Zoom lens and imaging apparatus

Abstract

To provide a zoom lens which has a large image circle and a wide angle and is compactly configured and excellent in optical performance and an imaging apparatus including the zoom lens.SOLUTION: The zoom lens includes a first lens group which is arranged closest to an object side and has positive refractive power, a negative group which is arranged adjacent to an image side of the first lens group and composed of two or less lens groups and has negative refractive power as a whole, an N lens group which is arranged closer to the image side than the negative group and has negative refractive power, a P lens group which is arranged closer to the image side than the negative group and has positive refractive power, and a final lens group which is arranged closest to the image side. When varying power, all intervals between the adjacent lens groups change. The zoom lens satisfies a predetermined conditional expression.SELECTED DRAWING: Figure 1

Description

[Technical field]

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

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

[0003] [Patent Document 1] JP 2016-004076 A Summary of the Invention [Problem to be solved by the invention]

[0004] There is a demand for zoom lenses that have a large image circle, a wide angle, are compact, and have good optical performance. These demands are becoming higher every year.

[0005] The present disclosure provides a zoom lens that has a large image circle, a wide angle, is compact, and has good optical performance, and an imaging device equipped with this zoom lens. [Means for solving the problem]

[0006] A first aspect of the present disclosure is a zoom lens comprising: a first lens group having positive refractive power and arranged closest to the object; a negative group arranged adjacent to the image side of the first lens group and consisting of two or less lens groups, the negative group having negative refractive power as a whole; an N lens group having negative refractive power and arranged closer to the image side than the negative group; a P lens group having positive refractive power and arranged closer to the image side than the negative group; and a final lens group arranged closest to the image side, wherein all of the intervals between adjacent lens groups change during magnification change, and the following conditional formula (1) is satisfied: -6 <fN / f1<-0.55 (1) Here, the focal length of the N lens group is fN, and the focal length of the 1st lens group is f1.

[0007] A second aspect of the present disclosure is the zoom lens of the first aspect, in which the first lens group is fixed with respect to the image plane during zooming.

[0008] A third aspect of the present disclosure is the zoom lens of the first aspect, in which the final lens group is fixed with respect to the image plane during zooming.

[0009] A fourth aspect of the present disclosure is the zoom lens of the first aspect, in which a P lens group is disposed adjacent to the image side of the N lens group, and a final lens group is disposed adjacent to the image side of the P lens group.

[0010] A fifth aspect of the present disclosure is the zoom lens of the first aspect, in which a part of the first lens group moves along the optical axis during focusing.

[0011] A sixth aspect of the present disclosure is a zoom lens of the fifth aspect, wherein the first lens group includes, in succession from the most object side to the image side, at least a 1a sub group, a 1b sub group, and a 1c sub group, and during focusing, the distance between the 1a sub group and the 1b sub group changes, and the distance between the 1b sub group and the 1c sub group changes.

[0012] A seventh aspect of the present disclosure is a zoom lens of the fifth aspect, wherein the first lens group consists of, in order from the object side to the image side, a 1a sub group, a 1b sub group, and a 1c sub group, and during focusing, the 1a sub group is fixed with respect to the image plane, and the 1b sub group and the 1c sub group move on mutually different trajectories.

[0013] An eighth aspect of the present disclosure is a zoom lens according to the first aspect, in which, 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 in a state in which the zoom lens is focused on an object at infinity at the wide-angle end is Denw, and when the focal length of the zoom lens in a state in which the zoom lens is focused on an object at infinity at the wide-angle end is fw, 1.2 <Denw / fw<8 (2) The condition (2) expressed by the following formula (2) is satisfied.

[0014] A ninth aspect of the present disclosure is a zoom lens according to the first aspect, wherein, when the focal length of the negative group is fUN and the focal length of the N lens group is fN, 0.118 <fUN / fN<0.25 (3) The condition (3) is satisfied.

[0015] A tenth aspect of the present disclosure is a zoom lens according to the first aspect, wherein, when varying magnification from the wide-angle end to the telephoto end, the N lens group moves along a locus that is convex towards the object side.

[0016] An eleventh aspect of the present disclosure is the zoom lens of the first aspect, wherein the lens closest to the object side of the zoom lens is a negative lens, and the second lens from the object side of the zoom lens is a positive lens.

[0017] A twelfth aspect of the present disclosure is the zoom lens of the first aspect, wherein the first lens group includes one negative lens and four or more positive lenses.

[0018] A thirteenth aspect of the present disclosure is the zoom lens of the first aspect, wherein the first lens group includes, in succession from the most object side to the image side, a negative lens, a positive lens, and a positive lens.

[0019] In a fourteenth aspect of the present disclosure, in the zoom lens of the first aspect, when the longest air space on the optical axis from the lens surface of the P lens group closest to the object to the lens surface of the final lens group closest to the image is defined as the longest air space at the wide-angle end when focused on an object at infinity, the EX group is arranged to be insertable and removable in the optical path with the longest air space, thereby changing the focal length of the zoom lens while keeping the imaging position constant.

[0020] A fifteenth aspect of the present disclosure is a zoom lens according to the fourteenth aspect, in which the maximum image height changes by inserting or removing the EX group.

[0021] A sixteenth aspect of the present disclosure is the zoom lens of the fifth aspect, wherein the first lens group includes at least a 1a sub group and a 1b sub group, which are successively arranged from the most object side to the image side, and wherein the distance between the 1a sub group and the 1b sub group changes during focusing, and when the focal length of the 1a sub group is f1a, -0.85 <f1 / f1a<0.15 (4) The condition (4) is satisfied.

[0022] A seventeenth aspect of the present disclosure is a zoom lens according to the first aspect, wherein, when the focal length of the negative group is fUN, -0.4 <fUN / f1<-0.09 (5) The condition (5) is satisfied.

[0023] An eighteenth aspect of the present disclosure is a zoom lens according to the first aspect, in which, when the lens surface closest to the object in the first lens group is focused on an object at infinity at the wide-angle end, the distance on the optical axis to the paraxial entrance pupil position is Denw, 0.4 <Denw / f1<1.6 (6) The condition (6) is satisfied.

[0024] A nineteenth aspect of the present disclosure is a zoom lens according to the first aspect, in which, 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 in a state in which an object at infinity is focused at the wide-angle end is Denw, and when the maximum image height in a state in which an object at infinity is focused at the wide-angle end is IHw, 3.4 <Denw / IHw<7.5 (7) Condition (7) expressed by the following formula (7) is satisfied.

[0025] A twentieth aspect of the present disclosure relates to the zoom lens of the first aspect, where the amount of displacement of the N lens group in the optical axis direction when changing magnification from the wide-angle end to the telephoto end is MovN, the focal length of the zoom lens when focused on an object at infinity at the telephoto end is ft, and the focal length of the zoom lens when focused on an object at infinity at the wide-angle end is fw, and the sign of the amount of displacement is negative when the N lens group moves toward the object side and positive when it moves toward the image side, -0.4 <MovN / (f1 / log(ft / fw))<0.1 (8) The condition (8) is satisfied.

[0026] A twenty-first aspect of the present disclosure is a zoom lens according to the first aspect, in which, when a back focus in an air-equivalent distance when focused on an object at infinity at the wide-angle end is Bfw and a maximum image height when focused on an object at infinity at the wide-angle end is IHw, 1.9 <Bfw / IHw<6 (9) Condition (9) expressed by the following formula (9) is satisfied.

[0027] A 22nd aspect of the present disclosure is a zoom lens according to the 6th aspect, wherein the 1a sub group includes an aspheric lens having at least one surface whose absolute value of the radius of curvature at the position of the maximum effective diameter is larger than the absolute value of the paraxial radius of curvature.

[0028] A 23rd aspect of the present disclosure is a zoom lens according to the 6th aspect, wherein the 1c sub group includes an aspheric lens having at least one surface whose absolute value of the radius of curvature at the position of the maximum effective diameter is larger than the absolute value of the paraxial radius of curvature.

[0029] In a 24th aspect of the present disclosure, in the zoom lens of the first aspect, the negative group includes an aspheric lens having at least one surface whose absolute value of the radius of curvature at the position of the maximum effective diameter is smaller than the absolute value of the paraxial radius of curvature.

[0030] A 25th aspect of the present disclosure is the zoom lens of the first aspect, wherein the P lens group includes an aspheric lens having at least one surface whose absolute value of the radius of curvature at the position of the maximum effective diameter is larger than the absolute value of the paraxial radius of curvature.

[0031] A 26th aspect of the present disclosure is a zoom lens of the first aspect, in which, when focused on an object at infinity at the wide-angle end, the longest air space on the optical axis from the lens surface closest to the object in the P lens group to the lens surface closest to the image in the final lens group is defined as the longest air space, PF is the Petzval sum from the lens surface closest to the object in the first lens group to the object-side surface constituting the longest air space, and IHw is the maximum image height when focused on an object at infinity at the wide-angle end: 0.12 <PF×IHw<0.25 (10) Condition (10) expressed by the following formula is satisfied.

[0032] A 27th aspect of the present disclosure is an imaging device including the zoom lens of any one of the first to twenty-sixth aspects.

[0033] In addition, in this specification, "consisting of" and "consisting of" are intended to mean that, in addition to the listed components, the following may be included: a lens that has substantially no refractive power, optical elements other than lenses such as an aperture, a filter, and a cover glass, and mechanical parts such as a lens flange, a lens barrel, an image sensor, and an image stabilization mechanism.

[0034] In this specification, "a group having positive refractive power" means that the group as a whole has positive refractive power. Similarly, "a group having negative refractive power" means that the group as a whole has negative refractive power. In this specification, the "first lens group," "lens group," "N lens group," "P lens group," "final lens group," and "focusing group" are not limited to configurations consisting of multiple lenses, and may be configurations consisting of only one lens.

[0035] A compound aspherical lens (a lens in which a lens (e.g. a spherical lens) and an aspherical film formed on that lens are integrally constructed and function as a single aspherical lens overall) is not considered a cemented lens, but is treated as a single lens. Unless otherwise specified, the radius of curvature, sign of refractive power, and surface shape of lenses including aspheric surfaces are those in the paraxial region. The sign of the radius of curvature of a surface with a convex shape facing the object side is positive, and the sign of the radius of curvature of a surface with a convex shape facing the image side is negative.

[0036] "Back focus in air-equivalent distance" is the air-equivalent distance on the optical axis from the lens surface closest to the image side of the zoom lens to the image plane. The "focal length" used in the conditional formula is the paraxial focal length. The "distance on the optical axis" used in the conditional formula is a geometric distance unless otherwise specified. The values ​​used in the conditional formula are values ​​based on the d-line when focused on an object at infinity, unless otherwise specified. Effect of the Invention

[0037] According to the present disclosure, it is possible to provide a zoom lens that has a large image circle, a wide angle, is compact, and has good optical performance, and an imaging device equipped with this zoom lens. [Brief description of the drawings]

[0038] [Figure 1] 1A and 1B correspond to the zoom lens of Example 1 and are diagrams showing a cross-sectional view of the configuration of a zoom lens according to an embodiment and a movement locus thereof. [Diagram 2] FIG. 2 is a cross-sectional view of the configuration of the zoom lens in FIG. 1 and is also a diagram for explaining symbols in conditional expressions. [Diagram 3] FIG. 2 is a diagram for explaining the positions of an effective diameter and a maximum effective diameter. [Figure 4] FIG. 2 is a diagram showing insertion and removal of an EX group in the zoom lens of FIG. 1, and is also a diagram for explaining symbols in conditional expressions. [Diagram 5] FIG. 1 is a cross-sectional view of a configuration of a zoom lens according to Example 1-1. [Figure 6]3A to 3C are diagrams showing various aberrations of the zoom lens of Example 1. [Figure 7] 5A to 5C are diagrams showing various aberrations of the zoom lens of Example 1-1. [Figure 8] 11A and 11B are diagrams illustrating a cross-sectional view of the configuration of a zoom lens according to a second embodiment and a movement locus thereof. [Figure 9] 6A to 6C are diagrams showing various aberrations of the zoom lens of Example 2. [Figure 10] 11A and 11B are diagrams illustrating a cross-sectional view of the configuration of a zoom lens according to a third embodiment and a movement locus thereof. [Figure 11] 11A to 11C are diagrams showing various aberrations of the zoom lens of Example 3. [Figure 12] 11A and 11B are diagrams illustrating a cross-sectional view of the configuration of a zoom lens according to a fourth embodiment and a movement locus thereof. [Figure 13] 11A to 11C are diagrams showing various aberrations of the zoom lens of Example 4. [Figure 14] 13A and 13B are diagrams illustrating a cross-sectional view of the configuration of a zoom lens according to a fifth embodiment and a movement locus thereof. [Figure 15] 13A to 13C are diagrams showing various aberrations of the zoom lens of Example 5. [Figure 16] 13A and 13B are diagrams illustrating a cross-sectional view of the configuration of a zoom lens according to a sixth embodiment and a movement locus thereof. [Figure 17] 13A to 13C are diagrams showing various aberrations of the zoom lens of Example 6. [Figure 18] 13A and 13B are diagrams illustrating a cross-sectional view and a movement locus of a zoom lens according to a seventh embodiment. [Figure 19] 13A to 13C are diagrams showing various aberrations of the zoom lens of Example 7. [Figure 20] 13A and 13B are diagrams illustrating a cross-sectional view of the configuration of a zoom lens according to an eighth embodiment and a movement locus thereof. [Figure 21] 13A to 13C are diagrams showing various aberrations of the zoom lens of Example 8. [Figure 22] 13A and 13B are diagrams illustrating a cross-sectional view and a movement locus of a zoom lens according to a ninth embodiment. [Diagram 23] 13A to 13C are diagrams showing various aberrations of the zoom lens of Example 9. [Figure 24] 13A and 13B are diagrams illustrating a cross-sectional view and a movement locus of a zoom lens according to a tenth embodiment. [Diagram 25] 21A to 21C are diagrams showing various aberrations of the zoom lens of Example 10. [Figure 26] 13A and 13B are diagrams illustrating a cross-sectional view of the configuration of a zoom lens according to an eleventh embodiment and a movement locus thereof. [Figure 27] 13A to 13C are diagrams showing various aberrations of the zoom lens of Example 11. [Figure 28] 13A and 13B are diagrams illustrating a cross-sectional view and a movement locus of a zoom lens according to a twelfth embodiment. [Figure 29] 23A to 23C are diagrams showing various aberrations of the zoom lens of Example 12. [Diagram 30] 13A and 13B are diagrams illustrating a cross-sectional view and a movement locus of a zoom lens according to a thirteenth embodiment. [Diagram 31] 23A to 23C are diagrams showing various aberrations of the zoom lens of Example 13. [Diagram 32] FIG. 13 is a cross-sectional view of the configuration of a zoom lens according to Example 13-1. [Diagram 33] 13A to 13C are diagrams showing various aberrations of the zoom lens of Example 13-1. [Diagram 34] 13A and 13B are diagrams illustrating a cross-sectional view of the configuration of a zoom lens according to a fourteenth embodiment and a movement locus thereof. [Diagram 35] 23A to 23C are diagrams showing various aberrations of the zoom lens of Example 14. [Diagram 36] FIG. 14 is a cross-sectional view of the configuration of a zoom lens according to Example 14-1. [Figure 37] 14A to 14C are diagrams showing various aberrations of the zoom lens of Example 14-1. [Figure 38] 15A and 15B are diagrams illustrating a cross-sectional view of the configuration of a zoom lens according to a fifteenth embodiment and a movement locus thereof. [Figure 39] 23A to 23C are diagrams showing various aberrations of the zoom lens of Example 15. [Diagram 40] FIG. 15 is a cross-sectional view of the configuration of a zoom lens according to Example 15-1. [Diagram 41] 15A to 15C are diagrams showing various aberrations of the zoom lens of Example 15-1. [Diagram 42] 23A and 23B are diagrams showing a cross-sectional view and a movement locus of a zoom lens according to a sixteenth embodiment. [Diagram 43] 23A to 23C are diagrams showing various aberrations of the zoom lens of Example 16. [Diagram 44] FIG. 16 is a cross-sectional view of a zoom lens configuration according to Example 16-1. [Diagram 45] 16A to 16C are diagrams showing various aberrations of the zoom lens of Example 16-1. [Figure 46] 23A and 23B are diagrams showing a cross-sectional view and a movement locus of a zoom lens according to a seventeenth embodiment. [Figure 47] 21A to 21C are diagrams showing various aberrations of the zoom lens of Example 17. [Figure 48] 23A and 23B are diagrams showing a cross-sectional view and a movement locus of a zoom lens according to an eighteenth embodiment. [Figure 49] 23A to 23C are diagrams showing various aberrations of the zoom lens of Example 18. [Figure 50] 23A and 23B are diagrams showing a cross-sectional view and a movement locus of a zoom lens according to a nineteenth embodiment. [Figure 51] 23A to 23C are diagrams showing various aberrations of the zoom lens of Example 19. [Figure 52] FIG. 19 is a cross-sectional view of the configuration of a zoom lens according to Example 19-1. [Diagram 53] 19A to 19C are diagrams showing various aberrations of the zoom lens of Example 19-1. [Figure 54] 1 is a schematic diagram illustrating the configuration of an imaging device according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0039] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[0040] 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 of a light beam. FIG. 2 shows a cross-sectional view of the configuration of the zoom lens in FIG. 1. In FIG. 1 and FIG. 2, a state in which an object at infinity is focused is shown, with the left side being the object side and the right side being the image side. In FIG. 1 and FIG. 2, the upper row labeled "Wide" shows the wide-angle end state, and the lower row labeled "Tele" shows the telephoto end state. In FIG. 1, the axial light beam and the light beam with the maximum half angle of view ωw at the wide-angle end, and the axial light beam and the light beam with the maximum half angle of view ωt at the telephoto end are shown as light beams. The examples shown in FIG. 1 and FIG. 2 correspond to the zoom lens of Example 1 described later. The following description will be mainly made with reference to FIG. 1, and FIG. 2 will be referred to as necessary.

