Variable power optical system and imaging apparatus

Abstract

The invention provides a variable magnification optical system which is compact and light in weight and maintains good optical performance in the whole variable magnification area, and an imaging device provided with the variable magnification optical system. The variable magnification optical system includes, in order from an object side to an image side, a first lens group having a negative refractive power, a second lens group having a positive refractive power, and a subsequent group including one or more lens groups. When changing magnification, the first lens group moves, and all intervals between adjacent lens groups change. One of the lens groups included in the subsequent group is a focusing lens group that moves along the optical axis at the time of focusing. The variable magnification optical system satisfies a preset conditional expression.

Description

Technical Field

[0001] The technology of the present invention relates to a variable magnification optical system and a camera device. Background Art

[0002] Conventionally, as variable power optical systems that can be used in imaging devices such as digital cameras, there are known variable power optical systems described in Patent Documents 1 and 2 listed below.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2021-162822

[0004] Patent Document 2: Japanese Patent Application Publication No. 2021-086024

[0005] There is a demand for a variable power optical system that is compact and lightweight and maintains good optical performance over the entire variable power range. These demands are increasing year by year. Summary of the invention

[0006] The present invention provides a variable magnification optical system which is compact and lightweight and maintains good optical performance in the entire variable magnification range, and an imaging device having the variable magnification optical system.

[0007] A first aspect of the present invention is a variable power optical system, which includes, from the object side to the image side, a first lens group having negative power, a second lens group having positive power, and a subsequent group including one or more lens groups, wherein when the power is changed, the first lens group moves and all intervals between adjacent lens groups change, and one of the lens groups included in the subsequent group is a focus lens group that moves along the optical axis when focusing, and the following conditional expressions (1), (2), (3), (4), and (5) are satisfied:

[0008] 4.5<TLw / (ft×tanωt)<8 (1);

[0009] 0.4<Bfw / (ft×tanωt)<3 (2);

[0010] 0.9<(fw×TLw) / ft 2 <3.2 (3);

[0011] 1.6<NG1L+0.01×v G1L<2.3 (4);

[0012] 0.1<Dsum / (TLw-Bfw)<0.8 (5).

[0013] The symbols of conditional expressions (1), (2), (3), (4) and (5) are defined as follows. The sum of the distance on the optical axis from the lens surface closest to the object side of the first lens group to the lens surface closest to the image side of the subsequent lens group in the state of focusing on an infinitely distant object at the wide-angle end and the back focal length of the entire system in terms of air conversion distance is set to TLw. The focal length of the entire system in the state of focusing on an infinitely distant object at the telephoto end is set to ft. The maximum half angle of view in the state of focusing on an infinitely distant object at the telephoto end is set to ωt. The back focal length of the entire system in the state of focusing on an infinitely distant object at the wide-angle end is set to Bfw. The focal length of the entire system in the state of focusing on an infinitely distant object at the wide-angle end is set to fw. The refractive index of any lens included in the first lens group with respect to the d-line and the Abbe number based on the d-line are set to NG1L and v G1L, respectively. The sum of the thicknesses on the optical axis of all lens groups is set to Dsum.

[0014] In the second aspect of the present invention, in the variable power optical system of the first aspect, the following conditional expression (1-1) is satisfied:

[0015] 5.4<TLw / (ft×tanωt)<7 (1-1).

[0016] In the third aspect of the present invention, in the variable power optical system of the first aspect, the following conditional expression (2-1) is satisfied:

[0017] 0.55<Bfw / (ft×tanωt)<2 (2-1).

[0018] Regarding the fourth aspect of the present invention, in the variable power optical system of the first aspect, when the thickness of the first lens group on the optical axis is set to dG1 and the focal length of the first lens group is set to f1, the following conditional expression (6) is satisfied:

[0019] 0.4<dG1 / |f1|<2 (6).

[0020] In the fifth aspect of the present invention, in the variable power optical system of the fourth aspect, the following conditional expression (6-1) is satisfied:

[0021] 0.55<dG1 / |f1|<1.65 (6-1).

[0022] Regarding the 6th mode of the present invention, in the zoom optical system of the 1st mode, the 1st lens group includes an L1nm lens as a negative meniscus lens with a convex surface facing the unjoined object side, an L1n lens as a negative lens with a concave surface facing the unjoined image side, and an L1p lens as a positive lens, the L1n lens is arranged at a position adjacent to the image side of the L1nm lens, and the L1p lens is arranged at a position closer to the image side than the L1n lens.

[0023] In a seventh aspect of the present invention, in the variable power optical system of the sixth aspect, a negative lens is included, and when the refractive index of the negative lens arranged between the L1nm lens and the L1p lens with respect to the d-line and the Abbe number of the d-line reference are NG1n and vG1n, respectively, the negative lens satisfies the following conditional expression (7):

[0024] 1.7<NG1n+0.01×v G1n<2.16 (7),

[0025] The negative lens satisfying conditional expression (7) is the L1n lens or a negative lens arranged adjacent to the image side of the L1n lens.

[0026] Regarding the eighth aspect of the present invention, in the variable power optical system of the seventh aspect, the negative lens satisfying the conditional expression (7) satisfies the following conditional expression (7-1):

[0027] 1.74<NG1n+0.01×v G1n<2.14 (7-1).

[0028] Regarding the ninth aspect of the present invention, in the variable power optical system of the sixth aspect, when the distance on the optical axis between the L1nm lens and the L1n lens is set to dm, and the thickness on the optical axis of the first lens group is set to dG1, the following conditional expression (8) is satisfied:

[0029] 0.01<dm / dG1<0.9 (8).

[0030] According to a tenth aspect of the present invention, in the variable power optical system of the sixth aspect, the object-side surface of the L1n lens is an aspherical surface whose refractive power at the position of the maximum effective diameter is shifted more positively than the refractive power in the paraxial region.

[0031] According to an eleventh aspect of the present invention, in the variable power optical system of the tenth aspect, the object-side surface of the L1n lens is concave in the paraxial region and is convex in the peripheral portion including the position of the maximum effective diameter.

[0032] In the twelfth aspect of the present invention, in the variable power optical system of the first aspect, when the focal length of the second lens group is set to f2 and the focal length of the first lens group is set to f1, the following conditional expression (9) is satisfied:

[0033] 0.3<f2 / |f1|<5 (9).

[0034] In the 13th aspect of the present invention, in the variable power optical system of the 12th aspect, the following conditional expression (9-1) is satisfied:

[0035] 0.65<f2 / |f1|<3 (9-1).

[0036] In the fourteenth aspect of the present invention, in the variable power optical system of the thirteenth aspect, the following conditional expression (1-1) is satisfied:

[0037] 5.4<TL W / (ft×tanωt)<7 (1-1).

[0038] Regarding the 15th embodiment of the present invention, in the zoom optical system of the 14th embodiment, the first lens group includes an L1nm lens as a negative meniscus lens with its convex surface facing the unbonded object side, an L1n lens as a negative lens with its concave surface facing the unbonded image side, and an L1p lens as a positive lens, the L1n lens is arranged at a position adjacent to the image side of the L1nm lens, and the L1ρ lens is arranged at a position closer to the image side than the L1n lens.

[0039] Regarding the 16th aspect of the present invention, in the variable power optical system of the 15th aspect, a negative lens is included, and when the refractive index of the negative lens arranged between the L1nm lens and the L1p lens with respect to the d-line and the Abbe number of the d-line reference are NG1n and v G1n, respectively, the negative lens satisfies the following conditional expression (7-1):

[0040] 1.74<NG1n+0.01×v G1n<2.14 (7-1),

[0041] The negative lens satisfying conditional expression (7-1) is the L1n lens or a negative lens arranged adjacent to the image side of the L1n lens.

[0042] According to a seventeenth aspect of the present invention, in the variable power optical system of the sixteenth aspect, the first lens group includes a positive lens having a convex surface facing the object side, on the most object side.

[0043] In the eighteenth aspect of the present invention, in the variable power optical system of the sixteenth aspect, the following conditional expression (4-1) is satisfied:

[0044] 1.82<NG1L+0.01×v G1L<1.91 (4-1).

[0045] Regarding the 19th aspect of the present invention, in the variable power optical system of the 16th aspect, when the thickness of the first lens group on the optical axis is set to dG1, the following conditional expression (6-1) is satisfied:

[0046] 0.55<dG1 / |f1|<1.65 (6-1).

[0047] Regarding the 20th aspect of the present invention, in the variable power optical system of the 19th aspect, the following conditional expression (6-2) is satisfied:

[0048] 0.75<dG1 / |f1|<1.35 (6-2).

[0049] Regarding the 21st aspect of the present invention, in the variable power optical system of the 19th aspect, when the distance on the optical axis between the L1nm lens and the L1n lens is set to dm, the following conditional expression (8) is satisfied:

[0050] 0.01<dm / dG1<0.9 (8).

[0051] According to a 22nd aspect of the present invention, in the variable power optical system according to the 19th aspect, the first lens group includes four or less lenses.

[0052] Regarding the 23rd aspect of the present invention, in the variable power optical system of the 19th aspect, the object side surface of the L1n lens is an aspherical surface whose refractive power at the position of the maximum effective diameter is shifted in a positive direction compared with the refractive power in the paraxial region.

[0053] Regarding the 24th aspect of the present invention, in the variable power optical system of the 1st aspect, when the focal length of the first lens group is set to f1, the following conditional expression (10) is satisfied:

[0054] 0.45<fw / |f1|<2 (10).

[0055] Regarding the 25th aspect of the present invention, in the variable power optical system of the first aspect, the first lens group includes an L1nm lens which is a negative meniscus lens with a convex surface facing the unjoined object side, and when the paraxial curvature radius of the object side surface of the L1nm lens is set to Rf and the paraxial curvature radius of the image side surface of the L1nm lens is set to Rr, the following conditional expression (11) is satisfied:

[0056] 1<(Rf+Rr) / (Rf-Rr)<7 (11).

[0057] Regarding the 26th aspect of the present invention, in the variable power optical system of the first aspect, an anti-vibration group is arranged at a position closer to the image side than the first lens group, and moves in a direction intersecting the optical axis during image shake correction. When the focal length of the anti-vibration group is set to fois, the following conditional expression (12) is satisfied:

[0058] 0.3<ft / |fois|<4 (12).

[0059] Regarding the 27th aspect of the present invention, in the variable power optical system of the first aspect, when the focal length of the focus lens group is set to ffoc, the following conditional expression (13) is satisfied:

[0060] 0.3<ft / |ffoc|<3 (13).

