of all the lenses in the focus group is Gfave, the distance on the optical axis from the lens surface in the focus group closest to the object side to the lens surface in the focus group closest to the image side is DGfoc, and the focal length of the focus group is ffoc, it is preferable that the zoom lens of the above aspect satisfies conditional expression (18) expressed as 0.03<Gfave×DGfoc / |ffoc|<0.9 (18).

[0031] When the focal length of the first lens group is f1 and the focal length of the P lens group is fP, it is preferable that the zoom lens of the above aspect satisfies conditional expression (19) expressed as follows: 0.3<(-f1) / fP<1.5 (19)

[0032] When the focal length of the first lens group is f1 and the focal length of the M lens group is fM, it is preferable that the zoom lens of the above aspect satisfies the conditional expression (20) expressed as follows: 0<(-f1) / fM<0.7 (20).

[0033] When the focal length of the P lens group is fP and the focal length of the M lens group is fM, it is preferable that the zoom lens of the above aspect satisfies conditional expression (21) expressed as follows: 0<fP / fM<2 (21).

[0034] When the focal length of the focus group is ffoc, it is preferable that the zoom lens of the above aspect satisfies the conditional expression (22) expressed as follows: 1.2<(-ffoc) / (fw×tan ωw)<5.5 (22).

[0035] The first lens group includes at least one aspherical lens, and when the paraxial radius of curvature of the object-side surface of the aspherical lens in the first lens group is Rc1f, the paraxial radius of curvature of the image-side surface of the aspherical lens in the first lens group is Rc1r, the radius of curvature of the object-side surface of the aspherical lens in the first lens group at the position of maximum effective diameter of the aspherical lens in the first lens group is Ry1f, and the radius of curvature of the image-side surface of the aspherical lens in the first lens group at the position of maximum effective diameter of the aspherical lens in the first lens group is Ry1r, it is preferable that the zoom lens of the above aspect satisfies conditional expression (23) expressed as follows: 1.05<(1 / Rc1f-1 / Rc1r) / (1 / Ry1f-1 / Ry1r)<8 (23)

[0036] The P lens group includes at least one aspherical lens, and when the paraxial radius of curvature of the object-side surface of the aspherical lens in the P lens group is RcPf, the radius of curvature of the object-side surface of the aspherical lens in the P lens group at the position of the maximum effective diameter is RyPf, the refractive index of the aspherical lens in the P lens group with respect to the d-line is NP, and the focal length of the P lens group is fP, it is preferable that the zoom lens of the above aspect satisfies conditional expression (24) expressed as follows: 0.01<(1 / RcPf-1 / RyPf)×NP×fP<5 (24)

[0037] The N lens group includes at least one aspherical lens, and when the paraxial radius of curvature of the object-side surface of the aspherical lens in the N lens group is RcNf, the paraxial radius of curvature of the image-side surface of the aspherical lens in the N lens group is RcNr, the radius of curvature of the object-side surface of the aspherical lens in the N lens group at the position of maximum effective diameter of the aspherical lens in the N lens group is RyNf, and the radius of curvature of the image-side surface of the aspherical lens in the N lens group at the position of maximum effective diameter of the aspherical lens in the N lens group is RyNr, it is preferable that the zoom lens of the above aspect satisfies conditional expression (25) expressed as 0.7<(1 / RcNf-1 / RcNr) / (1 / RyNf-1 / RyNr)<0.996 (25).

[0038] The final lens group includes at least one aspherical lens, and when the paraxial radius of curvature of the object-side surface of the aspherical lens in the final lens group is RcEf, the paraxial radius of curvature of the image-side surface of the aspherical lens in the final lens group is RcEr, the radius of curvature of the object-side surface of the aspherical lens in the final lens group at the position of maximum effective diameter of the aspherical lens in the final lens group is RyEf, and the radius of curvature of the image-side surface of the aspherical lens in the N lens group at the position of maximum effective diameter of the aspherical lens in the N lens group is RyEr, it is preferable that the zoom lens of the above aspect satisfies conditional expression (26) expressed as follows: 1.01<(1 / RcEf-1 / RcEr) / (1 / RyEf-1 / RyEr)<2 (26)

[0039] The first lens group includes at least one negative lens, and when the Abbe number of the negative lens in the first lens group based on the d-line is v1n and the partial dispersion ratio between the g-line and the F-line of the negative lens in the first lens group is θgF1n, it is preferable that the zoom lens of the above aspect satisfies conditional expressions (27) and (28) expressed by: 55<v1n<110 (27) 0.003<θgF1n-(0.6438-0.001682×v1n)<0.05 (28).

[0040] The P lens group includes at least one negative lens, and when the Abbe number of the negative lens in the P lens group based on the d-line is vPn and the partial dispersion ratio between the g-line and the F-line of the negative lens in the P lens group is θgFPn, it is preferable that the zoom lens of the above aspect satisfies conditional expressions (29) and (30) expressed by: 55<vPn<110 (29) 0.003<θgFPn−(0.6438−0.001682×vPn)<0.05 (30).

[0041] The N lens group includes at least one negative lens, and when the Abbe number of the negative lens in the N lens group based on the d-line is vNn and the partial dispersion ratio between the g-line and the F-line of the negative lens in the N lens group is θgFNn, it is preferable that the zoom lens of the above aspect satisfies conditional expressions (31) and (32) expressed as follows: 55<vNn<110 (31) 0.003<θgFNn−(0.6438−0.001682×vNn)<0.05 (32).

[0042] The M lens group includes at least one negative lens, and when the Abbe number of the negative lens in the M lens group based on the d-line is vMn and the partial dispersion ratio between the g-line and the F-line of the negative lens in the M lens group is θgFMn, it is preferable that the zoom lens of the above aspect satisfies conditional expressions (33) and (34) expressed by: 55<νMn<110 (33) 0.003<θgFMn−(0.6438−0.001682×νMn)<0.06 (34).

[0043] The final lens group includes at least one positive lens, and when the Abbe number of the positive lens in the final lens group based on the d-line is vEp and the partial dispersion ratio between the g-line and the F-line of the positive lens in the final lens group is θgFEp, it is preferable that the zoom lens of the above aspect satisfies conditional expressions (35) and (36) expressed by: 55<vEp<110 (35) 0.003<θgFEp−(0.6438−0.001682×vEp)<0.05 (36).

[0044] The first lens group includes at least one positive lens, and when the refractive index of the positive lens in the first lens group with respect to the d-line is N1p and the Abbe number of the positive lens in the first lens group with respect to the d-line is v1p, it is preferable that the zoom lens of the above aspect satisfies conditional expressions (37) and (38) expressed by the following: 1.8<N1p<2.3 (37) 10<v1p<45 (38)

[0045] The final lens group may be configured to be fixed relative to the image plane during zooming.

[0046] The first lens group may be configured to include a biconcave lens arranged closer to the image side than the negative meniscus lens, and a positive lens arranged closer to the image side than the biconcave lens.

[0047] The first lens group at the telephoto end may be positioned closer to the image side than the first lens group at the wide-angle end, or the first lens group at the telephoto end may be positioned closer to the object side than the first lens group at the wide-angle end.

[0048] The subsequent group includes an aperture stop, and at least one negative lens element with a concave surface facing the object side is disposed closer to the image side than the aperture stop; if the distance on the optical axis between the aperture stop and the negative lens element with a concave surface facing the object side when focused on an object at infinity at the wide-angle end is DSInw, and the sum of the distance on the optical axis from the lens surface of the first lens group closest to the object to the lens surface of the subsequent group closest to the image when focused on an object at infinity at the wide-angle end and TLw, and the back focus of the entire system in terms of air equivalent distance, it is preferable that the zoom lens of the above aspect satisfies conditional expression (39) expressed as follows: 0.001<DSInw / TLw<0.12 (39)

[0049] The subsequent group includes an aperture stop, and at least one negative lens element with a concave surface facing the image side is disposed closer to the object than the aperture stop; if the distance on the optical axis between the aperture stop and the negative lens element with a concave surface facing the image side when focused on an object at infinity at the wide-angle end is DSOnw, and the sum of the distance on the optical axis from the lens surface in the first lens group closest to the object to the lens surface in the subsequent group closest to the image when focused on an object at infinity at the wide-angle end and the back focus of the entire system in air equivalent distance when TLw is the distance on the optical axis from the lens surface in the first lens group closest to the object to the lens surface in the subsequent group closest to the image when focused on an object at infinity at the wide-angle end, it is preferable that the zoom lens of the above aspect satisfies conditional expression (40) expressed as: 0.001<DSOnw / TLw<0.18 (40).

[0050] The subsequent group includes an aperture stop, and at least one cemented lens is disposed on the image side of the aperture stop, and when the lens is focused on an object at infinity at the wide-angle end, the distance on the optical axis between the aperture stop and the cemented surface of the cemented lens on the image side of the aperture stop is defined as DSICew, and when the lens is focused on an object at infinity at the wide-angle end, the sum of the distance on the optical axis from the lens surface in the first lens group closest to the object to the lens surface in the subsequent group closest to the image, and the back focus of the entire system in air equivalent distance, it is preferable that the zoom lens of the above aspect satisfies conditional expression (41) expressed as: 0.001<DSICew / TLw<0.12 (41).

[0051] The subsequent group includes an aperture stop, and at least one cemented lens is disposed on the object side of the aperture stop, and when the zoom lens is focused on an object at infinity at the wide-angle end, the distance on the optical axis between the aperture stop and the cemented surface of the cemented lens on the object side of the aperture stop is defined as DSOcew, and when the zoom lens is focused on an object at infinity at the wide-angle end, the sum of the distance on the optical axis from the lens surface in the first lens group closest to the object to the lens surface in the subsequent group closest to the image side and the back focus of the entire system in air equivalent distance is defined as TLw, it is preferable that the zoom lens of the above aspect satisfies conditional expression (42) expressed as follows: 0.001<DSOCew / TLw<0.18 (42)

[0052] When the amount of movement of the N lens group when changing magnification from the wide-angle end to the telephoto end is ΔN, the amount of movement of the P lens group when changing magnification from the wide-angle end to the telephoto end is ΔP, and the sign of the amount of movement when changing magnification is negative when moving toward the object side and positive when moving toward the image side, it is preferable that the zoom lens of the above aspect satisfies conditional expression (43) expressed as follows: 0.1<ΔN / ΔP<0.75 (43)

[0053] When the zoom lens of the above aspect is focused on an object at infinity at the wide-angle end, if the sum of the distance on the optical axis from the paraxial exit pupil position to the lens surface of the subsequent group closest to the image side and the back focus of the entire system in air equivalent distance is defined as Dexw, it is preferable that the zoom lens of the above aspect satisfies conditional expression (44) expressed as follows: 1.5<Dexw / (fw×tan ωw)<5 (44)

[0054] When the maximum F-number when focused on an object at infinity at the telephoto end is Fnot and the distance on the optical axis from the lens surface of the P lens group closest to the object to the lens surface of the P lens group closest to the image is DGP, it is preferable that the zoom lens of the above aspect satisfies conditional expression (45) expressed as follows: 0.4<Fnot×DGP / ft<4 (45)

[0055] When the maximum F-number when focused on an object at infinity at the telephoto end is Fnot, the distance on the optical axis from the lens surface of the P lens group closest to the object to the lens surface of the P lens group closest to the image is DGP, and the distance on the optical axis from the lens surface of the M lens group closest to the object to the lens surface of the M lens group closest to the image is DGM, it is preferable that the zoom lens of the above aspect satisfies conditional expression (46) expressed as 0.4<Fnot×(DGP+DGM) / ft<4 (46).

[0056] A configuration may be adopted in which one lens group is included between the first lens group and the P lens group.

[0057] When the zoom lens of the above aspect is focused on an object at infinity at the telephoto end, it is preferable that the sum of the distance on the optical axis from the lens surface in the first lens group closest to the object to the lens surface in the subsequent lens group closest to the image and the back focus of the entire system in air equivalent distance is TLt.

[0058] When the focal length of the final lens unit is taken as fE, it is preferable that the zoom lens of the above aspect satisfies the conditional expression (48) expressed as follows: 0.1<fw / fE<0.7 (48).

[0059] When the lateral magnification of the focus group when focused on an object at infinity at the wide-angle end is βfw, and the combined lateral magnification of all lenses on the image side of the focus group when focused on an object at infinity at the wide-angle end is βfRw, the zoom lens of the above aspect satisfies the following condition: 0.3<|(1−βfw ２ ) × βfRw ２ It is preferable to satisfy the conditional expression (49) expressed as: |<3 (49).

[0060] When the lateral magnification of the focus group when focused on an object at infinity at the telephoto end is βft, and the combined lateral magnification of all lenses on the image side of the focus group when focused on an object at infinity at the telephoto end is βfRt, the zoom lens of the above aspect satisfies the following condition: 0.5<|(1-βft ２ ) × βfRt ２ It is preferable to satisfy the conditional expression (50) expressed as: |<4 (50).

[0061] The focal length of the focus group is ffoc, the composite focal length of all lenses on the image side of the focus group when focused on an object at infinity at the wide-angle end is ffRw, and the sum of the distance on the optical axis from the paraxial exit pupil position to the lens surface of the subsequent group closest to the image side when focused on an object at infinity at the wide-angle end and the back focus of the entire system in air equivalent distance is Dexw, and γw=(1-βfw ２ ) × βfRw ２ , when BRw={βfw / (ffoc×γw)−1 / (βfRw×ffRw)−(1 / Dexw)}, it is preferable that the zoom lens of the above aspect satisfies conditional expression (51) expressed as follows: 0<(−BRw)×(fw×tanωw)<0.7 (51)

[0062] The focal length of the focus group is ffoc, the composite focal length of all lenses on the image side of the focus group when focused on an object at infinity at the telephoto end is ffRt, the sum of the distance on the optical axis from the paraxial exit pupil position to the lens surface of the subsequent group closest to the image when focused on an object at infinity at the telephoto end and the back focus of the entire system in air equivalent distance is Dext, and the maximum half angle of view when focused on an object at infinity at the telephoto end is ωt, and γt=(1-βft ２ ) × βfRt ２ , when BRt={βft / (ffoc×γt)−1 / (βfRt×ffRt)−(1 / Dext)}, it is preferable that the zoom lens of the above aspect satisfies conditional expression (52) expressed as follows: 0<(−BRt)×(ft×tanωt)<0.5 (52).

[0063] The zoom lens of the above aspect preferably includes an aperture stop and at least three lenses between the first lens group and the aperture stop.

[0064] The zoom lens of the above aspect preferably includes an aperture stop and at least three positive lenses between the first lens group and the aperture stop.

[0065] The zoom lens of the above aspect preferably includes an aperture stop and at least three lenses between the aperture stop and the N lens group.

[0066] The zoom lens of the above aspect preferably includes an aperture stop and at least two positive lenses between the aperture stop and the N lens group.

[0067] It is preferable that the focus group includes two or less lenses.

[0068] It is preferable that the final lens group include two or less lenses.

[0069] It is preferable that the lens surface of the first lens group closest to the image side be a concave surface.

[0070] Of the movement loci of each lens group that moves when changing magnification from the wide-angle end to the telephoto end, the number of mutually different movement loci may be five, four, or three.

[0071] At least one of the lens closest to the object side and the lens second from the object side is a negative lens, and when the refractive index of at least one of the lens closest to the object side and the lens second from the object side with respect to the d-line is Nobn, it is preferable that the zoom lens of the above aspect satisfies conditional expression (53) expressed as 1.7<Nobn<2.2 (53).

[0072] It is preferable that the lens closest to the object side is a negative lens and satisfies the above conditional expression (53).

[0073] An imaging device according to another aspect of the present disclosure includes the zoom lens according to the above aspect of the present disclosure.

[0074] In this specification, the terms "consisting of" and "consisting of" are intended to mean that, in addition to the listed components, other components may also be included, such as lenses that have substantially no refractive power, optical elements other than lenses, such as apertures, filters, and cover glasses, and mechanical parts, such as lens flanges, lens barrels, image sensors, and image stabilization mechanisms.

[0075] In this specification, "a lens group having positive refractive power" and "a lens group having positive refractive power" mean that the lens group as a whole has positive refractive power. Similarly, "a lens group having negative refractive power" and "a lens group having negative refractive power" mean that the lens group as a whole has negative refractive power. In this specification, the terms "first lens group," "lens group," "P lens group," "N lens group," "final lens group," "focus group," and "M lens group" are not limited to configurations consisting of multiple lenses, and may also be configurations consisting of only one lens.

[0076] A hybrid aspherical lens (a lens in which a spherical lens and an aspherical film formed on the spherical lens are integrally constructed and function as a single aspherical lens as a whole) is not considered a cemented lens, but is treated as a single lens. Unless otherwise specified, the sign of the refractive power and surface shape of a lens including an aspherical surface are those in the paraxial region. The sign of the paraxial radius of curvature is positive for a surface with a convex shape facing the object side, and negative for a surface with a convex shape facing the image side.

[0077] In this specification, "total system" refers to a zoom lens. The "focal length" used in the conditional expressions is a paraxial focal length. The "distance on the optical axis" used in the conditional expressions is a geometric distance unless otherwise specified. The values ​​used in the conditional expressions are values ​​based on the d-line when focused on an object at infinity, unless otherwise specified.

[0078] The terms "d-line," "C-line," "F-line," and "g-line" used in this specification are emission lines. The wavelength of the d-line is treated as 587.56 nm (nanometers), the wavelength of the C-line is treated as 656.27 nm (nanometers), the wavelength of the F-line is treated as 486.13 nm (nanometers), and the wavelength of the g-line is treated as 435.84 nm (nanometers).

[0079] According to the present disclosure, it is possible to provide a zoom lens that is small and has good optical performance, and an imaging device that includes this zoom lens.

[0080] FIG. 1 is a diagram illustrating the configuration and movement locus of a zoom lens according to an embodiment, corresponding to the zoom lens of Example 1. FIG. 2 is a diagram for explaining symbols in conditional expressions. FIG. 3 is a diagram for explaining the position of an effective diameter and a maximum effective diameter. FIG. 4 is a diagram illustrating aberration diagrams of the zoom lens of Example 1. FIG. 5 is a diagram illustrating the configuration and movement locus of the zoom lens of Example 2. FIG. 6 is a diagram illustrating the configuration and movement locus of the zoom lens of Example 3. FIG. 7 is a diagram illustrating the configuration and movement locus of the zoom lens of Example 4. FIG. 8 is a diagram illustrating the configuration and movement locus of the zoom lens of Example 5. FIG. 9 is a diagram illustrating the configuration and movement locus of the zoom lens of Example 6. FIG. 10 is a diagram illustrating the configuration and movement locus of the zoom lens of Example 7. FIG. 11 is a diagram illustrating the configuration and movement locus of the zoom lens of Example 8. FIG. 12 is a diagram illustrating the configuration and movement locus of the zoom lens of Example 9. FIG. 13 is a diagram illustrating the configuration and movement locus of the zoom lens of Example 9. FIG. 1 is a diagram showing the configuration and movement locus of a zoom lens of Example 10. FIG. 2 is a diagram showing various aberration diagrams of the zoom lens of Example 10. FIG. 3 is a diagram showing the configuration and movement locus of a zoom lens of Example 11. FIG. 4 is a diagram showing the configuration and movement locus of a zoom lens of Example 12. FIG. 5 is a diagram showing various aberration diagrams of the zoom lens of Example 12. FIG. 6 is a diagram showing the configuration and movement locus of a zoom lens of Example 13. FIG. 7 is a diagram showing the configuration and movement locus of a zoom lens of Example 13. FIG. 8 is a diagram showing the configuration and movement locus of a zoom lens of Example 14. FIG. 9 is a diagram showing various aberration diagrams of the zoom lens of Example 14. FIG. 10 is a diagram showing the configuration and movement locus of a zoom lens of Example 15. FIG. 11 is a diagram showing the configuration and movement locus of a zoom lens of Example 16. FIG. 12 is a diagram showing the configuration and movement locus of a zoom lens of Example 16. FIG. 13 is a diagram showing the configuration and movement locus of a zoom lens of Example 17. FIG. 14 is a diagram showing the configuration and movement locus of a zoom lens of Example 18. FIG. 15 is a diagram showing various aberration diagrams of the zoom lens of Example 18. 20A and 20B are diagrams illustrating the configuration and movement locus of a zoom lens according to Example 19.Fig. 20 is a diagram illustrating aberrations of the zoom lens of Example 19. Fig. 21 is a perspective view of the front side of an image pickup apparatus according to an embodiment. Fig. 22 is a perspective view of the rear side of an image pickup apparatus according to an embodiment.

[0081] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[0082] 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. In FIG. 1, the upper row labeled "Wide" shows the wide-angle end state, and the lower row labeled "Tele" shows the telephoto end state. The example shown in FIG. 1 corresponds to the zoom lens of Example 1, which will be described later. FIG. 1 shows a state in which the lens is focused on an object at infinity, with the left side being the object side and the right side being the image side. FIG. 1 also shows an axial light beam wa and a light beam wb at the maximum half angle of view ωw at the wide-angle end, as well as an axial light beam ta and a light beam tb at the maximum half angle of view ωt at the telephoto end.

[0083] 1 shows an example in which a parallel-plate-shaped optical member PP is disposed between the zoom lens and the image plane Sim, assuming that the zoom lens is applied to an imaging device. The optical member PP is a member that is assumed to include various filters and / or cover glass. The various filters include a low-pass filter, an infrared cut filter, and / or a filter that cuts off a specific wavelength range. 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.