[0041] In Fig. 1, assuming that the zoom lens is applied to an imaging device, an example is shown in which a parallel plate-like optical member PP is disposed between the zoom lens and an image surface Sim. The optical member PP is a member assuming various filters and / or cover glass, etc. The various filters are low-pass filters, infrared cut filters, and / or filters that cut off specific wavelength ranges, etc. The optical member PP is a member that does not have refractive power. It is also possible to configure an imaging device without the optical member PP.

[0042] The zoom lens of the present disclosure includes a first lens group G1 having positive refractive power and arranged closest to the object side, a negative lens group UN arranged adjacent to the image side of the first lens group G1 and having negative refractive power overall, an N lens group GN having negative refractive power arranged closer to the image side than the negative group UN, a P lens group GP having positive refractive power arranged closer to the image side than the negative group UN, and a final lens group GE arranged closest to the image side. The negative group UN is composed of two or less lens groups. When zooming, all the intervals between adjacent lens groups change. The above configuration makes it possible to obtain a wide image circle while maintaining the zoom ratio, and is advantageous in achieving compactness while ensuring a wide angle of view.

[0043] In this specification, a group whose distance in the optical axis direction between adjacent groups changes during magnification is defined as one lens group. During magnification, the distance between adjacent lenses in one lens group does not change. In this specification, each of the "lens groups" included in the "first lens group G1", "N lens group GN", "P lens group GP", "final lens group GE", and negative group UN is a component part of a zoom lens, and is a part including at least one lens, which is divided by an air gap that changes during magnification. During magnification, each lens group is moved or fixed, and the mutual distance between the lenses in each lens group does not change. The "lens group" may include a component other than a lens that does not have refractive power, such as an aperture stop St.

[0044] As an example, the zoom lens in FIG. 1 comprises, in order from the object side to the image side, a first lens group G1, a negative group UN consisting of one lens group, an N lens group GN, a P lens group GP, and a final lens group GE.

[0045] In the example of FIG. 1, each group is configured as follows. The first lens group G1 is composed of, in order from the object side to the image side, a negative lens, a positive lens, a positive lens, a positive lens, and a positive lens. The negative group UN is composed of, in order from the object side to the image side, a negative lens, a positive lens, and a negative lens. The N lens group GN is composed of, in order from the object side to the image side, a positive lens and a negative lens. The P lens group GP is composed of, in order from the object side to the image side, a positive lens, a negative lens, and a positive lens. The final lens group GE is composed of, in order from the object side to the image side, an aperture stop St, a positive lens, a negative lens, a positive lens, a negative lens, a positive lens, a negative lens, a positive lens, a negative lens, a positive lens, and a positive lens. Note that the aperture stop St in FIG. 1 does not indicate the shape or size, but indicates the position in the optical axis direction.

[0046] In the example of Fig. 1, during magnification change, the first lens group G1 and the final lens group GE are fixed with respect to the image plane Sim, and the negative lens group UN, the N lens group GN, and the P lens group GP move along the optical axis Z while changing the spacing between adjacent lens groups. In Fig. 1, the schematic movement trajectory of each lens group that moves during magnification change from the wide-angle end to the telephoto end is indicated by solid arrows between the upper and lower rows.

[0047] In the zoom lens of the present disclosure, it is preferable that the first lens group G1 is fixed relative to the image plane Sim during zooming, which can suppress movement of the center of gravity during zooming.

[0048] Furthermore, it is preferable that the final lens group GE is fixed relative to the image plane Sim during zooming, which makes it easier to suppress fluctuations in the F-number during zooming.

[0049] When changing magnification from the wide-angle end to the telephoto end, it is preferable for the N lens group GN to move along a locus that is convex toward the object side. This is advantageous for suppressing aberrations at intermediate focal lengths. As an example, the solid arrow showing the movement locus of the N lens group GN in Figure 1 is a curve that is convex toward the object side.

[0050] In the zoom lens of the present disclosure, it is preferable that the lens closest to the object side of the zoom lens is a negative lens. In this case, it is advantageous for suppressing lateral chromatic aberration. In addition, it is preferable that the second lens from the object side of the zoom lens is a positive lens. In this case, it is advantageous for suppressing axial chromatic aberration.

[0051] It is preferable that the first lens group G1 includes, in succession from the object side to the image side, a negative lens, a positive lens, and a positive lens, which is advantageous for suppressing axial chromatic aberration and lateral chromatic aberration.

[0052] It is preferable that the first lens group G1 includes one negative lens and four or more positive lenses, which is advantageous for suppressing chromatic aberration at the telephoto end.

[0053] It is preferable that the negative group UN includes an aspheric lens having at least one surface whose absolute value of the radius of curvature at the position of the maximum effective diameter is smaller than the absolute value of the paraxial radius of curvature, which is advantageous for suppressing astigmatism.

[0054] FIG. 3 shows an example of the position of the maximum effective diameter as an explanatory diagram. In FIG. 3, the left side is the object side, and the right side is the image side. FIG. 3 shows an axial light beam Xa and an off-axis light beam Xb passing through the lens Lx. In the example of FIG. 3, the light beam Xb1, which is the upper light beam of the off-axis light beam Xb, is the light beam that passes through the outermost side. In this specification, the distance from the intersection point of the outermost light beam and the lens surface among the light beams that enter the lens surface from the object side and exit to the image side to the optical axis Z is defined as the "effective radius" of the lens surface. And, the "effective diameter" is twice the effective radius. The "outside" here means the radial outside centered on the optical axis Z, that is, 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 intersection point of the object side surface of the lens Lx and the light beam Xb1 to the optical axis Z. And, the position Px of the intersection point of the outermost light beam and the lens surface is the position of the maximum effective diameter. In the example of Figure 3, the upper ray of the off-axis light beam Xb is the outermost ray, but which ray is the outermost ray varies depending on the optical system. The outermost ray is determined taking into consideration the entire range of magnification.

[0055] In the zoom lens of the present disclosure, it is preferable that the N lens group GN includes, in succession from the most object side to the image side, a positive lens and a negative lens, which is advantageous in suppressing fluctuations in axial chromatic aberration during magnification change.

[0056] It is preferable to dispose the P lens group GP adjacent to the image side of the N lens group GN, which is advantageous for achieving a wide angle.

[0057] The lens surface of the P lens group GP closest to the image side may be configured to be concave, which is advantageous in suppressing fluctuations in spherical aberration during magnification change.

[0058] It is preferable that the P lens group GP includes at least one aspheric lens having a surface whose absolute value of the radius of curvature at the position of the maximum effective diameter is larger than the absolute value of the paraxial radius of curvature, which is advantageous in suppressing the fluctuation of spherical aberration during magnification change.

[0059] It is preferable that the final lens group GE is disposed adjacent to the image side of the P lens group GP, which is advantageous for size reduction.

[0060] The lens closest to the image side of the final lens group GE may be configured to be a single lens having a positive refractive power. In this case, a lens system with a smaller F-number can be obtained. In this specification, the term "single lens" refers to a single lens that is not cemented.

[0061] A configuration may be adopted in which a part of the first lens group G1 moves along the optical axis Z during focusing. That is, a configuration may be adopted in which focusing is performed by a part of the first lens group G1 moving along the optical axis Z. In this case, when photographing an object at a finite distance, fluctuations in the focus position caused by magnification change can be suppressed. Hereinafter, the group that moves along the optical axis Z during focusing is referred to as the focusing group. Focusing is performed by moving the focusing group.

[0062] The first lens group G1 may be configured to include at least the 1a subgroup G1a, the 1b subgroup G1b, and the 1c subgroup G1c, in that order from the most object side to the image side, and the distance between the 1a subgroup G1a and the 1b subgroup G1b and the distance between the 1b subgroup G1b and the 1c subgroup G1c may be changed during focusing. In this case, it is advantageous for suppressing aberration fluctuation during focusing.

[0063] When the first lens group G1 includes at least the above-mentioned 1a sub-group G1a, 1b sub-group G1b, and 1c sub-group G1c, it is preferable that the 1a sub-group G1a includes an aspheric lens having at least one surface whose absolute value of the radius of curvature at the maximum effective diameter is larger than the absolute value of the paraxial radius of curvature, which is advantageous for suppressing spherical aberration at the telephoto end.

[0064] When the first lens group G1 includes at least the above-mentioned 1a sub-group G1a, 1b sub-group G1b, and 1c sub-group G1c, it is preferable that the 1c sub-group G1c includes an aspheric lens having at least one surface whose absolute value of the radius of curvature at the position of the maximum effective diameter is larger than the absolute value of the paraxial radius of curvature. In this case, it is advantageous to suppress the fluctuation of spherical aberration during focusing.

[0065] The first lens group G1 may be configured to be composed of a 1a subgroup G1a, a 1b subgroup G1b, and a 1c subgroup G1c in order from the object side to the image side, and the 1a subgroup G1a may be fixed with respect to the image plane Sim, and the 1b subgroup G1b and the 1c subgroup G1c may be configured to move along different trajectories during focusing. By configuring the first lens group G1 to be composed of three subgroups separated by intervals that change during focusing, it is advantageous to suppress aberration fluctuations during focusing while simplifying the drive mechanism. In addition, by moving the 1b subgroup G1b and the 1c subgroup G1c along different trajectories during focusing, it is advantageous to suppress aberration fluctuations during focusing. Note that "the 1b subgroup G1b and the 1c subgroup G1c move along different trajectories" is synonymous with the 1b subgroup G1b and the 1c subgroup G1c moving while changing the mutual interval.

[0066] When the first lens group G1 is composed of the above-mentioned 1a subgroup G1a, 1b subgroup G1b, and 1c subgroup G1c, the 1b subgroup G1b when focused on the closest object may be configured to be located closer to the object side than the 1b subgroup G1b when focused on an object at infinity. In this case, focusing on a closer object is possible.

[0067] Alternatively, when the first lens group G1 is composed of the above-mentioned 1a sub-group G1a, 1b sub-group G1b, and 1c sub-group G1c, the 1b sub-group G1b in a state focused on a nearest object may be configured to be located closer to the image side than the 1b sub-group G1b in a state focused on an object at infinity. In this case, it is advantageous for suppressing the fluctuation of the angle of view during focusing.

[0068] As an example, the first lens group G1 in the example of FIG. 1 is composed of a 1a subgroup G1a, a 1b subgroup G1b, and a 1c subgroup G1c in order from the object side to the image side, and when focusing from an object at infinity to a nearest object, the 1a subgroup G1a is fixed with respect to the image plane Sim, and the 1b subgroup G1b and the 1c subgroup G1c move toward the object side along different trajectories. That is, the zoom lens in the example of FIG. 1 includes two focusing groups, the 1b subgroup G1b and the 1c subgroup G1c, and when focusing, these two focusing groups move toward the object side while changing the mutual distance. In FIG. 1, arrows indicating the direction of movement when focusing from an object at infinity to a nearest object are written under each focusing group in the lower diagram. Although each focusing group functions over the entire range of magnification including the wide-angle end state, the above arrows are written only in the lower diagram in FIG. 1 to avoid the diagram from becoming too complicated.