[0061] Regarding the 28th aspect of the present invention, in the variable power optical system of the first aspect, an Lr lens is arranged at a position closer to the image side than the focus lens group, and when the refractive index of the Lr lens with respect to the d-line and the Abbe number of the d-line reference are respectively set to Nr and vr, the following conditional expression (14) is satisfied:

[0062] 1.7<Nr+0.01×vr<2.16 (14).

[0063] A 29th aspect of the present invention is an imaging device including the variable power optical system according to any one of the 1st to 28th aspects.

[0064] In addition, the words "including..." and "including..." in this specification mean that in addition to the listed components, it may also include lenses that essentially have no optical focal length, optical elements other than lenses such as apertures, filters and cover glasses, and mechanical parts such as lens flanges, lens barrels, camera elements and hand-shake correction mechanisms.

[0065] In this specification, "a group of lenses having positive optical power" means that the entire group has positive optical power. Similarly, "a group of lenses having negative optical power" means that the entire group has negative optical power. "A lens having positive optical power" has the same meaning as a "positive lens". "A lens having negative optical power" has the same meaning as a "negative lens". The "group of lenses" in this specification is not limited to a structure including multiple lenses, but may also be a structure including only one lens.

[0066] The "entire system" in this specification refers to the variable magnification optical system. The "focal length" used in the conditional expression is the paraxial focal length. Unless otherwise specified, the "distance on the optical axis" used in the conditional expression is the geometric distance. Unless otherwise specified, the value used in the conditional expression is the value when the d-line is used as a reference in the state of focusing on an object at infinity. Unless otherwise specified, the curvature radius, the sign of the optical focal length, and the surface shape related to the lens including the aspheric surface use the paraxial area. Regarding the sign of the paraxial curvature radius, the sign of the paraxial curvature radius of the surface of the convex shape facing the object side is set to positive, and the sign of the paraxial curvature radius of the surface of the convex shape facing the image side is set to negative.

[0067] Effects of the Invention

[0068] According to the present invention, it is possible to provide a variable power optical system which is compact and lightweight and which maintains good optical performance over the entire variable power range, and an imaging device including the variable power optical system. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] Figure 1 It is a cross-sectional view and a diagram showing a movement trajectory of a variable power optical system corresponding to the variable power optical system of Example 1 and according to an embodiment.

[0070] Figure 2 yes Figure 1 The present invention is a cross-sectional view of the structure of the variable power optical system and is a diagram for explaining symbols of conditional expressions.

[0071] Figure 3 It is a diagram for explaining the position of the maximum effective diameter.

[0072] Figure 4 1 and 2 are diagrams showing various aberrations of the variable power optical system of Example 1.

[0073] Figure 5 It is a cross-sectional view showing the structure of the variable power optical system of Example 2 and a diagram showing a movement trajectory.

[0074] Figure 6 These are various aberration diagrams of the variable power optical system of Example 2.

[0075] Figure 7 It is a cross-sectional view showing the structure of the variable power optical system of Example 3 and a diagram showing the movement trajectory.

[0076] Figure 8 1 and 10 are diagrams showing various aberrations of the variable power optical system of Example 3.

[0077] Fig. 9 It is a cross-sectional view showing the structure of the variable power optical system of Example 4 and a diagram of the movement trajectory.

[0078] Fig.10 These are various aberration diagrams of the variable power optical system of Example 4.

[0079] Fig.11 It is a cross-sectional view showing the structure of the variable power optical system of Example 5 and a diagram of the movement trajectory.

[0080] Fig.12 These are various aberration diagrams of the variable power optical system of Example 5.

[0081] Fig.13 It is a cross-sectional view showing the structure of the variable power optical system of Example 6 and a diagram of the movement trajectory.

[0082] Fig.14 These are various aberration diagrams of the variable power optical system of Example 6.

[0083] Fig.15 It is a cross-sectional view showing the structure of the variable power optical system of Example 7 and a diagram of the movement trajectory.

[0084] Fig.16 These are various aberration diagrams of the variable power optical system of Example 7.

[0085] Fig.17 It is a cross-sectional view showing the structure of the variable power optical system of Example 8 and a diagram of the movement trajectory.

[0086] Fig.18 These are various aberration diagrams of the variable power optical system of Example 8.

[0087] Fig.19 It is a cross-sectional view showing the structure of the variable power optical system of Example 9 and a diagram of the movement trajectory.

[0088] Fig. 20 These are various aberration diagrams of the variable power optical system of Example 9.

[0089] Fig.21 It is a cross-sectional view showing the structure of the variable power optical system of Example 10 and a diagram of the movement trajectory.

[0090] Fig. 22 These are various aberration diagrams of the variable power optical system of Example 10.

[0091] Fig.23 It is a cross-sectional view showing the structure of the variable power optical system of Example 11 and a diagram of the movement trajectory.

[0092] Fig.24 These are various aberration diagrams of the variable power optical system of Example 11.

[0093] Fig.25 It is a cross-sectional view showing the structure of the variable power optical system of Example 12 and a diagram of the movement trajectory.

[0094] Fig.26 These are various aberration diagrams of the variable power optical system of Example 12.

[0095] Fig. 27 It is a cross-sectional view showing the structure of the variable power optical system of Example 13 and a diagram of the movement trajectory.

[0096] Fig.28 These are various aberration diagrams of the variable power optical system of Example 13.

[0097] Fig.29 It is a cross-sectional view showing the structure of the variable power optical system of Example 14 and a diagram of the movement trajectory.

[0098] Fig.30 These are various aberration diagrams of the variable power optical system of Example 14.

[0099] Fig.31 It is a cross-sectional view showing the structure of the variable power optical system of Example 15 and a diagram of the movement trajectory.

[0100] Fig.32 These are various aberration diagrams of the variable power optical system of Example 15.

[0101] Fig.33It is a cross-sectional view showing the structure of the variable power optical system of Example 16 and a diagram of the movement trajectory.

[0102] Fig.34 These are various aberration diagrams of the variable power optical system of Example 16.

[0103] Fig.35 It is a cross-sectional view showing the structure of the variable power optical system of Example 17 and a diagram of the movement trajectory.

[0104] Fig.36 These are various aberration diagrams of the variable power optical system of Example 17.

[0105] Fig.37 It is a cross-sectional view showing the structure of the variable power optical system of Example 18 and a diagram of the movement trajectory.

[0106] Fig.38 These are various aberration diagrams of the variable power optical system of Example 18.

[0107] Fig.39 It is a cross-sectional view showing the structure of the variable power optical system of Example 19 and a diagram of the movement trajectory.

[0108] Fig.40 These are various aberration diagrams of the variable power optical system of Example 19.

[0109] Fig.41 It is a cross-sectional view showing the structure of the variable power optical system of Example 20 and a diagram of the movement trajectory.

[0110] Fig.42 These are various aberration diagrams of the variable power optical system of Example 20.

[0111] Fig.43 This is a perspective view of the front side of the imaging device according to one embodiment.

[0112] Fig.44 This is a perspective view of the back side of the imaging device according to one embodiment.

[0113] Explanation of symbols

[0114] 1-zoom optical system, 20-interchangeable lens, 30-camera, 31-camera body, 32-shutter button, 33-power button, 34-operating unit, 35-operating unit, 36-display unit, 37-mount, 38-imaging element, Bfw-back focal length, dG1-thickness, dL1n-center thickness, dL1nh-thickness, dL1nm-center thickness, dL1nmh-thickness, dm-distance, Dfoc-thickness, ED-effective diameter, G1-1st lens group, G2-2nd lens group, G3-3rd lens group, G4-4th lens group, G5-5th lens group, GR-subsequent groups, L11~L51-lens, Lx-lens, Px-position, Sim-image plane, St-aperture stop, TLw-total optical length, Xa-on-axis beam, Xb-off-axis beam, Xb1-light, Z-optical axis, ωt-maximum semi-angle of view, ωw-maximum semi-angle of view. DETAILED DESCRIPTION

[0115] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0116] exist Figure 1 2 shows the structure of the variable power optical system and the cross-sectional view and movement trajectory of the light beam involved in one embodiment of the present invention. Figure 1 In FIG. 1 , the upper section labeled “Wide” shows the wide-angle end state, and the lower section labeled “Tele” shows the telephoto end state. Figure 1 In FIG. 1 , as light beams, an axial light beam at a wide angle end and a light beam with a maximum half viewing angle ωw, and an axial light beam at a telephoto end and a light beam with a maximum half viewing angle ωt are shown. Figure 2 Shown in Figure 1 A cross-sectional view of the structure of the variable magnification optical system at the wide-angle end. Figure 1 and Figure 2 , showing the state of focusing on an object at infinity, with the left side being the object side and the right side being the image side. Figure 1 and Figure 2 The example shown corresponds to the variable magnification optical system of Example 1 described later. Figure 1 Explain and refer to Figure 2 .

[0117] The zoom optical system of the present invention includes a first lens group G1 having negative optical power, a second lens group G2 having positive optical power, and a subsequent group GR including one or more lens groups in sequence from the object side to the image side along the optical axis Z. When zooming, the first lens group G1 moves, and all intervals between adjacent lens groups change. The above structure is conducive to suppressing various aberrations in the entire zoom range.

[0118] In particular, by setting the first lens group G1 as a group with negative power, it is advantageous to obtain a wide viewing angle. By setting the first lens group G1 as a group with negative power and setting the second lens group G2 as a group with positive power, it is advantageous to suppress various aberrations. By setting the second lens group G2 as a group with positive power, it is possible to reduce the height of the light incident on the subsequent group GR from the optical axis Z, which is advantageous to suppress the aberration variation during zooming.

[0119] In addition, in this specification, a group whose interval with adjacent groups in the optical axis direction changes when the magnification is changed is set as one lens group. When the magnification is changed, the interval between adjacent lenses inside one lens group does not change. That is, the "lens group" is a component of the zoom optical system, and is a part that includes at least one lens separated by an air gap that changes when the magnification is changed. When the magnification is changed, each lens group unit moves or is fixed. The "lens group" may include components other than lenses that do not have optical focal power, such as aperture stop St, etc.

[0120] As an example, Figure 1 Each group of the variable power optical system shown is constructed as follows. The first lens group G1 includes four lenses, namely, lenses L11 to L14, in order from the object side to the image side. The second lens group G2 includes lens L21, aperture stop St, and lenses L22 to L23 in order from the object side to the image side. The subsequent group GR includes one lens group. The subsequent group GR includes the third lens group G3, and the third lens group G3 includes one lens, namely, lens L31. In addition, Figure 1 The aperture stop St shown does not indicate size or shape but indicates the position on the optical axis.