[0084] The zoom lens of the present disclosure comprises, in order from the object side to the image side along the optical axis Z, a first lens group G1 having negative refractive power and a subsequent lens group GR. By making the refractive power of the first lens group G1, which is closest to the object, negative, it becomes easier to reduce the diameter of the lens closest to the object, which is advantageous for miniaturization.

[0085] During magnification variation, the distance between the first lens group G1 and the subsequent lens group GR changes, and all distances between adjacent lens groups in the subsequent lens group GR also change. In this specification, the terms "first lens group G1" and "lens group" included in the subsequent lens group GR refer to components of a zoom lens, each of which includes at least one lens and is separated by an air gap that changes during magnification variation. During magnification variation, each lens group is moved or fixed individually, and the distances between lenses within each lens group do not change. In other words, in this specification, a group in which the distance between adjacent groups changes during magnification variation, but the total distance between adjacent lenses within itself does not change, is defined as one lens group.

[0086] 1 includes, in order from the object side to the image side, a first lens group G1 having negative refractive power, a second lens group G2 having positive refractive power, a third lens group G3 having positive refractive power, a fourth lens group G4 having negative refractive power, and a fifth lens group G5 having positive refractive power. In the example of FIG. 1, the subsequent group GR includes the second lens group G2, the third lens group G3, the fourth lens group G4, and the fifth lens group G5.

[0087] As an example, each lens group in FIG. 1 is composed of the following lenses. The first lens group G1, from the object side to the image side, consists of three lenses, lenses L11 to L13. The second lens group G2, from the object side to the image side, consists of four lenses, lenses L21 to L24. The third lens group G3, from the object side to the image side, consists of an aperture stop St and three lenses, lenses L31 to L33. The fourth lens group G4, from the object side to the image side, consists of two lenses, lenses L41 and L42. The fifth lens group G5 consists of a single lens, lens L51. The aperture stop St in FIG. 1 does not indicate the shape or size, but rather its position in the optical axis direction.

[0088] In the example of Fig. 1, during magnification change, the first lens group G1, the second lens group G2, the third lens group G3, and the fourth lens group G4 move along the optical axis Z while changing the spacing between adjacent lens groups, and the fifth lens group G5 is fixed with respect to the image plane Sim. In Fig. 1, for the moving lens groups, the approximate movement locus of each lens group during magnification change from the wide-angle end to the telephoto end is indicated by arrows between the upper and lower rows.

[0089] The zoom lens of the present disclosure preferably includes an aperture stop St and at least three lenses between the first lens group G1 and the aperture stop St. This is advantageous for correcting spherical aberration while reducing the F-number.

[0090] The zoom lens of the present disclosure preferably includes an aperture stop St and at least three positive lenses between the first lens group G1 and the aperture stop St. This is advantageous for correcting axial chromatic aberration while reducing the F-number.

[0091] It is preferable that the first lens group G1 includes a negative meniscus lens with a concave surface facing the image side, closest to the object. This is advantageous for correcting distortion. In this specification, a "negative meniscus lens" refers to a meniscus lens with negative refractive power.

[0092] When the first lens group G1 includes a negative meniscus lens with a concave surface facing the image side closest to the object, it is preferable that the first lens group G1 also includes a biconcave lens positioned closer to the image side than the negative meniscus lens, and a positive lens positioned closer to the image side than the biconcave lens, which is advantageous for suppressing lateral chromatic aberration and astigmatism.

[0093] It is preferable that the lens surface closest to the image side of the first lens group G1 is a concave surface, which is advantageous for suppressing fluctuations in astigmatism during zooming.

[0094] As in the example of Figure 1, the first lens group G1 at the telephoto end may be configured to be located closer to the image side than the first lens group G1 at the wide-angle end. This is advantageous for shortening the overall length of the lens system. Unlike the example of Figure 1, if the first lens group G1 at the telephoto end is configured to be located closer to the object side than the first lens group G1 at the wide-angle end, this is advantageous for achieving a high zoom ratio.

[0095] It is preferable that at least one of the lens closest to the object side of the zoom lens and the lens second from the object side of the zoom lens be a negative lens, which is advantageous for achieving a wider angle.

[0096] The rear group GR is configured to include at least three lens groups, which enable the three lens groups to perform the main functions of zooming, imaging, and correcting the image plane position during zooming, respectively.

[0097] One of the at least three lens groups in the rear group GR is a P lens group having positive refractive power, which is capable of performing the main variable magnification function.

[0098] The P lens group can be configured so that, among the lens groups in the subsequent lens group GR, it is the lens group that moves the greatest amount toward the object side when changing magnification from the wide-angle end to the telephoto end. In this case, the P lens group is suitable as the lens group that mainly performs the magnification change function. For example, in the example of Figure 1, among the lens groups in the subsequent lens group GR, the lens group that moves the greatest amount toward the object side when changing magnification from the wide-angle end to the telephoto end is the second lens group G2.

[0099] The zoom lens of the present disclosure preferably includes an N lens group having negative refractive power located closer to the image side than the P lens group. In this case, the N lens group can correct the image plane position during zooming. In the example of Figure 1, if the second lens group G2 corresponds to the P lens group, the fourth lens group G4 corresponds to the N lens group.

[0100] It is preferable that at least a portion of the N lens group is a focus group that moves along the optical axis Z during focusing. The N lens group is located at a position where both the diameter of the on-axis light beam at the telephoto end and the height from the optical axis Z of the off-axial light beam at the wide-angle end are small. By making at least a portion of such N lens group a focus group, the lens diameter of the focus group can be reduced and the group can be made more compact, which is advantageous for autofocusing.

[0101] In this specification, the group that moves along the optical axis Z during focusing is referred to as the focus group. Focusing is achieved by the movement of the focus group. In the example of FIG. 1 , the focus group is the fourth lens group G4. The parentheses and right-pointing arrow below the fourth lens group G4 in FIG. 1 indicate that the fourth lens group G4 is a focus group that moves toward the image side during focusing from an object at infinity to a closest object. Note that although the fourth lens group G4 functions as a focus group throughout the entire magnification range, in FIG. 1 , to avoid cluttering the diagram, the parentheses and arrow indicating the focus group are only included in the lower diagram.

[0102] It is preferable that the number of lenses included in the focus group be two or less, which is advantageous for reducing the weight of the focus group.

[0103] The zoom lens of the present disclosure preferably includes an aperture stop St and at least three lenses between the aperture stop St and the N lens group, which is advantageous for suppressing fluctuations in spherical aberration during zooming.

[0104] The zoom lens of the present disclosure preferably includes an aperture stop St and at least two positive lenses between the aperture stop St and the N lens group, which is advantageous for suppressing fluctuations in axial chromatic aberration during zooming.

[0105] The zoom lens of the present disclosure preferably includes a final lens group located closest to the image side of the N lens group. Positioning the lens groups close to the imaging position in this manner is advantageous for correcting aberrations associated with off-axis light beams, such as distortion and chromatic aberration of magnification. In the example of Figure 1, the fifth lens group G5 corresponds to the final lens group.

[0106] It is preferable that the final lens group has positive refractive power, which reduces the angle of incidence of light rays onto the image plane Sim at the wide-angle end and is advantageous for suppressing distortion and chromatic aberration of magnification at the wide-angle end.

[0107] It is preferable that the final lens group includes two or less lenses, which is advantageous for shortening the overall length of the lens system.

[0108] The final lens group may be configured to be fixed relative to the image plane Sim during zooming. This is advantageous in suppressing fluctuations in field curvature during zooming, and also contributes to simplifying the device.

[0109] The zoom lens of the present disclosure may be configured to include an M lens group between the P lens group and the N lens group. This is advantageous for suppressing fluctuations in spherical aberration during zooming. In the example of Figure 1, if the second lens group G2 corresponds to the P lens group and the fourth lens group G4 corresponds to the N lens group, the third lens group G3 corresponds to the M lens group.

[0110] The M lens group may be configured to have positive refractive power. In this case, the positive refractive power can be shared with the P lens group, thereby suppressing the error sensitivity of the P lens group on the telephoto side, which tends to become a problem as the aperture increases. This contributes to the realization of a zoom lens with good optical performance.

[0111] The zoom lens of the present disclosure may be configured to include an aperture diaphragm St closest to the object side of the M lens group. By locating the aperture diaphragm St closer to the image side than the P lens group that performs the magnification change in this way, it is possible to reduce the aperture diameter of the aperture diaphragm St itself while also minimizing changes that occur with magnification change.

[0112] 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, to avoid redundant explanation, the same symbols are used for elements with the same definitions, and some redundant explanations of symbols will be omitted. Also, to avoid redundant explanation, hereinafter, "the zoom lens of the present disclosure" will also be referred to simply as "the zoom lens."

[0113] If the focal length of the entire system at the wide-angle end when focused on an object at infinity is fw and the focal length of the entire system at the telephoto end when focused on an object at infinity is ft, it is preferable that the zoom lens satisfy the following conditional expression (1). By ensuring that the corresponding value of conditional expression (1) is not equal to or less than the lower limit, a high zoom ratio can be achieved. By ensuring that the corresponding value of conditional expression (1) is not equal to or greater than the upper limit, the amount of movement of each lens group during zooming can be reduced, which is advantageous for miniaturization. In order to obtain better characteristics, it is more preferable that the zoom lens satisfy the following conditional expression (1-1), even more preferable that it satisfy the following conditional expression (1-2), and even more preferable that it satisfy the following conditional expression (1-3). 1.5<ft / fw<6 (1) 1.9<ft / fw<5 (1-1) 2.1<ft / fw<4.5 (1-2) 2.8<ft / fw<4.2 (1-3)

[0114] It is preferable that the zoom lens satisfy the following conditional expression (2). Here, Bfw is the back focus of the entire system at the air-equivalent distance when focused on an object at infinity at the wide-angle end. ωw is the maximum half angle of view when focused on an object at infinity at the wide-angle end. tan is the tangent. Making sure that the corresponding value of conditional expression (2) is not equal to or less than the lower limit is advantageous for ensuring peripheral illumination. Furthermore, since the lens group closest to the image surface can be located farther away from the image surface Sim, it is advantageous for suppressing ghosting or flare caused by reflection from the image surface Sim. Making sure that the corresponding value of conditional expression (2) is not equal to or greater than the upper limit is advantageous for achieving a high zoom ratio while maintaining the overall length of the lens system, as it is possible to ensure space for the lens groups that move during zooming. In order to obtain better characteristics, it is more preferable that the zoom lens satisfy the following conditional expression (2-1), and even more preferable that it satisfy the following conditional expression (2-2). 0.4<Bfw / (fw×tanωw)<2 (2) 0.65<Bfw / (fw×tanωw)<1.7 (2-1) 0.84<Bfw / (fw×tanωw)<1.48 (2-2)

[0115] If the amount of movement of the P lens group during zooming from the wide-angle end to the telephoto end is ΔP, it is preferable that the zoom lens satisfy the following conditional expression (3). Here, the sign of the amount of movement during zooming is negative when moving toward the object side and positive when moving toward the image side. As an example, FIG. 2 shows the amount of movement ΔP when the second lens group G2 corresponds to the P lens group. By ensuring that the corresponding value of conditional expression (3) is not below the lower limit, the amount of movement of the P lens group does not become too small, making it easy to ensure a desired zoom ratio. If an attempt were made to ensure a desired zoom ratio while keeping the amount of movement of the P lens group small, the refractive power of the P lens group would have to be increased, making it difficult to correct spherical aberration and axial chromatic aberration at the telephoto end. By ensuring that the corresponding value of conditional expression (3) is not below the lower limit, such a problem can be avoided. By ensuring that the corresponding value of conditional expression (3) does not exceed the upper limit, the amount of movement of the P lens group does not become too large, and therefore it is possible to avoid an increase in the diameter of the first lens group G1 that would otherwise be required to increase the overall length of the lens system, thereby facilitating size reduction. To obtain better characteristics, it is more preferable that the zoom lens satisfies the following conditional expressions (3-1), and even more preferable that the following conditional expressions (3-2) are satisfied: 0.9<(-ΔP) / fw<6 (3) 1.2<(-ΔP) / fw<5 (3-1) 1.75<(-ΔP) / fw<3.5 (3-2)

[0116] When the focal length of the N lens group is fN, it is preferable that the zoom lens satisfy the following conditional expression (4). By ensuring that the corresponding value of conditional expression (4) is not below the lower limit, the refractive power of the N lens group does not become too strong, thereby suppressing fluctuations in various aberrations associated with zooming, and in particular fluctuations in field curvature. This is advantageous for achieving both a large aperture and a high zoom ratio. By ensuring that the corresponding value of conditional expression (4) is not above the upper limit, the refractive power of the N lens group does not become too weak, thereby making it easier to avoid an increase in the overall length of the lens system due to an increase in the amount of movement of the N lens group during zooming. In order to obtain better characteristics, it is more preferable that the zoom lens satisfy the following conditional expression (4-1), and it is even more preferable that the zoom lens satisfy the following conditional expression (4-2). 0.5<(-fN) / fw<7 (4) 1.2<(-fN) / fw<5.8 (4-1) 1.63<(-fN) / fw<4.88 (4-2)

[0117] If the maximum F-number when focused on an object at infinity at the telephoto end is Fnot, it is preferable that the zoom lens satisfy the following conditional expression (5). By ensuring that the corresponding value of conditional expression (5) is not equal to or less than the lower limit, the axial light beam at the telephoto end can be made thinner, which is advantageous for reducing the size and weight of the lens. By ensuring that the corresponding value of conditional expression (5) is not equal to or greater than the upper limit, a brighter optical image can be obtained at the telephoto end. Since the effects of each configuration of the present disclosure are often suitable for zoom lenses with small F-numbers, a more suitable zoom lens can be provided by ensuring that the corresponding value of conditional expression (5) is not equal to or greater than the upper limit. In order to obtain better characteristics, it is more preferable that the zoom lens satisfy the following conditional expression (5-1), and it is even more preferable that the zoom lens satisfy the following conditional expression (5-2). 1.2<Fnot<5.8 (5) 2<Fnot<4.2 (5-1) 2.73<Fnot<3.7 (5-2)

[0118] When the maximum F-number when focused on an object at infinity at the wide-angle end is Fnow, it is preferable that the zoom lens satisfies the following conditional expression (6). By ensuring that the corresponding value of conditional expression (6) is not equal to or less than the lower limit, the axial light beam at the telephoto end can be made thinner, which is advantageous for reducing the size and weight of the lens. By ensuring that the corresponding value of conditional expression (6) is not equal to or greater than the upper limit, it is possible to suppress fluctuations in the brightness of the optical image when changing magnification. In order to obtain better characteristics, it is more preferable that the zoom lens satisfies the following conditional expression (6-1), and it is even more preferable that the zoom lens satisfies the following conditional expression (6-2): 0.95<Fnot / Fnow<1.8 (6) 0.95<Fnot / Fnow<1.46 (6-1) 0.95<Fnot / Fnow<1.1 (6-2)

[0119] When the focal length of the P lens group is fP, it is preferable that the zoom lens satisfy the following conditional expression (7). By ensuring that the corresponding value of conditional expression (7) is not below the lower limit, the refractive power of the P lens group does not become too strong, making it easy to correct spherical aberration on the telephoto side. By ensuring that the corresponding value of conditional expression (7) is not above the upper limit, the refractive power of the P lens group does not become too weak, making it easy to provide the P lens group with a large variable magnification effect. In order to obtain better characteristics, it is more preferable that the zoom lens satisfy the following conditional expressions (7-1), and even more preferable that the following conditional expressions (7-2) are satisfied: 0.5<fP / fw<6 (7) 1<fP / fw<4 (7-1) 1.26<fP / fw<2.97 (7-2)

[0120] If the maximum half angle of view when focused on an object at infinity at the wide-angle end is ωw, it is preferable that the zoom lens satisfy the following conditional expression (8). Making sure that the corresponding value of conditional expression (8) is not equal to or less than the lower limit is advantageous for widening the angle. Making sure that the corresponding value of conditional expression (8) is not equal to or greater than the upper limit is advantageous for reducing the diameter, since the height of the light rays passing through the first lens group G1 can be made lower. In order to obtain better characteristics, it is more preferable that the zoom lens satisfy the following conditional expression (8-1), and it is even more preferable that the zoom lens satisfy the following conditional expression (8-2). 35<ωw<54 (8) 38<ωw<50 (8-1) 41<ωw<47 (8-2)

[0121] When the focal length of the M lens group is fM, it is preferable that the zoom lens satisfy the following conditional expression (9). By ensuring that the corresponding value of conditional expression (9) is not below the lower limit, the refractive power of the M lens group does not become too weak, and it is possible to suppress the error sensitivity of the P lens group on the telephoto side, which is likely to become a problem as the aperture becomes larger. This contributes to the realization of a zoom lens with good optical performance. By ensuring that the corresponding value of conditional expression (9) is not above the upper limit, the refractive power of the M lens group does not become too strong, and it is possible to strengthen the refractive power of the P lens group. This strengthens the magnification-varying effect of the P lens group, making it easier to shorten the overall length of the lens system and ensure a desired magnification ratio. In order to obtain better characteristics, it is more preferable that the zoom lens satisfy the following conditional expression (9-1), and it is even more preferable that it satisfy the following conditional expression (9-2). 0.01<fw / fM<0.35 (9) 0.015<fw / fM<0.3 (9-1) 0.019<fw / fM<0.26 (9-2)

[0122] When the refractive index for the d-line of the positive lens closest to the image among the positive lenses in the M lens group is NMp, it is preferable that the zoom lens satisfies the following conditional expression (10). Generally, the higher the refractive index of an optical material, the smaller the Abbe number. By ensuring that the corresponding value of conditional expression (10) is not below the lower limit, a material with a smaller Abbe number can be used, making it easier to correct chromatic aberrations, including axial chromatic aberration, that occur during zooming. By ensuring that the corresponding value of conditional expression (10) is not above the upper limit, the refractive index does not become too high, making it possible to prevent over-correction of chromatic aberrations. In order to obtain better characteristics, it is more preferable that the zoom lens satisfies the following conditional expressions (10-1), and even more preferable that the zoom lens satisfies the following conditional expressions (10-2). 1.73<NMp<2.5 (10) 1.85<NMp<2.3 (10-1) 1.9<NMp<2.1 (10-2)

[0123] When the Abbe number based on the d-line of the positive lens closest to the image among the positive lenses in the M lens group is vMp, it is preferable that the zoom lens satisfies the following conditional expression (11). By ensuring that the corresponding value of conditional expression (11) is not equal to or less than the lower limit, the Abbe number does not become too small, and therefore excessive correction of chromatic aberrations can be suppressed. By ensuring that the corresponding value of conditional expression (11) is not equal to or greater than the upper limit, the Abbe number does not become too large, and therefore correction of chromatic aberrations, including axial chromatic aberrations associated with zooming, becomes easy. In order to obtain better characteristics, it is more preferable that the zoom lens satisfies the following conditional expressions (11-1), and even more preferable that the zoom lens satisfies the following conditional expressions (11-2): 10<vMp<50 (11) 15<vMp<41 (11-1) 17<vMp<37 (11-2)

[0124] It is preferable that the zoom lens satisfy conditional expressions (10) and (11). It is more preferable that the zoom lens satisfy at least one of conditional expressions (10-1), (10-2), (11-1), and (11-2) in addition to satisfying conditional expressions (10) and (11).