[0069] In the zoom lens of the present disclosure, as shown in the examples described later, the first lens group G1 may be configured to be composed of, in order from the object side to the image side, the 1a subgroup G1a, the 1b subgroup G1b, the 1c subgroup G1c, and the 1d subgroup G1d, and may be configured such that, during focusing, the distance between the 1a subgroup G1a and the 1b subgroup G1b changes, the distance between the 1b subgroup G1b and the 1c subgroup G1c changes, and the distance between the 1c subgroup G1c and the 1d subgroup G1d changes. In this case, it is advantageous to suppress aberration fluctuation during focusing.

[0070] When the first lens group G1 is composed of the above-mentioned 1a sub-group G1a, 1b sub-group G1b, 1c sub-group G1c, and 1d sub-group G1d, the 1a sub-group G1a and 1c sub-group G1c may be fixed relative to the image plane Sim, and the 1b sub-group G1b and 1d sub-group G1d may move along different trajectories during focusing. In this case, it is advantageous for suppressing aberration fluctuations during focusing while simplifying the driving mechanism.

[0071] Alternatively, when the first lens group G1 is composed of the above-mentioned 1a sub-group G1a, 1b sub-group G1b, 1c sub-group G1c, and 1d sub-group G1d, the 1a sub-group G1a may be fixed relative to the image plane Sim during focusing, and the 1b sub-group G1b, 1c sub-group G1c, and 1d sub-group G1d may move along different trajectories. In this case, it is advantageous to suppress aberration fluctuation during focusing.

[0072] When the first lens group G1 is composed of the above-mentioned 1a sub-group G1a, 1b sub-group G1b, 1c sub-group G1c, and 1d sub-group G1d, the 1b sub-group G1b in the state of focusing on the nearest object may be configured to be located closer to the image side than the 1b sub-group G1b in the state of focusing on the infinite object. In this case, it is advantageous to suppress the fluctuation of the angle of view during focusing.

[0073] Next, preferred and possible configurations for the conditional expressions of the zoom lens of the present disclosure will be described. In the following description of the conditional expressions, in order to avoid redundant explanations, the same symbols are used for elements with the same definitions, and some of the duplicated explanations of the symbols are omitted. In addition, in the following, in order to avoid redundant explanations, the "zoom lens of the present disclosure" will also be simply referred to as the "zoom lens."

[0074] If the focal length of the N lens group GN is fN and the focal length of the first lens group G1 is f1, it is preferable that the zoom lens satisfies the following conditional formula (1). By ensuring that the corresponding value of conditional formula (1) is not below the lower limit, the refractive power of the first lens group G1 can be suppressed, which is advantageous for suppressing aberration fluctuations during zooming. By ensuring that the corresponding value of conditional formula (1) is not above the upper limit, the refractive power of the N lens group GN can be suppressed, which is advantageous for suppressing aberration fluctuations during zooming. -6 <fN / f1<-0.55 (1)

[0075] In order to obtain better characteristics, the lower limit of conditional formula (1) is more preferably -3, even more preferably -2.5, even more preferably -2, and even more preferably -1.75.In order to obtain better characteristics, the upper limit of conditional formula (1) is more preferably -1.07, even more preferably -1.08, even more preferably -1.09, and even more preferably -1.1.

[0076] It is preferable that the zoom lens satisfies the following conditional expression (2). Here, Denw is the distance on the optical axis from the lens surface closest to the object of the first lens group G1 to the paraxial entrance pupil position when the zoom lens is focused on an object at infinity at the wide-angle end. fw is the focal length of the zoom lens when the zoom lens is focused on an object at infinity at the wide-angle end. As an example, FIG. 4 shows the above distance Denw. FIG. 4 shows a cross-sectional view of the configuration and light beam of the zoom lens of FIG. 1 when the zoom lens is focused on an object at infinity at the wide-angle end. By making the corresponding value of conditional expression (2) not equal to or less than the lower limit, the distance on the optical axis from the lens surface closest to the object of the first lens group G1 to the paraxial entrance pupil position at the wide-angle side can be increased, which is advantageous in suppressing the variation of the field curvature during zooming. By ensuring that the corresponding value of conditional formula (2) is not equal to or greater than the upper limit, it is possible to shorten the distance on the optical axis from the lens surface in the first lens group G1 closest to the object to the paraxial entrance pupil position on the wide-angle side, which is advantageous for widening the angle of view. 1.2 <Denw / fw<8 (2)

[0077] In order to obtain better characteristics, the lower limit of conditional formula (2) is more preferably 2.7, even more preferably 2.75, even more preferably 2.8, and even more preferably 2.85.In order to obtain better characteristics, the upper limit of conditional formula (2) is more preferably 4, even more preferably 3.8, even more preferably 3.6, and even more preferably 3.4.

[0078] If the focal length of the negative group UN is fUN and the focal length of the N lens group GN is fN, it is preferable that the zoom lens satisfies the following conditional expression (3). By ensuring that the corresponding value of conditional expression (3) is not below the lower limit, the refractive power of the negative group UN can be suppressed, which is advantageous for suppressing aberration fluctuations during zooming. By ensuring that the corresponding value of conditional expression (3) is not above the upper limit, the refractive power of the N lens group GN can be suppressed, which is advantageous for suppressing aberration fluctuations during zooming. 0.118 <fUN / fN<0.25 (3)

[0079] In order to obtain better characteristics, the lower limit of conditional expression (3) should preferably be 0.125, more preferably 0.133, and even more preferably 0.143. In order to obtain better characteristics, the upper limit of conditional expression (3) should preferably be 0.22, more preferably 0.2, and even more preferably 0.19.

[0080] In a configuration in which the first lens group G1 includes at least the 1a sub-group G1a and the 1b sub-group G1b in succession from the most object side to the image side, and the distance between the 1a sub-group G1a and the 1b sub-group G1b changes during focusing, it is preferable that the zoom lens satisfies the following conditional expression (4). Here, the focal length of the 1a sub-group G1a is f1a. By making sure that the corresponding value of the conditional expression (4) is not equal to or less than the lower limit, the degree of divergence of the axial light beam by the 1a sub-group G1a can be weakened, which is advantageous for making the diameter of the 1b sub-group G1b smaller. By ensuring that the corresponding value of conditional expression (4) is not equal to or greater than the upper limit value, the refractive power of the 1a subgroup G1a can be weakened, and therefore, by strengthening the positive refractive power of the 1b subgroup G1b and the side closer to the image than the 1b subgroup G1b, the amount of change in the spacing during focusing can be reduced, which is advantageous for shortening the overall length of the lens system. -0.85 <f1 / f1a<0.15 (4)

[0081] In order to obtain better characteristics, the lower limit of conditional expression (4) is preferably set to -0.4, more preferably to -0.1, and even more preferably to -0.008.In order to obtain better characteristics, the upper limit of conditional expression (4) is preferably set to 0.1, more preferably to 0.08, and even more preferably to 0.048.

[0082] It is preferable that the zoom lens satisfies the following conditional expression (5). By making sure that the corresponding value of conditional expression (5) is not below the lower limit, the refractive power of the negative group UN can be strengthened, and the amount of movement of the negative group UN during zooming can be reduced, which is advantageous for shortening the overall length of the lens system. By making sure that the corresponding value of conditional expression (5) is not above the upper limit, the refractive power of the first lens group G1 can be strengthened, which is advantageous for making the negative group UN smaller in diameter and lighter in weight. -0.4 <fUN / f1<-0.09 (5)

[0083] In order to obtain better characteristics, the lower limit of condition (5) should preferably be set to -0.33, more preferably to -0.28, and even more preferably to -0.245.In order to obtain better characteristics, the upper limit of condition (5) should preferably be set to -0.12, more preferably to -0.16, and even more preferably to -0.19.

[0084] 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 refractive power of the first lens group G1 can be strengthened, which is advantageous for shortening the overall length of the lens system. By ensuring that the corresponding value of conditional expression (6) is not equal to or greater than the upper limit, the entrance pupil position can be positioned closer to the object side, which is advantageous for reducing the diameter of the first lens group G1. 0.4 <Denw / f1<1.6 (6)

[0085] In order to obtain better characteristics, the lower limit of conditional formula (6) should preferably be 0.5, more preferably 0.6, and even more preferably 0.67. In order to obtain better characteristics, the upper limit of conditional formula (6) should preferably be 1.4, more preferably 1.2, and even more preferably 1.

[0086] It is preferable that the zoom lens satisfies the following conditional expression (7). Here, the maximum image height when focused on an object at infinity at the wide-angle end is IHw. As an example, the above-mentioned maximum image height IHw is shown in FIG. 1. By making the corresponding value of conditional expression (7) not equal to or less than the lower limit, the distance on the optical axis from the lens surface of the first lens group G1 closest to the object on the wide-angle side to the paraxial entrance pupil position can be increased, which is advantageous for suppressing the variation of the field curvature during zooming. By making the corresponding value of conditional expression (7) not equal to or more than the upper limit, the distance on the optical axis from the lens surface of the first lens group G1 closest to the object on the wide-angle side to the paraxial entrance pupil position can be shortened, which is advantageous for widening the angle. 3.4 <Denw / IHw<7.5 (7)

[0087] In order to obtain better characteristics, the lower limit of conditional formula (7) should more preferably be 3.7, even more preferably be 3.9, and even more preferably be 4.2.In order to obtain better characteristics, the upper limit of conditional formula (7) should more preferably be 6.2, even more preferably be 5.6, and even more preferably be 5.59.

[0088] It is preferable that the zoom lens satisfies the following conditional expression (8). Here, the displacement amount of the N lens group GN in the optical axis direction during zooming from the wide-angle end to the telephoto end is MovN. The focal length of the zoom lens in a state where an object at infinity is focused at the telephoto end is ft. The focal length of the zoom lens in a state where an object at infinity is focused at the wide-angle end is fw. The sign of the above displacement amount MovN is negative when the N lens group GN moves toward the object side, and positive when it moves toward the image side. As an example, the above displacement amount MovN is shown in FIG. 2. The displacement amount MovN is the difference between the position of the N lens group GN in the optical axis direction at the wide-angle end and the position of the N lens group GN in the optical axis direction at the telephoto end, and the reference of each position is the position of the image surface Sim. By making the corresponding value of conditional expression (8) not equal to or less than the lower limit, a space for the negative group UN to move toward the object side at the telephoto end can be secured, which is advantageous for achieving a high zoom ratio. By ensuring that the corresponding value of conditional expression (8) is not equal to or greater than the upper limit, the N lens group GN can be positioned closer to the object side at the telephoto end, which is advantageous for correcting off-axis aberrations at the telephoto end. -0.4 <MovN / (f1 / log(ft / fw))<0.1 (8)

[0089] In order to obtain better characteristics, the lower limit of condition (8) should preferably be set to -0.35, more preferably to -0.3, and even more preferably to -0.24.In order to obtain better characteristics, the upper limit of condition (8) should preferably be set to 0.05, more preferably to 0.01, and even more preferably to -0.03.

[0090] It is preferable that the zoom lens satisfies the following conditional expression (9). Here, the back focus in the air equivalent distance when focused on an object at infinity at the wide-angle end is Bfw. By ensuring that the corresponding value of conditional expression (9) is not equal to or less than the lower limit, it is advantageous for ensuring the amount of peripheral light. By ensuring that the corresponding value of conditional expression (9) is not equal to or more than the upper limit, it is advantageous for shortening the overall length of the lens system. 1.9 <Bfw / IHw<6 (9)

[0091] In order to obtain better characteristics, the lower limit of conditional formula (9) should more preferably be 2.2, even more preferably be 2.45, and even more preferably be 2.75.In order to obtain better characteristics, the upper limit of conditional formula (9) should more preferably be 5, even more preferably be 4.4, and even more preferably be 3.9.

[0092] It is preferable that the zoom lens satisfies the following conditional expression (10). Here, the longest air gap among the air gaps on the optical axis included in the lens surface closest to the object of the P lens group GP to the lens surface closest to the image of the final lens group GE when focused on an object at infinity at the wide-angle end is defined as the maximum air gap DAmax. The Petzval sum from the lens surface closest to the object of the first lens group G1 to the object-side surface that constitutes the above maximum air gap DAmax is defined as PF. As an example, FIG. 4 shows the above maximum air gap DAmax. In the example of FIG. 4, the maximum air gap DAmax is constituted by the image-side surface of the second lens from the object side of the final lens group and the object-side surface of the third lens from the object side of the final lens group. By making the corresponding value of conditional expression (10) not equal to or less than the lower limit, it is possible to suppress overcorrection of the field curvature. By making the corresponding value of conditional expression (10) not equal to or more than the upper limit, it is advantageous to suppress the field curvature that occurs on the object side of the image-side surface that constitutes the above maximum air gap DAmax. 0.12 <PF×IHw<0.25 (10)

[0093] In order to obtain better characteristics, the lower limit of condition (10) should preferably be 0.13, more preferably 0.149, and even more preferably 0.165.In order to obtain better characteristics, the upper limit of condition (10) should preferably be 0.21, more preferably 0.203, and even more preferably 0.185.

[0094] The Petzval sum PZ from the Sa plane to the Sb plane is defined by the following formula.

number

[0095] 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 satisfies the following conditional expression (11). Here, the unit of ωw is degrees. Making sure that the corresponding value of conditional expression (11) is not equal to or smaller than the lower limit value is advantageous for achieving a wider angle. Making sure that the corresponding value of conditional expression (11) is not equal to or larger than the upper limit value is advantageous for achieving compactness. 21<ωw<55 (11)

[0096] In order to obtain better characteristics, it is more preferable that the lower limit of conditional formula (11) be set to 24, even more preferably to 27, and even more preferably to 30. In order to obtain better characteristics, it is more preferable that the upper limit of conditional formula (11) be set to 50, even more preferably to 45, and even more preferably to 41.

[0097] It is preferable that the zoom lens satisfies the following conditional expression (12). By making sure that the corresponding value of conditional expression (12) is not equal to or less than the lower limit, it is advantageous for suppressing aberration fluctuations during zooming. By making sure that the corresponding value of conditional expression (12) is not equal to or greater than the upper limit, it is advantageous for achieving a high zoom ratio. 0.06 <fw / ft<0.13 (12)

[0098] In order to obtain better characteristics, the lower limit of conditional expression (12) should preferably be set to 0.065, more preferably to 0.07, and even more preferably to 0.075.In order to obtain better characteristics, the upper limit of conditional expression (12) should preferably be set to 0.12, more preferably to 0.11, and even more preferably to 0.105.