[0121] exist Figure 1 In the example of , when changing the magnification, the first lens group G1, the second lens group G2 and the third lens group G3 move along the optical axis Z by changing the intervals between adjacent lens groups. Figure 1 In FIG. 1 , between the upper and lower figures, solid arrows are used to indicate the approximate movement trajectory of each lens group when zooming from the wide-angle end to the telephoto end.

[0122] in addition, Figure 1 The example shown is just an example, and the variable power optical system of the present invention can be variously modified within the scope of the technical spirit of the present invention. The preferred structure and achievable structure of the variable power optical system of the present invention are described below.

[0123] The first lens group G1 may be configured to include a positive lens having a convex surface facing the object side at the most object side. This configuration is advantageous in correcting spherical aberration at the telephoto end.

[0124] The first lens group G1 may be configured to include four or less lenses. In this configuration, it is possible to suppress various aberrations while preventing the first lens group G1 from being enlarged.

[0125] The first lens group G1 preferably includes an L1nm lens as a negative meniscus lens with its convex surface facing the unbonded object side, an L1n lens as a negative lens with its concave surface facing the unbonded image side, and an L1p lens as a positive lens. Moreover, preferably, the L1n lens is arranged at a position adjacent to the image side of the L1nm lens, and the L1p lens is arranged at a position closer to the image side than the L1n lens. In addition, the L1p lens may also be arranged at a position adjacent to the image side of the L1n lens, and may not be arranged at a position adjacent to the image side of the L1n lens as long as it is located closer to the image side than the L1n lens. When the first lens group G1 includes the L1nm lens, L1n lens, and L1p lens of the above-mentioned preferred structure, it is beneficial to correct distortion and field curvature, especially at the wide-angle end. Figure 1 In the example of , lens L12 corresponds to L1nm lens, lens L13 corresponds to L1n lens, and lens L14 corresponds to L1p lens.

[0126] The object-side surface of the L1n lens may be configured as an aspherical surface whose refractive power at the position of the maximum effective diameter is shifted more positively than the refractive power in the paraxial region. This configuration is advantageous in correcting distortion.

[0127] Here, reference Figure 3 , the “position of the maximum effective diameter” in this specification is explained. Figure 3 This is a diagram for illustration purposes. Figure 3 In the figure, the left side is the object side and the right side is the image side. Figure 3 The on-axis beam Xa and the off-axis beam Xb passing through the lens Lx are shown in FIG. Figure 3 In the example, the light ray Xb1, which is the upper light ray of the off-axis light beam Xb, is the light ray passing through the outermost side. The "outer side" mentioned here refers to the radial outer side centered on the optical axis Z, that is, the side away from the optical axis Z. In this specification, the position of the intersection of the light ray passing through the outermost side and the lens surface is the position Px of the maximum effective diameter. And, twice the distance from the position Px of the maximum effective diameter to the optical axis Z becomes the effective diameter ED of the object side surface of the lens Lx. In addition, in Figure 3 In the example of FIG. 1 , the upper ray of the off-axis beam Xb is the ray that passes the outermost side. However, which ray becomes the ray that passes the outermost side varies depending on the optical system.

[0128] In addition, the phrase "the optical power at the position of the maximum effective diameter is shifted in a more positive direction than the optical power in the paraxial region" in this specification has the following meanings based on the sign of the optical power. When the surface has positive optical power at both the paraxial region and the position of the maximum effective diameter, it means that the surface has a stronger positive optical power at the position of the maximum effective diameter than the paraxial region. When the surface has negative optical power at both the paraxial region and the position of the maximum effective diameter, it means that the surface has a weaker negative optical power at the position of the maximum effective diameter than the paraxial region. When the surface has optical powers of different signs at the paraxial region and the position of the maximum effective diameter, it means that the surface has a negative optical power at the paraxial region and a positive optical power at the position of the maximum effective diameter.

[0129] The object-side surface of the L1n lens is concave in the paraxial region and convex in the peripheral portion including the position of the maximum effective diameter. This configuration is advantageous in correcting field curvature.

[0130] The L1nm lens or L1n lens can also be configured as a composite aspheric lens. When configured in this way, it is advantageous to suppress various aberrations. The composite aspheric lens has the advantages of being lower in cost than a molded aspheric lens made of only glass and higher in environmental resistance than an aspheric lens made of only resin.

[0131] In addition, in this specification, a composite aspheric lens refers to a lens (e.g., a spherical lens) and a film having an aspheric shape formed on the lens as a whole, and the whole functions as a single aspheric lens. For most composite aspheric lenses, the lens (e.g., a spherical lens) on which the film is formed is made of glass, and the film is made of resin. In this specification, a composite aspheric lens is not regarded as a cemented lens, but is used as a single lens that is not cemented.

[0132] When the first lens group G1 includes the above-mentioned L1n lens, as shown in Examples 6 and 7 described later, it is also possible to configure an L2nm lens as a negative meniscus lens with its convex surface facing the object side, which is arranged at a position closer to the image side than the L1n lens. When so configured, it is beneficial to correct image curvature. Then, the surface on the object side of the L2nm lens can also be configured as an aspheric surface whose optical power at the position of the maximum effective diameter is more negatively displaced than the optical power in the paraxial region. When so configured, it is beneficial to correct image curvature. The L2nm lens is preferably arranged in the first lens group G1. The L2nm lens can be arranged at a position adjacent to the image side of the L1n lens.

[0133] In this specification, “the optical power at the position of the maximum effective diameter is shifted more negatively than the optical power in the paraxial region” has the following meanings based on the sign of the optical power. When the surface has negative optical power at both the paraxial region and the position of the maximum effective diameter, it means that the surface has a stronger negative optical power at the position of the maximum effective diameter than the paraxial region. When the surface has positive optical power at both the paraxial region and the position of the maximum effective diameter, it means that the surface has a weaker positive optical power at the position of the maximum effective diameter than the paraxial region. When the surface has optical powers of different signs at the paraxial region and the position of the maximum effective diameter, it means that the surface has a positive optical power at the paraxial region and a negative optical power at the position of the maximum effective diameter.

[0134] The variable power optical system of the present invention preferably has a focusing function. For example, it can be configured so that one of the lens groups included in the subsequent group GR is a focus lens group that moves along the optical axis Z when focusing. Focusing is performed by moving the focus lens group. Figure 1 In the example of FIG. 1 , the focusing lens group includes the third lens group G3. Figure 1 The brackets and left-right arrows of the third lens group G3 in the lower figure indicate that the third lens group G3 is a focus lens group and the direction of movement when focusing from an object at infinity to the nearest object. In addition, the focus lens group functions in the entire zoom range including the wide-angle end state, but Figure 1 In order to avoid complicating the figure, the above arrows are only included in the lower figure.

[0135] The focus lens group may be configured to include one lens or one cemented lens. When configured in this way, the focus lens group can be easily miniaturized and lightened, which is advantageous for increasing the speed of focusing.

[0136] Furthermore, the variable magnification optical system of the present invention preferably has an image shake correction function. For example, it may be configured such that an anti-vibration group is arranged at a position closer to the image side than the first lens group G1, and moves in a direction intersecting the optical axis Z during image shake correction. Image shake correction is performed by moving the anti-vibration group. Figure 1 In the example, the anti-vibration group includes lens L21. Figure 1 The brackets and downward arrows around lens L21 in the lower figure indicate that lens L21 is an anti-vibration group. In addition, the anti-vibration group functions in the entire zoom range including the wide-angle end state, but Figure 1 In order to avoid complicating the figure, the above arrows are only included in the lower figure.

[0137] The anti-vibration group may also be constructed to include all the lenses included in the second lens group G2. By using the second lens group G2 with a lower light height as the anti-vibration group, it is advantageous to miniaturize and lighten the anti-vibration group. When the second lens group G2 includes both a positive lens and a negative lens, it is advantageous to suppress the variation of chromatic aberration during image shake correction. The anti-vibration group may also be constructed to include one lens closest to the object side in the second lens group G2. By including one lens in the anti-vibration group, it is further advantageous to miniaturize and lighten the anti-vibration group. By configuring the anti-vibration group at the position closest to the object side of the second lens group G2, it is easy to secure space for setting up the anti-vibration mechanism.

[0138] The number of lenses included in the variable power optical system of the present invention may be configured to be 8 or more and 12 or less. This configuration is advantageous for miniaturization and weight reduction of the entire optical system.

[0139] Next, the preferred structure and achievable structure related to the conditional formula of the variable power optical system of the present invention are described. In addition, in the description related to the following conditional formula, in order to avoid redundant description, the same symbols are used for the parts with the same definition, and the repeated description of the symbols is omitted. Furthermore, in order to avoid redundant description, the "variable power optical system of the present invention" is also referred to as the "variable power optical system" below.

[0140] The variable magnification optical system preferably satisfies the following conditional formula (1). The sum of the distance on the optical axis from the lens surface closest to the object side of the first lens group G1 to the lens surface closest to the image side of the subsequent lens group GR in the state of focusing on an infinitely distant object at the wide-angle end and the back focal length of the entire system in terms of air conversion distance is set to TLw. The focal length of the entire system in the state of focusing on an infinitely distant object at the telephoto end is set to ft. The maximum half angle of view in the state of focusing on an infinitely distant object at the telephoto end is set to ωt. Tan is a tangent. TLw is the total optical length in the state of focusing on an infinitely distant object at the wide-angle end. As an example, Figure 2 The above optical total length TLw is shown in FIG. By making the corresponding value of conditional expression (1) not less than the lower limit value, it is beneficial to suppress various aberrations in the entire zoom range. By making the corresponding value of conditional expression (1) not more than the upper limit value, it is beneficial to miniaturize the entire optical system.

[0141] 4.5<TLw / (ft×tanωt)<8 (1)

[0142] In order to obtain better characteristics, the lower limit value of conditional formula (1) is more preferably set to 5, more preferably 5.3, more preferably 5.4, more preferably 5.6, and more preferably 5.7. In order to obtain better characteristics, the upper limit value of conditional formula (1) is more preferably set to 7.5, more preferably 7.2, more preferably 7, more preferably 6.9, and more preferably 6.8. For example, the variable magnification optical system more preferably satisfies the following conditional formula (1-1).

[0143] 5.4<TLw / (ft×tanωt)<7 (1-1)

[0144] The variable power optical system preferably satisfies the following conditional expression (2). In which, the back focal length of the entire system in the state of focusing on an infinitely distant object at the wide angle end is set to Bfw in terms of air conversion distance. The back focal length in terms of air conversion distance is the air conversion distance on the optical axis from the lens surface closest to the image side of the variable power optical system to the image plane Sim. As an example, Figure 2 The back focal length Bfw is shown in FIG. By making the corresponding value of conditional expression (2) not less than the lower limit value, the back focal length Bfw will not become too short, so it is easy to install the bayonet replacement mechanism. By making the corresponding value of conditional expression (2) not more than the upper limit value, the back focal length Bfw will not become too long, so it is easy to achieve miniaturization.