[0125] When the focal length of the first lens group G1 is f1, it is preferable that the zoom lens satisfy the following conditional expression (12). By ensuring that the corresponding value of conditional expression (12) is not below the lower limit, the refractive power of the first lens group G1 does not become too strong, eliminating the need to arrange many lenses in the first lens group G1 to reduce distortion and lateral chromatic aberration, and allowing the diameter of the lens in the first lens group G1 closest to the object to be made smaller. By ensuring that the corresponding value of conditional expression (12) is not above the upper limit, the refractive power of the first lens group G1 does not become too weak, making it easier to ensure a suitable focal length of the zoom lens at the wide-angle end. In order to obtain better characteristics, it is more preferable that the zoom lens satisfy the following conditional expression (12-1), and even more preferable that the zoom lens satisfy the following conditional expression (12-2). 1<(-f1) / fw<2.5 (12) 1.15<(-f1) / fw<2.3 (12-1) 1.22<(-f1) / fw<2.19 (12-2)

[0126] If the distance on the optical axis from the lens surface of the first lens group G1 closest to the object to the lens surface of the first lens group G1 closest to the image is DG1, it is preferable that the zoom lens satisfy the following conditional expression (13). As an example, the above distance DG1 is shown in FIG. 2. By ensuring that the corresponding value of conditional expression (13) is not equal to or less than the lower limit, the space available for arranging lenses in the first lens group G1 increases, which is advantageous for reducing distortion and chromatic aberration of magnification. By ensuring that the corresponding value of conditional expression (13) is not equal to or greater than the upper limit, it is possible to reduce the total thickness of the first lens group G1, thereby reducing the weight of the lens on the object side of the zoom lens. In order to obtain better characteristics, it is more preferable that the zoom lens satisfy the following conditional expression (13-1), and it is even more preferable that the zoom lens satisfy the following conditional expression (13-2). 0.71<DG1 / (fw×tanωw)<2.5 (13) 0.8<DG1 / (fw×tanωw)<2.2 (13-1) 0.97<DG1 / (fw×tanωw)<1.94 (13-2)

[0127] If the distance on the optical axis from the lens surface of the P lens group closest to the object to the lens surface of the P lens group closest to the image is defined as DGP, it is preferable that the zoom lens satisfy the following conditional expression (14). As an example, FIG. 2 shows the above-mentioned distance DGP when the second lens group G2 corresponds to the P lens group. By ensuring that the corresponding value of conditional expression (14) is not below the lower limit, the space available for arranging lenses in the P lens group increases, which is advantageous for suppressing fluctuations in axial chromatic aberration and spherical aberration during zooming. By ensuring that the corresponding value of conditional expression (14) is not above the upper limit, it is possible to reduce the total thickness of the P lens group, thereby achieving a high zoom ratio and a large aperture while reducing the lens weight. In order to obtain better characteristics, it is more preferable that the zoom lens satisfy the following conditional expression (14-1), and it is even more preferable that the zoom lens satisfy the following conditional expression (14-2). 0.35<DGP / (fw×tanωw)<2.5 (14) 0.8<DGP / (fw×tanωw)<2.1 (14-1) 1.4<DGP / (fw×tanωw)<1.9 (14-2)

[0128] When the on-optical distance from the lens surface of the first lens group G1 closest to the object to the paraxial entrance pupil position Penw when focused on an object at infinity at the wide-angle end is Denw, it is preferable that the zoom lens satisfy the following conditional expression (15): As an example, FIG. 2 shows the above-mentioned distance Denw and the paraxial entrance pupil position Penw. By ensuring that the corresponding value of conditional expression (15) is not equal to or less than the lower limit, the on-axis light beam wa and the off-axial light beam passing through the first lens group G1 can be suitably separated, which is advantageous for correcting lateral chromatic aberration. By ensuring that the corresponding value of conditional expression (15) is not equal to or greater than the upper limit, the paraxial entrance pupil position Penw is positioned closer to the object, which makes it possible to reduce the height from the optical axis Z of the off-axial light beam passing through the first lens group G1. This is advantageous for reducing the diameter and weight. To obtain better characteristics, it is more preferable that the zoom lens satisfy the following conditional expression (15-1), and it is even more preferable that the zoom lens satisfy the following conditional expression (15-2): 1<Denw / fw<2.2 (15) 1.2<Denw / fw<1.9 (15-1) 1.28<Denw / fw<1.82 (15-2)

[0129] When the average value of the specific gravities of all the lenses in the first lens group G1 is defined as G1ave, it is preferable that the zoom lens satisfy the following conditional expression (16). By ensuring that the corresponding value of conditional expression (16) is not below the lower limit, it is possible to select a material with a high refractive index and a material with a relatively large specific gravity and a small Abbe number, which is advantageous for correcting lateral chromatic aberration in the first lens group G1. By ensuring that the corresponding value of conditional expression (16) is not above the upper limit, it is possible to reduce the weight of the first lens group G1, which allows the center of gravity of the optical system to be positioned closer to the image side. In order to obtain better characteristics, it is more preferable that the zoom lens satisfy the following conditional expressions (16-1), and even more preferable that the zoom lens satisfy the following conditional expressions (16-2): 1<G1ave<5 (16) 2.4<G1ave<4.5 (16-1) 3<G1ave<4.15 (16-2)

[0130] When the average value of the specific gravities of all the lenses in the P lens group is GPave, it is preferable that the zoom lens satisfy the following conditional expression (17). By ensuring that the corresponding value of conditional expression (17) is not below the lower limit, it is possible to select a material with a high refractive index and a material with a relatively large specific gravity and a small Abbe number, which is advantageous for correcting axial chromatic aberration in the P lens group. By ensuring that the corresponding value of conditional expression (17) is not above the upper limit, it is possible to reduce the weight of the P lens group, which is advantageous for suppressing movement of the center of gravity during zooming. In order to obtain better characteristics, it is more preferable that the zoom lens satisfy the following conditional expression (17-1), and it is even more preferable that the zoom lens satisfy the following conditional expression (17-2). 1<GPave<5 (17) 2.4<GPave<4.5 (17-1) 3<GPave<4.3 (17-2)

[0131] It is preferable that the zoom lens satisfy the following conditional expression (18). Here, Gfave is the average value of the specific gravity of all lenses in the focus group. DGfoc is the distance on the optical axis from the lens surface in the focus group closest to the object to the lens surface in the focus group closest to the image. ffoc is the focal length of the focus group. As an example, FIG. 2 shows the above distance DGfoc. By ensuring that the corresponding value of conditional expression (18) is not equal to or less than the lower limit, the refractive power of the focus group can be strengthened, thereby reducing the amount of movement of the focus group during focusing, which is advantageous for shortening the overall length of the lens system. By ensuring that the corresponding value of conditional expression (18) is not equal to or greater than the upper limit, the weight of the focus group can be reduced, which is advantageous for faster and quieter autofocusing. In order to obtain better characteristics, it is more preferable that the zoom lens satisfy the following conditional expression (18-1), and it is even more preferable that the zoom lens satisfy the following conditional expression (18-2). 0.03<Gfave×DGfoc / |ffoc|<0.9 (18) 0.04<Gfave×DGfoc / |ffoc|<0.52 (18-1) 0.045<Gfave×DGfoc / |ffoc|<0.15 (18-2)

[0132] It is preferable that the zoom lens satisfies the following conditional expression (19). By ensuring that the corresponding value of conditional expression (19) is not equal to or less than the lower limit, it is advantageous to suppress fluctuations in spherical aberration when changing magnification. By ensuring that the corresponding value of conditional expression (19) is not equal to or greater than the upper limit, it is advantageous to suppress fluctuations in distortion when changing magnification. In order to obtain better characteristics, it is more preferable that the zoom lens satisfies the following conditional expressions (19-1), and it is even more preferable that the zoom lens satisfies the following conditional expressions (19-2). 0.3<(-f1) / fP<1.5 (19) 0.35<(-f1) / fP<1.31 (19-1) 0.48<(-f1) / fP<1.07 (19-2)

[0133] It is preferable that the zoom lens satisfy the following conditional expression (20). By ensuring that the corresponding value of conditional expression (20) is not below the lower limit, it is possible to strengthen the refractive power of the M lens group while suppressing the refractive power of the first lens group G1, thereby suppressing the error sensitivity of the P lens group located between the first lens group G1 and the M lens group. This contributes to the realization of a zoom lens with good optical performance. By ensuring that the corresponding value of conditional expression (20) is not above the upper limit, it is possible to strengthen the refractive power of the first lens group G1 while suppressing the refractive power of the M lens group, thereby strengthening the magnification-varying effect of the P lens group located between the first lens group G1 and the M lens group. This makes it easier to ensure a desired magnification ratio. In order to obtain better characteristics, it is more preferable that the zoom lens satisfy the following conditional expression (20-1), and it is even more preferable that the zoom lens satisfy the following conditional expression (20-2). 0<(-f1) / fM<0.7 (20) 0.05<(-f1) / fM<0.6 (20-1) 0.2<(-f1) / fM<0.55 (20-2)

[0134] It is preferable that the zoom lens satisfy the following conditional expression (21). Conditional expression (21) defines the balance between the refractive power of the P lens group and the refractive power of the M lens group. By ensuring that the corresponding value of conditional expression (21) is not equal to or less than the lower limit, the refractive power of the P lens group can be suppressed, and therefore the error sensitivity of the P lens group can be suppressed. This contributes to the realization of a zoom lens with good optical performance. By ensuring that the corresponding value of conditional expression (21) is not equal to or greater than the upper limit, the refractive power of the M lens group can be suppressed, and therefore the error sensitivity of the M lens group can be suppressed. This contributes to the realization of a zoom lens with good optical performance. In order to obtain better characteristics, it is more preferable that the zoom lens satisfy the following conditional expression (21-1), and it is even more preferable that the zoom lens satisfy the following conditional expression (21-2). 0<fP / fM<2 (21) 0.05<fP / fM<1.2 (21-1) 0.2<fP / fM<0.59 (21-2)

[0135] It is preferable that the zoom lens satisfies the following conditional expression (22). By ensuring that the corresponding value of conditional expression (22) is not equal to or less than the lower limit, the refractive power of the focus group can be suppressed, thereby suppressing aberration fluctuations during focusing. By ensuring that the corresponding value of conditional expression (22) is not equal to or greater than the upper limit, the refractive power of the focus group can be strengthened, thereby suppressing the amount of movement of the focus group during focusing, which is advantageous for shortening the overall length of the lens system. In order to obtain better characteristics, it is more preferable that the zoom lens satisfies the following conditional expression (22-1), and it is even more preferable that the zoom lens satisfies the following conditional expression (22-2). 1.2<(-ffoc) / (fw×tanωw)<5.5 (22) 1.4<(-ffoc) / (fw×tanωw)<5 (22-1) 1.7<(-ffoc) / (fw×tanωw)<4.7 (22-2)

[0136] It is preferable that the first lens group G1 includes at least one aspherical lens that satisfies the following conditional expression (23). Here, the paraxial radius of curvature of the object-side surface of the aspherical lens in the first lens group G1 is Rc1f. The paraxial radius of curvature of the image-side surface of the aspherical lens in the first lens group G1 is Rc1r. The radius of curvature of the object-side surface of the aspherical lens in the first lens group G1 at the position of the maximum effective diameter is Ry1f. The radius of curvature of the image-side surface of the aspherical lens in the first lens group G1 at the position of the maximum effective diameter is Ry1r. By ensuring that the corresponding value of conditional expression (23) is not equal to or less than the lower limit, the refractive power of the lens on the peripheral side is weakened, which is advantageous for correcting distortion. By ensuring that the corresponding value of conditional expression (23) is not equal to or greater than the upper limit, the refractive power of the lens on the peripheral side is strengthened, which is advantageous for suppressing astigmatism of off-axial rays that occur on the peripheral side of the lens. By disposing an aspherical lens that satisfies conditional expression (23) in the first lens group G1 at a position where on-axis rays and off-axis rays are separated, it is advantageous for correcting distortion and astigmatism. To obtain better characteristics, it is more preferable that at least one aspherical lens in the first lens group G1 satisfies the following conditional expression (23-1), and it is even more preferable that it satisfies the following conditional expression (23-2): 1.05<(1 / Rc1f-1 / Rc1r) / (1 / Ry1f-1 / Ry1r)<8 (23) 1.1<(1 / Rc1f-1 / Rc1r) / (1 / Ry1f-1 / Ry1r)<6 (23-1) 1.15<(1 / Rc1f-1 / Rc1r) / (1 / Ry1f-1 / Ry1r)<4.7 (23-2)

[0137] For explanatory purposes, FIG. 3 shows an example of the position Px of the maximum effective diameter. In FIG. 3, the left side is the object side and the right side is the image side. FIG. 3 also shows an axial ray Xa and an off-axial ray Xb passing through the lens Lx. In the example of FIG. 3, ray Xb1, which is the upper ray of the off-axial ray Xb, is the outermost ray. In this specification, the "effective diameter" of a lens surface is defined as twice the distance from the optical axis Z to the point of intersection of the outermost ray and the lens surface among the rays that enter the lens surface from the object side and exit to the image side. "Outside" here refers to the radially outward direction centered on the optical axis Z, i.e., the side away from the optical axis Z. In the example of FIG. 3, the effective diameter ED of the object-side surface of the lens Lx is twice the distance from the point of intersection of ray Xb1 and the object-side surface of the lens Lx to the optical axis Z. Furthermore, the position of the intersection of the outermost ray and the lens surface is the position of the maximum effective diameter Px. In the example of Fig. 3, the upper ray of the off-axial light beam Xb is the outermost ray, but which ray becomes the outermost ray varies depending on the optical system. The outermost ray is determined taking into account the entire magnification range.

[0138] It is preferable that the P lens group include at least one aspherical lens that satisfies the following conditional expression (24). Here, the paraxial radius of curvature of the object-side surface of the aspherical lens in the P lens group is RcPf. The radius of curvature at the position of the maximum effective diameter of the object-side surface of the aspherical lens in the P lens group is RyPf. The refractive index of the aspherical lens in the P lens group with respect to the d-line is NP. By ensuring that the corresponding value of conditional expression (24) is not below the lower limit, the refractive power of the peripheral side of the object-side surface of the aspherical lens in the P lens group can be changed to the negative side, which is advantageous for suppressing fluctuations in spherical aberration during magnification. By ensuring that the corresponding value of conditional expression (24) is not above the upper limit, the refractive power of the peripheral side of the object-side surface of the aspherical lens in the P lens group can be prevented from changing to the negative side, which is advantageous for suppressing error sensitivity of the P lens group. By disposing an aspherical lens that satisfies conditional expression (24) in the P lens group that performs the zooming function, it is advantageous to suppress fluctuations in spherical aberration during zooming while suppressing the error sensitivity of the P lens group. To obtain better characteristics, it is more preferable that at least one aspherical lens in the P lens group satisfies the following conditional expression (24-1), and it is even more preferable that it satisfies the following conditional expression (24-2): 0.01<(1 / RcPf-1 / RyPf)×NP×fP<5 (24) 0.075<(1 / RcPf-1 / RyPf)×NP×fP<2.5 (24-1) 0.2<(1 / RcPf-1 / RyPf)×NP×fP<1.3 (24-2)

[0139] It is preferable that the N lens group includes at least one aspherical lens that satisfies the following conditional expression (25). Here, the paraxial radius of curvature of the object-side surface of the aspherical lens in the N lens group is RcNf. The paraxial radius of curvature of the image-side surface of the aspherical lens in the N lens group is RcNr. The radius of curvature of the object-side surface of the aspherical lens in the N lens group at the position of the maximum effective diameter is RyNf. The radius of curvature of the image-side surface of the aspherical lens in the N lens group at the position of the maximum effective diameter is RyNr. By ensuring that the corresponding value of conditional expression (25) is not equal to or less than the lower limit, the refractive power of the peripheral side of the lens is weakened, which is advantageous for suppressing the error sensitivity of the N lens group. By ensuring that the corresponding value of conditional expression (25) is not equal to or greater than the upper limit, the difference between the refractive power of the peripheral side of the lens and the refractive power near the optical axis of the lens is reduced, which is advantageous for suppressing fluctuations in astigmatism during magnification. By disposing an aspherical lens that satisfies conditional expression (25) in the N lens group, it is advantageous to suppress fluctuations in astigmatism during magnification while suppressing the error sensitivity of the N lens group. In order to obtain better characteristics, it is more preferable that at least one aspherical lens in the N lens group satisfies the following conditional expression (25-1), and it is even more preferable that it satisfies the following conditional expression (25-2): 0.7<(1 / RcNf-1 / RcNr) / (1 / RyNf-1 / RyNr)<0.996 (25) 0.8<(1 / RcNf-1 / RcNr) / (1 / RyNf-1 / RyNr)<0.99 (25-1) 0.85<(1 / RcNf-1 / RcNr) / (1 / RyNf-1 / RyNr)<0.98 (25-2)

[0140] It is preferable that the final lens group includes at least one aspherical lens that satisfies the following conditional expression (26). Here, the paraxial radius of curvature of the object-side surface of the aspherical lens in the final lens group is RcEf. The paraxial radius of curvature of the image-side surface of the aspherical lens in the final lens group is RcEr. The radius of curvature of the object-side surface of the aspherical lens in the final lens group at the position of the maximum effective diameter is RyEf. The radius of curvature of the image-side surface of the aspherical lens in the Nth lens group at the position of the maximum effective diameter is RyEr. By ensuring that the corresponding value of conditional expression (26) is not equal to or less than the lower limit, the refractive power of the lens on the peripheral side becomes weaker than the refractive power near the optical axis of the lens, which is advantageous for correcting field curvature. By ensuring that the corresponding value of conditional expression (26) is not equal to or greater than the upper limit, the refractive power of the lens on the peripheral side becomes stronger, which prevents field curvature from being over-corrected. Placing an aspherical lens that satisfies conditional expression (26) in the final lens group is advantageous for correcting curvature of field. To obtain better characteristics, it is more preferable that at least one aspherical lens in the final lens group satisfies the following conditional expression (26-1), and it is even more preferable that it satisfies the following conditional expression (26-2): 1.01<(1 / RcEf-1 / RcEr) / (1 / RyEf-1 / RyEr)<2 (26) 1.05<(1 / RcEf-1 / RcEr) / (1 / RyEf-1 / RyEr)<1.5 (26-1) 1.15<(1 / RcEf-1 / RcEr) / (1 / RyEf-1 / RyEr)<1.3 (26-2)

[0141] It is preferable that the first lens group G1 includes at least one negative lens that satisfies the following conditional expression (27). Here, the Abbe number of the negative lens in the first lens group G1 based on the d-line is designated as v1n. Ensuring that the corresponding value of conditional expression (27) is not equal to or less than the lower limit is advantageous for correcting lateral chromatic aberration. Ensuring that the corresponding value of conditional expression (27) is not equal to or greater than the upper limit can prevent lateral chromatic aberration from being overcorrected. In order to obtain better characteristics, it is more preferable that at least one negative lens in the first lens group G1 satisfies the following conditional expressions (27-1), and even more preferable that it satisfies the following conditional expressions (27-2). 55<v1n<110 (27) 57<v1n<95 (27-1) 60<v1n<85 (27-2)

[0142] It is preferable that the first lens group G1 includes at least one negative lens that satisfies the following conditional expression (28). Here, the partial dispersion ratio between the g-line and the F-line of the negative lens in the first lens group G1 is θgF1n. Ensuring that the corresponding value of conditional expression (28) is not equal to or less than the lower limit is advantageous for correction of second-order lateral chromatic aberration. Ensuring that the corresponding value of conditional expression (28) is not equal to or greater than the upper limit can prevent second-order lateral chromatic aberration from being overcorrected. In order to obtain even better characteristics, it is more preferable that at least one negative lens in the first lens group G1 satisfies the following conditional expression (28-1), and it is even more preferable that it satisfies the following conditional expression (28-2). 0.003<θgF1n-(0.6438-0.001682×ν1n)<0.05 (28) 0.005<θgF1n-(0.6438-0.001682×ν1n)<0.04 (28-1) 0.015<θgF1n-(0.6438-0.001682×ν1n)<0.033 (28-2)

[0143] 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 between the g-line and F-line of the lens is θgF, then θgF is defined by the following formula: θgF = (Ng - NF) / (NF - NC)

[0144] It is preferable that at least one negative lens in the first lens group G1 satisfies conditional expressions (27) and (28). It is even more preferable that at least one negative lens in the first lens group G1 satisfies conditional expressions (27) and (28), and also satisfies at least one of conditional expressions (27-1), (27-2), (28-1), and (28-2).

[0145] It is preferable that the P lens group includes at least one negative lens that satisfies the following conditional expression (29). Here, the Abbe number of the negative lens in the P lens group based on the d-line is denoted as vPn. Ensuring that the corresponding value of conditional expression (29) is not equal to or less than the lower limit is advantageous for correcting longitudinal chromatic aberration. Ensuring that the corresponding value of conditional expression (29) is not equal to or greater than the upper limit can prevent longitudinal chromatic aberration from being overcorrected. In order to obtain better characteristics, it is more preferable that at least one negative lens in the P lens group satisfies the following conditional expression (29-1), and it is even more preferable that it satisfies the following conditional expression (29-2). 55<vPn<110 (29) 57<vPn<95 (29-1) 60<vPn<85 (29-2)

[0146] It is preferable that the P lens group includes at least one negative lens that satisfies the following conditional expression (30). Here, the partial dispersion ratio between the g-line and the F-line of the negative lens in the P lens group is θgFPn. Ensuring that the corresponding value of conditional expression (30) is not equal to or less than the lower limit is advantageous for correction of second-order axial chromatic aberration. Ensuring that the corresponding value of conditional expression (30) is not equal to or greater than the upper limit can prevent second-order axial chromatic aberration from being overcorrected. In order to obtain better characteristics, it is more preferable that at least one negative lens in the P lens group satisfies the following conditional expression (30-1), and it is even more preferable that it satisfies the following conditional expression (30-2). 0.003<θgFPn-(0.6438-0.001682×νPn)<0.05 (30) 0.005<θgFPn-(0.6438-0.001682×νPn)<0.04 (30-1) 0.015<θgFPn-(0.6438-0.001682×νPn)<0.033 (30-2)

[0147] It is preferable that at least one negative lens in the P lens group satisfies conditional expressions (29) and (30). It is even more preferable that at least one negative lens in the P lens group satisfies conditional expressions (29) and (30), and also satisfies at least one of conditional expressions (29-1), (29-2), (30-1), and (30-2).

[0148] It is preferable that the N lens group includes at least one negative lens that satisfies the following conditional expression (31). Here, the Abbe number of the negative lens in the N lens group based on the d-line is designated as vNn. Ensuring that the corresponding value of conditional expression (31) is not equal to or less than the lower limit is advantageous for correcting lateral chromatic aberration. Ensuring that the corresponding value of conditional expression (31) is not equal to or greater than the upper limit can prevent lateral chromatic aberration from being overcorrected. In order to obtain better characteristics, it is more preferable that at least one negative lens in the N lens group satisfies the following conditional expression (31-1), and it is even more preferable that it satisfies the following conditional expression (31-2). 55<vNn<110 (31) 57<vNn<95 (31-1) 60<vNn<85 (31-12)

[0149] It is preferable that the N lens group includes at least one negative lens that satisfies the following conditional expression (32). Here, the partial dispersion ratio between the g-line and the F-line of the negative lens in the N lens group is θgFNn. Ensuring that the corresponding value of conditional expression (32) is not equal to or less than the lower limit is advantageous for correction of second-order chromatic aberration of magnification. Ensuring that the corresponding value of conditional expression (32) is not equal to or greater than the upper limit can prevent second-order chromatic aberration of magnification from being overcorrected. In order to obtain better characteristics, it is more preferable that at least one negative lens in the N lens group satisfies the following conditional expression (32-1), and it is even more preferable that it satisfies the following conditional expression (32-2). 0.003<θgFNn-(0.6438-0.001682×νNn)<0.05 (32) 0.005<θgFNn-(0.6438-0.001682×νNn)<0.04 (32-1) 0.015<θgFNn-(0.6438-0.001682×νNn)<0.033 (32-2)

[0150] It is preferable that at least one negative lens in the N lens group satisfies conditional expressions (31) and (32). It is even more preferable that at least one negative lens in the N lens group satisfies conditional expressions (31) and (32), and also satisfies at least one of conditional expressions (31-1), (31-2), (32-1), and (32-2).