[0099] It is preferable that the zoom lens satisfies the following conditional expression (13). Here, the distance on the optical axis from the paraxial exit pupil position to the image plane Sim in a state where an object at infinity is focused at the wide-angle end is set to Dexw. However, when an optical member without refractive power is disposed between the paraxial exit pupil position and the image plane Sim, the air-equivalent distance is used to calculate Dexw for that optical member. As an example, FIG. 4 shows the above-mentioned distance Dexw in a schematic manner. In FIG. 4, a parallel plate-like optical member without refractive power that should be calculated using the air-equivalent distance is shown by a broken line. By making the corresponding value of conditional expression (13) not equal to or less than the lower limit, the total length of the lens system can be shortened, which is advantageous for miniaturization. By making the corresponding value of conditional expression (13) not equal to or more than the upper limit, the angle of incidence of the off-axis chief ray on the image plane Sim can be reduced, which is advantageous for ensuring the amount of peripheral light. 0.025 <IHw / Dexw<0.15 (13)

[0100] In order to obtain better characteristics, the lower limit of conditional expression (13) should preferably be 0.04, more preferably 0.05, and even more preferably 0.075.In order to obtain better characteristics, the upper limit of conditional expression (13) should preferably be 0.14, more preferably 0.13, and even more preferably 0.11.

[0101] It is preferable that the zoom lens satisfies the following conditional expression (14). By making sure that the corresponding value of conditional expression (14) is not below the lower limit, the refractive power of the first lens group G1 can be made strong, which is advantageous for shortening the overall length of the lens system. By making sure that the corresponding value of conditional expression (14) is not above the upper limit, the refractive power of the first lens group G1 does not become too strong, which is advantageous for achieving a wide angle while suppressing aberrations. 0.08 <fw / f1<0.5 (14)

[0102] In order to obtain better characteristics, the lower limit of conditional formula (14) should preferably be 0.12, more preferably 0.17, and even more preferably 0.22.In order to obtain better characteristics, the upper limit of conditional formula (14) should preferably be 0.4, more preferably 0.35, and even more preferably 0.32.

[0103] It is preferable that the zoom lens satisfies the following conditional expression (15). By making sure that the corresponding value of conditional expression (15) is not below the lower limit, the refractive power of the negative group UN does not become too strong, which is advantageous for suppressing aberration fluctuations during zooming. By making sure that the corresponding value of conditional expression (15) is not above the upper limit, the refractive power of the negative group UN does not become too weak, which is advantageous for size reduction. -2.4 <fw / fUN<-0.6 (15)

[0104] In order to obtain better characteristics, it is more preferable that the lower limit of conditional formula (15) be set to -2, more preferably -1.7, and even more preferably -1.4.In order to obtain better characteristics, it is more preferable that the upper limit of conditional formula (15) be set to -0.8, more preferably -1, and even more preferably -1.3.

[0105] It is preferable that the zoom lens satisfies the following conditional expression (16). Here, the paraxial radius of curvature of the image side surface of the lens closest to the object of the zoom lens is R2. The paraxial radius of curvature of the object side surface of the second lens from the object side of the zoom lens is R3. By making the corresponding value of conditional expression (16) not smaller than the lower limit, the refractive power of the air lens formed between the lens closest to the object of the zoom lens and the second lens from the object side of the zoom lens can be shifted to a negative refractive power, which is advantageous for suppressing distortion aberration. By making the corresponding value of conditional expression (16) not larger than the upper limit, the absolute value of the radius of curvature of the image side surface of the lens closest to the object of the zoom lens does not become too small, which is advantageous for suppressing ghosts. -0.25<(R2-R3) / (R2+R3)<0.16 (16)

[0106] In order to obtain better characteristics, the lower limit of condition (16) should preferably be set to -0.18, more preferably to -0.15, and even more preferably to -0.13.In order to obtain better characteristics, the upper limit of condition (16) should preferably be set to 0.12, more preferably to 0.08, and even more preferably to 0.04.

[0107] It is preferable that the zoom lens satisfies the following conditional expression (17). Here, when focused on an object at infinity at the wide-angle end, the composite lateral magnification of all lenses on the image side of the maximum air spacing DAmax is set to βAmaxR. Ensuring that the corresponding value of conditional expression (17) is not equal to or less than the lower limit thereof is advantageous for reducing the diameter of the group consisting of all lenses on the image side of the maximum air spacing DAmax. Ensuring that the corresponding value of conditional expression (17) is not equal to or greater than the upper limit thereof is advantageous for suppressing aberration fluctuations when the maximum air spacing DAmax changes due to an error. -0.05<βAmaxR<0.45 (17)

[0108] In order to obtain better characteristics, it is more preferable that the lower limit of conditional formula (17) be 0, even more preferably 0.05, and even more preferably 0.09. In order to obtain better characteristics, it is more preferable that the upper limit of conditional formula (17) be 0.38, even more preferably 0.33, and even more preferably 0.26.

[0109] It is preferable that the zoom lens satisfies the following conditional expression (18). Here, the central thickness of the negative lens closest to the object among the negative lenses included in the negative group UN is tN1. The effective radius of the object-side surface of the negative lens closest to the object among the negative lenses included in the negative group UN is ErN1. As an example, FIG. 2 shows the central thickness tN1. By making sure that the corresponding value of conditional expression (18) is not equal to or less than the lower limit, it is advantageous to improve the robustness of the negative lens closest to the object among the negative lenses included in the negative group UN. By making sure that the corresponding value of conditional expression (18) is not equal to or more than the upper limit, it is advantageous to reduce weight. 0.015 <tN1 / ErN1<0.085 (18)

[0110] In order to obtain better characteristics, the lower limit of conditional formula (18) should more preferably be 0.025, even more preferably be 0.03, and even more preferably be 0.034.In order to obtain better characteristics, the upper limit of conditional formula (18) should more preferably be 0.075, even more preferably be 0.068, and even more preferably be 0.05.

[0111] It is preferable that the zoom lens satisfies the following conditional expression (19). Here, the displacement amount in the optical axis direction of the P lens group GP when changing the magnification from the wide-angle end to the telephoto end is MovP. The sign of the above displacement amount MovP is negative when the P lens group GP moves toward the object side, and positive when it moves toward the image side. As an example, the above displacement amount MovP is shown in FIG. 2. The displacement amount MovP is the difference between the position of the P lens group GP in the optical axis direction at the wide-angle end and the position of the P lens group GP in the optical axis direction at the telephoto end, based on the position of the image surface Sim. By making the corresponding value of the conditional expression (19) not equal to or less than the lower limit, the movement of the P lens group GP toward the object side can be suppressed, and the space for the group that moves during the magnification change other than the P lens group GP can be secured. This is advantageous for realizing a high zoom ratio while shortening the overall length of the lens system. By ensuring that the corresponding value of conditional expression (19) is not equal to or greater than the upper limit, the P lens group GP can be positioned closer to the object side at the telephoto end, which is advantageous in suppressing fluctuations in the focus position when varying magnification. -0.45 <MovP / (f1 / log(ft / fw))<0.1 (19)

[0112] In order to obtain better characteristics, the lower limit of condition (19) should preferably be set to -0.38, more preferably to -0.3, and even more preferably to -0.23.In order to obtain better characteristics, the upper limit of condition (19) should preferably be set to 0.05, more preferably to 0.001, and even more preferably to -0.03.

[0113] It is preferable that the zoom lens satisfies the following conditional expression (20). Here, D1a is the thickness on the optical axis of the group consisting of all lenses on the object side of the most object-side distance among the distances that change during focusing. TLw is the sum of the distance on the optical axis from the lens surface on the most object side of the first lens group G1 to the lens surface on the most image side of the final lens group GE when focused on an object at infinity at the wide-angle end, and the back focus in air equivalent distance. As an example, FIG. 2 shows the thickness D1a. By making the corresponding value of conditional expression (20) not equal to or less than the lower limit, it is advantageous for suppressing aberration fluctuations during focusing of the axial light beam at the telephoto end. By making the corresponding value of conditional expression (20) not equal to or more than the upper limit, it is advantageous for weight reduction. 0.019 <D1a / TLw<0.18 (20)

[0114] In order to obtain better characteristics, the lower limit of conditional formula (20) should more preferably be 0.025, even more preferably be 0.04, and even more preferably be 0.07.In order to obtain better characteristics, the upper limit of conditional formula (20) should more preferably be 0.16, even more preferably be 0.14, and even more preferably be 0.125.

[0115] It is preferable that the zoom lens satisfies the following conditional expression (21). Here, among the intervals that change during focusing, the axial thickness of the group consisting of all lenses between the interval closest to the object and the interval second from the object is defined as D1b. The axial thickness of the first lens group G1 is defined as DG1. As an example, the thicknesses D1b and DG1 are shown in FIG. 2. By ensuring that the corresponding value of conditional expression (21) is not equal to or less than the lower limit, it is advantageous for suppressing the variation of spherical aberration during focusing. By ensuring that the corresponding value of conditional expression (21) is not equal to or more than the upper limit, it is advantageous for weight reduction. 0.13 <D1b / DG1<0.45 (21)

[0116] In order to obtain better characteristics, the lower limit of conditional formula (21) should more preferably be 0.18, even more preferably be 0.22, and even more preferably be 0.26.In order to obtain better characteristics, the upper limit of conditional formula (21) should more preferably be 0.4, even more preferably be 0.35, and even more preferably be 0.3.

[0117] It is preferable that the zoom lens satisfies the following conditional expression (22). Here, gνmax is the specific gravity of the positive lens having the largest Abbe number based on the d-line among the positive lenses included in the first lens group G1. By ensuring that the corresponding value of conditional expression (22) is not equal to or less than the lower limit, the selectivity of materials having anomalous dispersion increases, which is advantageous for correcting axial chromatic aberration. By ensuring that the corresponding value of conditional expression (22) is not equal to or greater than the upper limit, which is advantageous for reducing weight. 3.1 <gνmax<4.2 (22)

[0118] In order to obtain better characteristics, it is more preferable that the lower limit of conditional formula (22) be set to 3.2, even more preferably to 3.3, and even more preferably to 3.4.In order to obtain better characteristics, it is more preferable that the upper limit of conditional formula (22) be set to 4, even more preferably to 3.8, and even more preferably to 3.6.

[0119] It is preferable that the zoom lens satisfies the following conditional expression (23). Here, the central thickness of the lens closest to the object in the first lens group G1 is tL1. The effective radius of the object-side surface of the lens closest to the object in the first lens group G1 is ErL1. As an example, FIG. 2 shows the central thickness tL1. By ensuring that the corresponding value of conditional expression (23) is not equal to or less than the lower limit, it is advantageous for improving the robustness of the lens closest to the object in the first lens group G1. By ensuring that the corresponding value of conditional expression (23) is not equal to or more than the upper limit, it is advantageous for weight reduction. 0.025 <tL1 / ErL1<0.075 (23)

[0120] In order to obtain better characteristics, the lower limit of conditional formula (23) should more preferably be 0.03, even more preferably be 0.034, and even more preferably be 0.038.In order to obtain better characteristics, the upper limit of conditional formula (23) should more preferably be 0.065, even more preferably be 0.055, and even more preferably be 0.046.

[0121] The zoom lens of the present disclosure may be configured to include an EX group EX that changes the focal length of the zoom lens by being inserted into or removed from the optical path. For example, the EX group EX that changes the focal length of the zoom lens while keeping the image formation position constant by being inserted into the optical path of the above-mentioned longest air gap DAmax may be arranged so as to be insertable and removable. In this case, a zoom lens with a variable focal length can be obtained.

[0122] As an example, the EX group EX is shown in FIG. 4. The EX group EX in FIG. 4 is composed of seven lenses. FIG. 5 shows a cross-sectional view of the configuration of the zoom lens and the light beam when the EX group EX in FIG. 4 is inserted into the zoom lens in FIG. 1 as Example 1-1. The final lens group GEE in FIG. 5 is configured such that the EX group EX is inserted inside the final lens group GE in FIG. 1, and in this respect the example in FIG. 5 differs from the example in FIG. 1. The configuration of the other lens groups and groups in the example in FIG. 5 is the same as that in the example in FIG. 1. FIG. 5 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. In FIG. 5, the upper row labeled "Wide" shows the wide-angle end state, and the lower row labeled "Tele" shows the telephoto end state. In FIG. 5, the axial light beam and the light beam with the maximum half angle of view ωEw at the wide-angle end, and the axial light beam and the light beam with the maximum half angle of view ωEt at the telephoto end are shown as the light beams. In FIG. 5, the reference symbols for the 1a sub-group G1a, the 1b sub-group G1b, and the 1c sub-group G1c, as well as the arrows indicating the movement directions during focusing, are omitted.

[0123] When the zoom lens includes the EX group EX, the maximum image height may be changed by inserting or removing the EX group EX. For example, in the wide-angle end state, the maximum image height IHEw in the example shown in Fig. 5 is enlarged compared to the maximum image height IHw in the example shown in Fig. 1. By configuring in this way, it is possible to obtain a zoom lens having a wider image circle while maintaining the angle of view.

[0124] It is preferable that the zoom lens satisfies the following conditional expression (24). Here, the focal length of the zoom lens when the EX group EX is not inserted and the zoom lens is focused on an object at infinity at the telephoto end is ft. The maximum half angle of view when the EX group EX is not inserted and the zoom lens is focused on an object at infinity at the telephoto end is ωt. The focal length of the zoom lens when the EX group EX is inserted and the zoom lens is focused on an object at infinity at the telephoto end is fEt. The maximum half angle of view when the EX group EX is inserted and the zoom lens is focused on an object at infinity at the telephoto end is ωEt. tan is the tangent. By making the corresponding value of the conditional expression (24) not equal to or less than the lower limit, it is easy to obtain the image size required when the EX group EX is inserted. By making the corresponding value of the conditional expression (24) not equal to or more than the upper limit, it is advantageous to simultaneously suppress various aberrations when the EX group EX is not inserted and various aberrations when the EX group EX is inserted. 0.5<(ft×tanωt) / (fEt×tanωEt)<0.9 (24)

[0125] In order to obtain better characteristics, the lower limit of conditional formula (24) should more preferably be 0.55, even more preferably be 0.6, and even more preferably be 0.65.In order to obtain better characteristics, the upper limit of conditional formula (24) should more preferably be 0.85, even more preferably be 0.8, and even more preferably be 0.75.