[0145] 0.4<Bfw / (ft×tanωt)<3 (2)

[0146] In order to obtain better characteristics, the lower limit of conditional formula (2) is more preferably set to 0.45, more preferably 0.5, more preferably 0.55, and more preferably 0.6. In order to obtain better characteristics, the upper limit of conditional formula (2) is more preferably set to 2.5, more preferably 2.2, more preferably 2, and more preferably 1.8. For example, the variable magnification optical system more preferably satisfies the following conditional formula (2-1).

[0147] 0.55<Bfw / (ft×tanωt)<2 (2-1)

[0148] The zoom optical system preferably satisfies the following conditional expression (3). Here, the focal length of the entire system in the state of focusing on an infinitely distant object at the wide-angle end is set to fw. By making the corresponding value of conditional expression (3) not below the lower limit value, it is beneficial to suppress various aberrations in the entire zoom area. By making the corresponding value of conditional expression (3) not above the upper limit value, it is beneficial to miniaturize the entire optical system or to obtain a sufficient zoom ratio as a zoom optical system.

[0149] 0.9<(fw×TLw) / ft 2 <3.2 (3)

[0150] In order to obtain better characteristics, the lower limit of conditional formula (3) is more preferably set to 1, more preferably 1.1, more preferably 1.2, and more preferably 1.25. In order to obtain better characteristics, the upper limit of conditional formula (3) is more preferably set to 3, more preferably 2.8, more preferably 2.6, and more preferably 2.45.

[0151] The variable power optical system preferably satisfies the following conditional expression (4). Here, the refractive index of any lens included in the first lens group G1 with respect to the d-line and the Abbe number of the d-line reference are set to NG1L and v G1L, respectively. In addition, NG1L and v G1L of the conditional expression (4) are set to values ​​related to the same lens. By making the corresponding value of the conditional expression (4) not below the lower limit value, it is possible to select materials other than materials with low refractive index and low Abbe number, so that it is easy to correct the chromatic aberration of magnification at the wide-angle end. By making the corresponding value of the conditional expression (4) not above the upper limit value, it is possible to select materials other than materials with high refractive index and high Abbe number, so it is possible to select materials with low specific gravity and easy to reduce weight.

[0152] 1.6<NG1L+0.01×v G1L<2.3 (4)

[0153] In order to obtain better characteristics, the lower limit value of conditional formula (4) is more preferably set to 1.65, more preferably 1.7, more preferably 1.72, more preferably 1.74, more preferably 1.76, more preferably 1.78, more preferably 1.8, and more preferably 1.82. In order to obtain better characteristics, the upper limit value of conditional formula (4) is more preferably set to 2.2, more preferably 2.16, more preferably 2.15, more preferably 2.14, more preferably 2.13, more preferably 2.12, more preferably 2.11, and more preferably 1.91. For example, the variable magnification optical system more preferably satisfies the following conditional formula (4-1).

[0154] 1.82<NG1L+0.01×v G1L<1.91 (4-1)

[0155] The variable power optical system preferably satisfies the following conditional expression (5). Here, the sum of the thicknesses on the optical axis of all lens groups is set to Dsum. In other words, Dsum is the value obtained by adding the thicknesses on the optical axis of each lens group for all lens groups in the entire system. The "thickness on the optical axis of the lens group" in this specification refers to the distance on the optical axis from the surface of the lens group closest to the object side to the surface of the lens group closest to the image side. By making the corresponding value of conditional expression (5) not be less than the lower limit value, the thickness of each lens in the variable power optical system will not become too small, which is conducive to ensuring good optical performance. By making the corresponding value of conditional expression (5) not be more than the upper limit value, it is conducive to suppressing the increase in weight of the entire variable power optical system.

[0156] 0.1<Dsum / (TLw-Bfw)<0.8 (5)

[0157] In order to obtain better characteristics, the lower limit of conditional formula (5) is more preferably set to 0.2, more preferably 0.25, more preferably 0.28, more preferably 0.3, and more preferably 0.32. In order to obtain better characteristics, the upper limit of conditional formula (5) is more preferably set to 0.75, more preferably 0.7, more preferably 0.65, more preferably 0.6, and more preferably 0.55.

[0158] The variable power optical system preferably satisfies the following conditional expression (6). Here, the thickness of the first lens group G1 on the optical axis is dG1. The focal length of the first lens group G1 is f1. As an example, Figure 2 The thickness dG1 is shown in FIG. By making the corresponding value of conditional expression (6) not less than the lower limit value, it is advantageous to suppress various aberrations in the entire zoom range. By making the corresponding value of conditional expression (6) not more than the upper limit value, it is advantageous to reduce the weight of the first lens group G1.

[0159] 0.4<dG1 / |f1|<2 (6)

[0160] In order to obtain better characteristics, the lower limit value of conditional formula (6) is more preferably set to 0.5, more preferably 0.55, more preferably 0.65, more preferably 0.7, more preferably 0.75, and more preferably 0.8. In order to obtain better characteristics, the upper limit value of conditional formula (6) is more preferably set to 1.8, more preferably 1.65, more preferably 1.55, more preferably 1.45, more preferably 1.35, and more preferably 1.31. For example, the variable magnification optical system more preferably satisfies the following conditional formula (6-1), and more preferably satisfies the following conditional formula (6-2).

[0161] 0.55<dG1 / |f1|<1.65 (6-1)

[0162] 0.75<dG1 / |f1|<1.35 (6-2)

[0163] In a configuration in which the first lens group G1 includes the L1nm lens, the L1n lens, and the L1p lens, the L1n lens is arranged at a position adjacent to the image side of the L1nm lens, and the L1p lens is arranged at a position closer to the image side than the L1n lens, the variable power optical system preferably includes a negative lens satisfying the following conditional expression (7). In this case, the negative lens satisfying the conditional expression (7) is preferably the L1n lens or a negative lens arranged adjacent to the image side of the L1n lens. Here, the refractive index of the negative lens arranged between the L1nm lens and the L1p lens with respect to the d-line and the Abbe number of the d-line reference are NG1n and v G1n, respectively. By making the corresponding value of the conditional expression (7) not less than the lower limit value, it is possible to select a material other than a material with a low refractive index and a low Abbe number, so that it is easy to correct the chromatic aberration of magnification at the wide angle end. By making the corresponding value of the conditional expression (7) not more than the upper limit value, it is possible to select a material other than a material with a high refractive index and a high Abbe number, so that it is possible to select a material with a small specific gravity and easy to reduce weight.

[0164] 1.7<NG1n+0.01×v G1n<2.16 (7)

[0165] In order to obtain better characteristics, the lower limit of conditional formula (7) is more preferably set to 1.72, more preferably 1.74, more preferably 1.76, more preferably 1.78, and more preferably 1.8. In order to obtain better characteristics, the upper limit of conditional formula (7) is more preferably set to 2.15, more preferably 2.14, more preferably 2.13, more preferably 2.12, and more preferably 2.11. For example, the negative lens satisfying conditional formula (7) more preferably satisfies the following conditional formula (7-1).

[0166] 1.74<NGln+0.01×v G1n<2.14 (7-1)

[0167] In a configuration where the first lens group G1 includes the L1nm lens, the L1n lens, and the L1p lens, the L1n lens is disposed adjacent to the image side of the L1nm lens, and the L1p lens is disposed closer to the image side than the L1n lens, the variable power optical system preferably satisfies the following conditional expression (8). Here, the distance on the optical axis between the L1nm lens and the L1n lens is set to dm. As an example, Figure 2The distance dm is shown in FIG. By making the corresponding value of conditional expression (8) not less than the lower limit value, the intensity of stray light that is reflected on the surface of the object side of the L1n lens and then reflected on the surface of the image side of the L1nm lens and collected on the image plane Sim can be suppressed. By making the corresponding value of conditional expression (8) not more than the upper limit value, the enlargement of the diameter of the L1nm lens can be suppressed.

[0168] 0.01<dm / dG1<0.9 (8)

[0169] In order to obtain better characteristics, the lower limit of conditional formula (8) is more preferably set to 0.1, more preferably 0.15, more preferably 0.17, more preferably 0.19, and more preferably 0.2. In order to obtain better characteristics, the upper limit of conditional formula (8) is more preferably set to 0.8, more preferably 0.7, more preferably 0.65, more preferably 0.6, and more preferably 0.57.

[0170] The zoom optical system preferably satisfies the following conditional expression (9). Here, the focal length of the second lens group G2 is set to f2. By making the corresponding value of the conditional expression (9) not less than the lower limit value, the optical power of the first lens group G1 will not become too weak, and the optical power of the second lens group G2 will not become too strong, which is beneficial for correcting the spherical aberration on the telephoto side. By making the corresponding value of the conditional expression (9) not more than the upper limit value, the optical power of the first lens group G1 will not become too strong, and the optical power of the second lens group G2 will not become too weak, which is beneficial for correcting the spherical aberration on the wide-angle side. In addition, by making the corresponding value of the conditional expression (9) not more than the upper limit value, a high zoom ratio can be easily obtained without increasing the movement amount of the second lens group G2 with a zoom function, which is beneficial for miniaturization of the total optical length.

[0171] 0.3<f2 / |f1|<5 (9)

[0172] In order to obtain better characteristics, the lower limit value of conditional formula (9) is more preferably set to 0.65, more preferably 0.7, more preferably 0.75, and more preferably 0.8. In order to obtain better characteristics, the upper limit value of conditional formula (9) is more preferably set to 3, more preferably 2.8, more preferably 2.6, and more preferably 2.5. For example, the variable magnification optical system more preferably satisfies the following conditional formula (9-1).

[0173] 0.65<f2 / |f1|<3 (9-1)

[0174] The zoom optical system preferably satisfies the following conditional expression (10). By making the corresponding value of conditional expression (10) not less than the lower limit value, the optical power of the first lens group G1 will not become too weak, so that the movement amount of the first lens group G1 during zooming can be suppressed. By making the corresponding value of conditional expression (10) not more than the upper limit value, the optical power of the first lens group G1 will not become too strong, which is conducive to suppressing the aberration change during zooming.

[0175] 0.45<fw / |f1|<2 (10)

[0176] In order to obtain better characteristics, the lower limit of conditional formula (10) is more preferably set to 0.52, more preferably 0.58, more preferably 0.62, and more preferably 0.65. In order to obtain better characteristics, the upper limit of conditional formula (10) is more preferably set to 1.7, more preferably 1.5, more preferably 1.4, and more preferably 1.3.