[0151] It is preferable that the M lens group includes at least one negative lens that satisfies the following conditional expression (33). Here, the Abbe number of the negative lens in the M lens group based on the d-line is designated as νMn. Ensuring that the corresponding value of conditional expression (33) is not equal to or less than the lower limit is advantageous for correcting longitudinal chromatic aberration. Ensuring that the corresponding value of conditional expression (33) is not equal to or greater than the upper limit can prevent longitudinal chromatic aberration from being overcorrected. In order to obtain better characteristics, it is more preferable that at least one negative lens in the M lens group satisfies the following conditional expression (33-1), and it is even more preferable that it satisfies the following conditional expression (33-2). 55<νMn<110 (33) 57<νMn<95 (33-1) 60<νMn<91 (33-2)

[0152] It is preferable that the M lens group includes at least one negative lens that satisfies the following conditional expression (34). Here, the partial dispersion ratio between the g-line and the F-line of the negative lens in the M lens group is θgFMn. Ensuring that the corresponding value of conditional expression (34) is not equal to or less than the lower limit is advantageous for correction of second-order axial chromatic aberration. Ensuring that the corresponding value of conditional expression (34) is not equal to or greater than the upper limit can prevent second-order axial chromatic aberration from being over-corrected. In order to obtain even better characteristics, it is more preferable that at least one negative lens in the M lens group satisfies the following conditional expression (34-1), and it is even more preferable that it satisfies the following conditional expression (34-2). 0.003<θgFMn-(0.6438-0.001682×νMn)<0.06 (34) 0.005<θgFMn-(0.6438-0.001682×νMn)<0.05 (34-1) 0.015<θgFMn-(0.6438-0.001682×νMn)<0.045 (34-2)

[0153] It is preferable that at least one negative lens in the M lens group satisfies conditional expressions (33) and (34). It is even more preferable that at least one negative lens in the M lens group satisfies conditional expressions (33) and (34), and also satisfies at least one of conditional expressions (33-1), (33-2), (34-1), and (34-2).

[0154] It is preferable that the final lens group includes at least one positive lens that satisfies the following conditional expression (35). Here, the Abbe number of the positive lens in the final lens group based on the d-line is defined as vEp. By ensuring that the corresponding value of conditional expression (35) is not equal to or less than the lower limit, it is advantageous for correction of lateral chromatic aberration. By ensuring that the corresponding value of conditional expression (35) is not equal to or greater than the upper limit, it is possible to prevent lateral chromatic aberration from being overcorrected. In order to obtain better characteristics, it is more preferable that at least one positive lens in the final lens group satisfies the following conditional expression (35-1), and it is even more preferable that it satisfies the following conditional expression (35-2). 55<vEp<110 (35) 57<vEp<95 (35-1) 60<vEp<85 (35-2)

[0155] It is preferable that the final lens group includes at least one positive lens that satisfies the following conditional expression (36). Here, the partial dispersion ratio between the g-line and the F-line of the positive lens in the final lens group is θgFEp. Ensuring that the corresponding value of conditional expression (36) is not equal to or less than the lower limit is advantageous for correction of second-order chromatic aberration of magnification. Ensuring that the corresponding value of conditional expression (36) is not equal to or greater than the upper limit can prevent second-order chromatic aberration of magnification from being overcorrected. In order to obtain better characteristics, it is more preferable that at least one positive lens in the final lens group satisfies the following conditional expression (36-1), and it is even more preferable that it satisfies the following conditional expression (36-2). 0.003<θgFEp-(0.6438-0.001682×νEp)<0.05 (36) 0.005<θgFEp-(0.6438-0.001682×νEp)<0.04 (36-1) 0.015<θgFEp-(0.6438-0.001682×νEp)<0.033 (36-2)

[0156] It is preferable that at least one positive lens in the final lens group satisfies conditional expressions (35) and (36). It is even more preferable that at least one positive lens in the final lens group satisfies conditional expressions (35) and (36), and also satisfies at least one of conditional expressions (35-1), (35-2), (36-1), and (36-2).

[0157] It is preferable that the first lens group G1 includes at least one positive lens that satisfies the following conditional expression (37). Here, the refractive index of the positive lens in the first lens group G1 with respect to the d-line is defined as N1p. Ensuring that the corresponding value of conditional expression (37) is not equal to or less than the lower limit is advantageous for correcting curvature of field. Ensuring that the corresponding value of conditional expression (37) is not equal to or greater than the upper limit can prevent overcorrection of curvature of field. In order to obtain better characteristics, it is more preferable that at least one positive lens in the first lens group G1 satisfies the following conditional expression (37-1), and it is even more preferable that it satisfies the following conditional expression (37-2). 1.8<N1p<2.3 (37) 1.89<N1p<2.2 (37-1) 1.92<N1p<2.15 (37-2)

[0158] It is preferable that the first lens group G1 includes at least one positive lens that satisfies the following conditional expression (38). Here, the Abbe number of the positive lens in the first lens group G1 based on the d-line is defined as v1p. Ensuring that the corresponding value of conditional expression (38) is not equal to or less than the lower limit is advantageous for correcting lateral chromatic aberration. Ensuring that the corresponding value of conditional expression (38) is not equal to or greater than the upper limit can prevent lateral chromatic aberration from being overcorrected. In order to obtain better characteristics, it is more preferable that at least one positive lens in the first lens group G1 satisfies the following conditional expression (38-1), and it is even more preferable that it satisfies the following conditional expression (38-2). 10<v1p<45 (38) 13<v1p<35 (38-1) 16<v1p<25 (38-2)

[0159] It is preferable that at least one positive lens in the first lens group G1 satisfies conditional expressions (37) and (38). It is even more preferable that at least one positive lens in the first lens group G1 satisfies conditional expressions (37) and (38), and further satisfies at least one of conditional expressions (37-1), (37-2), (38-1), and (38-2).

[0160] It is preferable that the subsequent group GR includes an aperture stop St, and that at least one negative lens element with a concave surface facing the object side is disposed at a position closer to the image side than the aperture stop St so as to satisfy the following conditional expression (39): Here, DSInw is the axial distance between the aperture stop St and the negative lens element with a concave surface facing the object side when focused on an object at infinity at the wide-angle end. TLw is the sum of the axial distance from the lens surface of the first lens group G1 closest to the object to the lens surface of the subsequent group GR closest to the image side when focused on an object at infinity at the wide-angle end, and the back focus of the entire system in terms of air equivalent distance. An example of the distance DSInw is shown in FIG. 2. Ensuring that the value corresponding to conditional expression (39) is not below the lower limit is advantageous in ensuring space for arranging an aperture mechanism. By ensuring that the corresponding value of conditional expression (39) is not equal to or greater than the upper limit, it is possible to arrange the negative lens element with its concave surface facing the object side at a position close to the aperture stop St, which is advantageous for correcting spherical aberration and axial chromatic aberration. To obtain better characteristics, it is more preferable that the zoom lens satisfies the following conditional expression (39-1), and it is even more preferable that the zoom lens satisfies the following conditional expression (39-2): 0.001<DSInw / TLw<0.12 (39) 0.005<DSInw / TLw<0.085 (39-1) 0.01<DSInw / TLw<0.075 (39-2)

[0161] It is preferable that the subsequent group GR includes an aperture stop St, and that at least one negative lens element with a concave surface facing the image side is disposed at a position closer to the object than the aperture stop St so as to satisfy the following conditional expression (40): Here, the distance on the optical axis between the aperture stop St and the negative lens element with a concave surface facing the image side when focused on an object at infinity at the wide-angle end is designated DSOnw. An example of the distance DSOnw is shown in FIG. 2 . Ensuring that the value corresponding to conditional expression (40) is not equal to or less than the lower limit is advantageous in ensuring space for arranging an aperture mechanism. Ensuring that the value corresponding to conditional expression (40) is not equal to or greater than the upper limit is advantageous in ensuring that the negative lens element with a concave surface facing the image side is disposed close to the aperture stop St, which is advantageous in correcting spherical aberration and axial chromatic aberration. To obtain better characteristics, it is more preferable that the zoom lens element satisfies the following conditional expression (40-1), and even more preferable that the zoom lens element satisfies the following conditional expression (40-2): 0.001<DSOnw / TLw<0.18 (40) 0.01<DSOnw / TLw<0.085 (40-1) 0.03<DSOnw / TLw<0.075 (40-2)

[0162] The subsequent group GR includes an aperture stop St, and at least one cemented lens is disposed closer to the image side than the aperture stop St, and it is preferable that this cemented lens satisfy the following conditional expression (41): Here, the distance on the optical axis between the aperture stop St and the cemented surface of the cemented lens closer to the image side than the aperture stop St at the wide-angle end is defined as DSIcew. If the cemented lens has multiple cemented surfaces, it is preferable that at least one of the cemented surfaces satisfy conditional expression (41). Ensuring that the corresponding value of conditional expression (41) is not equal to or less than the lower limit is advantageous in ensuring space for arranging an aperture mechanism. Ensuring that the corresponding value of conditional expression (41) is not equal to or greater than the upper limit is advantageous in ensuring that the cemented surface can be disposed close to the aperture stop St, which is advantageous in correcting spherical aberration and axial chromatic aberration. In order to obtain better characteristics, it is more preferable that the zoom lens satisfy the following conditional expression (41-1), and it is even more preferable that the zoom lens satisfy the following conditional expression (41-2): 0.001<DSIcew / TLw<0.12 (41) 0.005<DSIcew / TLw<0.085 (41-1) 0.01<DSIcew / TLw<0.075 (41-2)

[0163] The subsequent group GR includes an aperture stop St, and at least one cemented lens is disposed closer to the object than the aperture stop St, and it is preferable that this cemented lens satisfy the following conditional expression (42): Here, the distance on the optical axis between the aperture stop St and the cemented surface of the cemented lens closer to the object than the aperture stop St at the wide-angle end is defined as DSOCew. If the cemented lens has multiple cemented surfaces, it is preferable that at least one of the cemented surfaces satisfy conditional expression (42). Ensuring that the corresponding value of conditional expression (42) is not equal to or less than the lower limit is advantageous in ensuring space for arranging an aperture mechanism. Ensuring that the corresponding value of conditional expression (42) is not equal to or greater than the upper limit is advantageous in ensuring that the cemented surface can be disposed close to the aperture stop St, which is advantageous in correcting spherical aberration and axial chromatic aberration. In order to obtain better characteristics, it is more preferable that the zoom lens satisfy the following conditional expression (42-1), and it is even more preferable that the zoom lens satisfy the following conditional expression (42-2): 0.001<DSOcew / TLw<0.18 (42) 0.01<DSOcew / TLw<0.085 (42-1) 0.03<DSOcew / TLw<0.075 (42-2)

[0164] It is preferable that the zoom lens satisfy the following conditional expression (43). Here, ΔN denotes the amount of movement of the N lens group when changing magnification from the wide-angle end to the telephoto end. ΔP denotes the amount of movement of the P lens group when changing magnification from the wide-angle end to the telephoto end. The sign of each movement amount when changing magnification is negative when moving toward the object side and positive when moving toward the image side. As an example, FIG. 2 shows the movement amount ΔN when the fourth lens group G4 corresponds to the N lens group. By ensuring that the corresponding value of conditional expression (43) is not equal to or less than the lower limit, the N lens group moves close to the P lens group near the telephoto end, which is advantageous for suppressing fluctuations in spherical aberration near the telephoto end. By ensuring that the corresponding value of conditional expression (43) is not equal to or greater than the upper limit, the N lens group moves away from the P lens group near the telephoto end, which is advantageous for suppressing fluctuations in field curvature near the telephoto end. To obtain better characteristics, it is more preferable that the zoom lens satisfies the following conditional expression (43-1), and it is even more preferable that the zoom lens satisfies the following conditional expression (43-2): 0.1<ΔN / ΔP<0.75 (43) 0.13<ΔN / ΔP<0.5 (43-1) 0.25<ΔN / ΔP<0.37 (43-2)

[0165] It is preferable that the zoom lens satisfy the following conditional expression (44). Here, Dexw is the sum of the distance on the optical axis from the paraxial exit pupil position Pexw to the lens surface of the rear group GR closest to the image when focused on an object at infinity at the wide-angle end, and the back focus of the entire system in air-equivalent distance. As an example, FIG. 2 shows the paraxial exit pupil position Pexw when focused on an object at infinity at the wide-angle end. By ensuring that the corresponding value of conditional expression (44) is not equal to or less than the lower limit, the paraxial exit pupil can be brought closer to the object side, which is advantageous for ensuring the amount of peripheral light. By ensuring that the corresponding value of conditional expression (44) is not equal to or greater than the upper limit, the paraxial exit pupil can be brought closer to the image side, which is advantageous for compactness. In order to obtain better characteristics, it is more preferable that the zoom lens satisfy the following conditional expression (44-1), and it is even more preferable that the zoom lens satisfy the following conditional expression (44-2). 1.5<Dexw / (fw×tanωw)<5 (44) 1.8<Dexw / (fw×tanωw)<4.5 (44-1) 2.2<Dexw / (fw×tanωw)<3.6 (44-2)

[0166] It is preferable that the zoom lens satisfy the following conditional expression (45). Here, Fnot is the maximum F-number when focused on an object at infinity at the telephoto end. DGP is the distance on the optical axis from the lens surface of the P lens group closest to the object to the lens surface of the P lens group closest to the image. By ensuring that the corresponding value of conditional expression (45) is not equal to or less than the lower limit, it is possible to ensure sufficient space to arrange multiple lenses in the P lens group, which is advantageous for correcting axial chromatic aberration. By ensuring that the corresponding value of conditional expression (45) is not equal to or greater than the upper limit, it is possible to reduce the thickness of the P lens group, which is advantageous for shortening the overall length of the lens system. In order to obtain better characteristics, it is more preferable that the zoom lens satisfy the following conditional expression (45-1), and it is even more preferable that the zoom lens satisfy the following conditional expression (45-2). 0.4<Fnot×DGP / ft<4 (45) 0.8<Fnot×DGP / ft<3.4 (45-1) 1.2<Fnot×DGP / ft<2 (45-2)

[0167] It is preferable that the zoom lens satisfy the following conditional expression (46). Here, Fnot is the maximum F-number when focused on an object at infinity at the telephoto end. DGP is the distance on the optical axis from the lens surface of the P lens group closest to the object to the lens surface of the P lens group closest to the image. DGM is the distance on the optical axis from the lens surface of the M lens group closest to the object to the lens surface of the M lens group closest to the image. By ensuring that the value corresponding to conditional expression (46) is not equal to or less than the lower limit, sufficient space can be secured to arrange multiple lenses in the P lens group and the M lens group, which is advantageous for correcting longitudinal chromatic aberration. By ensuring that the value corresponding to conditional expression (46) is not equal to or greater than the upper limit, the thicknesses of the P lens group and the M lens group can be reduced, which is advantageous for shortening the overall length of the lens system. In order to obtain better characteristics, it is more preferable that the zoom lens satisfy the following conditional expression (46-1), and it is even more preferable that the zoom lens satisfy the following conditional expression (46-2). 0.4<Fnot×(DGP+DGM) / ft<4 (46) 0.75<Fnot×(DGP+DGM) / ft<3.4 (46-1) 0.97<Fnot×(DGP+DGM) / ft<2.93 (46-2)

[0168] It is preferable that the zoom lens satisfy the following conditional expression (47). Here, TLt is the sum of the on-optical distance from the lens surface of the first lens group G1 closest to the object to the lens surface of the subsequent group GR closest to the image when focused on an object at infinity at the telephoto end, and the back focus of the entire system in terms of air equivalent distance. By ensuring that the value corresponding to conditional expression (47) is not equal to or less than the lower limit, it is possible to ensure space for each lens group to move during zooming, which is advantageous for achieving a high zoom ratio. By ensuring that the value corresponding to conditional expression (47) is not equal to or greater than the upper limit, it is possible to shorten the overall length of the lens system, which is advantageous for compactness. In order to obtain better characteristics, it is more preferable that the zoom lens satisfy the following conditional expression (47-1), and it is even more preferable that the zoom lens satisfy the following conditional expression (47-2). 1.2<TLt / ft<5 (47) 1.4<TLt / ft<4 (47-1) 1.66<TLt / ft<3.02 (47-2)

[0169] When the focal length of the final lens group is fE, it is preferable that the zoom lens satisfy the following conditional expression (48). Ensuring that the corresponding value of conditional expression (48) is not equal to or less than the lower limit thereof is advantageous for ensuring the back focus. Ensuring that the corresponding value of conditional expression (48) is not equal to or greater than the upper limit thereof is advantageous for shortening the overall length of the lens system. In order to obtain better characteristics, it is more preferable that the zoom lens satisfy the following conditional expressions (48-1), and it is even more preferable that the zoom lens satisfy the following conditional expressions (48-2). 0.1<fw / fE<0.7 (48) 0.17<fw / fE<0.5 (48-1) 0.25<fw / fE<0.42 (48-2)

[0170] It is preferable that the zoom lens satisfy the following conditional expression (49). Here, βfw is the lateral magnification of the focus group when focused on an object at infinity at the wide-angle end. βfRw is the combined lateral magnification of all lenses on the image side of the focus group when focused on an object at infinity at the wide-angle end. By ensuring that the corresponding value of conditional expression (49) is not equal to or less than the lower limit, the amount of movement of the focus group during focusing can be suppressed, which is advantageous for shortening the overall length of the lens system. By ensuring that the corresponding value of conditional expression (49) is not equal to or greater than the upper limit, which is advantageous for suppressing the error sensitivity of the focus group. In order to obtain better characteristics, it is more preferable that the zoom lens satisfy the following conditional expression (49-1), and it is even more preferable that the zoom lens satisfy the following conditional expression (49-2). 0.3<|(1-βfw ２ ) × βfRw ２ |<3 (49) 0.4<|(1-βfw ２ ) × βfRw ２ |<2.5 (49-1) 0.5<|(1-βfw ２ ) × βfRw ２ |<1.56 (49-2)

[0171] It is preferable that the zoom lens satisfy the following conditional expression (50). Here, the lateral magnification of the focus 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 focus group when focused on an object at infinity at the telephoto end is βfRt. By ensuring that the corresponding value of conditional expression (50) is not equal to or less than the lower limit, the amount of movement of the focus group during focusing can be suppressed, which is advantageous for shortening the overall length of the lens system. By ensuring that the corresponding value of conditional expression (50) is not equal to or greater than the upper limit, it is advantageous for suppressing the error sensitivity of the focus group. In order to obtain better characteristics, it is more preferable that the zoom lens satisfy the following conditional expression (50-1), and it is even more preferable that the zoom lens satisfy the following conditional expression (50-2). 0.5<|(1-βft ２ ) × βfRt ２ |<4 (50) 0.7<|(1-βft ２ ) × βfRt ２ |<3 (50-1) 1.2<|(1-βft ２ ) × βfRt ２ |<2.7 (50-2)

[0172] It is preferable that the zoom lens satisfy the following conditional expression (51). Here, the lateral magnification of the focus group when focused on an object at infinity at the wide-angle end is defined as βfw. The composite lateral magnification of all lenses on the image side of the focus group when focused on an object at infinity at the wide-angle end is defined as βfRw. The focal length of the focus group is defined as ffoc. The composite focal length of all lenses on the image side of the focus group when focused on an object at infinity at the wide-angle end is defined as ffRw. When focused on an object at infinity at the wide-angle end, the sum of the distance on the optical axis from the paraxial exit pupil position Pexw to the lens surface of the subsequent group closest to the image and the back focus of the entire system in air equivalent distance is defined as Dexw. Using the above symbols, γw and BRw are defined as follows: γw=(1-βfw ２ ) × βfRw ２, BRw={βfw / (ffoc×γw)-1 / (βfRw×ffRw)-(1 / Dexw)} Ensuring that the value corresponding to conditional expression (51) does not become equal to or less than the lower limit is advantageous for miniaturization. Ensuring that the value corresponding to conditional expression (51) does not become equal to or greater than the upper limit can suppress fluctuations in the angle of view when focusing at the wide-angle end. In order to obtain better characteristics, it is more preferable that the zoom lens satisfies the following conditional expression (51-1), and it is even more preferable that the zoom lens satisfies the following conditional expression (51-2). 0<(−BRw)×(fw×tanωw)<0.7 (51) 0<(−BRw)×(fw×tanωw)<0.4 (51-1) 0<(−BRw)×(fw×tanωw)<0.24 (51-2)

[0173] It is preferable that the zoom lens satisfy the following conditional expression (52). Here, the lateral magnification of the focus group when focused on an object at infinity at the telephoto end is βft. The composite lateral magnification of all lenses on the image side of the focus group when focused on an object at infinity at the telephoto end is βfRt. The focal length of the focus group is ffoc. The composite focal length of all lenses on the image side of the focus group when focused on an object at infinity at the telephoto end is ffRt. When focused on an object at infinity at the telephoto end, the sum of the distance on the optical axis from the paraxial exit pupil position to the lens surface of the subsequent group closest to the image and the back focus of the entire system in air equivalent distance is Dext. When focused on an object at infinity at the telephoto end, the maximum half angle of view when focused on an object at infinity at the telephoto end is ωt. Using the above symbols, γt and BRt are defined as follows: γt=(1-βft ２ ) × βfRt ２, BRt={βft / (ffoc×γt)-1 / (βfRt×ffRt)-(1 / Dext)} Ensuring that the value corresponding to conditional expression (52) does not become equal to or less than the lower limit is advantageous for miniaturization. Ensuring that the value corresponding to conditional expression (52) does not become equal to or greater than the upper limit can suppress fluctuations in the angle of view when focusing at the telephoto end. In order to obtain better characteristics, it is more preferable that the zoom lens satisfies the following conditional expression (52-1), and it is even more preferable that the zoom lens satisfies the following conditional expression (52-2). 0<(−BRt)×(ft×tanωt)<0.5 (52) 0<(−BRt)×(ft×tanωt)<0.3 (52-1) 0<(−BRt)×(ft×tanωt)<0.13 (52-2)

[0174] In a zoom lens configuration in which at least one of the lens closest to the object side and the lens second from the object side is a negative lens, where the refractive index of this negative lens with respect to the d-line is Nobn, it is preferable that the zoom lens satisfies the following conditional expression (53). In particular, it is preferable that the lens closest to the object side of the zoom lens is a negative lens and satisfies the following conditional expression (53). Ensuring that the corresponding value of conditional expression (53) is not equal to or less than the lower limit is advantageous for suppressing distortion and curvature of field. Ensuring that the corresponding value of conditional expression (53) is not equal to or greater than the upper limit is advantageous for suppressing lateral chromatic aberration. In order to obtain better characteristics, it is more preferable that the zoom lens satisfies the following conditional expression (53-1), and even more preferable that the zoom lens satisfies the following conditional expression (53-2): 1.7<Nobn<2.2 (53) 1.76<Nobn<2 (53-1) 1.81<Nobn<1.9 (53-2)

[0175] Of the movement loci of each lens group that moves when changing magnification from the wide-angle end to the telephoto end, there may be five different movement loci. In other words, there may be five different movement loci of each lens group that moves when changing magnification. This is advantageous for achieving a high zoom ratio while simplifying the drive mechanism.