[0126] It is preferable for the zoom lens to satisfy the following conditional expression (25). Here, the thickness on the optical axis of the EX group EX is designated as DEX. As an example, the above thickness DEX is shown in FIG. 5. Ensuring that the corresponding value of conditional expression (25) is not below the lower limit value is advantageous for suppressing aberrations generated in the EX group EX. Ensuring that the corresponding value of conditional expression (25) is not above the upper limit value is advantageous for reducing the weight of the EX group EX. 0.05 <DEX / TLw<0.12 (25)

[0127] In order to obtain better characteristics, the lower limit of conditional formula (25) should more preferably be 0.06, even more preferably be 0.07, and even more preferably be 0.085.In order to obtain better characteristics, the upper limit of conditional formula (25) should more preferably be 0.11, even more preferably be 0.1, and even more preferably be 0.094.

[0128] It is preferable that the zoom lens satisfy the following conditional expression (26). Here, the focal length of the lens component closest to the image side in the EX group EX is fLExe. Note that one lens component means one single lens or one cemented lens. By ensuring that the corresponding value of conditional expression (26) is not equal to or less than the lower limit, it is possible to prevent the distortion occurring in the EX group EX from being over-corrected. By ensuring that the corresponding value of conditional expression (26) is not equal to or more than the upper limit, it is possible to correct the distortion occurring in the EX group EX. -2.3 <Bfw / fLExe<-0.55 (26)

[0129] In order to obtain better characteristics, it is more preferable that the lower limit of conditional formula (26) be set to -2.2, even more preferably to -2.1, and even more preferably to -1.98.In order to obtain better characteristics, it is more preferable that the upper limit of conditional formula (26) be set to -0.84, even more preferably to -1.1, and even more preferably to -1.75.

[0130] It is preferable for the zoom lens to satisfy the following conditional expression (27). Here, the refractive index at the d-line of the lens in the EX group EX closest to the object is set to NEX1. Ensuring that the corresponding value of conditional expression (27) is not below the lower limit value is advantageous for suppressing spherical aberration occurring in the EX group EX. Ensuring that the corresponding value of conditional expression (27) is not above the upper limit value is advantageous for suppressing longitudinal chromatic aberration occurring in the EX group EX. 1.4 <NEX1<1.85 (27)

[0131] In order to obtain better characteristics, it is more preferable that the lower limit of conditional formula (27) be set to 1.45, even more preferably to 1.5, and even more preferably to 1.56.In order to obtain better characteristics, it is more preferable that the upper limit of conditional formula (27) be set to 1.75, even more preferably to 1.7, and even more preferably to 1.65.

[0132] Note that the example shown in Fig. 1 is just one example, and various modifications are possible within the scope of the gist of the technology of the present disclosure. For example, the number of lenses included in the first lens group G1, the negative group UN, the N lens group GN, the P lens group GP, the final lens group GE, and each focusing group may be different from the example in Fig. 1. The number of lens groups included in the negative group UN may also be different from the example in Fig. 1. The focusing group, the position of the aperture stop St, and the lens groups that move during magnification may be configured differently from the example in Fig. 1.

[0133] The above-mentioned preferred and possible configurations can be arbitrarily combined within a range not causing any contradiction, and it is preferable that they are appropriately and selectively adopted according to the required specifications.

[0134] As an example, a preferred embodiment of the present disclosure is a zoom lens comprising a first lens group G1 having positive refractive power and arranged closest to the object, a negative group UN consisting of two or less lens groups and arranged adjacent to the image side of the first lens group G1 and having negative refractive power as a whole, an N lens group GN having negative refractive power and arranged closer to the image side than the negative group UN, a P lens group GP having positive refractive power and arranged closer to the image side than the negative group UN, and a final lens group GE arranged closest to the image side, wherein the spacing between all of the adjacent lens groups changes during magnification change, satisfying the above conditional formula (1).

[0135] Next, an embodiment of the zoom lens of the present disclosure will be described with reference to the drawings. The reference symbols attached to each group in the cross-sectional view of each embodiment are used independently for each embodiment to avoid the explanation and the drawings becoming complicated due to the increase in the number of digits of the reference symbols. Therefore, even if the same reference symbols are attached in the drawings of different embodiments, they do not necessarily have the same configuration.

[0136] [Example 1] The configuration and movement locus of the zoom lens of the first embodiment are shown in Fig. 1, and the method of illustration and the configuration are as described above, so some overlapping explanations will be omitted here. The zoom lens of the first embodiment is composed of, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a negative group UN having a negative refractive power as a whole, an N lens group GN having a negative refractive power, a P lens group GP having a positive refractive power, and a final lens group GE having a positive refractive power. The negative group UN is composed of one lens group.

[0137] When changing magnification from the wide-angle end to the telephoto end, the first lens group G1 and the final lens group GE are fixed with respect to the image plane Sim, and the negative lens group UN, the N lens group GN, and the P lens group GP move along the optical axis Z while changing the spacing between adjacent lens groups.

[0138] The first lens group G1 is composed of, in order from the object side to the image side, a 1a subgroup G1a, a 1b subgroup G1b, and a 1c subgroup G1c. When focusing from an object at infinity to a closest object, the 1a subgroup G1a is fixed with respect to the image plane Sim, and the 1b subgroup G1b and the 1c subgroup G1c move toward the object side while changing the mutual distance between them.

[0139] For the zoom lens of Example 1, basic lens data is shown in Table 1, specifications and variable surface spacing is shown in Table 2, and aspheric coefficients are shown in Table 3.

[0140] The basic lens data table is written as follows. The "Sn" column shows the surface numbers, with the surface closest to the object being surface 1 and the numbers increasing by one 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 "θg,F" column shows the partial dispersion ratio between the g-line and F-line of each component. The "SG" column shows the specific gravity of each component. The "ED" column shows the effective diameter of each surface.

[0141] 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 θg,F, then θg,F is defined by the following equation. θg,F=(Ng-NF) / (NF-NC)

[0142] The terms "d-line," "C-line," "F-line," and "g-line" used in this specification are emission lines, and the wavelength of the d-line is 587.56 nm (nanometers), the wavelength of the C-line is 656.27 nm (nanometers), the wavelength of the F-line is 486.13 nm (nanometers), and the wavelength of the g-line is 435.84 nm (nanometers).

[0143] In the basic lens data table, the sign of the radius of curvature of a surface with a convex shape facing the object side is positive, and the sign of the radius of curvature of a surface with a convex shape facing the image side is negative. Table 1 also shows the aperture stop St and optical member PP. In the column for the surface number of the surface corresponding to the aperture stop St, the surface number and the word (St) are entered. The value in the bottom row of the D column in the table is the distance between the surface in the table closest to the image side and the image plane Sim. The symbol DD[ ] is used for the variable surface distance, and the surface number on the object side of this distance is entered in [ ] in the D column.

[0144] Table 2 shows the zoom ratio Zr, focal length f, maximum open F-number FNo., maximum full angle of view 2ω, variable surface spacing, and maximum image height IHw when focused on an object at infinity at the wide-angle end, based on the d-line. The zoom ratio is synonymous with the zoom magnification. [°] in the 2ω column indicates that the unit is degrees. Table 2 shows values ​​for each object distance and each zoom state. More specifically, the "Infinity" column shows values ​​when focused on an object at infinity, the "Closest (0.88m)" column shows values ​​when focused on a close object, and the "Wide," "Middle," and "Tele" columns show values ​​for the wide-angle end state, the intermediate focal length state, and the telephoto end state, respectively. The number in parentheses after "Closest" is the distance on the optical axis from the close object to the lens surface closest to the object. The "m" in "(0.88m)" is the unit of distance in meters.

[0145] In the basic lens data, the surface numbers of aspheric surfaces are marked with an *, and the value of the paraxial radius of curvature is given in the column for the radius of curvature of the aspheric surface. In Table 3, the Sn row shows the surface numbers of the aspheric surfaces, and the KA and Am rows show the numerical values ​​of the aspheric coefficients for each aspheric surface. Note that m in Am is an integer of 3 or more, and differs depending on the surface. For example, for the 6th surface in Example 1, m = 4, 6, 8, 10, 12, 14, 16, 18, and 20. The numerical values ​​of the aspheric coefficients in Table 3, "E±n" (n: integer), are expressed as "×10 ±n " KA and Am are aspheric coefficients in the aspheric equation expressed below. Zd = C × h 2 / {1+(1-KA×C 2 ×h 2 ) 1 / 2}+ΣAm×h m however, Zd: Aspheric depth (the length of the perpendicular line drawn from a point on the aspheric surface at height h to a plane perpendicular to the optical axis Z where the apex of the aspheric surface is in contact) h: Height (distance from optical axis Z to lens surface) C: Reciprocal of paraxial curvature radius KA, Am: Aspheric coefficients In the aspheric surface formula, Σ means the summation with respect to m.

[0146] In the data in each table, the angle unit is degrees and the length unit is millimeters, but since the optical system can be used with proportional enlargement or reduction, other appropriate units can be used. Also, in each table shown below, values ​​are rounded to a predetermined number of decimal places.

[0147] [Table 1]

[0148] [Table 2]

[0149] [Table 3]

[0150] FIG. 6 shows each aberration diagram of the zoom lens of Example 1 in a state where the lens is focused on an object at infinity. In FIG. 6, from the left, spherical aberration, astigmatism, distortion, and lateral chromatic aberration are shown. In FIG. 6, the upper row labeled "Wide" shows the aberration in the wide-angle end state, the middle row labeled "Middle" shows the aberration in the intermediate focal length state, and the lower row labeled "Tele" shows the aberration in the telephoto end state. In the spherical aberration diagram, the aberrations at the d-line, C-line, and F-line are shown by solid lines, long dashed lines, and short dashed lines, respectively. In the astigmatism diagram, the aberration at the d-line in the sagittal direction is shown by solid lines, and the aberration at the d-line in the tangential direction is shown by short dashed lines. In the distortion diagram, the aberration at the d-line is shown by solid lines. In the lateral chromatic aberration diagram, the aberrations at the C-line and F-line are shown by long dashed lines and short dashed 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 =.

[0151] The symbols, meanings, description methods, and illustration methods of each piece of data related to the above-mentioned Example 1 are basically the same in the following Examples unless otherwise specified, so duplicated explanations will be omitted below.

[0152] [Example 1-1] Example 1-1 is an example in which an EX group EX is inserted into the zoom lens of Example 1. The configuration of the zoom lens of Example 1-1 and a cross-sectional view of a light beam are shown in FIG. 5. The zoom lens of Example 1-1 has a final lens group GEE in which an EX group EX is inserted inside the final lens group GE of Example 1, instead of the final lens group GE of Example 1. The configurations of the other lens groups and groups of Example 1-1 are the same as those of the zoom lens of Example 1.

[0153] For the zoom lens of Example 1-1, basic lens data is shown in Tables 4A and 4B, specifications and variable surface spacing in Table 5, aspheric coefficients in Table 6, and various aberration diagrams in Fig. 7. Here, the basic lens data is shown in two tables to avoid making one table too long, and the following tables will also be shown in two tables as appropriate.

[0154] [Table 4A]

[0155] [Table 4B]

[0156] [Table 5]

[0157] [Table 6]

[0158] [Example 2] The configuration and movement locus of the zoom lens of Example 2 are shown in Figure 8. The zoom lens of Example 2 is composed of, in order from the object side to the image side, a first lens group G1 having positive refractive power, a negative lens group UN having negative refractive power as a whole, an N lens group GN having negative refractive power, a P lens group GP having positive refractive power, and a final lens group GE having positive refractive power. The negative lens group UN is composed of one lens group.

[0159] When changing magnification from the wide-angle end to the telephoto end, the first lens group G1 and the final lens group GE are fixed with respect to the image plane Sim, and the negative lens group UN, the N lens group GN, and the P lens group GP move along the optical axis Z while changing the spacing between adjacent lens groups.

[0160] The first lens group G1 is composed of, in order from the object side to the image side, a 1a subgroup G1a, a 1b subgroup G1b, and a 1c subgroup G1c. When focusing from an object at infinity to a closest object, the 1a subgroup G1a is fixed with respect to the image plane Sim, and the 1b subgroup G1b and the 1c subgroup G1c move toward the object side while changing the mutual distance between them.

[0161] Regarding the zoom lens of Example 2, basic lens data is shown in Table 7, specifications and variable surface spacing in Table 8, aspheric coefficients in Table 9, and each aberration diagram is shown in FIG.

[0162] [Table 7]

[0163] [Table 8]

[0164] [Table 9]

[0165] [Example 3] The configuration and movement locus of the zoom lens of Example 3 are shown in Figure 10. The zoom lens of Example 3 is composed of, in order from the object side to the image side, a first lens group G1 having positive refractive power, a negative group UN having negative refractive power as a whole, an N lens group GN having negative refractive power, a P lens group GP having positive refractive power, and a final lens group GE having positive refractive power. The negative group UN is composed of two lens groups, in order from the object side to the image side, a second lens group G2 having positive refractive power, and a third lens group G3 having negative refractive power.

[0166] When changing magnification from the wide-angle end to the telephoto end, the first lens group G1 and the final lens group GE are fixed with respect to the image plane Sim, and the second lens group G2, the third lens group G3, the N lens group GN, and the P lens group GP move along the optical axis Z while changing the spacing between adjacent lens groups.

[0167] The first lens group G1 is composed of, in order from the object side to the image side, a 1a subgroup G1a, a 1b subgroup G1b, and a 1c subgroup G1c. When focusing from an object at infinity to a closest object, the 1a subgroup G1a is fixed with respect to the image plane Sim, and the 1b subgroup G1b and the 1c subgroup G1c move toward the object side while changing the mutual distance between them.

[0168] Regarding the zoom lens of Example 3, basic lens data is shown in Table 10, specifications and variable surface spacing in Table 11, aspheric coefficients in Table 12, and each aberration diagram is shown in FIG.

[0169] [Table 10]

[0170] [Table 11]

[0171] [Table 12]

[0172] [Example 4] The configuration and movement locus of the zoom lens of Example 4 are shown in Figure 12. The zoom lens of Example 4 is composed of, in order from the object side to the image side, a first lens group G1 having positive refractive power, a negative group UN having negative refractive power as a whole, an N lens group GN having negative refractive power, a P lens group GP having positive refractive power, and a final lens group GE having positive refractive power. The negative group UN is composed of two lens groups, in order from the object side to the image side, a second lens group G2 having positive refractive power, and a third lens group G3 having negative refractive power.