[0177] In a structure in which the first lens group G1 includes the above-mentioned L1nm lens, the variable power optical system preferably satisfies the following conditional expression (11). Here, the paraxial curvature radius of the surface on the object side of the L1nm lens is set to Rf. The paraxial curvature radius of the surface on the image side of the L1nm lens is set to Rr. The conditional expression (11) specifies the so-called shape factor of the L1nm lens. By making the corresponding value of the conditional expression (11) not be less than the lower limit value, it is particularly easy to correct the astigmatism on the telephoto side. By making the corresponding value of the conditional expression (11) not be more than the upper limit value, it is easy to correct the spherical aberration on the telephoto side well.

[0178] 1<(Rf+Rr) / (Rf-Rr)<7 (11)

[0179] In order to obtain better characteristics, the lower limit of conditional formula (11) is more preferably set to 1.1, more preferably 1.15, more preferably 1.2, and more preferably 1.25. In order to obtain better characteristics, the upper limit of conditional formula (11) is more preferably set to 6, more preferably 5, more preferably 4.5, and more preferably 4.

[0180] In a structure in which an anti-vibration group that moves in a direction intersecting the optical axis Z during image shake correction is arranged at a position closer to the image side than the first lens group G1, the zoom optical system preferably satisfies the following conditional expression (12). Here, the focal length of the anti-vibration group is set to fois. By making the corresponding value of conditional expression (12) not be less than the lower limit value, the movement amount of the anti-vibration group during image shake correction can be suppressed, which is beneficial to the miniaturization of the entire zoom optical system and the miniaturization of the anti-vibration unit. By making the corresponding value of conditional expression (12) not be more than the upper limit value, the optical focal length of the anti-vibration group will not become too strong, which is beneficial to suppress the aberration change during image shake correction.

[0181] 0.3<ft / |fois|<4 (12)

[0182] In order to obtain better characteristics, the lower limit of conditional formula (12) is more preferably set to 0.5, more preferably 0.6, more preferably 0.65, and more preferably 0.7. In order to obtain better characteristics, the upper limit of conditional formula (12) is more preferably set to 3.5, more preferably 3, more preferably 2.5, and more preferably 2.

[0183] In a structure in which the zoom optical system includes a focus lens group, the zoom optical system preferably satisfies the following conditional expression (13). Here, the focal length of the focus lens group is set to ffoc. By making the corresponding value of conditional expression (13) not be less than the lower limit value, the optical power of the focus lens group will not become too weak, so that the movement of the focus lens group during focusing can be suppressed. By making the corresponding value of conditional expression (13) not be more than the upper limit value, the optical power of the focus lens group will not become too strong, which is conducive to suppressing the aberration change during focusing.

[0184] 0.3<ft / |ffoc|<3 (13)

[0185] In order to obtain better characteristics, the lower limit of conditional formula (13) is more preferably set to 0.4, more preferably 0.5, more preferably 0.55, and more preferably 0.6. In order to obtain better characteristics, the upper limit of conditional formula (13) is more preferably set to 2.5, more preferably 2.2, more preferably 1.9, and more preferably 1.8.

[0186] In a structure in which the zoom optical system includes a focus lens group and an Lr lens arranged at a position closer to the image side than the focus lens group, the zoom optical system preferably satisfies the following conditional formula (14). Here, the refractive index of the Lr lens relative to the d-line and the Abbe number of the d-line reference are set to Nr and vr, respectively. By making the corresponding value of the conditional formula (14) not be less than the lower limit value, it is possible to select materials other than materials with low refractive index and low Abbe number, so that it is easy to correct the chromatic aberration of magnification at the wide-angle end. By making the corresponding value of the conditional formula (14) not be more than the upper limit value, it is possible to select materials other than materials with high refractive index and high Abbe number, so it is possible to select materials with low specific gravity and easy to reduce weight.

[0187] 1.7<Nr+0.01×vr<2.16 (14)

[0188] In order to obtain better characteristics, the lower limit of conditional formula (14) is more preferably set to 1.72, more preferably 1.74, more preferably 1.76, more preferably 1.78, and more preferably 1.8. In order to obtain better characteristics, the upper limit of conditional formula (14) is more preferably set to 2.15, more preferably 2.14, more preferably 2.13, more preferably 2.12, and more preferably 2.11.

[0189] The zoom optical system preferably satisfies the following conditional expression (15). By making the corresponding value of conditional expression (15) not less than the lower limit value, the optical power of the first lens group G1 will not become too weak, so that the movement amount of the first lens group G1 during zooming can be suppressed. By making the corresponding value of conditional expression (15) not more than the upper limit value, the optical power of the first lens group G1 will not become too strong, which is conducive to suppressing the aberration change during zooming.

[0190] 1<ft / |f1|<3.5 (15)

[0191] In order to obtain better characteristics, the lower limit of conditional expression (15) is more preferably 1.1, more preferably 1.2, and more preferably 1.3. In order to obtain better characteristics, the upper limit of conditional expression (15) is more preferably 3, more preferably 2.8, and more preferably 2.5.

[0192] The zoom optical system preferably satisfies the following conditional expression (16). By making the corresponding value of conditional expression (16) not less than the lower limit value, the optical power of the first lens group G1 will not become too strong, which is conducive to suppressing the aberration change when zooming. By making the corresponding value of conditional expression (16) not more than the upper limit value, the optical power of the first lens group G1 will not become too weak, so the movement of the first lens group G1 when zooming can be suppressed, and it is conducive to suppressing the distortion aberration at the wide-angle end.

[0193] 0.4<|f1| / (fw×ft) 1 / 2 <2.2 (16)

[0194] In order to obtain better characteristics, the lower limit value of conditional expression (16) is more preferably set to 0.5, further preferably to 0.55, and further preferably to 0.6c. In order to obtain better characteristics, the upper limit value of conditional expression (16) is more preferably set to 1.8, further preferably to 1.5, and further preferably to 1.4.

[0195] The zoom optical system preferably satisfies the following conditional expression (17). By making the corresponding value of conditional expression (17) not be less than the lower limit value, the optical power of the second lens group G2 will not become too strong, so that the image curvature generated in the second lens group G2 can be reduced, and it is beneficial to correct aberrations when zooming. By making the corresponding value of conditional expression (17) not be more than the upper limit value, the optical power of the second lens group G2 will not become too weak, so the movement amount of the second lens group G2 when zooming can be suppressed, which is beneficial to shortening the total optical length.

[0196] 0.4<f2 / (fw×ft) 1 / 2 <3.5 (17)

[0197] In order to obtain better characteristics, the lower limit of conditional expression (17) is more preferably 0.6, more preferably 0.7, and more preferably 0.8. In order to obtain better characteristics, the upper limit of conditional expression (17) is more preferably 2.7, more preferably 2.2, and more preferably 1.8.

[0198] The variable power optical system preferably satisfies the following conditional expression (18). By making the corresponding value of the conditional expression (18) not less than the lower limit value, it is advantageous to ensure the strength of the first lens group G1. By making the corresponding value of the conditional expression (18) not more than the upper limit value, it is advantageous to reduce the weight of the first lens group G1.

[0199] 0.15<dG1 / (TLw-Bfw)<0.5 (18)

[0200] In order to obtain better characteristics, the lower limit of conditional expression (18) is more preferably set to 0.17, more preferably 0.18, and more preferably 0.19. In order to obtain better characteristics, the upper limit of conditional expression (18) is more preferably set to 0.4, more preferably 0.35, and more preferably 0.32.

[0201] The zoom optical system preferably satisfies the following conditional expression (19). Here, the open F value in the state of focusing on an infinitely distant object at the telephoto end is set to FNot. By making the corresponding value of conditional expression (19) not be less than the lower limit value, it is conducive to high performance. By making the corresponding value of conditional expression (19) not be more than the upper limit value, the optical power of the first lens group G1 will not become too weak, so the movement amount of the first lens group G1 during zooming can be suppressed, and it is conducive to suppressing the distortion aberration at the wide-angle end.

[0202] 1.5<|f1| / (ft / FNot)<8 (19)

[0203] In order to obtain better characteristics, the lower limit of conditional expression (19) is more preferably 2, more preferably 2.3, and more preferably 2.5. In order to obtain better characteristics, the upper limit of conditional expression (19) is more preferably 7, more preferably 6.5, and more preferably 6.

[0204] The variable power optical system preferably satisfies the following conditional expression (20). By making the corresponding value of conditional expression (20) not be less than the lower limit value, the focal length of the focus lens group will not become too weak, thereby suppressing the movement of the focus lens group during focusing. By making the corresponding value of conditional expression (20) not be more than the upper limit value, the focal length of the focus lens group will not become too strong, thereby helping to suppress the aberration change during focusing.

[0205] 0.1<fw / |ffoc|<2 (20)

[0206] In order to obtain better characteristics, the lower limit of conditional expression (20) is more preferably 0.16, more preferably 0.18, and more preferably 0.2. In order to obtain better characteristics, the upper limit of conditional expression (20) is more preferably 1.5, more preferably 1.2, and more preferably 1.

[0207] In the structure in which the first lens group G1 includes the above-mentioned L1nm lens, the variable magnification optical system preferably satisfies the following conditional expression (21). Here, the refractive index of the L1nm lens with respect to the d-line is set to N1nm. By making the corresponding value of the conditional expression (21) not less than the lower limit value, the L1nm lens is easy to have a sufficient negative focal length, which is conducive to good correction of distortion aberration. By making the corresponding value of the conditional expression (21) not more than the upper limit value, it is easy to form the L1nm lens without using a material with a large dispersion, which is conducive to good correction of magnification chromatic aberration.

[0208] 1.42<Ninm<1.8 (21)

[0209] In order to obtain better characteristics, the lower limit of conditional formula (21) is more preferably set to 1.43, more preferably 1.44, more preferably 1.45, more preferably 1.46, more preferably 1.47, and more preferably 1.48. In order to obtain better characteristics, the upper limit of conditional formula (21) is more preferably set to 1.75, more preferably 1.7, more preferably 1.65, more preferably 1.6, more preferably 1.55, and more preferably 1.52.