[0176] Alternatively, among the movement loci of each lens group that moves when changing magnification from the wide-angle end to the telephoto end, the number of mutually different movement loci may be four, or may be three, which is advantageous for simplifying the drive mechanism and reducing its weight.

[0177] As in the examples described below, when there are multiple lens groups that move along the same movement locus when changing magnification from the wide-angle end to the telephoto end, the movement locus for those multiple lens groups is counted as one type. In the technology disclosed herein, if the movement loci are different from each other in a portion of the entire magnification range, they are considered to be different movement loci when changing magnification from the wide-angle end to the telephoto end, even if the movement loci are the same in other portions of the magnification range. Furthermore, the above "movement locus" naturally refers to the lens groups that move when changing magnification, and not to the lens groups that remain fixed when changing magnification.

[0178] A zoom lens may be configured to include multiple lens groups that move along the same movement locus when changing magnification from the wide-angle end to the telephoto end. In this case, the lens groups that move along the same movement locus can be driven by a single cam, thereby simplifying the lens group drive mechanism. Note that the above phrase "the same movement locus when changing magnification from the wide-angle end to the telephoto end" means that the movement locus is the same throughout the entire range of magnification from the wide-angle end to the telephoto end.

[0179] 1 is merely an example, and various modifications are possible without departing from the spirit of the technology of the present disclosure. For example, the number of lens groups included in the rear group GR and the number of lenses included in each lens group may be different from those in the example of FIG.

[0180] For example, the rear group GR may be configured to consist of three lens groups, or may be configured to consist of five lens groups, and the focus group may be configured to consist of one lens.

[0181] Furthermore, for example, one lens group may be included between the first lens group G1 and the P lens group, which is advantageous for suppressing fluctuations in distortion during zooming.

[0182] The first lens group G1 may be configured to consist, in order from the object side to the image side, of a negative lens, a negative lens, and a positive lens.The first lens group G1 may be configured to consist, in order from the object side to the image side, of a negative lens, a negative lens, a negative lens, and a positive lens.The first lens group G1 may be configured, in order from the object side to the image side, of a negative lens and a negative lens.

[0183] It is preferable that the focus group has negative refractive power. In this case, the amount of movement of the focus group during focusing can be reduced, which is advantageous for making the entire system smaller and lighter. It is preferable that the focus group includes at least one negative lens. In this case, it is advantageous for reducing fluctuations in chromatic aberration during focusing.

[0184] The focus group may be configured to consist of a single negative lens, which is advantageous for size reduction. Alternatively, the focus group may be configured to consist of a positive lens and a negative lens, which is advantageous for suppressing fluctuations in chromatic aberration during focusing.

[0185] The final lens group may be configured to include two or less lenses, which is advantageous for size reduction.

[0186] The above-described preferred and possible configurations can be arbitrarily combined, and are preferably selectively adopted as appropriate according to the required specifications. Note that the conditional expressions that the zoom lens of the present disclosure preferably satisfies are not limited to those written in the form of an equation, but include all conditional expressions obtained by arbitrarily combining lower and upper limits from among the preferred, more preferred, and even more preferred conditional expressions.

[0187] For example, a first preferred aspect of the zoom lens of the present disclosure comprises, in order from the object side to the image side, a first lens group G1 having negative refractive power and a subsequent lens group GR, the subsequent lens group GR including at least three lens groups, one of which is a P lens group having positive refractive power, the spacing between the first lens group G1 and the subsequent lens group GR changing during magnification variation, and all spacings between adjacent lens groups in the subsequent lens group GR changing, and the above conditional expressions (1) and (2) are satisfied.

[0188] A second preferred aspect of the zoom lens of the present disclosure is the first aspect described above, wherein the P lens group is the lens group in the subsequent group GR that moves the greatest amount toward the object side when changing magnification from the wide-angle end to the telephoto end, includes an N lens group having negative refractive power closer to the image side than the P lens group, and includes an M lens group between the P lens group and the N lens group, and satisfies the above conditional expression (3).

[0189] Next, examples of the zoom lens of the present disclosure will be described with reference to the drawings. Note that the reference symbols assigned to the lenses in the cross-sectional views of each example are used independently for each example to avoid cluttering the explanation and drawings due to an increase in the number of digits in the reference symbols. Therefore, even if common reference symbols are assigned in drawings of different examples, this does not necessarily mean that the configuration is the same.

[0190] [Example 1] The configuration and movement locus of a zoom lens of Example 1 are shown in Figure 1. The illustration method and configuration are as described above, so some overlapping explanations will be omitted here. The zoom lens of Example 1 comprises, in order from the object side to the image side, a first lens group G1 having negative refractive power, a second lens group G2 having positive refractive power, a third lens group G3 having positive refractive power, a fourth lens group G4 having negative refractive power, and a fifth lens group G5 having positive refractive power. The subsequent group GR comprises the second lens group G2, the third lens group G3, the fourth lens group G4, and the fifth lens group G5. During magnification change from the wide-angle end to the telephoto end, the first lens group G1, the second lens group G2, the third lens group G3, and the fourth lens group G4 move along the optical axis Z while changing the spacing between adjacent lens groups, and the fifth lens group G5 is fixed with respect to the image plane Sim. The focus group is made up of the fourth lens group G4, and when focusing from an object at infinity to the closest object, the focus group moves toward the image side.

[0191] For the zoom lens of Example 1, basic lens data is shown in Table 1, specifications and variable surface spacings are shown in Table 2, and aspherical coefficients are shown in Table 3.

[0192] The table of basic lens data is written as follows. The Sn column shows the surface numbers, with the surface closest to the object being surface number 1 and the numbers increasing by one as you move toward 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 the d-line of each component. The νd column shows the Abbe number of each component based on the d-line. The θgF column shows the partial dispersion ratio between the g-line and F-line of each component. The ED column shows the effective diameter of each surface. The SG column shows the specific gravity of each component.

[0193] In the table of basic lens data, 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. The surface number and the phrase (St) are entered in the column for the surface number corresponding to the aperture stop St. The value in the bottom column of the surface spacing column in the table is the distance between the surface closest to the image side in the table and the image plane Sim. The symbol DD[ ] is used for variable surface spacing, and the surface number on the object side of this distance is entered in the [ ] in the surface spacing column.

[0194] Table 2 shows the zoom ratio Zr, focal length f, back focal length Bf in air equivalent distance, maximum open F-number Fno., maximum full angle of view 2ω, and variable surface spacing based on the d-line. The zoom ratio is synonymous with zoom magnification. The [°] in the 2ω column indicates that the unit is degrees. In Table 2, the column labeled "Wide" shows values ​​for the wide-angle end state, the column labeled "Middle" shows values ​​for the intermediate focal length state, and the column labeled "Tele" shows values ​​for the telephoto end state.

[0195] In the basic lens data, the surface numbers of aspherical surfaces are marked with an asterisk (*), and the value of the paraxial radius of curvature is entered in the column for the radius of curvature of the aspherical surface. In Table 3, the Sn row indicates the surface numbers of aspherical surfaces, and the KA and Am rows indicate the numerical values ​​of the aspherical coefficients for each aspherical surface. Note that m in Am is an integer of 3 or more, and varies depending on the surface. For example, for the third surface in Example 1, m = 3, 4, 5, ..., 16. The numerical values ​​of the aspherical coefficients in Table 3, "E±n" (n: integer), are expressed as "×10 ±ｎ " KA and Am are aspherical coefficients in the aspherical formula expressed as follows: Zd = C × h２ / {1 + (1 - KA × C ２ ×h ２ ) １ / ２} + ΣAm × h ｍ where Zd: aspherical depth (length of perpendicular line dropped from a point on the aspherical surface at height h to a plane perpendicular to the optical axis Z where the aspherical vertex is in contact) h: height (distance from the optical axis Z to the lens surface) C: reciprocal of the paraxial radius of curvature KA, Am: aspherical coefficients, and Σ in the aspherical formula represents the summation over m.

[0196] In the data in each table, degrees are used as the unit of angle and millimeters as the unit of length, but since the optical system can be used with proportional magnification or reduction, other appropriate units can also be used. Also, in each table below, values ​​are listed rounded to a predetermined number of decimal places.

[0197]

[0198]

[0199]

[0200] FIG. 4 shows aberration diagrams of the zoom lens of Example 1 when focused on an object at infinity. From left to right, FIG. 4 shows spherical aberration, astigmatism, distortion, and lateral chromatic aberration. In FIG. 4, the upper row labeled "Wide" shows aberrations in the wide-angle end state, the middle row labeled "Middle" shows aberrations in the intermediate focal length state, and the lower row labeled "Tele" shows aberrations in the telephoto end state. In the spherical aberration diagram, aberrations at the d-line, C-line, F-line, and g-line are shown by solid lines, long-dashed lines, short-dashed lines, and dash-dot lines, respectively. In the astigmatism diagram, aberrations at the d-line in the sagittal direction are shown by solid lines, and aberrations at the d-line in the tangential direction are shown by short-dashed lines. In the distortion diagram, aberrations at the d-line are shown by solid lines. In the lateral chromatic aberration diagram, aberrations for the C-line, F-line, and g-line are shown by long-dashed lines, short-dashed lines, and dash-dot lines, 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 =.

[0201] The symbols, meanings, notation methods, and illustration methods of each data item related to the above-mentioned first embodiment are basically the same in the following embodiments unless otherwise specified, and therefore, redundant explanations will be omitted below.

[0202] [Example 2] The configuration and movement locus of a zoom lens of Example 2 are shown in Figure 5. The zoom lens of Example 2 comprises, in order from the object side to the image side, a first lens group G1 having negative refractive power, a second lens group G2 having positive refractive power, a third lens group G3 having positive refractive power, a fourth lens group G4 having negative refractive power, and a fifth lens group G5 having positive refractive power. The subsequent group GR comprises the second lens group G2, the third lens group G3, the fourth lens group G4, and the fifth lens group G5. During magnification change from the wide-angle end to the telephoto end, the first lens group G1, the second lens group G2, the third lens group G3, and the fourth lens group G4 move along the optical axis Z while changing the spacing between adjacent lens groups, while the fifth lens group G5 is fixed with respect to the image plane Sim. The focus group is made up of the fourth lens group G4, and when focusing from an object at infinity to the closest object, the focus group moves toward the image side.

[0203] The first lens group G1 consists of four lenses, L11 to L14, in order from the object side to the image side. The second lens group G2 consists of four lenses, L21 to L24, in order from the object side to the image side. The third lens group G3 consists of an aperture stop St and three lenses, L31 to L33, in order from the object side to the image side. The fourth lens group G4 consists of two lenses, L41 and L42, in order from the object side to the image side. The fifth lens group G5 consists of a single lens, L51.

[0204] For the zoom lens of Example 2, basic lens data is shown in Table 4, specifications and variable surface spacings are shown in Table 5, aspherical coefficients are shown in Table 6, and aberration diagrams are shown in FIG.

[0205]

[0206]

[0207]

[0208] [Example 3] The configuration and movement locus of the zoom lens of Example 3 are shown in Figure 7. The zoom lens of Example 3 comprises, in order from the object side to the image side, a first lens group G1 having negative refractive power, a second lens group G2 having positive refractive power, a third lens group G3 having negative refractive power, a fourth lens group G4 having negative refractive power, and a fifth lens group G5 having positive refractive power. The subsequent group GR comprises the second lens group G2, the third lens group G3, the fourth lens group G4, and the fifth lens group G5. During magnification change from the wide-angle end to the telephoto end, the first lens group G1, the second lens group G2, the third lens group G3, and the fourth lens group G4 move along the optical axis Z while changing the spacing between adjacent lens groups, while the fifth lens group G5 is fixed with respect to the image plane Sim. The focus group is made up of the fourth lens group G4, and when focusing from an object at infinity to the closest object, the focus group moves toward the image side.

[0209] The first lens group G1 consists of three lenses, L11 to L13, in order from the object side to the image side. The second lens group G2 consists of five lenses, L21 to L25, in order from the object side to the image side. The third lens group G3 consists of an aperture stop St and four lenses, L31 to L34, in order from the object side to the image side. The fourth lens group G4 consists of one lens, L41. The fifth lens group G5 consists of two lenses, L51 and L52, in order from the object side to the image side.

[0210] For the zoom lens of Example 3, basic lens data is shown in Table 7, specifications and variable surface spacings are shown in Table 8, aspherical coefficients are shown in Table 9, and aberration diagrams are shown in FIG.

[0211]

[0212]

[0213]

[0214] [Example 4] The configuration and movement locus of a zoom lens of Example 4 are shown in Figure 9. The zoom lens of Example 4 comprises, in order from the object side to the image side, a first lens group G1 having negative refractive power, a second lens group G2 having positive refractive power, a third lens group G3 having positive refractive power, a fourth lens group G4 having positive refractive power, a fifth lens group G5 having negative refractive power, and a sixth lens group G6 having positive refractive power. The subsequent group GR comprises the second lens group G2, the third lens group G3, the fourth lens group G4, the fifth lens group G5, and the sixth lens group G6. When varying the magnification from the wide-angle end to the telephoto end, the first lens group G1, the second lens group G2, the third lens group G3, the fourth lens group G4, and the fifth lens group G5 move along the optical axis Z while changing the spacing between adjacent lens groups, and the sixth lens group G6 is fixed with respect to the image plane Sim. The focus group is made up of the fifth lens group G5, and when focusing from an object at infinity to a closest object, the focus group moves toward the image side.

[0215] The first lens group G1 consists of three lenses, L11 to L13, in order from the object side to the image side. The second lens group G2 consists of four lenses, L21 to L24, in order from the object side to the image side. The third lens group G3 consists of one lens, L31. The fourth lens group G4 consists of an aperture stop St and four lenses, L41 to L44, in order from the object side to the image side. The fifth lens group G5 consists of one lens, L51. The sixth lens group G6 consists of two lenses, L61 and L62, in order from the object side to the image side.

[0216] For the zoom lens of Example 4, basic lens data is shown in Table 10, specifications and variable surface spacings are shown in Table 11, aspherical coefficients are shown in Table 12, and aberration diagrams are shown in FIG.

[0217]

[0218]

[0219]

[0220] [Example 5] The configuration and movement locus of a zoom lens of Example 5 are shown in Figure 11. The zoom lens of Example 5 comprises, in order from the object side to the image side, a first lens group G1 having negative refractive power, a second lens group G2 having positive refractive power, a third lens group G3 having positive refractive power, a fourth lens group G4 having negative refractive power, and a fifth lens group G5 having positive refractive power. The subsequent group GR comprises the second lens group G2, the third lens group G3, the fourth lens group G4, and the fifth lens group G5. When varying magnification from the wide-angle end to the telephoto end, the first lens group G1, the second lens group G2, the third lens group G3, the fourth lens group G4, and the fifth lens group G5 move along the optical axis Z while changing the spacing between adjacent lens groups. The focus group is made up of the fourth lens group G4, and when focusing from an object at infinity to the closest object, the focus group moves toward the image side.

[0221] The first lens group G1 consists of three lenses, L11 to L13, in order from the object side to the image side. The second lens group G2 consists of five lenses, L21 to L25, in order from the object side to the image side. The third lens group G3 consists of an aperture stop St and four lenses, L31 to L34, in order from the object side to the image side. The fourth lens group G4 consists of one lens, L41. The fifth lens group G5 consists of one lens, L51.

[0222] For the zoom lens of Example 5, basic lens data is shown in Table 13, specifications and variable surface spacings are shown in Table 14, aspherical coefficients are shown in Table 15, and aberration diagrams are shown in FIG.

[0223]

[0224]

[0225]

[0226] [Example 6] The configuration and movement locus of a zoom lens of Example 6 are shown in Figure 13. The zoom lens of Example 6 comprises, in order from the object side to the image side, a first lens group G1 having negative refractive power, a second lens group G2 having positive refractive power, a third lens group G3 having positive refractive power, a fourth lens group G4 having negative refractive power, and a fifth lens group G5 having positive refractive power. The subsequent group GR comprises the second lens group G2, the third lens group G3, the fourth lens group G4, and the fifth lens group G5. When varying magnification from the wide-angle end to the telephoto end, the first lens group G1, the second lens group G2, the third lens group G3, the fourth lens group G4, and the fifth lens group G5 move along the optical axis Z while changing the spacing between adjacent lens groups. The focus group is made up of the fourth lens group G4, and when focusing from an object at infinity to the closest object, the focus group moves toward the image side.

[0227] The first lens group G1 consists of three lenses, L11 to L13, in order from the object side to the image side. The second lens group G2 consists of five lenses, L21 to L25, in order from the object side to the image side. The third lens group G3 consists of an aperture stop St and four lenses, L31 to L34, in order from the object side to the image side. The fourth lens group G4 consists of one lens, L41. The fifth lens group G5 consists of one lens, L51.

[0228] For the zoom lens of Example 6, basic lens data is shown in Table 16, specifications and variable surface spacings are shown in Table 17, aspherical coefficients are shown in Table 18, and aberration diagrams are shown in FIG.

[0229]

[0230]

[0231]

[0232] [Example 7] The configuration and movement locus of the zoom lens of Example 7 are shown in Figure 15. The zoom lens of Example 7 comprises, from the object side to the image side, a first lens group G1 having negative refractive power, a second lens group G2 having positive refractive power, a third lens group G3 having positive refractive power, and a fourth lens group G4 having negative refractive power. The trailing lens group GR comprises the second lens group G2, the third lens group G3, and the fourth lens group G4. When varying the magnification from the wide-angle end to the telephoto end, the first lens group G1, the second lens group G2, the third lens group G3, and the fourth lens group G4 move along the optical axis Z while changing the spacing between adjacent lens groups. The focus group comprises the fourth lens group G4, and when focusing from an object at infinity to a closest object, the focus group moves toward the image side.

[0233] The first lens group G1 consists of three lenses, L11 to L13, from the object side to the image side. The second lens group G2 consists of five lenses, L21 to L25, from the object side to the image side. The third lens group G3 consists of an aperture stop St and four lenses, L31 to L34, from the object side to the image side. The fourth lens group G4 consists of two lenses, L41 to L42, from the object side to the image side.

[0234] For the zoom lens of Example 7, basic lens data is shown in Table 19, specifications and variable surface spacings are shown in Table 20, aspherical coefficients are shown in Table 21, and aberration diagrams are shown in FIG.