[0173] When changing magnification from the wide-angle end to the telephoto end, the first lens group G1 and the final lens group GE are fixed with respect to the image plane Sim, and the second lens group G2, the third lens group G3, the N lens group GN, and the P lens group GP move along the optical axis Z while changing the spacing between adjacent lens groups.

[0174] The first lens group G1 is composed of, in order from the object side to the image side, a 1a subgroup G1a, a 1b subgroup G1b, and a 1c subgroup G1c. When focusing from an object at infinity to a closest object, the 1a subgroup G1a is fixed with respect to the image plane Sim, and the 1b subgroup G1b and the 1c subgroup G1c move toward the object side while changing the mutual distance between them.

[0175] Regarding the zoom lens of Example 4, basic lens data is shown in Table 13, specifications and variable surface spacing are shown in Table 14, aspheric coefficients are shown in Table 15, and each aberration diagram is shown in FIG.

[0176] [Table 13]

[0177] [Table 14]

[0178] [Table 15]

[0179] [Example 5] The configuration and movement locus of the zoom lens of Example 5 are shown in Figure 14. The zoom lens of Example 5 is composed of, in order from the object side to the image side, a first lens group G1 having positive refractive power, a negative lens group UN having negative refractive power as a whole, an N lens group GN having negative refractive power, a P lens group GP having positive refractive power, and a final lens group GE having positive refractive power. The negative lens group UN is composed of one lens group.

[0180] When changing magnification from the wide-angle end to the telephoto end, the first lens group G1 and the final lens group GE are fixed with respect to the image plane Sim, and the negative lens group UN, the N lens group GN, and the P lens group GP move along the optical axis Z while changing the spacing between adjacent lens groups.

[0181] The first lens group G1 is composed of, in order from the object side to the image side, a 1a subgroup G1a, a 1b subgroup G1b, and a 1c subgroup G1c. When focusing from an object at infinity to a closest object, the 1a subgroup G1a is fixed with respect to the image plane Sim, and the 1b subgroup G1b and the 1c subgroup G1c move toward the object side while changing the mutual distance between them.

[0182] Regarding the zoom lens of Example 5, basic lens data is shown in Table 16, specifications and variable surface spacing in Table 17, aspheric coefficients in Table 18, and each aberration diagram is shown in FIG.

[0183] [Table 16]

[0184] [Table 17]

[0185] [Table 18]

[0186] [Example 6] The configuration and movement locus of the zoom lens of Example 6 are shown in Figure 16. The zoom lens of Example 6 is composed of, in order from the object side to the image side, a first lens group G1 having positive refractive power, a negative lens group UN having negative refractive power as a whole, an N lens group GN having negative refractive power, a P lens group GP having positive refractive power, and a final lens group GE having positive refractive power. The negative lens group UN is composed of one lens group.

[0187] When changing magnification from the wide-angle end to the telephoto end, the first lens group G1 and the final lens group GE are fixed with respect to the image plane Sim, and the negative lens group UN, the N lens group GN, and the P lens group GP move along the optical axis Z while changing the spacing between adjacent lens groups.

[0188] The first lens group G1 is composed of, in order from the object side to the image side, a 1a subgroup G1a, a 1b subgroup G1b, and a 1c subgroup G1c. When focusing from an object at infinity to a closest object, the 1a subgroup G1a is fixed with respect to the image plane Sim, and the 1b subgroup G1b and the 1c subgroup G1c move toward the object side while changing the mutual distance between them.

[0189] Regarding the zoom lens of Example 6, basic lens data is shown in Table 19, specifications and variable surface spacing in Table 20, aspheric coefficients in Table 21, and each aberration diagram is shown in FIG.

[0190] [Table 19]

[0191] [Table 20]

[0192] [Table 21]

[0193] [Example 7] The configuration and movement locus of the zoom lens of Example 7 are shown in Figure 18. The zoom lens of Example 7 is composed of, in order from the object side to the image side, a first lens group G1 having positive refractive power, a negative lens group UN having negative refractive power as a whole, an N lens group GN having negative refractive power, a P lens group GP having positive refractive power, and a final lens group GE having positive refractive power. The negative lens group UN is composed of one lens group.

[0194] When changing magnification from the wide-angle end to the telephoto end, the first lens group G1 and the final lens group GE are fixed with respect to the image plane Sim, and the negative lens group UN, the N lens group GN, and the P lens group GP move along the optical axis Z while changing the spacing between adjacent lens groups.

[0195] The first lens group G1 is composed of, in order from the object side to the image side, a 1a subgroup G1a, a 1b subgroup G1b, and a 1c subgroup G1c. When focusing from an object at infinity to a closest object, the 1a subgroup G1a is fixed with respect to the image plane Sim, and the 1b subgroup G1b and the 1c subgroup G1c move toward the object side while changing the mutual distance between them.

[0196] Regarding the zoom lens of Example 7, basic lens data is shown in Table 22, specifications and variable surface spacing in Table 23, aspheric coefficients in Table 24, and each aberration diagram is shown in FIG.

[0197] [Table 22]

[0198] [Table 23]

[0199] [Table 24]

[0200] [Example 8] The configuration and movement locus of the zoom lens of Example 8 are shown in Figure 20. The zoom lens of Example 8 is composed of, in order from the object side to the image side, a first lens group G1 having positive refractive power, a negative lens group UN having negative refractive power as a whole, an N lens group GN having negative refractive power, a P lens group GP having positive refractive power, and a final lens group GE having positive refractive power. The negative lens group UN is composed of one lens group.

[0201] When changing magnification from the wide-angle end to the telephoto end, the first lens group G1 and the final lens group GE are fixed with respect to the image plane Sim, and the negative lens group UN, the N lens group GN, and the P lens group GP move along the optical axis Z while changing the spacing between adjacent lens groups.

[0202] The first lens group G1 is composed of, in order from the object side to the image side, a 1a subgroup G1a, a 1b subgroup G1b, and a 1c subgroup G1c. When focusing from an object at infinity to a closest object, the 1a subgroup G1a is fixed with respect to the image plane Sim, and the 1b subgroup G1b and the 1c subgroup G1c move toward the object side while changing the mutual distance between them.

[0203] Regarding the zoom lens of Example 8, basic lens data is shown in Table 25, specifications and variable surface spacing in Table 26, aspheric coefficients in Table 27, and each aberration diagram is shown in FIG.

[0204] [Table 25]

[0205] [Table 26]

[0206] [Table 27]

[0207] [Example 9] The configuration and movement locus of the zoom lens of Example 9 are shown in Figure 22. The zoom lens of Example 9 is composed of, in order from the object side to the image side, a first lens group G1 having positive refractive power, a negative lens group UN having negative refractive power as a whole, an N lens group GN having negative refractive power, a P lens group GP having positive refractive power, and a final lens group GE having positive refractive power. The negative lens group UN is composed of one lens group.

[0208] When changing magnification from the wide-angle end to the telephoto end, the first lens group G1 and the final lens group GE are fixed with respect to the image plane Sim, and the negative lens group UN, the N lens group GN, and the P lens group GP move along the optical axis Z while changing the spacing between adjacent lens groups.

[0209] The first lens group G1 is composed of, in order from the object side to the image side, a 1a subgroup G1a, a 1b subgroup G1b, and a 1c subgroup G1c. When focusing from an object at infinity to a closest object, the 1a subgroup G1a is fixed with respect to the image plane Sim, and the 1b subgroup G1b and the 1c subgroup G1c move toward the object side while changing the mutual distance between them.

[0210] Regarding the zoom lens of Example 9, basic lens data is shown in Table 28, specifications and variable surface spacing in Table 29, aspheric coefficients in Table 30, and each aberration diagram is shown in FIG.

[0211] [Table 28]

[0212] [Table 29]

[0213] [Table 30]

[0214] [Example 10] The configuration and movement locus of the zoom lens of Example 10 are shown in Figure 24. The zoom lens of Example 10 is composed of, in order from the object side to the image side, a first lens group G1 having positive refractive power, a negative lens group UN having negative refractive power as a whole, an N lens group GN having negative refractive power, a P lens group GP having positive refractive power, and a final lens group GE having positive refractive power. The negative lens group UN is composed of one lens group.

[0215] When changing magnification from the wide-angle end to the telephoto end, the first lens group G1 and the final lens group GE are fixed with respect to the image plane Sim, and the negative lens group UN, the N lens group GN, and the P lens group GP move along the optical axis Z while changing the spacing between adjacent lens groups.

[0216] The first lens group G1 is composed of, in order from the object side to the image side, a 1a subgroup G1a, a 1b subgroup G1b, and a 1c subgroup G1c. When focusing from an object at infinity to a closest object, the 1a subgroup G1a is fixed with respect to the image plane Sim, and the 1b subgroup G1b and the 1c subgroup G1c move toward the object side while changing the mutual distance between them.

[0217] Regarding the zoom lens of Example 10, basic lens data is shown in Table 31, specifications and variable surface spacing in Table 32, aspheric coefficients in Table 33, and each aberration diagram is shown in FIG.

[0218] [Table 31]

[0219] [Table 32]

[0220] [Table 33]

[0221] [Example 11] The configuration and movement locus of the zoom lens of Example 11 are shown in Figure 26. The zoom lens of Example 11 is composed of, in order from the object side to the image side, a first lens group G1 having positive refractive power, a negative group UN having negative refractive power as a whole, an N lens group GN having negative refractive power, a P lens group GP having positive refractive power, and a final lens group GE having positive refractive power. The negative group UN is composed of two lens groups, in order from the object side to the image side, a second lens group G2 having negative refractive power, and a third lens group G3 having negative refractive power.

[0222] When changing magnification from the wide-angle end to the telephoto end, the first lens group G1 and the final lens group GE are fixed with respect to the image plane Sim, and the second lens group G2, the third lens group G3, the N lens group GN, and the P lens group GP move along the optical axis Z while changing the spacing between adjacent lens groups.

[0223] The first lens group G1 is composed of, in order from the object side to the image side, a 1a subgroup G1a, a 1b subgroup G1b, and a 1c subgroup G1c. When focusing from an object at infinity to a closest object, the 1a subgroup G1a is fixed with respect to the image plane Sim, and the 1b subgroup G1b and the 1c subgroup G1c move toward the object side while changing the mutual distance between them.

[0224] Regarding the zoom lens of Example 11, basic lens data is shown in Table 34, specifications and variable surface spacing in Table 35, aspheric coefficients in Table 36, and each aberration diagram is shown in FIG.

[0225] [Table 34]

[0226] [Table 35]

[0227] [Table 36]

[0228] [Example 12] The configuration and movement locus of the zoom lens of Example 12 are shown in Figure 28. The zoom lens of Example 12 is composed of, in order from the object side to the image side, a first lens group G1 having positive refractive power, a negative group UN having negative refractive power as a whole, an N lens group GN having negative refractive power, a P lens group GP having positive refractive power, and a final lens group GE having positive refractive power. The negative group UN is composed of two lens groups, in order from the object side to the image side, a second lens group G2 having negative refractive power, and a third lens group G3 having positive refractive power.

[0229] When changing magnification from the wide-angle end to the telephoto end, the first lens group G1 and the final lens group GE are fixed with respect to the image plane Sim, and the second lens group G2, the third lens group G3, the N lens group GN, and the P lens group GP move along the optical axis Z while changing the spacing between adjacent lens groups.

[0230] The first lens group G1 is composed of, in order from the object side to the image side, a 1a subgroup G1a, a 1b subgroup G1b, and a 1c subgroup G1c. When focusing from an object at infinity to a closest object, the 1a subgroup G1a is fixed with respect to the image plane Sim, and the 1b subgroup G1b and the 1c subgroup G1c move toward the object side while changing the mutual distance between them.

[0231] Regarding the zoom lens of Example 12, basic lens data is shown in Table 37, the specifications and variable surface spacing are shown in Table 38, the aspheric coefficients are shown in Table 39, and each aberration diagram is shown in FIG.

[0232] [Table 37]

[0233] [Table 38]

[0234] [Table 39]

[0235] [Example 13] The configuration and movement locus of the zoom lens of Example 13 are shown in Figure 30. The zoom lens of Example 13 is composed of, in order from the object side to the image side, a first lens group G1 having positive refractive power, a negative group UN having negative refractive power as a whole, an N lens group GN having negative refractive power, a P lens group GP having positive refractive power, and a final lens group GE having positive refractive power. The negative group UN is composed of one lens group. The zoom lens of Example 13 has a secondary aperture Stb in addition to an aperture stop St.

[0236] When changing magnification from the wide-angle end to the telephoto end, the first lens group G1 and the final lens group GE are fixed with respect to the image plane Sim, and the negative lens group UN, the N lens group GN, and the P lens group GP move along the optical axis Z while changing the spacing between adjacent lens groups.

[0237] The first lens group G1 is composed of, in order from the object side to the image side, a 1a subgroup G1a, a 1b subgroup G1b, and a 1c subgroup G1c. When focusing from an object at infinity to a closest object, the 1a subgroup G1a is fixed with respect to the image plane Sim, and the 1b subgroup G1b and the 1c subgroup G1c move toward the object side while changing the mutual distance between them.

[0238] Concerning the zoom lens of Example 13, basic lens data is shown in Table 40, specifications and variable surface spacing in Table 41, aspheric coefficients in Table 42, and each aberration diagram is shown in FIG.

[0239] [Table 40]

[0240] [Table 41]

[0241] [Table 42]

[0242] [Example 13-1] Example 13-1 is an example in which an EX group EX is inserted into the zoom lens of Example 13. A cross-sectional view of the configuration and light beam of the zoom lens of Example 13-1 is shown in FIG. 32. The method of illustrating the cross-sectional views of the following examples in which an EX group EX is inserted, including this example, is the same as that of FIG. 5. The zoom lens of Example 13-1 has a final lens group GEE in which an EX group EX is inserted inside the final lens group GE of Example 13, instead of the final lens group GE of Example 13. The configurations of the other lens groups and groups of Example 13-1 are the same as those of the zoom lens of Example 13.

[0243] For the zoom lens of Example 13-1, basic lens data is shown in Tables 43A and 43B, specifications and variable surface spacing is shown in Table 44, aspheric coefficients are shown in Table 45, and each aberration diagram is shown in FIG.

[0244] [Table 43A]

[0245] [Table 43B]

[0246] [Table 44]

[0247] [Table 45]

[0248] [Example 14] The configuration and movement locus of the zoom lens of Example 14 are shown in Figure 34. The zoom lens of Example 14 is composed of, in order from the object side to the image side, a first lens group G1 having positive refractive power, a negative lens group UN having negative refractive power as a whole, an N lens group GN having negative refractive power, a P lens group GP having positive refractive power, and a final lens group GE having positive refractive power. The negative lens group UN is composed of one lens group.