[0210] In a configuration in which the first lens group G1 includes the L1nm lens, the L1n lens, and the L1p lens, the L1n lens is arranged at a position adjacent to the image side of the L1nm lens, and the L1p lens is arranged at a position closer to the image side than the L1n lens, the variable power optical system preferably includes a negative lens satisfying the following conditional expression (22). In this case, the negative lens satisfying the conditional expression (22) is preferably the L1n lens or a negative lens arranged adjacent to the image side of the L1n lens. Here, the refractive index of the negative lens arranged between the L1nm lens and the L1p lens with respect to the d-line is set to NG1n. By making the corresponding value of the conditional expression (22) not be less than the lower limit value, the L1n lens or the negative lens arranged adjacent to the image side of the L1n lens is easy to have sufficient negative power, which is conducive to good correction of distortion aberration. By making the corresponding value of conditional expression (22) not exceed the upper limit, the L1n lens or the negative lens arranged adjacent to the image side of the L1n lens can be easily configured without using a material with large dispersion, which is advantageous in correcting lateral chromatic aberration well.

[0211] 1.44<NG1n<1.8 (22)

[0212] In order to obtain better characteristics, the lower limit of conditional expression (22) is more preferably set to 1.48, more preferably 1.51, and more preferably 1.53. In order to obtain better characteristics, the upper limit of conditional expression (22) is more preferably set to 1.7, more preferably 1.65, and more preferably 1.6.

[0213] In a configuration where the zoom optical system includes a focus lens group, the zoom optical system preferably satisfies the following conditional expression (23). Here, the thickness of the focus lens group on the optical axis is set to Dfoc. In addition, the "thickness of the focus lens group on the optical axis" refers to the distance on the optical axis from the surface of the focus lens group closest to the object side to the surface of the focus lens group closest to the image side. As an example, in Figure 2 The thickness Dfoc is shown in FIG. By making the corresponding value of conditional expression (23) not less than the lower limit value, the thickness of the focus lens group will not become too small, which is conducive to ensuring the strength of the focus lens group. By making the corresponding value of conditional expression (23) not more than the upper limit value, the thickness of the focus lens group will not become too large, which is conducive to high-speed focusing.

[0214] 0.025<Dfoc / (ft×tanωt)<0.4 (23)

[0215] In order to obtain better characteristics, the lower limit of conditional expression (23) is more preferably set to 0.027, more preferably 0.029, and more preferably 0.03. In order to obtain better characteristics, the upper limit of conditional expression (23) is more preferably set to 0.35, more preferably 0.3, and more preferably 0.25.

[0216] In a structure in which the zoom optical system includes a focus lens group and the focus lens group includes one lens, the zoom optical system preferably satisfies the following conditional expression (24). Here, the Abbe number of the d-line reference of the lens constituting the focus lens group is set to vfoc. By making the corresponding value of the conditional expression (24) not be less than the lower limit value, it is beneficial to suppress the change of chromatic aberration during focusing. By making the corresponding value of the conditional expression (24) not be more than the upper limit value, it is possible to use materials with high obtainability, which is beneficial to realize a zoom optical system with suppressed spherical aberration and astigmatism.

[0217] 20<v foc<95 (24)

[0218] In order to obtain better characteristics, the lower limit value of the conditional formula (24) is more preferably set to 25, more preferably 34, more preferably 39, more preferably 43, more preferably 47, and more preferably 50. In order to obtain better characteristics, the upper limit value of the conditional formula (24) is more preferably set to 83, more preferably 78, more preferably 73, more preferably 68, more preferably 63, and more preferably 58.

[0219] The zoom optical system preferably satisfies the following conditional expression (25). Here, the maximum half viewing angle in the state of focusing on an infinitely distant object at the wide-angle end is set to ωw. The unit of ωw is set to degree. By making the corresponding value of conditional expression (25) not be less than the lower limit value, it is beneficial to wide angle. By making the corresponding value of conditional expression (25) not be more than the upper limit value, it is beneficial to miniaturization.

[0220] 40<ωw<70 (25)

[0221] In order to obtain better characteristics, the lower limit value of conditional expression (25) is more preferably set to 44, more preferably 46, and more preferably 48. In order to obtain better characteristics, the upper limit value of conditional expression (25) is more preferably set to 65, more preferably 60, and more preferably 56.

[0222] The zoom optical system preferably satisfies the following conditional expression (26). By making the corresponding value of conditional expression (26) not be less than the lower limit value, it is beneficial to achieve a high zoom ratio. By making the corresponding value of conditional expression (26) not be more than the upper limit value, it is beneficial to suppress the aberration change during zooming.

[0223] 1.5<ft / fw<3 (26)

[0224] In order to obtain better characteristics, the lower limit of conditional expression (26) is more preferably set to 1.6, more preferably 1.65, and more preferably 1.7. In order to obtain better characteristics, the upper limit of conditional expression (26) is more preferably set to 2.6, more preferably 2.3, and more preferably 2.1.

[0225] In the structure where the first lens group G1 includes the above-mentioned L1n lens, the variable power optical system preferably satisfies the following conditional expression (27). Here, the specific gravity of the L1n lens is set to ρL1n. By making the corresponding value of the conditional expression (27) not less than the lower limit value, it is easy to use a material with good availability. By making the corresponding value of the conditional expression (27) not more than the upper limit value, it is conducive to lightweighting of the optical system.

[0226] 0.75<ρL1n<3.2 (27)

[0227] In order to obtain better characteristics, the lower limit value of conditional formula (27) is more preferably set to 0.8, more preferably 0.82, more preferably 0.84, more preferably 0.86, more preferably 0.88, more preferably 0.9, and more preferably 0.92. In order to obtain better characteristics, the upper limit value of conditional formula (27) is more preferably set to 2.9, more preferably 2.6, more preferably 2.4, more preferably 2.2, more preferably 2, more preferably 1.8, and more preferably 1.6.

[0228] In a structure in which the first lens group G1 includes the above-mentioned L1n lens and the L1n lens is a lens made of only resin, the variable power optical system preferably satisfies the following conditional expression (28). Here, the center thickness of the L1n lens is dL1n. The thickness of the L1n lens in a direction parallel to the optical axis Z at the position of the maximum effective diameter of the image side surface of the L1n lens is dL1nh. As an example, Figure 2 The center thickness dL1n and the thickness dL1nh are shown in FIG. By making the corresponding value of conditional expression (28) not less than the lower limit value, it is advantageous to correct distortion aberration. By making the corresponding value of conditional expression (28) not more than the upper limit value, it is possible to suppress the reduction of the moldability of the L1n lens, which is advantageous in manufacturing. In addition, by making the corresponding value of conditional expression (28) not more than the upper limit value, it is possible to suppress the increase in the volume of the L1n lens itself, which is advantageous in weight reduction.

[0229] 1.1<dL1nh / dL1n<10 (28)

[0230] In order to obtain better characteristics, the lower limit of conditional formula (28) is more preferably set to 1.2, more preferably 1.3, more preferably 1.35, and more preferably 1.4. In order to obtain better characteristics, the upper limit of conditional formula (28) is more preferably set to 5, more preferably 4, more preferably 3.5, and more preferably 3.

[0231] In a structure where the L2nm lens is disposed at a position closer to the image side than the L1n lens, the variable magnification optical system preferably satisfies the following conditional formula (29). Here, the specific gravity of the L2nm lens is set to ρ L2nm. By making the corresponding value of the conditional formula (29) not less than the lower limit value, it is easy to use a material with good availability. By making the corresponding value of the conditional formula (29) not more than the upper limit value, it is conducive to lightweighting of the optical system.

[0232] 0.75<ρL2nm<3 (29)

[0233] In order to obtain better characteristics, the lower limit value of conditional formula (29) is more preferably set to 0.8, more preferably 0.82, more preferably 0.84, more preferably 0.86, more preferably 0.88, more preferably 0.9, and more preferably 0.92. In order to obtain better characteristics, the upper limit value of conditional formula (29) is more preferably set to 2.8, more preferably 2.6, more preferably 2.4, more preferably 2.2, more preferably 2, more preferably 1.8, and more preferably 1.6.

[0234] In a structure in which the above-mentioned L2nm lens is arranged closer to the image side than the L1n lens and the L2nm lens is a lens composed only of resin, the variable power optical system preferably satisfies the following conditional formula (30). Here, the center thickness of the L2nm lens is set to dL2nm. The thickness of the L2nm lens in a direction parallel to the optical axis Z at the position of the maximum effective diameter of the image side surface of the L2nm lens is set to dL2nmh. By making the corresponding value of the conditional formula (30) not be below the lower limit value, it is beneficial to correct the distortion aberration. By making the corresponding value of the conditional formula (30) not be above the upper limit value, the moldability of the L2nm lens can be suppressed from being reduced, so it is beneficial in manufacturing. In addition, by making the corresponding value of the conditional formula (30) not be above the upper limit value, the increase in the volume of the L2nm lens itself can be suppressed, so it is beneficial to lightweight.

[0235] 1.1<dL2nmh / dL2nm<10 (30)

[0236] In order to obtain better characteristics, the lower limit of conditional formula (30) is more preferably set to 1.13, more preferably 1.16, more preferably 1.18, and more preferably 1.2. In order to obtain better characteristics, the upper limit of conditional formula (30) is more preferably set to 5, more preferably 4, more preferably 3, and more preferably 2.5.

[0237] In the structure in which the first lens group G1 includes the above-mentioned L1nm lens, the variable magnification optical system preferably satisfies the following conditional formula (31). Here, the focal length of the L1nm lens is set to fl1nm. By making the corresponding value of the conditional formula (31) not less than the lower limit value, the negative focal length of the L1nm lens will not become too weak, so there is no need to increase the diameter of the L1nm lens, and the amount of light in the image periphery at the wide-angle end can be ensured. This is conducive to miniaturization. By making the corresponding value of the conditional formula (31) not more than the upper limit value, the negative focal length of the L1nm lens will not become too strong, so it is conducive to correcting the image curvature and distortion aberration at the wide-angle end.

[0238] 0.05<fw / |fL1nm|<2 (31)

[0239] In order to obtain better characteristics, the lower limit of conditional formula (31) is more preferably set to 0.1, more preferably 0.15, more preferably 0.2, and more preferably 0.27. In order to obtain better characteristics, the upper limit of conditional formula (31) is more preferably set to 1.5, more preferably 1.1, more preferably 0.7, and more preferably 0.55.

[0240] In a structure where the zoom optical system includes a focus lens group and an Lr lens disposed at a position closer to the image side than the focus lens group, the zoom optical system preferably satisfies the following conditional formula (32). Here, the specific gravity of the Lr lens is set to ρ Lr. By making the corresponding value of the conditional formula (32) not be less than the lower limit value, it is easy to use a material with good availability. By making the corresponding value of the conditional formula (32) not be more than the upper limit value, it is beneficial to the lightweight of the optical system.