[0235]

[0236]

[0237]

[0238] [Example 8] The configuration and movement locus of a zoom lens of Example 8 are shown in Figure 17. The zoom lens of Example 8 comprises, in order from the object side to the image side, a first lens group G1 having negative refractive power, a second lens group G2 having positive refractive power, a third lens group G3 having positive refractive power, a fourth lens group G4 having positive refractive power, a fifth lens group G5 having negative refractive power, and a sixth lens group G6 having positive refractive power. The subsequent group GR comprises the second lens group G2, the third lens group G3, the fourth lens group G4, the fifth lens group G5, and the sixth lens group G6. When varying magnification from the wide-angle end to the telephoto end, the first lens group G1, the second lens group G2, the third lens group G3, the fourth lens group G4, and the fifth lens group G5 move along the optical axis Z while changing the spacing between adjacent lens groups, and the sixth lens group G6 is fixed with respect to the image plane Sim. When varying magnification from the wide-angle end to the telephoto end, the second lens group G2 and the fourth lens group G4 move along the optical axis Z on the same movement locus. The focus group is made up of the fifth lens group G5, and when focusing from an object at infinity to a closest object, the focus group moves toward the image side.

[0239] The first lens group G1 consists of three lenses, L11 to L13, in order from the object side to the image side. The second lens group G2 consists of three lenses, L21 to L23, in order from the object side to the image side. The third lens group G3 consists of one lens, L31. The fourth lens group G4 consists of an aperture stop St and four lenses, L41 to L44, in order from the object side to the image side. The fifth lens group G5 consists of one lens, L51. The sixth lens group G6 consists of two lenses, L61 and L62, in order from the object side to the image side.

[0240] For the zoom lens of Example 8, basic lens data is shown in Table 22, specifications and variable surface spacings are shown in Table 23, aspherical coefficients are shown in Table 24, and aberration diagrams are shown in FIG.

[0241]

[0242]

[0243]

[0244] Example 9 The configuration and movement locus of a zoom lens of Example 9 are shown in Figure 19. The zoom lens of Example 9 comprises, in order from the object side to the image side, a first lens group G1 having negative refractive power, a second lens group G2 having positive refractive power, a third lens group G3 having positive refractive power, a fourth lens group G4 having negative refractive power, and a fifth lens group G5 having positive refractive power. The subsequent group GR comprises the second lens group G2, the third lens group G3, the fourth lens group G4, and the fifth lens group G5. During magnification change from the wide-angle end to the telephoto end, the first lens group G1, the second lens group G2, the third lens group G3, and the fourth lens group G4 move along the optical axis Z while changing the spacing between adjacent lens groups, while the fifth lens group G5 is fixed with respect to the image plane Sim. The focus group is made up of the fourth lens group G4, and when focusing from an object at infinity to the closest object, the focus group moves toward the image side.

[0245] The first lens group G1 consists of three lenses, L11 to L13, in order from the object side to the image side. The second lens group G2 consists of four lenses, L21 to L24, in order from the object side to the image side. The third lens group G3 consists of an aperture stop St and three lenses, L31 to L33, in order from the object side to the image side. The fourth lens group G4 consists of two lenses, L41 and L42, in order from the object side to the image side. The fifth lens group G5 consists of a single lens, L51.

[0246] For the zoom lens of Example 9, basic lens data is shown in Table 25, specifications and variable surface spacing are shown in Table 26, aspherical coefficients are shown in Table 27, and aberration diagrams are shown in FIG.

[0247]

[0248]

[0249]

[0250] [Example 10] The configuration and movement locus of the zoom lens of Example 10 are shown in Figure 21. The zoom lens of Example 10 consists, in order from the object side to the image side, of a first lens group G1 having negative refractive power, a second lens group G2 having positive refractive power, a third lens group G3 having positive refractive power, and a fourth lens group G4 having negative refractive power. The trailing group GR consists of the second lens group G2, the third lens group G3, and the fourth lens group G4. When varying magnification from the wide-angle end to the telephoto end, the first lens group G1, the second lens group G2, the third lens group G3, and the fourth lens group G4 move along the optical axis Z while changing the spacing between adjacent lens groups. The focus group consists of the fourth lens group G4, and when focusing from an object at infinity to a closest object, the focus group moves toward the image side.

[0251] The first lens group G1 consists of three lenses, L11 to L13, from the object side to the image side. The second lens group G2 consists of five lenses, L21 to L25, from the object side to the image side. The third lens group G3 consists of an aperture stop St and four lenses, L31 to L34, from the object side to the image side. The fourth lens group G4 consists of two lenses, L41 to L42, from the object side to the image side.

[0252] For the zoom lens of Example 10, basic lens data is shown in Table 28, specifications and variable surface spacings are shown in Table 29, aspherical coefficients are shown in Table 30, and aberration diagrams are shown in FIG.

[0253]

[0254]

[0255]

[0256] Example 11 The configuration and movement locus of a zoom lens of Example 11 are shown in Figure 23. The zoom lens of Example 11 comprises, in order from the object side to the image side, a first lens group G1 having negative refractive power, a second lens group G2 having positive refractive power, a third lens group G3 having positive refractive power, a fourth lens group G4 having negative refractive power, and a fifth lens group G5 having positive refractive power. The subsequent group GR comprises the second lens group G2, the third lens group G3, the fourth lens group G4, and the fifth lens group G5. During zooming from the wide-angle end to the telephoto end, the first lens group G1, the second lens group G2, the third lens group G3, and the fourth lens group G4 move along the optical axis Z while changing the spacing between adjacent lens groups, and the fifth lens group G5 is fixed with respect to the image plane Sim. The focus group is made up of the fourth lens group G4, and when focusing from an object at infinity to the closest object, the focus group moves toward the image side.

[0257] The first lens group G1 consists of three lenses, L11 to L13, in order from the object side to the image side. The second lens group G2 consists of four lenses, L21 to L24, in order from the object side to the image side. The third lens group G3 consists of an aperture stop St and three lenses, L31 to L33, in order from the object side to the image side. The fourth lens group G4 consists of two lenses, L41 and L42, in order from the object side to the image side. The fifth lens group G5 consists of a single lens, L51.

[0258] For the zoom lens of Example 11, basic lens data is shown in Table 31, specifications and variable surface spacings are shown in Table 32, aspherical coefficients are shown in Table 33, and aberration diagrams are shown in FIG.

[0259]

[0260]

[0261]

[0262] [Example 12] The configuration and movement locus of a zoom lens of Example 12 are shown in Figure 25. The zoom lens of Example 12 comprises, in order from the object side to the image side, a first lens group G1 having negative refractive power, a second lens group G2 having negative refractive power, a third lens group G3 having positive refractive power, a fourth lens group G4 having positive refractive power, a fifth lens group G5 having negative refractive power, and a sixth lens group G6 having positive refractive power. The subsequent group GR comprises the second lens group G2, the third lens group G3, the fourth lens group G4, the fifth lens group G5, and the sixth lens group G6. When varying the magnification from the wide-angle end to the telephoto end, the first lens group G1, the second lens group G2, the third lens group G3, the fourth lens group G4, and the fifth lens group G5 move along the optical axis Z while changing the spacing between adjacent lens groups, and the sixth lens group G6 is fixed with respect to the image plane Sim. The focus group is made up of the fifth lens group G5, and when focusing from an object at infinity to a closest object, the focus group moves toward the image side.

[0263] The first lens group G1 consists of, in order from the object side to the image side, two lenses, L11 and L12. The second lens group G2 consists of, in order from the object side to the image side, two lenses, L21 and L22. The third lens group G3 consists of, in order from the object side to the image side, three lenses, L31 to L33. The fourth lens group G4 consists of, in order from the object side to the image side, an aperture stop St and three lenses, L41 to L43. The fifth lens group G5 consists of, in order from the object side to the image side, two lenses, L51 and L52. The sixth lens group G6 consists of a single lens, lens L61.

[0264] For the zoom lens of Example 12, basic lens data is shown in Table 34, specifications and variable surface spacings are shown in Table 35, aspherical coefficients are shown in Table 36, and aberration diagrams are shown in FIG.

[0265]

[0266]

[0267]

[0268] [Example 13] The configuration and movement locus of the zoom lens of Example 13 are shown in Figure 27. The zoom lens of Example 13 comprises, from the object side to the image side, a first lens group G1 having negative refractive power, a second lens group G2 having positive refractive power, a third lens group G3 having negative refractive power, and a fourth lens group G4 having positive refractive power. The trailing lens group GR comprises the second lens group G2, the third lens group G3, and the fourth lens group G4. When varying the magnification from the wide-angle end to the telephoto end, the first lens group G1, the second lens group G2, and the third lens group G3 move along the optical axis Z while changing the spacing between adjacent lens groups, and the fourth lens group G4 is fixed with respect to the image plane Sim. The focus group comprises the third lens group G3, and when focusing from an object at infinity to a closest object, the focus group moves toward the image side.

[0269] The first lens group G1 consists of three lenses, L11 to L13, in order from the object side to the image side. The second lens group G2 consists of an aperture stop St and six lenses, L21 to L26. The third lens group G3 consists of one lens, L31. The fourth lens group G4 consists of one lens, L41.

[0270] For the zoom lens of Example 13, basic lens data is shown in Table 37, specifications and variable surface spacings are shown in Table 38, aspherical coefficients are shown in Table 39, and various aberration diagrams are shown in FIG.

[0271]

[0272]

[0273]

[0274] [Example 14] The configuration and movement locus of the zoom lens of Example 14 are shown in Figure 29. The zoom lens of Example 14 comprises, from the object side to the image side, a first lens group G1 having negative refractive power, a second lens group G2 having positive refractive power, a third lens group G3 having negative refractive power, and a fourth lens group G4 having positive refractive power. The trailing lens group GR comprises the second lens group G2, the third lens group G3, and the fourth lens group G4. When varying the magnification from the wide-angle end to the telephoto end, the first lens group G1, the second lens group G2, and the third lens group G3 move along the optical axis Z while changing the spacing between adjacent lens groups, and the fourth lens group G4 is fixed with respect to the image plane Sim. The focus group comprises the third lens group G3, and when focusing from an object at infinity to a closest object, the focus group moves toward the image side.

[0275] The first lens group G1 consists of three lenses, L11 to L13, in order from the object side to the image side. The second lens group G2 consists of an aperture stop St and six lenses, L21 to L26. The third lens group G3 consists of one lens, L31. The fourth lens group G4 consists of one lens, L41.

[0276] For the zoom lens of Example 14, basic lens data is shown in Table 40, specifications and variable surface spacings are shown in Table 41, aspherical coefficients are shown in Table 42, and various aberration diagrams are shown in FIG.

[0277]

[0278]

[0279]

[0280] [Example 15] The configuration and movement locus of the zoom lens of Example 15 are shown in Figure 31. The zoom lens of Example 15 comprises, from the object side to the image side, a first lens group G1 having negative refractive power, a second lens group G2 having positive refractive power, a third lens group G3 having negative refractive power, and a fourth lens group G4 having positive refractive power. The trailing lens group GR comprises the second lens group G2, the third lens group G3, and the fourth lens group G4. When varying the magnification from the wide-angle end to the telephoto end, the first lens group G1, the second lens group G2, and the third lens group G3 move along the optical axis Z while changing the spacing between adjacent lens groups, and the fourth lens group G4 is fixed with respect to the image plane Sim. The focus group comprises the third lens group G3, and when focusing from an object at infinity to a closest object, the focus group moves toward the image side.

[0281] The first lens group G1 consists of three lenses, L11 to L13, in order from the object side to the image side. The second lens group G2 consists of an aperture stop St and six lenses, L21 to L26. The third lens group G3 consists of one lens, L31. The fourth lens group G4 consists of one lens, L41.

[0282] For the zoom lens of Example 15, basic lens data is shown in Table 43, specifications and variable surface spacings are shown in Table 44, aspherical coefficients are shown in Table 45, and aberration diagrams are shown in FIG.

[0283]

[0284]

[0285]

[0286] [Example 16] The configuration and movement locus of the zoom lens of Example 16 are shown in Figure 33. The zoom lens of Example 16 comprises, from the object side to the image side, a first lens group G1 having negative refractive power, a second lens group G2 having positive refractive power, a third lens group G3 having negative refractive power, and a fourth lens group G4 having positive refractive power. The trailing lens group GR comprises the second lens group G2, the third lens group G3, and the fourth lens group G4. When varying the magnification from the wide-angle end to the telephoto end, the first lens group G1, the second lens group G2, and the third lens group G3 move along the optical axis Z while changing the spacing between adjacent lens groups, and the fourth lens group G4 is fixed with respect to the image plane Sim. The focus group comprises the third lens group G3, and when focusing from an object at infinity to a closest object, the focus group moves toward the image side.

[0287] The first lens group G1 consists of three lenses, L11 to L13, in order from the object side to the image side. The second lens group G2 consists of an aperture stop St and six lenses, L21 to L26. The third lens group G3 consists of one lens, L31. The fourth lens group G4 consists of one lens, L41.

[0288] For the zoom lens of Example 16, basic lens data is shown in Table 46, specifications and variable surface spacings are shown in Table 47, aspherical coefficients are shown in Table 48, and aberration diagrams are shown in FIG.

[0289]

[0290]

[0291]

[0292] [Example 17] The configuration and movement locus of the zoom lens of Example 17 are shown in Figure 35. The zoom lens of Example 17 comprises, from the object side to the image side, a first lens group G1 having negative refractive power, a second lens group G2 having positive refractive power, a third lens group G3 having negative refractive power, and a fourth lens group G4 having positive refractive power. The trailing lens group GR comprises the second lens group G2, the third lens group G3, and the fourth lens group G4. When varying the magnification from the wide-angle end to the telephoto end, the first lens group G1, the second lens group G2, and the third lens group G3 move along the optical axis Z while changing the spacing between adjacent lens groups, and the fourth lens group G4 is fixed with respect to the image plane Sim. The focus group comprises the third lens group G3, and when focusing from an object at infinity to a closest object, the focus group moves toward the image side.

[0293] The first lens group G1 consists of three lenses, L11 to L13, in order from the object side to the image side. The second lens group G2 consists of an aperture stop St and six lenses, L21 to L26. The third lens group G3 consists of one lens, L31. The fourth lens group G4 consists of one lens, L41.

[0294] For the zoom lens of Example 17, basic lens data is shown in Table 49, specifications and variable surface spacings are shown in Table 50, aspherical coefficients are shown in Table 51, and various aberration diagrams are shown in FIG.

[0295]

[0296]

[0297]

[0298] [Example 18] The configuration and movement locus of a zoom lens of Example 18 are shown in Figure 37. The zoom lens of Example 18 comprises, in order from the object side to the image side, a first lens group G1 having negative refractive power, a second lens group G2 having positive refractive power, a third lens group G3 having positive refractive power, a fourth lens group G4 having negative refractive power, and a fifth lens group G5 having positive refractive power. The subsequent group GR comprises the second lens group G2, the third lens group G3, the fourth lens group G4, and the fifth lens group G5. During zooming from the wide-angle end to the telephoto end, the first lens group G1, the second lens group G2, the third lens group G3, and the fourth lens group G4 move along the optical axis Z while changing the spacing between adjacent lens groups, and the fifth lens group G5 is fixed with respect to the image plane Sim. The focus group is made up of the fourth lens group G4, and when focusing from an object at infinity to the closest object, the focus group moves toward the image side.

[0299] The first lens group G1 consists of four lenses, L11 to L14, in order from the object side to the image side. The second lens group G2 consists of three lenses, L21 to L23, in order from the object side to the image side. The third lens group G3 consists of an aperture stop St and five lenses, L31 to L35, in order from the object side to the image side. The fourth lens group G4 consists of three lenses, L41 to L43, in order from the object side to the image side. The fifth lens group G5 consists of a single lens, L51.

[0300] For the zoom lens of Example 18, basic lens data is shown in Table 52, specifications and variable surface spacings are shown in Table 53, aspherical coefficients are shown in Table 54, and various aberration diagrams are shown in FIG.

[0301]

[0302]

[0303]

[0304] Example 19 The configuration and movement locus of a zoom lens of Example 19 are shown in Figure 39. The zoom lens of Example 19 comprises, in order from the object side to the image side, a first lens group G1 having negative refractive power, a second lens group G2 having positive refractive power, a third lens group G3 having positive refractive power, a fourth lens group G4 having negative refractive power, and a fifth lens group G5 having positive refractive power. The rear group GR comprises the second lens group G2, the third lens group G3, the fourth lens group G4, and the fifth lens group G5. During zooming from the wide-angle end to the telephoto end, the first lens group G1, the second lens group G2, the third lens group G3, and the fourth lens group G4 move along the optical axis Z while changing the spacing between adjacent lens groups, and the fifth lens group G5 is fixed with respect to the image plane Sim. The focus group is made up of the fourth lens group G4, and when focusing from an object at infinity to the closest object, the focus group moves toward the image side.

[0305] The first lens group G1 consists of four lenses, L11 to L14, in order from the object side to the image side. The second lens group G2 consists of three lenses, L21 to L23, in order from the object side to the image side. The third lens group G3 consists of an aperture stop St and five lenses, L31 to L35, in order from the object side to the image side. The fourth lens group G4 consists of three lenses, L41 to L43, in order from the object side to the image side. The fifth lens group G5 consists of a single lens, L51.

[0306] For the zoom lens of Example 19, basic lens data is shown in Table 55, specifications and variable surface spacings are shown in Table 56, aspherical coefficients are shown in Table 57, and various aberration diagrams are shown in FIG.

[0307]

[0308]

[0309]

[0310] Tables 58 to 65 show values ​​corresponding to conditional expressions (1) to (53) for the zoom lenses of Examples 1 to 19. A conditional expression may take multiple values, but Tables 58 to 65 show only one representative value. The values ​​corresponding to the Examples shown in Tables 58 to 65 may be used as upper or lower limits for the conditional expressions to set preferred ranges for the conditional expressions.

[0311]

[0312]

[0313]

[0314]

[0315]

[0316]

[0317]

[0318]

[0319] Next, an imaging device according to an embodiment of the present disclosure will be described. Figures 41 and 42 show external views of a camera 30, which is an imaging device according to an embodiment of the present disclosure. Figure 41 shows a perspective view of the camera 30 as seen from the front side, and Figure 42 shows a perspective view of the camera 30 as seen from the rear side. The camera 30 is a so-called mirrorless 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.

[0320] The camera 30 has a camera body 31, and 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 ​​can display a captured image and an image within the angle of view before the image was captured.

[0321] A photographic opening through which light from a subject to be photographed enters is provided in the center of the front face of the camera body 31, and a mount 37 is provided at a position corresponding to the photographic opening, and an interchangeable lens 20 is attached to the camera body 31 via the mount 37.

[0322] The camera body 31 contains an imaging element such as a CCD (Charge Coupled Device) or CMOS (Complementary Metal Oxide Semiconductor) that outputs an imaging signal corresponding to the subject image formed by the interchangeable lens 20, a signal processing circuit that processes the imaging signal output from the imaging element to generate an image, and a recording medium for recording the generated image. The camera 30 is capable of taking still images or videos by pressing the shutter button 32, and the image data obtained by this shooting is recorded on the recording medium.

[0323] Although the technology of the present disclosure has been described above using embodiments and examples, the technology of the present disclosure is not limited to the above embodiments and examples and can be modified in various ways. For example, the radius of curvature, surface spacing, refractive index, Abbe number, aspherical coefficient, etc. of each lens are not limited to the values ​​shown in the above examples and can take other values.

[0324] 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.