[0249] When changing magnification from the wide-angle end to the telephoto end, the first lens group G1 and the final lens group GE are fixed with respect to the image plane Sim, and the negative lens group UN, the N lens group GN, and the P lens group GP move along the optical axis Z while changing the spacing between adjacent lens groups.

[0250] The first lens group G1 is composed of, in order from the object side to the image side, a 1a subgroup G1a, a 1b subgroup G1b, and a 1c subgroup G1c. When focusing from an object at infinity to a closest object, the 1a subgroup G1a is fixed with respect to the image surface Sim, the 1b subgroup G1b moves toward the image side, and the 1c subgroup G1c moves toward the object side.

[0251] Regarding the zoom lens of Example 14, basic lens data is shown in Table 46, specifications and variable surface spacing are shown in Table 47, aspheric coefficients are shown in Tables 48A and 48B, and each aberration diagram is shown in FIG.

[0252] [Table 46]

[0253] [Table 47]

[0254] [Table 48A]

[0255] [Table 48B]

[0256] [Example 14-1] Example 14-1 is an example in which an EX group EX is inserted into the zoom lens of Example 14. A cross-sectional view of the configuration and light beam of the zoom lens of Example 14-1 is shown in FIG. 36. The zoom lens of Example 14-1 has a final lens group GEE in which an EX group EX is inserted inside the final lens group GE of Example 14, instead of the final lens group GE of Example 14. The configurations of the other lens groups and groups of Example 14-1 are the same as those of the zoom lens of Example 14.

[0257] For the zoom lens of Example 14-1, basic lens data is shown in Tables 49A and 49B, specifications and variable surface spacing is shown in Table 50, aspheric coefficients are shown in Tables 51A and 51B, and each aberration diagram is shown in FIG.

[0258] [Table 49A]

[0259] [Table 49B]

[0260] [Table 50]

[0261] [Table 51A]

[0262] [Table 51B]

[0263] [Example 15] The configuration and movement locus of the zoom lens of Example 15 are shown in Figure 38. The zoom lens of Example 15 is composed of, in order from the object side to the image side, a first lens group G1 having positive refractive power, a negative lens group UN having negative refractive power as a whole, an N lens group GN having negative refractive power, a P lens group GP having positive refractive power, and a final lens group GE having positive refractive power. The negative lens group UN is composed of one lens group.

[0264] When changing magnification from the wide-angle end to the telephoto end, the first lens group G1 and the final lens group GE are fixed with respect to the image plane Sim, and the negative lens group UN, the N lens group GN, and the P lens group GP move along the optical axis Z while changing the spacing between adjacent lens groups.

[0265] The first lens group G1 is composed of, in order from the object side to the image side, a 1a subgroup G1a, a 1b subgroup G1b, and a 1c subgroup G1c. When focusing from an object at infinity to a closest object, the 1a subgroup G1a is fixed with respect to the image plane Sim, and the 1b subgroup G1b and the 1c subgroup G1c move toward the object side while changing the mutual distance between them.

[0266] Concerning the zoom lens of Example 15, basic lens data is shown in Table 52, the specifications and variable surface spacing are shown in Table 53, the aspheric coefficients are shown in Table 54, and each aberration diagram is shown in FIG.

[0267] [Table 52]

[0268] [Table 53]

[0269] [Table 54]

[0270] [Example 15-1] Example 15-1 is an example in which an EX group EX is inserted into the zoom lens of Example 15. A cross-sectional view of the configuration and light beam of the zoom lens of Example 15-1 is shown in FIG. 40. The zoom lens of Example 15-1 has a final lens group GEE in which an EX group EX is inserted inside the final lens group GE of Example 15, instead of the final lens group GE of Example 15. The configurations of the other lens groups and groups of Example 15-1 are the same as those of the zoom lens of Example 15.

[0271] Regarding the zoom lens of Example 15-1, basic lens data is shown in Tables 55A and 55B, specifications and variable surface spacing is shown in Table 56, aspheric coefficients are shown in Table 57, and each aberration diagram is shown in FIG.

[0272] [Table 55A]

[0273] [Table 55B]

[0274] [Table 56]

[0275] [Table 57]

[0276] [Example 16] The configuration and movement locus of the zoom lens of Example 16 are shown in Figure 42. The zoom lens of Example 16 is composed of, in order from the object side to the image side, a first lens group G1 having positive refractive power, a negative lens group UN having negative refractive power as a whole, an N lens group GN having negative refractive power, a P lens group GP having positive refractive power, and a final lens group GE having positive refractive power. The negative lens group UN is composed of one lens group.

[0277] When changing magnification from the wide-angle end to the telephoto end, the first lens group G1 and the final lens group GE are fixed with respect to the image plane Sim, and the negative lens group UN, the N lens group GN, and the P lens group GP move along the optical axis Z while changing the spacing between adjacent lens groups.

[0278] The first lens group G1 is composed of, in order from the object side to the image side, a 1a subgroup G1a, a 1b subgroup G1b, and a 1c subgroup G1c. When focusing from an object at infinity to a closest object, the 1a subgroup G1a is fixed with respect to the image plane Sim, and the 1b subgroup G1b and the 1c subgroup G1c move toward the object side while changing the mutual distance between them.

[0279] Concerning the zoom lens of Example 16, basic lens data is shown in Table 58, the specifications and variable surface spacing are shown in Table 59, the aspheric coefficients are shown in Table 60, and each aberration diagram is shown in FIG.

[0280] [Table 58]

[0281] [Table 59]

[0282] [Table 60]

[0283] [Example 16-1] Example 16-1 is an example in which an EX group EX is inserted into the zoom lens of Example 16. A cross-sectional view of the configuration and light beam of the zoom lens of Example 16-1 is shown in FIG. 44. The zoom lens of Example 16-1 has a final lens group GEE in which an EX group EX is inserted inside the final lens group GE of Example 16, instead of the final lens group GE of Example 16. The configurations of the other lens groups and groups of Example 16-1 are the same as those of the zoom lens of Example 16.

[0284] Regarding the zoom lens of Example 16-1, basic lens data is shown in Tables 61A and 61B, specifications and variable surface spacing is shown in Table 62, aspheric coefficients are shown in Table 63, and each aberration diagram is shown in FIG.

[0285] [Table 61A]

[0286] [Table 61B]

[0287] [Table 62]

[0288] [Table 63]

[0289] [Example 17] The configuration and movement locus of the zoom lens of Example 17 are shown in Figure 46. The zoom lens of Example 17 is composed of, in order from the object side to the image side, a first lens group G1 having positive refractive power, a negative lens group UN having negative refractive power as a whole, an N lens group GN having negative refractive power, a P lens group GP having positive refractive power, and a final lens group GE having positive refractive power. The negative lens group UN is composed of one lens group.

[0290] When changing magnification from the wide-angle end to the telephoto end, the first lens group G1 and the final lens group GE are fixed with respect to the image plane Sim, and the negative lens group UN, the N lens group GN, and the P lens group GP move along the optical axis Z while changing the spacing between adjacent lens groups.

[0291] The first lens group G1 is composed of, in order from the object side to the image side, a 1a subgroup G1a, a 1b subgroup G1b, and a 1c subgroup G1c. When focusing from an object at infinity to a closest object, the 1a subgroup G1a is fixed with respect to the image surface Sim, the 1b subgroup G1b moves toward the image side, and the 1c subgroup G1c moves toward the object side.

[0292] Regarding the zoom lens of Example 17, basic lens data is shown in Table 64, specifications and variable surface spacing are shown in Table 65, aspheric coefficients are shown in Tables 66A and 66B, and each aberration diagram is shown in FIG.

[0293] [Table 64]

[0294] [Table 65]

[0295] [Table 66A]

[0296] [Table 66B]

[0297] [Example 18] The configuration and movement locus of the zoom lens of Example 18 are shown in Figure 48. The zoom lens of Example 18 is composed of, in order from the object side to the image side, a first lens group G1 having positive refractive power, a negative lens group UN having negative refractive power as a whole, an N lens group GN having negative refractive power, a P lens group GP having positive refractive power, and a final lens group GE having positive refractive power. The negative lens group UN is composed of one lens group.

[0298] When changing magnification from the wide-angle end to the telephoto end, the first lens group G1 and the final lens group GE are fixed with respect to the image plane Sim, and the negative lens group UN, the N lens group GN, and the P lens group GP move along the optical axis Z while changing the spacing between adjacent lens groups.

[0299] The first lens group G1 is composed of, in order from the object side to the image side, a 1a subgroup G1a, a 1b subgroup G1b, a 1c subgroup G1c, and a 1d subgroup G1d. When focusing from an object at infinity to a closest object, the 1a subgroup G1a is fixed with respect to the image surface Sim, the 1b subgroup G1b and the 1c subgroup G1c move toward the image side while changing the mutual interval, and the 1d subgroup G1d moves toward the object side.

[0300] Regarding the zoom lens of Example 18, basic lens data is shown in Table 67, specifications and variable surface spacing in Table 68, aspheric coefficients in Table 69, and each aberration diagram is shown in FIG.

[0301] [Table 67]

[0302] [Table 68]

[0303] [Table 69]

[0304] [Example 19] The configuration and movement locus of the zoom lens of Example 19 are shown in Figure 50. The zoom lens of Example 19 is composed of, in order from the object side to the image side, a first lens group G1 having positive refractive power, a negative lens group UN having negative refractive power as a whole, an N lens group GN having negative refractive power, a P lens group GP having positive refractive power, and a final lens group GE having positive refractive power. The negative lens group UN is composed of one lens group.

[0305] When changing magnification from the wide-angle end to the telephoto end, the first lens group G1 and the final lens group GE are fixed with respect to the image plane Sim, and the negative lens group UN, the N lens group GN, and the P lens group GP move along the optical axis Z while changing the spacing between adjacent lens groups.

[0306] The first lens group G1 is composed of, in order from the object side to the image side, a 1a subgroup G1a, a 1b subgroup G1b, a 1c subgroup G1c, and a 1d subgroup G1d. When focusing from an object at infinity to a closest object, the 1a subgroup G1a and the 1c subgroup G1c are fixed with respect to the image surface Sim, the 1b subgroup G1b moves toward the image side, and the 1d subgroup G1d moves toward the object side.

[0307] Regarding the zoom lens of Example 19, basic lens data is shown in Tables 70A and 70B, specifications and variable surface spacing is shown in Table 71, aspheric coefficients are shown in Table 72, and each aberration diagram is shown in FIG.

[0308] [Table 70A]

[0309] [Table 70B]

[0310] [Table 71]

[0311] [Table 72]

[0312] [Example 19-1] Example 19-1 is an example in which an EX group EX is inserted into the zoom lens of Example 19. A cross-sectional view of the configuration and light beam of the zoom lens of Example 19-1 is shown in FIG. 52. The zoom lens of Example 19-1 has a final lens group GEE in which an EX group EX is inserted inside the final lens group GE of Example 19, instead of the final lens group GE of Example 19. The configurations of the other lens groups and groups of Example 19-1 are the same as those of the zoom lens of Example 19.

[0313] Regarding the zoom lens of Example 19-1, basic lens data is shown in Tables 73A and 73B, specifications and variable surface spacing is shown in Table 74, aspheric coefficients are shown in Table 75, and each aberration diagram is shown in FIG.

[0314] [Table 73A]

[0315] [Table 73B]

[0316] [Table 74]

[0317] [Table 75]

[0318] Tables 76 to 79 show values ​​corresponding to conditional formulas (1) to (23) of the zoom lenses of Examples 1 to 19. Table 80 shows values ​​corresponding to conditional formulas (24) to (27) of the zoom lenses of Examples 1-1, 13-1 to 16-1, and 19-1. The values ​​corresponding to conditional formulas (1) to (23) are values ​​in a state where the EX group EX is not inserted, and the values ​​corresponding to conditional formulas (24) to (27) are values ​​in a state where the EX group EX is inserted. The values ​​corresponding to the examples shown in Tables 76 to 80 may be used as upper or lower limits for the conditional formulas to set preferred ranges for the conditional formulas.

[0319] [Table 76]

[0320] [Table 77]

[0321] [Table 78]

[0322] [Table 79]

[0323] [Table 80]

[0324] The zoom lenses of Examples 1 to 19 are compact, but have a large image circle and a maximum image height of 14.5 or more when focused on an object at infinity at the wide-angle end. The zoom lenses of Examples 1 to 19 are also wide-angle, with a maximum half angle of view of 30 degrees or more when focused on an object at infinity at the wide-angle end, and various aberrations are well corrected to maintain high optical performance.

[0325] Next, an imaging device according to an embodiment of the present disclosure will be described. Fig. 54 shows a schematic configuration diagram of an imaging device 100 according to an embodiment of the present disclosure. The imaging device 100 is configured to include a zoom lens 1 according to an embodiment of the present disclosure. Examples of the imaging device 100 include a cinema camera, a broadcast camera, a surveillance camera, a digital camera, and a video camera.

[0326] The imaging device 100 includes a zoom lens 1, a filter 2 arranged on the image side of the zoom lens 1, and an image sensor 3 arranged on the image side of the filter 2. The zoom lens 1 in Fig. 54 is shown conceptually. The zoom lens 1 includes an EX group EX that is inserted into or removed from the optical path to change the focal length of the zoom lens while keeping the imaging position constant.

[0327] The image sensor 3 converts an optical image formed by the zoom lens 1 into an electrical signal, and may be, for example, a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS). The image sensor 3 is disposed so that its imaging surface coincides with the image surface of the zoom lens 1. Although only one image sensor 3 is shown in FIG. 54, the imaging device 100 may be a so-called three-plate type imaging device that includes three image sensors.

[0328] The imaging device 100 also includes a signal processing unit 4, a magnification control unit 5, and a focus control unit 6. The signal processing unit 4 performs arithmetic processing on the output signal from the imaging element 3. The magnification control unit 5 controls the magnification of the zoom lens 1. The focus control unit 6 controls the focusing of the zoom lens 1.

[0329] Although the technology of the present disclosure has been described above with reference to the embodiments and examples, the technology of the present disclosure is not limited to the above embodiments and examples, and various modifications are possible. For example, the radius of curvature, surface spacing, refractive index, Abbe number, aspheric coefficient, etc. of each lens are not limited to the values ​​shown in the above examples, and may take other values.