[0241] 0.75<ρ Lr<3 (32)

[0242] In order to obtain better characteristics, the lower limit of conditional formula (32) is more preferably set to 0.8, more preferably 0.82, more preferably 0.84, more preferably 0.86, more preferably 0.88, more preferably 0.9, and more preferably 0.92. In order to obtain better characteristics, the upper limit of conditional formula (32) is more preferably set to 2.8, more preferably 2.6, more preferably 2.4, more preferably 2.2, more preferably 2, more preferably 1.8, and more preferably 1.6.

[0243] In the structure in which the first lens group G1 includes the above-mentioned L1nm lens, the variable power optical system preferably satisfies the following conditional expression (33). Here, the center thickness of the L1nm lens is set to dL1nm. The thickness of the L1nm lens in the direction parallel to the optical axis Z at the position of the maximum effective diameter of the image side surface of the L1nm lens is set to dL1nmh. As an example, Figure 2 The center thickness dL1nm and the thickness dL1nmh are shown in FIG. By making the corresponding value of conditional expression (33) not less than the lower limit value, it is advantageous to suppress distortion aberration at the wide-angle end. By making the corresponding value of conditional expression (33) not more than the upper limit value, the center thickness of the L1nm lens will not become too thin, which is advantageous to ensure the strength of the L1nm lens.

[0244] 2<dL1nmh / dL1nm<12 (33)

[0245] In order to obtain better characteristics, the lower limit value of conditional formula (33) is more preferably set to 3, more preferably 4, more preferably 5, and more preferably 5.5. In order to obtain better characteristics, the upper limit value of conditional formula (33) is more preferably set to 10, more preferably 9, more preferably 8, and more preferably 7.5.

[0246] The above-mentioned preferred structures and possible structures may be arbitrarily combined within the scope of no contradiction, and are preferably appropriately and selectively adopted according to the required specifications.

[0247] As an example, a preferred embodiment of the zoom optical system of the present invention includes, from the object side to the image side, a first lens group G1 having negative optical focal length, a second lens group G2 having positive optical focal length, and a subsequent group GR including one or more lens groups. When zooming, the first lens group G1 moves, and all intervals between adjacent lens groups change. One of the lens groups included in the subsequent group GR is a focusing lens group that moves along the optical axis Z when focusing, satisfying the above-mentioned conditional expressions (1), (2), (3), (4) and (5).

[0248] Next, embodiments of the variable magnification optical system of the present invention will be described with reference to the accompanying drawings. In addition, the reference symbols on each lens and each group in the cross-sectional view of each embodiment are used independently in each embodiment to avoid the complication of the description and drawings caused by the increase in the number of digits of the reference symbols. Therefore, even if the same reference symbols are marked in the drawings of different embodiments, they are not necessarily the same structure.

[0249] [Example 1]

[0250] The structure and movement trajectory of the variable magnification optical system of Example 1 are shown in Figure 1The diagramming method is as described above, so part of the repeated description is omitted here. The variable power optical system of Example 1 includes, from the object side to the image side, a first lens group G1 having negative optical power, a second lens group G2 having positive optical power, and a third lens group G3 having positive optical power. The subsequent group GR includes the third lens group G3. The first lens group G1 includes four lenses, lenses L11 to L14, from the object side to the image side. The second lens group G2 includes, from the object side to the image side, lens L21, an aperture stop St, and lenses L22 to L23. The third lens group G3 includes one lens, lens L31. Lens L12 is a compound aspheric lens.

[0251] When zooming from the wide-angle end to the telephoto end, all lens groups move along the optical axis Z by changing the intervals between adjacent lens groups. The focusing lens group includes the third lens group G3. When focusing from an infinitely distant object to the closest object, the third lens group G3 moves toward the object side, and the other lens groups are fixed relative to the image plane Sim. The anti-vibration group includes lens L21.

[0252] Regarding the variable power optical system of Example 1, basic lens data are shown in Table 1, specifications and variable surface intervals are shown in Table 2, and aspheric surface coefficients are shown in Table 3.

[0253] The following is a table of basic lens data. The "Sn" column shows the surface numbers when the surface closest to the object side is set as the first surface and the numbers are increased one 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 the surface adjacent to its image side. The "Nd" column shows the refractive index of each lens relative to the d-line. The "vd" column shows the Abbe number of the d-line reference of each lens. The "θg, F" column shows the partial dispersion ratio between the g-line and the F-line of each component. The "ED" column shows the effective diameter of each surface. The "NG1L+0.01×vG1L" column shows the corresponding values ​​of the conditional expression (4) of each lens. In addition, in the "ED" and "NG1L+0.01×vG1L" columns, values ​​are shown only for the relevant surfaces and lenses.

[0254] In addition, when the refractive index of a certain lens with respect to the g-line, F-line and C-line is respectively denoted as Ng, NF and NC and the partial dispersion ratio between the g-line and F-line of the lens is denoted as θg,F, θg,F is defined by the following formula.

[0255] θg, F = (Ng-NF) / (NF-NC)

[0256] The "d line", "C line", "F line" and "g line" described in this specification are bright lines, the wavelength of the d line is considered to be 587.56nm (nanometers), the wavelength of the C line is considered to be 656.27nm (nanometers), the wavelength of the F line is considered to be 486.13nm (nanometers), and the wavelength of the g line is considered to be 435.84nm (nanometers).

[0257] In the table of basic lens data, the sign of the radius of curvature of the surface that makes the convex shape face the object side is set to positive, and the sign of the radius of curvature of the surface that makes the convex shape face the image side is set to negative. In Table 1, the surface number and the term (St) are marked in the surface number column corresponding to the aperture stop St. The value at the bottom of the D column in the table is the interval between the surface closest to the image side in the table and the image surface Sim. Regarding the variable surface interval when changing magnification, the symbol DD[] is used, and the surface number on the object side of the interval is marked in [] and recorded in the surface interval column.

[0258] In Table 2, the zoom ratio Zr, focal length f, back focal length Bf, open F value FNo., maximum full viewing angle 2ω and variable surface interval are shown based on the d-line reference. When the zoom optical system is a zoom lens, the zoom ratio has the same meaning as the zoom factor. The [°] in the 2ω column indicates the unit is degree. In Table 2, the values ​​of the wide-angle end state, the middle focal length state and the telephoto end state are shown in the columns marked "Wide", "Middle" and "Tele", respectively.

[0259] In the basic lens data, the surface number of the aspheric surface is marked with an * sign, and the value of the paraxial curvature radius is recorded in the curvature radius column of the aspheric surface. In Table 3, the surface number of the aspheric surface is shown in the Sn row, and the numerical values ​​of the aspheric coefficients of each aspheric surface are shown in the KA and Am rows. In addition, m in Am is an integer greater than 3 and varies depending on the surface. For example, on the 5th surface of Example 1, m=4, 6, 8, 10. The numerical values ​​of the aspheric coefficients in Table 3 are "E±n" (n: integer) means "×10 ±n KA and Am are aspherical coefficients in the aspherical formula represented by the following formula.

[0260] Zd=C×h 2 / {1+(1-KA×C 2 ×h 2 ) 1 / 2}+∑Am×h m

[0261] in,

[0262] Zd: depth of aspheric surface (the length of the perpendicular line from a point on the aspheric surface at height h to a plane tangent to the vertex of the aspheric surface and perpendicular to the optical axis Z);

[0263] h: height (the distance from the optical axis Z to the lens surface);

[0264] C: the reciprocal of the paraxial radius of curvature;

[0265] KA, Am: Aspheric coefficients,

[0266] The ∑ of the aspherical form refers to the sum related to m.

[0267] In the data of each table, degrees are used as the unit of angle and millimeters are used as the unit of length, but since the optical system can be used at either a magnified or reduced scale, other appropriate units can also be used. In addition, in each table shown below, the values ​​rounded to a predetermined number of digits are recorded.

[0268] [Table 1]

[0269] Example 1

[0270]

[0271]

[0272] [Table 2]

[0273] Example 1

[0274] Wide Middle Tele Zr 1.0 1.4 1.8 f 14.65 20.72 26.38 Bf 20.66 23.74 29.00 FNo. 5.15 5.97 6.59 2ω[°] 97.4 68.2 54.6 DD[9] 23.87 10.70 2.52 DD

[16] 8.81 12.75 12.76 DD

[18] 20.66 23.74 29.00

[0275] [Table 3]

[0276] Example 1

[0277] Sn 5 6 7 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 -4.0349758E-05 -8.5452165E-05 -6.0208060E-05 A6 -8.4465208E-08 3.7294703E-06 3.6012803E-06 A8 3.3396531E-09 -2.6378718E-08 -2.4922830E-08 A10 -2.2208075E-11 6.3253528E-11 4.9413143E-11

[0278] Sn 17 18 KA 1.0000000E+00 1.0000000E+00 A4 -2.1555952E-04 -5.6523145E-05 A6 1.3739246E-06 4.8666335E-07 A8 -2.0564140E-07 -6.9913046E-08 A10 6.9480074E-10 -1.6107487E-11

[0279] exist Figure 4 , various aberration diagrams are shown for a state where the variable power optical system of Example 1 is focused on an object at infinity. Figure 4 In the figure, spherical aberration, astigmatism, distortion and chromatic aberration of magnification are shown from left to right. Figure 4In the figure, the aberrations at the wide-angle end state are shown in the upper section marked with "Wide", the aberrations at the intermediate focal length state are shown in the middle section marked with "Middle", and the aberrations at the telephoto end state are shown in the lower section marked with "Tele". In the spherical aberration diagram, aberrations under the d-line, C-line and F-line are shown with solid lines, long dashed lines and short dashed lines, respectively. In the astigmatism diagram, aberrations under the d-line in the sagittal direction are shown with solid lines, and aberrations under the d-line in the meridional direction are shown with short dashed lines. In the distortion diagram, aberrations under the d-line are shown with solid lines. In the lateral chromatic aberration diagram, aberrations under the C-line and F-line are shown with long dashed lines and short dashed lines, respectively. In the spherical aberration diagram, the value of the open F value is shown after FNo.=. In the other aberration diagrams, the value of the maximum half viewing angle is shown after ω=.

[0280] Unless otherwise specified, the symbols, meanings, recording methods and graphical representation methods of various data related to the above-mentioned embodiment 1 are basically the same in the following embodiments, and therefore repeated descriptions are omitted below.

[0281] [Example 2]

[0282] The structure and movement trajectory of the variable magnification optical system of Example 2 are shown in FIG. Figure 5 . The variable power optical system of Example 2 includes, from the object side to the image side, a first lens group G1 having negative power, a second lens group G2 having positive power, and a third lens group G3 having positive power. The subsequent group GR includes the third lens group G3. The first lens group G1 includes, from the object side to the image side, three lenses, namely, lenses L11 to L13. The second lens group G2 includes, from the object side to the image side, lens L21, an aperture stop St, and lenses L22 to L24. The third lens group G3 includes one lens, namely, lens L31. Lens L11 is a compound aspherical lens.