[0325] The following supplementary items are further disclosed regarding the above embodiments and examples. [Additional Item 1] The lens system comprises, in order from the object side to the image side, a first lens group having negative refractive power and a subsequent lens group, wherein the subsequent lens group includes at least three lens groups, one of the at least three lens groups is a P lens group having positive refractive power, and when varying magnification, the distance between the first lens group and the subsequent lens group changes, and all distances between adjacent lens groups in the subsequent lens group change, and where fw is the focal length of the entire system when focused on an object at infinity at the wide-angle end, ft is the focal length of the entire system when focused on an object at infinity at the telephoto end, Bfw is the back focus of the entire system in air-equivalent distance when focused on an object at infinity at the wide-angle end, and ωw is the maximum half angle of view when focused on an object at infinity at the wide-angle end, the following relationships hold: 1.5<ft / fw<6 (1) 0.4<Bfw / (fw×tanωw)<2 (2) A zoom lens that satisfies conditional expressions (1) and (2) expressed by the following expression. [Addendum 2] The zoom lens according to Addendum 1, wherein the P lens group is the lens group in the subsequent group that moves the greatest amount toward the object side when varying magnification from the wide-angle end to the telephoto end. [Addendum 3] The zoom lens according to Addendum 2, wherein, where ΔP is the amount of movement of the P lens group when varying magnification from the wide-angle end to the telephoto end, and the sign of the amount of movement when varying magnification is negative when moving toward the object side and positive when moving toward the image side, the zoom lens satisfies conditional expression (3) expressed by the following expression: 0.9<(-ΔP) / fw<6 (3) [Addendum 4] The zoom lens according to Addendum 2, which includes an N lens group having negative refractive power located closer to the image than the P lens group. [Addendum 5] The zoom lens according to Addendum 4, which includes, closer to the image than the N lens group, a final lens group that is located closest to the image within the zoom lens. [Supplementary Item 6] The zoom lens according to Supplementary Item 4 or 5, wherein at least a portion of the N lens group is a focus group that moves along the optical axis during focusing. [Supplementary Item 7] The zoom lens according to any one of Supplementary Items 4 to 6, wherein, where fN is the focal length of the N lens group, the zoom lens satisfies conditional expression (4) expressed as: 0.5<(-fN) / fw<7 (4).[Addendum 8] The zoom lens according to any one of Addendums 1 to 7, satisfying conditional expression (5) expressed as follows: 1.2<Fnot<5.8 (5) where Fnot is the maximum F-number when focused on an object at infinity at the telephoto end. [Addendum 9] The zoom lens according to any one of Addendums 1 to 8, satisfying conditional expression (6) expressed as follows: 0.95<Fnot / Fnow<1.8 (6) where Fnot is the maximum F-number when focused on an object at infinity at the telephoto end, and Fnow is the maximum F-number when focused on an object at infinity at the wide-angle end. [Addendum 10] The zoom lens according to any one of Addendums 2 to 7, satisfying conditional expression (7) expressed as follows: 0.5<fP / fw<6 (7) where fP is the focal length of the P lens group. [Addendum 11] The zoom lens according to any one of Addendums 1 to 10, which satisfies conditional expression (8) expressed as follows: 35<ωw<54 (8) [Addendum 12] The zoom lens according to Addendum 5, wherein the final lens group has positive refractive power. [Addendum 13] The zoom lens according to any one of Addendums 4 to 7, which includes an M lens group between the P lens group and the N lens group. [Addendum 14] The zoom lens according to any one of Addendums 1 to 13, wherein the P lens group is the lens group in the subsequent group that moves the greatest amount toward the object side when varying magnification from the wide-angle end to the telephoto end, includes an N lens group that has negative refractive power on the image side of the P lens group, and includes an M lens group between the P lens group and the N lens group, and satisfies conditional expression (3) expressed as follows: 0.9<(-ΔP) / fw<6 (3) [Addendum 15] The zoom lens according to Addendum 13 or 14, wherein the M lens group has positive refractive power. [Supplementary Item 16] The zoom lens according to any one of Supplementary Items 13 to 15, which satisfies conditional expression (9) expressed as follows: 0.01<fw / fM<0.35 (9) where fM is the focal length of the M lens group.[Addendum 17] A zoom lens according to any one of Addendums 13 to 16, satisfying conditional expressions (10) and (11) expressed by the following: 1.73<NMp<2.5 (10) 10<νMp<50 (11) where NMp is the refractive index for the d-line of the positive lens closest to the image among the positive lenses in the M lens group, and νMp is the Abbe number based on the d-line of the positive lens closest to the image among the positive lenses in the M lens group. [Addendum 18] A zoom lens according to any one of Addendums 13 to 17, including an aperture stop closest to the object side of the M lens group. [Addendum 19] A zoom lens according to any one of Addendums 1 to 18, wherein the first lens group includes, closest to the object, a negative meniscus lens with a concave surface facing the image side. [Addendum 20] The zoom lens according to any one of Addendums 1 to 19, satisfying conditional expression (12) expressed by: 1<(-f1) / fw<2.5 (12) where f1 is the focal length of the first lens group. [Addendum 21] The zoom lens according to any one of Addendums 1 to 20, satisfying conditional expression (13) expressed by: 0.71<DG1 / (fw×tanωw)<2.5 (13) where DG1 is the distance on the optical axis from the lens surface of the first lens group closest to the object to the lens surface of the first lens group closest to the image. [Addendum 22] The zoom lens according to any one of Addendums 2 to 7, satisfying conditional expression (14) expressed by: 0.35<DGP / (fw×tan ωw)<2.5 (14), where DGP is the distance on the optical axis from the lens surface of the P lens group closest to the object to the lens surface of the P lens group closest to the image. [Addendum 23] The zoom lens according to any one of Addendums 1 to 22, satisfying conditional expression (15) expressed by: 1<Denw / fw<2.2 (15), where Denw is the distance on the optical axis from the lens surface of the first lens group closest to the object to the paraxial entrance pupil position when focused on an object at infinity at the wide-angle end. [Addendum 24] The zoom lens according to any one of Addendums 1 to 23, satisfying conditional expression (16) expressed as: 1<G1ave<5 (16) where G1ave is the average value of the specific gravities of all the lenses in the first lens group.[Addendum 25] The zoom lens according to any one of Addendums 2 to 7, satisfying conditional expression (17) expressed by: 1<GPave<5 (17) where GPave is the average value of the specific gravities of all lenses in the P lens group. [Addendum 26] The zoom lens according to Addendum 6, satisfying conditional expression (18) expressed by: 0.03<Gfave×DGfoc / |ffoc|<0.9 (18) where GPave is the average value of the specific gravities of all lenses in the focus group, DGfoc is the distance on the optical axis from the lens surface of the focus group closest to the object to the lens surface of the focus group closest to the image, and ffoc is the focal length of the focus group. [Addendum 27] ​​The zoom lens according to any one of Addendums 2 to 7, satisfying conditional expression (19) expressed by: 0.3<(-f1) / fP<1.5 (19) where f1 is the focal length of the first lens group and fP is the focal length of the P lens group. [Addendum 28] The zoom lens according to any one of Addendums 13 to 18, satisfying conditional expression (20) expressed by: 0<(-f1) / fM<0.7 (20) where f1 is the focal length of the first lens group and fM is the focal length of the M lens group. [Addendum 29] The zoom lens according to any one of Addendums 13 to 18, satisfying conditional expression (21) expressed by: 0<fP / fM<2 (21) where fP is the focal length of the P lens group and fM is the focal length of the M lens group. [Addendum 30] The zoom lens according to Addendum 6, which satisfies the following conditional expression (22): 1.2<(-ffoc) / (fw×tan ωw)<5.5 (22) where ffoc is the focal length of the focus group.[Additional Item 31] The zoom lens according to any one of Additional Items 1 to 30, wherein the first lens group includes at least one aspherical lens, and satisfies conditional expression (23) expressed by: 1.05<(1 / Rc1f-1 / Rc1r) / (1 / Ry1f-1 / Ry1r)<8 (23) where Rc1f is a paraxial radius of curvature of an object-side surface of the aspherical lens in the first lens group, Rc1r is a paraxial radius of curvature of an image-side surface of the aspherical lens in the first lens group, Ry1f is a radius of curvature at a position of maximum effective diameter of the object-side surface of the aspherical lens in the first lens group, and Ry1r is a radius of curvature at a position of maximum effective diameter of the image-side surface of the aspherical lens in the first lens group. [Additional Item 32] The zoom lens according to any one of Additional Items 2 to 7, wherein the P lens group includes at least one aspherical lens, and satisfies conditional expression (24) expressed by the following formula: 0.01<(1 / RcPf-1 / RyPf)×NP×fP<5 (24) where RcPf is the paraxial radius of curvature of the object-side surface of the aspherical lens in the P lens group, RyPf is the radius of curvature of the object-side surface of the aspherical lens in the P lens group at the position of the maximum effective diameter, NP is the refractive index of the aspherical lens in the P lens group with respect to the d-line, and fP is the focal length of the P lens group. [Additional Item 33] The zoom lens according to any one of Additional Items 4 to 7, wherein the N lens group includes at least one aspherical lens, and satisfies conditional expression (25) expressed by: 0.7<(1 / RcNf-1 / RcNr) / (1 / RyNf-1 / RyNr)<0.996 (25), where RcNf is a paraxial radius of curvature of the object-side surface of the aspherical lens in the N lens group, RcNr is a paraxial radius of curvature of the image-side surface of the aspherical lens in the N lens group, RyNf is a radius of curvature of the object-side surface of the aspherical lens in the N lens group at the position of maximum effective diameter, and RyNr is a radius of curvature of the image-side surface of the aspherical lens in the N lens group at the position of maximum effective diameter.[Addendum 34] The zoom lens according to Addendum 5, wherein the final lens group includes at least one aspherical lens, and satisfies conditional expression (26) expressed by: 1.01<(1 / RcEf-1 / RcEr) / (1 / RyEf-1 / RyEr)<2 (26) where RcEf is the paraxial radius of curvature of the object-side surface of the aspherical lens in the final lens group, RcEr is the paraxial radius of curvature of the image-side surface of the aspherical lens in the final lens group, RyEf is the radius of curvature at the position of maximum effective diameter of the object-side surface of the aspherical lens in the final lens group, and RyEr is the radius of curvature at the position of maximum effective diameter of the image-side surface of the aspherical lens in the N lens group. [Addendum 35] The zoom lens according to any one of Addendums 1 to 34, wherein the first lens group includes at least one negative lens, and satisfies conditional expressions (27) and (28) expressed by the following expressions: 55<ν1n<110 (27) 0.003<θgF1n−(0.6438−0.001682×ν1n)<0.05 (28) where ν1n is the Abbe number based on the d-line of the negative lens in the first lens group, and θgF1n is the partial dispersion ratio between the g-line and the F-line of the negative lens in the first lens group. [Addendum 36] The zoom lens according to any one of Addendums 2 to 7, wherein the P lens group includes at least one negative lens, and satisfies conditional expressions (29) and (30) expressed by the following: 55<νPn<110 (29) 0.003<θgFPn−(0.6438−0.001682×νPn)<0.05 (30) where νPn is the Abbe number based on the d-line of the negative lens in the P lens group, and θgFPn is the partial dispersion ratio between the g-line and the F-line of the negative lens in the P lens group. [Addendum 37] The zoom lens according to any one of Addendums 4 to 7, wherein the N lens group includes at least one negative lens, and satisfies conditional expressions (31) and (32) expressed by the following: 55<νNn<110 (31) 0.003<θgFNn−(0.6438−0.001682×νNn)<0.05 (32) where νNn is the Abbe number of the negative lens in the N lens group based on the d-line, and θgFNn is the partial dispersion ratio between the g-line and the F-line of the negative lens in the N lens group.[Addendum 38] The zoom lens according to any one of Addendums 13 to 18, wherein the M lens group includes at least one negative lens, and satisfies conditional expressions (33) and (34) expressed by the following: 55<νMn<110 (33) 0.003<θgFMn−(0.6438−0.001682×νMn)<0.06 (34) where νMn is the Abbe number based on the d-line of the negative lens in the M lens group, and θgFMn is the partial dispersion ratio between the g-line and the F-line of the negative lens in the M lens group. [Addendum 39] The zoom lens according to Addendum 5, wherein the final lens group includes at least one positive lens, and satisfies conditional expressions (35) and (36) expressed by the following expressions: 55<νEp<110 (35) 0.003<θgFEp−(0.6438−0.001682×νEp)<0.05 (36) where νEp is the Abbe number of the positive lens in the final lens group based on the d-line, and θgFEp is the partial dispersion ratio between the g-line and the F-line of the positive lens in the final lens group. [Addendum 40] The zoom lens according to any one of Addendum 1 to 39, wherein the first lens group includes at least one positive lens, and where N1p is the refractive index of the positive lens in the first lens group with respect to the d-line and v1p is the Abbe number of the positive lens in the first lens group with respect to the d-line, the zoom lens satisfies conditional expressions (37) and (38) expressed by the following: 1.8<N1p<2.3 (37) 10<v1p<45 (38) [Addendum 41] The zoom lens according to Addendum 5, wherein the final lens group is fixed with respect to the image plane during zooming. [Addendum 42] The zoom lens according to Addendum 19, wherein the first lens group includes a biconcave lens arranged closer to the image side than the negative meniscus lens, and a positive lens arranged closer to the image side than the biconcave lens. [Addendum 43] The zoom lens according to any one of Addendums 1 to 42, wherein the first lens group at the telephoto end is located closer to the image side than the first lens group at the wide-angle end. [Addendum 44] The zoom lens according to any one of Addendums 1 to 42, wherein the first lens group at the telephoto end is located closer to the object side than the first lens group at the wide-angle end.[Additional Item 45] The zoom lens according to any one of Additional Items 1 to 44, wherein the subsequent group includes an aperture stop, and at least one negative lens with a concave surface facing the object side is disposed closer to the image side than the aperture stop, and satisfies conditional expression (39) expressed by 0.001<DSInw / TLw<0.12 (39), where DSInw is the distance on the optical axis between the aperture stop and the negative lens with its concave surface facing the object side when focused on an object at infinity at the wide-angle end, and TLw is the sum of the distance on the optical axis from the lens surface of the first lens group closest to the object to the lens surface of the subsequent group closest to the image when focused on an object at infinity at the wide-angle end, and the back focus of the entire system in terms of an air-equivalent distance. [Additional Item 46] The zoom lens according to any one of Additional Items 1 to 45, wherein the subsequent group includes an aperture stop, and at least one negative lens with a concave surface facing the image side is arranged closer to the object than the aperture stop, and the zoom lens satisfies conditional expression (40) expressed by 0.001<DSOnw / TLw<0.18 (40), where DSOnw is the distance on the optical axis between the aperture stop and the negative lens with its concave surface facing the image side when focused on an object at infinity at the wide-angle end, and TLw is the sum of the distance on the optical axis from the lens surface of the first lens group closest to the object to the lens surface of the subsequent group closest to the image when focused on an object at infinity at the wide-angle end and a back focus of the entire system in air equivalent distance. [Additional Item 47] The zoom lens according to any one of Additional Items 1 to 46, wherein the subsequent group includes an aperture stop, and at least one cemented lens is disposed on the image side of the aperture stop, and satisfies conditional expression (41) expressed by 0.001<DSIcew / TLw<0.12 (41), where DSIcew is the distance on the optical axis between the aperture stop and the cemented surface of the cemented lens on the image side of the aperture stop when focused on an object at infinity at the wide-angle end, and TLw is the sum of the distance on the optical axis from the lens surface of the first lens group closest to the object to the lens surface of the subsequent group closest to the image when focused on an object at infinity at the wide-angle end, and the back focus of the entire system in air equivalent distance.[Additional Item 48] The zoom lens according to any one of Additional Items 1 to 47, wherein the subsequent group includes an aperture stop, and at least one cemented lens is disposed on the object side of the aperture stop, and satisfies conditional expression (42) expressed by 0.001<DSOCew / TLw<0.18 (42), where DSOCew is the distance on the optical axis between the aperture stop and the cemented surface of the cemented lens on the object side of the aperture stop when focused on an object at infinity at the wide-angle end, and TLw is the sum of the distance on the optical axis from the lens surface of the first lens group closest to the object to the lens surface of the subsequent group closest to the image when focused on an object at infinity at the wide-angle end and a back focus of the entire system in air equivalent distance. [Addendum 49] The zoom lens according to any one of Addendums 4 to 7, which satisfies conditional expression (43) expressed as follows: 0.1<ΔN / ΔP<0.75 (43) where ΔN is the amount of movement of the N lens group when varying magnification from the wide-angle end to the telephoto end, ΔP is the amount of movement of the P lens group when varying magnification from the wide-angle end to the telephoto end, and the sign of the amount of movement when varying magnification is negative when moving toward the object side and positive when moving toward the image side. [Addendum 50] The zoom lens according to any one of Addendums 1 to 49, which satisfies conditional expression (44) expressed as follows: 1.5<Dexw / (fw×tanωw)<5 (44) where Dexw is the sum on the optical axis from the paraxial exit pupil position to the lens surface of the subsequent lens group closest to the image side when focused on an object at infinity at the wide-angle end, and the back focus of the entire system in air equivalent distance. [Addendum 51] The zoom lens according to any one of Addendums 2 to 7, satisfying conditional expression (45) expressed by the following equation: 0.4<Fnot×DGP / ft<4 (45) where Fnot is the maximum F-number when focused on an object at infinity at the telephoto end, and DGP is the distance on the optical axis from the lens surface of the P lens group closest to the object to the lens surface of the P lens group closest to the image.[Addendum 52] The zoom lens according to any one of Addendums 13 to 18, which satisfies conditional expression (46) expressed by the following: 0.4<Fnot×(DGP+DGM) / ft<4 (46) where Fnot is the maximum F-number when focused on an object at infinity at the telephoto end, DGP is the distance on the optical axis from the lens surface of the P lens group closest to the object to the lens surface of the P lens group closest to the image, and DGM is the distance on the optical axis from the lens surface of the M lens group closest to the object to the lens surface of the M lens group closest to the image. [Addendum 53] The zoom lens according to any one of Addendums 1 to 52, which includes one lens group between the first lens group and the P lens group. [Addendum 54] A zoom lens according to any one of Addendums 1 to 53, which satisfies conditional expression (47) expressed by: 1.2<TLt / ft<5 (47), where TLt is the sum of the on-optical axial distance from the lens surface of the first lens group closest to the object to the lens surface of the subsequent lens group closest to the image, and the back focus of the entire system in air equivalent distance, when focused on an object at infinity at the telephoto end. [Addendum 55] A zoom lens according to Addendum 12, which satisfies conditional expression (48) expressed by: 0.1<fw / fE<0.7 (48), where fE is the focal length of the final lens group. [Additional Item 56] If the lateral magnification of the focus group when focused on an object at infinity at the wide-angle end is βfw, and the combined lateral magnification of all lenses on the image side of the focus group when focused on an object at infinity at the wide-angle end is βfRw, then 0.3<|(1-βfw. ２ ) × βfRw ２ |<3 (49) [Additional Item 57] The zoom lens according to Supplementary Item 6 satisfies conditional expression (49) expressed by the following formula: |<3 (49) [Additional Item 57] When the lateral magnification of the focus group in a state in which an object at infinity is focused at the telephoto end is βft, and the combined lateral magnification of all lenses on the image side of the focus group in a state in which an object at infinity is focused at the telephoto end is βfRt, then 0.5<|(1-βft ２ ) × βfRt ２|<4 (50) The zoom lens according to supplementary item 6, satisfying conditional expression (50) expressed by: |<4 (50) [Supplementary item 58] The lateral magnification of the focus group when focused on an object at infinity at the wide-angle end is βfw, The composite lateral magnification of all lenses on the image side of the focus group when focused on an object at infinity at the wide-angle end is βfRw, The focal length of the focus group is ffoc, The composite focal length of all lenses on the image side of the focus group when focused on an object at infinity at the wide-angle end is ffRw, The sum of the distance on the optical axis from the paraxial exit pupil position to the lens surface of the subsequent group closest to the image side and the back focus of the entire system in air equivalent distance when focused on an object at infinity at the wide-angle end is Dexw, ２ ) × βfRw ２ 57. The zoom lens according to appended item 6 or 56, which satisfies conditional expression (51) expressed by: 0<(−BRw)×(fw×tanωw)<0.7 (51) when BRw={βfw / (ffoc×γw)−1 / (βfRw×ffRw)−(1 / Dexw)}. [Addendum 59] The lateral magnification of the focus group when focused on an object at infinity at the telephoto end is βft, The composite lateral magnification of all lenses on the image side of the focus group when focused on an object at infinity at the telephoto end is βfRt, The focal length of the focus group is ffoc, The composite focal length of all lenses on the image side of the focus group when focused on an object at infinity at the telephoto end is ffRt, The sum of the distance on the optical axis from the paraxial exit pupil position to the lens surface of the subsequent group closest to the image side and the back focus of the entire system in air equivalent distance when focused on an object at infinity at the telephoto end is Dext, The maximum half angle of view when focused on an object at infinity at the telephoto end is ωt, and γt=(1-βft ２ ) × βfRt ２The zoom lens according to supplementary item 6 or 57 satisfies conditional expression (52) expressed by the following formula: 0<(-BRt)×(ft×tanωt)<0.5 (52) where BRt={βft / (ffoc×γt)-1 / (βfRt×ffRt)-(1 / Dext)}. [Supplementary item 60] The zoom lens according to any one of supplementary items 1 to 59, including an aperture stop, and including at least three lenses between the first lens group and the aperture stop. [Supplementary item 61] The zoom lens according to any one of supplementary items 1 to 60, including an aperture stop, and including at least three positive lenses between the first lens group and the aperture stop. [Supplementary item 62] The zoom lens according to any one of supplementary items 4 to 7, including an aperture stop, and including at least three lenses between the aperture stop and the N lens group. [Addendum 63] The zoom lens according to any one of Addendums 4 to 7, including an aperture stop, and including at least two positive lenses between the aperture stop and the N lens group. [Addendum 64] The zoom lens according to Addendum 6, in which the focus group includes two or fewer lenses. [Addendum 65] The zoom lens according to Addendum 5, in which the final lens group includes two or fewer lenses. [Addendum 66] The zoom lens according to any one of Addendums 1 to 65, in which the lens surface of the first lens group closest to the image side is concave. [Addendum 67] The zoom lens according to any one of Addendums 1 to 66, in which, of the movement loci of each lens group that moves during magnification change from the wide-angle end to the telephoto end, there are five different movement loci. [Addendum 68] The zoom lens according to any one of Addendums 1 to 66, in which, of the movement loci of each lens group that moves during magnification change from the wide-angle end to the telephoto end, there are four different movement loci. [Supplementary Item 69] The zoom lens according to any one of Supplementary Items 1 to 66, wherein, of the movement loci of each lens group that moves during magnification change from the wide-angle end to the telephoto end, there are three movement loci that are different from one another.[Addendum 70] The zoom lens according to any one of Addendums 1 to 69, wherein at least one of the lens closest to the object in the zoom lens and the second lens from the object side in the zoom lens is a negative lens, and satisfies conditional expression (53) expressed as follows, where Nobn is the refractive index at the d-line of at least one of the lens closest to the object in the zoom lens and the second lens from the object side in the zoom lens. [Addendum 71] The zoom lens according to Addendum 70, wherein the lens closest to the object in the zoom lens is a negative lens and satisfies conditional expression (53). [Addendum 72] An imaging device comprising the zoom lens according to any one of Addendums 1 to 71.

[0326] All publications, patent applications, and technical standards mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent application, or technical standard was specifically and individually indicated to be incorporated by reference.