[0330] Regarding the above-mentioned embodiments and examples, the following supplementary notes are further disclosed. [Appendix 1] A zoom lens, a first lens group having positive refractive power and disposed closest to the object; a negative group that is arranged adjacent to the image side of the first lens group, that is composed of two or less lens groups, and that has negative refractive power as a whole; an N lens group having negative refractive power, which is disposed closer to the image side than the negative group; a P lens group having positive refractive power, which is disposed closer to the image side than the negative lens group; a final lens group disposed closest to the image side, When changing magnification, the spacing between all adjacent lens groups changes, The focal length of the N lens group is fN. If the focal length of the first lens group is f1, then -6 <fN / f1<-0.55 (1) A zoom lens that satisfies conditional expression (1) expressed by: [Appendix 2] 2. The zoom lens according to claim 1, wherein the first lens group is fixed with respect to an image plane during zooming. [Appendix 3] 3. The zoom lens according to claim 1, wherein the final lens group is fixed with respect to an image plane during zooming. [Appendix 4] the P lens group is disposed adjacent to the image side of the N lens group, 4. The zoom lens according to claim 1, wherein the final lens group is disposed adjacent to the image side of the P lens group. [Appendix 5] 5. The zoom lens according to claim 1, wherein a part of the first lens group moves along the optical axis during focusing. [Appendix 6] the first lens group includes, in succession from the most object side to the image side, at least a 1a sub group, a 1b sub group, and a 1c sub group; The zoom lens according to claim 5, wherein, during focusing, a distance between the 1a sub group and the 1b sub group changes, and a distance between the 1b sub group and the 1c sub group changes. [Appendix 7] the first lens group includes, in order from the object side to the image side, a 1a sub-group, a 1b sub-group, and a 1c sub-group, The zoom lens according to claim 5, wherein, during focusing, the 1a sub-group is fixed with respect to an image plane, and the 1b sub-group and the 1c sub-group move along different trajectories. [Appendix 8] 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, If the focal length of the zoom lens when focused on an object at infinity at the wide-angle end is fw, 1.2 <Denw / fw<8 (2) 8. The zoom lens according to claim 1, which satisfies conditional expression (2) represented by: [Appendix 9] The focal length of the negative group is fUN, If the focal length of the N lens group is fN, 0.118 <fUN / fN<0.25 (3) 9. The zoom lens according to claim 1, which satisfies conditional expression (3) represented by: [Appendix 10] 10. The zoom lens according to claim 1, wherein, during zooming from a wide-angle end to a telephoto end, the N lens group moves along a locus that is convex toward the object side. [Appendix 11] the lens closest to the object side of the zoom lens is a negative lens; 11. The zoom lens according to claim 1, wherein the second lens from the object side of the zoom lens is a positive lens. [Appendix 12] 12. The zoom lens according to claim 1, wherein the first lens group includes one negative lens and four or more positive lenses. [Appendix 13] 13. The zoom lens according to claim 1, wherein the first lens group includes, in succession from the most object side to the image side, a negative lens, a positive lens, and a positive lens. [Appendix 14] When the lens is focused on an object at infinity at the wide-angle end, the longest air space on the optical axis between the lens surface of the P lens group closest to the object and the lens surface of the final lens group closest to the image is defined as the longest air space. 14. The zoom lens according to claim 1, wherein an EX group is removably arranged so that the EX group is inserted into the optical path with the longest air gap to change the focal length of the zoom lens while keeping the imaging position constant. [Appendix 15] 15. The zoom lens according to claim 14, wherein the maximum image height changes by inserting or extracting the EX group. [Appendix 16] the first lens group includes, in succession from the most object side to the image side, at least a 1a sub group and a 1b sub group; During focusing, the distance between the 1a sub-group and the 1b sub-group changes, If the focal length of the 1a subgroup is f1a, -0.85 <f1 / f1a<0.15 (4) The zoom lens according to claim 5, which satisfies conditional expression (4) expressed by: [Appendix 17] If the focal length of the negative group is fUN, then -0.4 <fUN / f1<-0.09 (5) 17. The zoom lens according to claim 1, which satisfies conditional expression (5) represented by: [Appendix 18] When the lens surface of the first lens group closest to the object side in a state where an object at infinity is focused at the wide-angle end is the distance on the optical axis to the paraxial entrance pupil position, Denw is used as the distance, 0.4 <Denw / f1<1.6 (6) 18. The zoom lens according to claim 1, which satisfies conditional expression (6) represented by: [Appendix 19] 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, If the maximum image height when focused on an object at infinity at the wide-angle end is IHw, 3.4 <Denw / IHw<7.5 (7) 19. The zoom lens according to claim 1, which satisfies conditional expression (7) represented by: [Appendix 20] The displacement amount of the N lens group in the optical axis direction during magnification change from the wide-angle end to the telephoto end is MovN, The focal length of the zoom lens when focused on an object at infinity at the telephoto end is ft, fw is the focal length of the zoom lens when focused on an object at infinity at the wide-angle end, If the sign of the displacement amount is negative when the N lens group moves toward the object side and positive when the N lens group moves toward the image side, -0.4 <MovN / (f1 / log(ft / fw))<0.1 (8) 19. The zoom lens according to claim 1, which satisfies conditional expression (8) represented by: [Appendix 21] The back focus in air equivalent distance when focusing on an object at infinity at the wide-angle end is Bfw, If the maximum image height when focused on an object at infinity at the wide-angle end is IHw, 1.9 <Bfw / IHw<6 (9) 21. The zoom lens according to claim 1, which satisfies conditional expression (9) represented by: [Appendix 22] The zoom lens according to claim 6 or 7, wherein the 1a sub group includes an aspheric lens having at least one surface whose absolute value of the radius of curvature at the position of the maximum effective diameter is larger than the absolute value of the paraxial radius of curvature. [Appendix 23] The zoom lens according to claim 6 or 7, wherein the 1c sub-group includes an aspheric lens having at least one surface whose absolute value of a radius of curvature at the position of the maximum effective diameter is larger than the absolute value of a paraxial radius of curvature. [Appendix 24] The zoom lens according to any one of Supplementary Note 1 to Supplementary Note 23, wherein the negative group includes an aspheric lens having at least one surface whose absolute value of a radius of curvature at the position of the maximum effective diameter is smaller than the absolute value of a paraxial radius of curvature. [Appendix 25] 25. The zoom lens according to claim 1, wherein the P lens group includes an aspheric lens having at least one surface whose absolute value of a radius of curvature at the position of the maximum effective diameter is larger than the absolute value of a paraxial radius of curvature. [Appendix 26] When the lens is focused on an object at infinity at the wide-angle end, the longest air space on the optical axis between the lens surface of the P lens group closest to the object and the lens surface of the final lens group closest to the image is defined as the longest air space. PF is the Petzval sum from the lens surface of the first lens group closest to the object side to the surface forming the longest air gap on the object side, If the maximum image height when focused on an object at infinity at the wide-angle end is IHw, 0.12 <PF×IHw<0.25 (10) 26. The zoom lens according to claim 1, which satisfies conditional expression (10) represented by: [Appendix 27] An imaging device comprising the zoom lens according to any one of claims 1 to 26. [Explanation of symbols]

[0331] 1 Zoom lens 2. Filters 3. Image sensor 4. Signal Processing Section 5 Magnification control section 6 Focus control section 100 Imaging device D1a Thickness D1b Thickness DAmax Maximum Air Distance Denw Distance DEX Thickness Dexw Distance DG1 Thickness ED Effective Diameter EX EX group G1 First lens group G1a 1a subgroup G1b 1b subgroup G1c 1st subgroup G1d 1d subgroup G2 2nd lens group G3 3rd lens group GE final lens group GEE final lens group GN N lens group GP P lens group IHEw maximum image height IHw maximum image height Lx Lens MovN Displacement MovP Displacement PP Optical Components Px position Sim image plane St Aperture Stb Secondary drawing tL1 Center thickness tN1 Center thickness UN negative group Xa On-axis luminous flux Xb Off-axis luminous flux Xb1 ray Z optical axis ωEt Maximum half angle of view ωEw Maximum half angle of view ωt Maximum half angle of view ωw Maximum half angle of view

Claims

1. A zoom lens, a first lens group having a positive refractive power and disposed closest to the object; a negative lens group arranged adjacent to the image side of the first lens group, the negative lens group being composed of two or less lens groups and having negative refractive power as a whole; an N lens group having negative refractive power, which is disposed closer to the image side than the negative group; a P lens group having positive refractive power, which is disposed closer to the image side than the negative lens group; a final lens group disposed closest to the image side, When changing magnification, the spacing between all adjacent lens groups changes, The focal length of the N lens group is fN. If the focal length of the first lens group is f1, -6<fN / f1<-0.55 (1) A zoom lens that satisfies the conditional expression (1) expressed by:

2. 2. The zoom lens according to claim 1, wherein the first lens group is fixed relative to an image plane during zooming.

3. 2. The zoom lens according to claim 1, wherein the final lens group is fixed relative to an image plane during zooming.

4. the P lens group is disposed adjacent to the image side of the N lens group, 2. The zoom lens according to claim 1, wherein the final lens group is disposed adjacent to the image side of the P lens group.

5. 2. The zoom lens according to claim 1, wherein a portion of the first lens group moves along the optical axis during focusing.

6. the first lens group includes at least a 1a sub group, a 1b sub group, and a 1c sub group, which are successively arranged in order from the most object side to the image side; 6. The zoom lens according to claim 5, wherein, during focusing, a distance between the 1a-subgroup and the 1b-subgroup changes, and a distance between the 1b-subgroup and the 1c-subgroup changes.

7. the first lens group includes, in order from the object side to the image side, a 1a sub group, a 1b sub group, and a 1c sub group, 6. The zoom lens according to claim 5, wherein, during focusing, the 1a-subgroup is fixed with respect to an image plane, and the 1b-subgroup and the 1c-subgroup move along different trajectories.

8. 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, When the focal length of the zoom lens at the wide-angle end is set to fw and the zoom lens is focused on an object at infinity, 1.2<Denw / fw<8 (2) 2. The zoom lens according to claim 1, which satisfies conditional expression (2) expressed as follows:

9. The focal length of the negative group is fUN, If the focal length of the N lens group is fN, 0.118<fUN / fN<0.25 (3) 2. The zoom lens according to claim 1, which satisfies conditional expression (3) expressed as follows:

10. 2. The zoom lens according to claim 1, wherein, during zooming from the wide-angle end to the telephoto end, the N lens group moves along a locus that is convex toward the object side.

11. the lens closest to the object side of the zoom lens is a negative lens; 2. The zoom lens according to claim 1, wherein the second lens from the object side of the zoom lens is a positive lens.

12. 2. The zoom lens according to claim 1, wherein the first lens group includes one negative lens and four or more positive lenses.

13. 2. The zoom lens according to claim 1, wherein the first lens group includes, in succession from the most object side to the image side, a negative lens, a positive lens, and a positive lens.

14. When the focus is on an object at infinity at the wide-angle end, the longest air space on the optical axis between the lens surface of the P lens group closest to the object and the lens surface of the final lens group closest to the image is defined as the maximum air space.

2. The zoom lens according to claim 1, wherein an EX group is removably arranged so that the EX group is inserted into the optical path with the longest air gap to change the focal length of the zoom lens while keeping the image position constant.

15. 15. The zoom lens according to claim 14, wherein the maximum image height is changed by inserting or extracting the EX group.

16. the first lens group includes, in succession from the most object side to the image side, at least a 1a sub group and a 1b sub group; During focusing, the distance between the 1a subgroup and the 1b subgroup changes, When the focal length of the 1a subgroup is f1a, -0.85<f1 / f1a<0.15 (4) 6. The zoom lens according to claim 5, which satisfies conditional expression (4) expressed as follows:

17. If the focal length of the negative group is fUN, then -0.4<fUN / f1<-0.09 (5) 2. The zoom lens according to claim 1, which satisfies conditional expression (5) expressed by:

18. 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, 0.4<Denw / f1<1.6 (6) 2. The zoom lens according to claim 1, which satisfies conditional expression (6) expressed as follows:

19. 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, If the maximum image height when focused on an object at infinity at the wide-angle end is IHw, 3.4<Denw / IHw<7.5 (7) 2. The zoom lens according to claim 1, which satisfies conditional expression (7) expressed as follows:

20. The displacement amount of the N lens group in the optical axis direction during magnification change from the wide-angle end to the telephoto end is MovN, The focal length of the zoom lens when focused on an object at infinity at the telephoto end is ft, fw is the focal length of the zoom lens when focused on an object at infinity at the wide-angle end, If the sign of the displacement amount is negative when the N lens group moves toward the object side and positive when the N lens group moves toward the image side, -0.4<MovN / (f1 / log(ft / fw))<0.1 (8) 2. The zoom lens according to claim 1, which satisfies conditional expression (8) expressed as follows:

21. The back focus in air equivalent distance when focused on an object at infinity at the wide-angle end is Bfw, If the maximum image height when focused on an object at infinity at the wide-angle end is IHw, 1.9<Bfw / IHw<6 (9) 2. The zoom lens according to claim 1, which satisfies conditional expression (9) expressed as follows:

22. 7. The zoom lens according to claim 6, wherein the 1a subgroup includes an aspheric lens having at least one surface whose absolute value of the radius of curvature at the position of the maximum effective diameter is larger than the absolute value of the paraxial radius of curvature.

23. 7. The zoom lens according to claim 6, wherein the 1c sub-group includes an aspheric lens having at least one surface whose absolute value of the radius of curvature at the position of the maximum effective diameter is larger than the absolute value of the paraxial radius of curvature.

24. 2. The zoom lens according to claim 1, wherein the negative group includes an aspheric lens having at least one surface whose absolute value of the radius of curvature at the position of the maximum effective diameter is smaller than the absolute value of the paraxial radius of curvature.

25. 2. The zoom lens according to claim 1, wherein the P lens group includes an aspheric lens having at least one surface whose absolute value of the radius of curvature at the position of the maximum effective diameter is larger than the absolute value of the paraxial radius of curvature.

26. When the focus is on an object at infinity at the wide-angle end, the longest air space on the optical axis between the lens surface of the P lens group closest to the object and the lens surface of the final lens group closest to the image is defined as the maximum air space. PF is the Petzval sum from the lens surface of the first lens group closest to the object side to the surface forming the longest air gap on the object side, If the maximum image height when focused on an object at infinity at the wide-angle end is IHw, 0.12<PF×IHw<0.25 (10) 2. The zoom lens according to claim 1, which satisfies conditional expression (10) expressed as follows:

27. An imaging device comprising the zoom lens according to any one of claims 1 to 26.

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