Claims

1. The first lens group has a negative refractive power, and the second lens group has a negative refractive power. the subsequent group includes at least three lens groups; one of the at least three lens groups is a P lens group having a positive refractive power; During magnification change, the distance between the first lens group and the subsequent lens group changes, and all distances between adjacent lens groups in the subsequent lens group change. The focal length of the entire system when focused on an object at infinity at the wide-angle end is fw. The focal length of the entire system when focused on an object at infinity at the telephoto end is ft. 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, If the maximum half angle of view when focused on an object at infinity at the wide-angle end is ωw, 1.5<ft / fw<6 (1) 0.4<Bfw / (fw×tanωw)<2 (2) A zoom lens that satisfies the conditional expressions (1) and (2) expressed by:

2. 2. The zoom lens according to claim 1, wherein the P lens group has the largest amount of movement toward the object side during zooming from the wide-angle end to the telephoto end among the lens groups in the subsequent group.

3. The amount of movement of the P lens group during magnification change from the wide-angle end to the telephoto end is ΔP, If the sign of the movement amount during magnification is negative when moving toward the object side and positive when moving toward the image side, 0.9<(-ΔP) / fw<6 (3) 3. The zoom lens according to claim 2, which satisfies conditional expression (3) expressed as follows:

4. 3. The zoom lens according to claim 2, further comprising an N lens group having negative refractive power disposed closer to the image side than the P lens group.

5. 5. The zoom lens according to claim 4, further comprising a final lens group located closest to the image side within said zoom lens, said final lens group being closer to the image side than said N lens group.

6. 5. The zoom lens according to claim 4, wherein at least a part of the N lens groups is a focus group that moves along the optical axis during focusing.

7. If the focal length of the N lens group is fN, 0.5<(-fN) / fw<7 (4) 5. The zoom lens according to claim 4, which satisfies conditional expression (4) expressed as follows:

8. If the maximum F-number when focusing on an object at infinity at the telephoto end is Fnot, 1.2<Fnot<5.8 (5) 2. The zoom lens according to claim 1, which satisfies conditional expression (5) expressed by:

9. The maximum F-number when the lens is focused on an object at infinity at the telephoto end is Fnot. When the maximum F-number at the wide-angle end is Fnow and the lens is focused on an object at infinity, 0.95<Fnot / Fnow<1.8 (6) 2. The zoom lens according to claim 1, which satisfies conditional expression (6) expressed as follows:

10. If the focal length of the P lens group is fP, 0.5<fP / fw<6 (7) 3. The zoom lens according to claim 2, which satisfies conditional expression (7) expressed as follows:

11. 35<ωw<54 (8) 2. The zoom lens according to claim 1, which satisfies conditional expression (8) expressed as follows:

12. 6. The zoom lens according to claim 5, wherein the final lens group has positive refractive power.

13. 5. The zoom lens according to claim 4, further comprising an M lens group between the P lens group and the N lens group.

14. Among the lens groups in the subsequent group, the P lens group has the largest amount of movement toward the object side during zooming from the wide-angle end to the telephoto end, an N lens group having negative refractive power disposed on the image side of the P lens group, an M lens group between the P lens group and the N lens group, The amount of movement of the P lens group during magnification change from the wide-angle end to the telephoto end is ΔP, If the sign of the movement amount during magnification is negative when moving toward the object side and positive when moving toward the image side, 0.9<(-ΔP) / fw<6 (3) 2. The zoom lens according to claim 1, which satisfies conditional expression (3) expressed as follows:

15. 14. The zoom lens of claim 13, wherein the M lens group has positive refractive power.

16. If the focal length of the M lens group is fM, 0.01<fw / fM<0.35 (9) 14. The zoom lens according to claim 13, which satisfies conditional expression (9) expressed as follows:

17. Among the positive lenses in the M lens group, the refractive index of the positive lens closest to the image side with respect to the d line is NMp, When the Abbe number of the positive lens closest to the image side among the positive lenses in the M lens group is νMp based on the d-line, 1.73<NMp<2.5 (10) 10<νMp<50 (11) 14. The zoom lens according to claim 13, which satisfies conditional expressions (10) and (11) expressed by:

18. 14. The zoom lens according to claim 13, further comprising an aperture stop located closest to the object side of the M lens group.

19. 2. The zoom lens according to claim 1, wherein the first lens group includes a negative meniscus lens having a concave surface facing the image side, the negative meniscus lens being closest to the object side.

20. If the focal length of the first lens group is f1, 1<(-f1) / fw<2.5 (12) 2. The zoom lens according to claim 1, which satisfies conditional expression (12) expressed as follows:

21. When the distance on the optical axis from the lens surface of the first lens group closest to the object side to the lens surface of the first lens group closest to the image side is DG1, 0.71<DG1 / (fw×tanωw)<2.5 (13) 2. The zoom lens according to claim 1, which satisfies conditional expression (13) expressed as follows:

22. If the distance on the optical axis from the lens surface of the P lens group closest to the object side to the lens surface of the P lens group closest to the image side is defined as DGP, 0.35<DGP / (fw×tanωw)<2.5 (14) 3. The zoom lens according to claim 2, which satisfies conditional expression (14) expressed as follows:

23. When the distance on the optical axis from the lens surface of the first lens group closest to the object side to the paraxial entrance pupil position in a state in which the lens surface is focused on an object at infinity at the wide-angle end is Denw, 1<Denw / fw<2.2 (15) 2. The zoom lens according to claim 1, which satisfies conditional expression (15) expressed as follows:

24. If the average value of the specific gravity of all the lenses in the first lens group is G1ave, 1<G1ave<5 (16) 2. The zoom lens according to claim 1, which satisfies conditional expression (16) expressed as follows:

25. If the average specific gravity of all the lenses in the P lens group is Gpave, then 1<GPave<5 (17) 3. The zoom lens according to claim 2, which satisfies conditional expression (17) expressed as follows:

26. The average value of the specific gravity of all the lenses in the focus group is Gfave, DGfoc is the distance on the optical axis from the lens surface of the focus group closest to the object side to the lens surface of the focus group closest to the image side, If the focal length of the focus group is ffoc, 0.03<Gfave×DGfoc / |ffoc|<0.9 (18) 7. The zoom lens according to claim 6, which satisfies conditional expression (18) expressed as follows:

27. The focal length of the first lens group is f1, If the focal length of the P lens group is fP, 0.3<(-f1) / fP<1.5 (19) 3. The zoom lens according to claim 2, which satisfies conditional expression (19) expressed as follows:

28. The focal length of the first lens group is f1, If the focal length of the M lens group is fM, 0<(-f1) / fM<0.7 (20) 14. The zoom lens according to claim 13, which satisfies conditional expression (20) expressed as follows:

29. The focal length of the P lens group is fP, If the focal length of the M lens group is fM, 0<fP / fM<2 (21) 14. The zoom lens according to claim 13, which satisfies conditional expression (21) expressed as follows:

30. If the focal length of the focus group is ffoc, 1.2<(-ffoc) / (fw×tanωw)<5.5 (22) 7. The zoom lens according to claim 6, which satisfies conditional expression (22) expressed as follows:

31. the first lens group includes at least one aspheric lens; The paraxial radius of curvature of the object side surface of the aspheric lens in the first lens group is Rc1f, The paraxial radius of curvature of the image side surface of the aspheric lens in the first lens group is Rc1r, The radius of curvature at the position of the maximum effective diameter of the object side surface of the aspheric lens of the first lens group is Ry1f, When the radius of curvature at the position of the maximum effective diameter of the image side surface of the aspheric lens of the first lens group is Ry1r, 1.05<(1 / Rc1f-1 / Rc1r) / (1 / Ry1f-1 / Ry1r)<8 （２３） 2. The zoom lens according to claim 1, which satisfies conditional expression (23) expressed as follows:

32. the P lens group includes at least one aspheric lens, The paraxial radius of curvature of the object side surface of the aspheric lens in the P lens group is RcPf, The radius of curvature at the position of the maximum effective diameter of the object side surface of the aspheric lens of the P lens group is RyPf, The refractive index of the aspherical lens in the P lens group with respect to the d line is NP, If the focal length of the P lens group is fP, 0.01<(1 / RcPf-1 / RyPf)×NP×fP<5 (24) 3. The zoom lens according to claim 2, which satisfies conditional expression (24) expressed as follows:

33. The N lens group includes at least one aspheric lens, The paraxial radius of curvature of the object side surface of the aspheric lens in the N lens group is RcNf, The paraxial radius of curvature of the image side surface of the aspheric lens of the N lens group is RcNr, The radius of curvature at the position of the maximum effective diameter of the object side surface of the aspheric lens of the N lens group is RyNf, When the radius of curvature at the position of the maximum effective diameter of the image side surface of the aspheric lens of the N lens group is RyNr, 0.7<(1 / RcNf-1 / RcNr) / (1 / RyNf-1 / RyNr)<0.996 (25) 5. The zoom lens according to claim 4, which satisfies conditional expression (25) expressed as follows:

34. the final lens group includes at least one aspheric lens; The paraxial radius of curvature of the object side surface of the aspheric lens in the final lens group is RcEf, The paraxial radius of curvature of the image side surface of the aspheric lens in the final lens group is RcEr, The radius of curvature at the position of the maximum effective diameter of the object side surface of the aspheric lens of the final lens group is RyEf, When the radius of curvature at the position of the maximum effective diameter of the image side surface of the aspheric lens in the final lens group is RyEr, 1.01<(1 / RcEf-1 / RcEr) / (1 / RyEf-1 / RyEr)<2 （２６） 6. The zoom lens according to claim 5, which satisfies conditional expression (26) expressed as follows:

35. the first lens group includes at least one negative lens; The Abbe number of the negative lens in the first lens group based on the d-line is ν When the partial dispersion ratio between the g-line and the F-line of the negative lens in the first lens group is θgF1n, 55<ν1n<110 (27) 0.003<θgF1n-(0.6438-0.001682×ν1n)<0.05 （２８） 2. The zoom lens according to claim 1, which satisfies conditional expressions (27) and (28) expressed by:

36. the P lens group includes at least one negative lens, The Abbe number of the negative lens in the P lens group based on the d-line is νPn, When the partial dispersion ratio between the g-line and the F-line of the negative lens in the P lens group is θgFPn, 55<νPn<110 (29) 0.003<θgFPn-(0.6438-0.001682×νPn)<0.05 （３０） 3. The zoom lens according to claim 2, which satisfies conditional expressions (29) and (30) expressed by:

37. The N lens group includes at least one negative lens, the Abbe number of the negative lens in the N lens group based on the d-line is νNn, When the partial dispersion ratio between the g-line and the F-line of the negative lens in the N lens group is θgFNn, 55<νNn<110 (31) 0.003<θgFNn-(0.6438-0.001682×νNn)<0.05 （３２） 5. The zoom lens according to claim 4, which satisfies conditional expressions (31) and (32) expressed by:

38. the M lens group includes at least one negative lens, the Abbe number of the negative lens in the M lens group based on the d-line is νMn, When the partial dispersion ratio between the g-line and the F-line of the negative lens in the M lens group is θgFMn, 55<νMn<110 (33) 0.003<θgFMn-(0.6438-0.001682×νMn)<0.06 （３４） 14. The zoom lens according to claim 13, which satisfies conditional expressions (33) and (34) expressed by the following:

39. the final lens group includes at least one positive lens, the Abbe number of the positive lens in the final lens group based on the d-line is νEp; When the partial dispersion ratio between the g-line and the F-line of the positive lens in the final lens group is θgFEp, 55<νEp<110 (35) 0.003<θgFEp-(0.6438-0.001682×νEp)<0.05 （３６） 6. The zoom lens according to claim 5, which satisfies conditional expressions (35) and (36) expressed by:

40. the first lens group includes at least one positive lens, The refractive index of the positive lens in the first lens group with respect to the d-line is N1p, When the Abbe number of the positive lens in the first lens group based on the d-line is ν1p, 1.8<N1p<2.3 (37) 10<ν1p<45 (38) 2. The zoom lens according to claim 1, which satisfies conditional expressions (37) and (38) expressed by:

41. 6. The zoom lens according to claim 5, wherein the final lens group is fixed relative to the image plane during zooming.

42. 20. The zoom lens according to claim 19, wherein the first lens group includes a biconcave lens arranged closer to the image side than the negative meniscus lens, and a positive lens arranged closer to the image side than the biconcave lens.

43. 2. The zoom lens according to claim 1, wherein the first lens group at the telephoto end is located closer to the image side than the first lens group at the wide-angle end.

44. 2. The zoom lens according to claim 1, wherein the first lens group at the telephoto end is located closer to the object side than the first lens group at the wide-angle end.

45. the subsequent group includes an aperture stop; at least one negative lens having a concave surface facing the object side is disposed on the image side of the aperture stop, The distance on the optical axis between the aperture stop and the negative lens with a concave surface facing the object side when focused on an object at infinity at the wide-angle end is DSInw, When the lens is focused on an object at infinity at the wide-angle end, the lens closest to the object in the first lens group is If the sum of the distance on the optical axis from the lens surface to the lens surface of the subsequent lens group closest to the image side and the back focus of the entire system in air equivalent distance is denoted by TLw, 0.001<DSInw / TLw<0.12 (39) 2. The zoom lens according to claim 1, which satisfies conditional expression (39) expressed as follows:

46. the subsequent group includes an aperture stop; at least one negative lens having a concave surface facing an image side is disposed on the object side of the aperture stop, The distance on the optical axis between the aperture stop and the negative lens having a concave surface facing the image side when focused on an object at infinity at the wide-angle end is DSOnw. When the sum of the distance on the optical axis from the lens surface of the first lens group closest to the object side to the lens surface of the subsequent lens group closest to the image side in a state in which the lens surface is focused on an object at infinity at the wide-angle end and the back focus of the entire system in terms of an air equivalent distance is denoted by TLw. 0.001<DSOnw / TLw<0.18 (40) 2. The zoom lens according to claim 1, which satisfies conditional expression (40) expressed as follows:

47. the subsequent group includes an aperture stop; At least one cemented lens is disposed on the image side of the aperture stop, The distance on the optical axis between the aperture stop and the cemented surface of the cemented lens on the image side of the aperture stop when focused on an object at infinity at the wide-angle end is DSICew, When the sum of the distance on the optical axis from the lens surface of the first lens group closest to the object side to the lens surface of the subsequent lens group closest to the image side in a state in which the lens surface is focused on an object at infinity at the wide-angle end and the back focus of the entire system in terms of an air equivalent distance is denoted by TLw. 0.001<DSIcew / TLw<0.12 (41) 2. The zoom lens according to claim 1, which satisfies conditional expression (41) expressed as follows:

48. the subsequent group includes an aperture stop; At least one cemented lens is disposed on the object side of the aperture stop, The distance on the optical axis between the aperture stop and the cemented surface of the cemented lens on the object side of the aperture stop when focused on an object at infinity at the wide-angle end is DSOCew. When the sum of the distance on the optical axis from the lens surface of the first lens group closest to the object side to the lens surface of the subsequent lens group closest to the image side in a state in which the lens surface is focused on an object at infinity at the wide-angle end and the back focus of the entire system in terms of an air equivalent distance is denoted by TLw. 0.001<DSOcew / TLw<0.18 (42) 2. The zoom lens according to claim 1, which satisfies conditional expression (42) expressed as follows:

49. The amount of movement of the N lens group when changing the magnification from the wide-angle end to the telephoto end is ΔN, The amount of movement of the P lens group during magnification change from the wide-angle end to the telephoto end is ΔP, If the sign of the movement amount during magnification is negative when moving toward the object side and positive when moving toward the image side, 0.1<ΔN / ΔP<0.75 (43) 5. The zoom lens according to claim 4, which satisfies conditional expression (43) expressed as follows:

50. When the sum of the distance on the optical axis from the paraxial exit pupil position to the lens surface of the rear lens group closest to the image side in a state in which the lens is focused on an object at infinity at the wide-angle end and the back focus of the entire system in terms of an air equivalent distance is represented by Dexw, 1.5<Dexw / (fw×tanωw)<5 (44) 2. The zoom lens according to claim 1, which satisfies conditional expression (44) expressed as follows:

51. The maximum F-number when the lens is focused on an object at infinity at the telephoto end is Fnot. If the distance on the optical axis from the lens surface of the P lens group closest to the object side to the lens surface of the P lens group closest to the image side is defined as DGP, 0.4<Fnot×DGP / ft<4 (45) 3. The zoom lens according to claim 2, which satisfies conditional expression (45) expressed as follows:

52. The maximum F-number when the lens is focused on an object at infinity at the telephoto end is Fnot. The distance on the optical axis from the lens surface closest to the object side of the P lens group to the lens surface closest to the image side of the P lens group is DGP, If the distance on the optical axis from the lens surface of the M lens group closest to the object side to the lens surface of the M lens group closest to the image side is defined as DGM, 0.4<Fnot×(DGP+DGM) / ft<4 (46) 14. The zoom lens according to claim 13, which satisfies conditional expression (46) expressed as follows:

53. 2. The zoom lens according to claim 1, further comprising one lens group between the first lens group and the P lens group.

54. When the sum of the distance on the optical axis from the lens surface of the first lens group closest to the object side to the lens surface of the subsequent lens group closest to the image side in a state in which the lens is focused on an object at infinity at the telephoto end and the back focus of the entire system in terms of an air equivalent distance is denoted by TLt, 1.2<TLt / ft<5 (47) 2. The zoom lens according to claim 1, which satisfies conditional expression (47) expressed as follows:

55. If the focal length of the final lens group is fE, 0.1<fw / fE<0.7 (48) 13. The zoom lens according to claim 12, which satisfies conditional expression (48) expressed as follows:

56. The lateral magnification of the focus group when focused on an object at infinity at the wide-angle end is βfw, When the composite lateral magnification of all the lenses on the image side of the focus group in a state in which an object at infinity is focused at the wide-angle end is βfRw, 0.3<|(1-βfw ２ )×βfRw ２ |<3 (49) 7. The zoom lens according to claim 6, which satisfies conditional expression (49) expressed as follows:

57. The lateral magnification of the focus group when focused on an object at infinity at the telephoto end is βft, When the composite lateral magnification of all the lenses on the image side of the focus group in a state in which an object at infinity is focused at the telephoto end is βfRt, 0.5<|(1-βft ２ )×βfRt ２ |<4 (50) 7. The zoom lens according to claim 6, which satisfies conditional expression (50) expressed as follows:

58. The focal length of the focus group is ffoc, The composite focal length of all the lenses on the image side of the focus group when focused on an object at infinity at the wide-angle end is ffRw. Denote by Dexw the sum of the distance on the optical axis from the paraxial exit pupil position to the lens surface of the rear lens group closest to the image side when focused on an object at infinity at the wide-angle end, and the back focus of the entire system in terms of an air equivalent distance, γw=(1-β&w ２ )×βfRw ２ 、 When BRw={βfw / (ffoc×γw)−1 / (βfRw×ffRw)−(1 / Dexw)}, 0<(-BRw)×(fw×tanωw)<0.7 (51) 57. The zoom lens according to claim 56, which satisfies conditional expression (51) represented by:

59. The focal length of the focus group is ffoc, The composite focal length of all the lenses on the image side of the focus group when focused on an object at infinity at the telephoto end is ffRt. Dext is the sum of the distance on the optical axis from the paraxial exit pupil position to the lens surface of the rear lens group closest to the image side when focused on an object at infinity at the telephoto end, and the back focus of the entire system in air equivalent distance; The maximum half angle of view when focused on an object at infinity at the telephoto end is ωt, γt=(1-βft ２ )×βfRt ２ 、 When BRt={βft / (ffoc×γt)−1 / (βfRt×ffRt)−(1 / Dext)}, 0<(-BRt)×(ft×tanωt)<0.5 (52) 58. The zoom lens according to claim 57, which satisfies conditional expression (52) expressed by:

60. Including the aperture stop, 2. The zoom lens according to claim 1, further comprising at least three lenses between the first lens group and the aperture stop.

61. Including the aperture stop, 2. The zoom lens according to claim 1, further comprising at least three positive lenses between the first lens group and the aperture stop.

62. Including the aperture stop, 5. The zoom lens according to claim 4, further comprising at least three lenses between the aperture stop and the N lens group.

63. Including the aperture stop, 5. The zoom lens according to claim 4, further comprising at least two positive lenses between the aperture stop and the N lens group.

64. 7. The zoom lens according to claim 6, wherein the focus group includes two or less lenses.

65. 6. The zoom lens according to claim 5, wherein the final lens group includes two or less lenses.

66. 2. The zoom lens according to claim 1, wherein the lens surface of the first lens group closest to the image side is a concave surface.

67. 2. The zoom lens according to claim 1, wherein the number of different movement loci of each lens group that moves during zooming from the wide-angle end to the telephoto end is five.

68. 2. The zoom lens according to claim 1, wherein among the movement loci of each lens group that moves during magnification change from the wide-angle end to the telephoto end, there are four movement loci that are different from one another.

69. 2. The zoom lens according to claim 1, wherein among the movement loci of each lens group that moves during zooming from the wide-angle end to the telephoto end, there are three movement loci that are different from one another.

70. At least one of the lens closest to the object side of the zoom lens and the second lens from the object side of the zoom lens is a negative lens, When the refractive index of at least one of the negative lenses, which are the lens closest to the object side of the zoom lens and the second lens from the object side of the zoom lens, is Nobn, 1.7<Nobn<2.2 (53) 2. The zoom lens according to claim 1, which satisfies conditional expression (53) expressed as follows:

71. 71. The zoom lens according to claim 70, wherein the lens of the zoom lens closest to the object side is a negative lens, and satisfies the conditional expression (53).

72. An imaging device comprising the zoom lens according to any one of claims 1 to 71.