[0283] When zooming from the wide-angle end to the telephoto end, all lens groups move along the optical axis Z by changing the intervals between adjacent lens groups. The focusing lens group includes the third lens group G3. When focusing from an infinitely distant object to the closest object, the third lens group G3 moves toward the object side, and the other lens groups are fixed relative to the image plane Sim. The anti-vibration group includes lens L21.

[0284] Regarding the variable magnification optical system of Example 2, basic lens data is shown in Table 4, specifications and variable surface intervals are shown in Table 5, aspheric coefficients are shown in Table 6, and various aberration diagrams are shown in Table 8. Figure 6 middle.

[0285] [Table 4]

[0286] Example 2

[0287]

[0288] [Table 5]

[0289] Example 2

[0290] Wide Middle Tele Zr 1.0 1.4 1.8 f 14.15 20.01 25.47 Bf 18.97 24.67 27.98 FNo. 5.16 5.91 6.73 2ω[°] 100.6 73.6 58.6 DD[7] 20.11 7.25 1.50 DD

[16] 7.51 7.64 11.34 DD

[18] 18.97 24.67 27.98

[0291] [Table 6]

[0292] Example 2

[0293] Sn 3 4 5 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 -1.4144228E-06 -7.1608890E-05 -8.4320691E-05 A6 -4.0237638E-07 3.1754587E-06 3.9763276E-06 A8 -1.4771692E-09 -2.0972651E-08 -2.7712795E-08 A10 2.4999494E-11 6.3029066E-11 6.9669402E-11

[0294] Sn 17 18 KA 1.0000000E+00 1.0000000E+00 A4 -3.0312463E-04 -1.1704879E-04 A6 -3.6724154E-07 -1.3119162E-06 A8 1.1031744E-08 3.9493446E-08 A10 -1.0668581E-09 -6.9261491E-10

[0295] [Example 3]

[0296] The structure and movement trajectory of the variable magnification optical system of Example 3 are shown in FIG. Figure 7 . The variable power optical system of Example 3 includes, from the object side to the image side, a first lens group G1 having negative power, a second lens group G2 having positive power, and a third lens group G3 having negative power. The subsequent group GR includes the third lens group G3. The first lens group G1 includes, from the object side to the image side, three lenses, namely, lenses L11 to L13. The second lens group G2 includes, from the object side to the image side, lens L21, an aperture stop St, and lenses L22 to L25. The third lens group G3 includes one lens, namely, lens L31.

[0297] When zooming from the wide-angle end to the telephoto end, all lens groups move along the optical axis Z by changing the intervals between adjacent lens groups. The focusing lens group includes the third lens group G3. When focusing from an infinitely distant object to the closest object, the third lens group G3 moves toward the image side, and the other lens groups are fixed relative to the image plane Sim. The anti-vibration group includes lens L21.

[0298] Regarding the variable magnification optical system of Example 3, basic lens data are shown in Table 7, specifications and variable surface intervals are shown in Table 8, aspheric coefficients are shown in Table 9, and various aberration diagrams are shown in Table 10. Figure 8 middle.

[0299] [Table 7]

[0300] Example 3

[0301]

[0302] [Table 8]

[0303] Example 3

[0304] Wide Middle Tele Zr 1.0 1.4 1.7 f 13.40 18.95 22.78 Bf 22.56 24.68 26.09 FNo. 5.12 5.59 5.93 2ω[°] 102.8 73.8 62.2 DD[6] 22.21 9.53 4.35 DD

[15] 1.46 3.01 4.01 DD

[17] 22.56 24.68 26.09

[0305] [Table 9]

[0306] Example 3

[0307] Sn 3 4 5 6 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 4.3733536E-05 4.8505410E-06 -1.4179706E-04 -1.2747392E-04 A6 -9.9772455E-07 -1.2096654E-06 -1.2463577E-06 -1.0039121E-06 A8 4.9400215E-09 -2.8986034E-08 -1.6206553E-08 1.0187453E-08 A10 0.0000000E+00 1.6417486E-10 1.9092893E-10 -1.7909059E-11

[0308] Sn 7 8 15 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 -3.5017847E-04 -2.4506721E-04 1.1469235E-04 A6 -8.7598411E-06 -9.2559332E-06 5.8915653E-07 A8 1.9675551E-07 2.9448744E-07 -1.1854134E-08 A10 -2.7924194E-08 -2.5936909E-08 1.9541000E-10

[0309] [Example 4]

[0310] The structure and movement trajectory of the variable magnification optical system of Example 4 are shown in FIG. Fig. 9 . The variable power optical system of Example 4 includes, from the object side to the image side, a first lens group G1 having negative power, a second lens group G2 having positive power, and a third lens group G3 having negative power. The subsequent group GR includes the third lens group G3. The first lens group G1 includes, from the object side to the image side, three lenses, namely, lenses L11 to L13. The second lens group G2 includes, from the object side to the image side, a lens L21, an aperture stop St, and lenses L22 to L26. The third lens group G3 includes one lens, namely, lens L31.

[0311] When zooming from the wide-angle end to the telephoto end, all lens groups move along the optical axis Z by changing the intervals between adjacent lens groups. The focusing lens group includes the third lens group G3. When focusing from an infinitely distant object to the closest object, the third lens group G3 moves toward the image side, and the other lens groups are fixed relative to the image plane Sim. The anti-vibration group includes lens L21.

[0312] Regarding the variable magnification optical system of Example 4, basic lens data is shown in Table 10, specifications and variable surface intervals are shown in Table 11, aspheric coefficients are shown in Table 12, and various aberration diagrams are shown in Table 13. Fig.10 .

[0313] [Table 10]

[0314] Example 4

[0315]

[0316] [Table 11]

[0317] Example 4

[0318] Wide Middle Tele Zr 1.0 1.4 1.9 f 13.39 18.94 25.45 Bf 25.77 28.05 28.90 FNo. 5.15 5.87 6.59 2ω[°] 102.6 74.4 56.6 DD[6] 20.95 9.31 1.17 DD

[17] 1.26 3.07 5.71 DD

[19] 25.77 28.05 28.90

[0319] [Table 12]

[0320] Example 4

[0321] Sn 3 4 5 6 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 1.1262202E-04 3.1126466E-05 -2.4898899E-04 -2.2590078E-04 A6 -1.1520767E-06 -6.6982695E-07 -1.3418263E-06 -1.0207478E-06 A8 4.7554445E-09 -3.5239180E-08 -1.6631813E-08 1.1625818E-08 A10 0.0000000E+00 1.3703850E-10 1.9110746E-10 -2.5814616E-11

[0322] Sn 7 8 17 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 -2.9302824E-04 -2.0076066E-04 8.6766715E-05 A6 -3.4185996E-06 -1.9502984E-06 5.9211452E-07 A8 1.1454678E-08 -1.1606462E-08 -1.1963056E-08 A10 -3.5670603E-09 -1.7431155E-09 1.9541000E-10

[0323] [Example 5]

[0324] The structure and movement trajectory of the variable magnification optical system of Example 5 are shown in FIG. Fig.11. The variable power optical system of Example 5 includes, from the object side to the image side, a first lens group G1 having negative power, a second lens group G2 having positive power, a third lens group G3 having positive power, and a fourth lens group G4 having negative power. The subsequent group GR includes two lens groups, namely, the third lens group G3 and the fourth lens group G4. The first lens group G1 includes, from the object side to the image side, three lenses, namely, lenses L11 to L13. The second lens group G2 includes, from the object side to the image side, three lenses, namely, lenses L21 to L23, and an aperture stop St. The third lens group G3 includes one lens, namely, lens L31. The fourth lens group G4 includes one lens, namely, lens L41.

[0325] When zooming from the wide-angle end to the telephoto end, all lens groups move along the optical axis Z by changing the intervals between adjacent lens groups. The focusing lens group includes the third lens group G3. When focusing from an infinitely distant object to the closest object, the third lens group G3 moves toward the object side, and the other lens groups are fixed relative to the image plane Sim. The anti-vibration group includes three lenses, lenses L21 to L23.

[0326] Regarding the variable magnification optical system of Example 5, basic lens data is shown in Table 13, specifications and variable surface intervals are shown in Table 14, aspheric coefficients are shown in Table 15, and various aberration diagrams are shown in Table 16. Fig.12 middle.

[0327] [Table 13]

[0328] Example 5

[0329]

[0330] [Table 14]

[0331] Example 5

[0332] Wide Middle Tele Zr 1.0 1.4 2.1 f 12.36 17.48 25.95 Bf 17.13 21.69 22.58 FNo. 5.11 5.76 6.72 2ω[°] 107.0 79.6 55.2 DD[6] 25.21 13.22 3.05 DD

[13] 14.14 11.77 9.97 DD

[15] 1.36 3.77 10.55 DD

[17] 17.13 21.69 22.58

[0333] [Table 15]

[0334] Example 5

[0335] Sn 3 4 16 17 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 3.6033378E-05 6.6795711E-06 3.9122941E-05 1.1591373E-04 A6 -2.1999331E-07 -3.6427945E-07 1.0989111E-06 6.0773125E-07 A8 4.8822084E-10 -3.2165712E-10 -3.8622431E-08 -1.3493986E-08 A10 -1.0589209E-12 -5.4220809E-12 4.6690187E-10 1.0966094E-10 A12 1.4071535E-15 3.9724374E-15 -2.4619952E-12 -4.8517534E-13

[0336] Sn 7 8 KA 1.0000000E+00 1.0000000E+00 A4 1.4050995E-05 5.6135431E-05 A6 7.4115657E-07 4.2733355E-07 A8 -1.7581017E-08 1.2037813E-08 A10 8.7649421E-10 3.1110738E-10

[0337] [Example 6]

[0338] The structure and movement trajectory of the variable magnification optical system of Example 6 are shown in FIG. Fig.13. The variable power optical system of Example 6 includes, from the object side to the image side, a first lens group G1 having negative power, a second lens group G2 having positive power, a third lens group G3 having positive power, and a fourth lens group G4 having negative power. The subsequent group GR includes two lens groups, namely, the third lens group G3 and the fourth lens group G4. The first lens group G1 includes, from the object side to the image side, four lenses, namely, lenses L11 to L14. The second lens group G2 includes, from the object side to the image side, three lenses, namely, lenses L21 to L23, and an aperture stop St. The third lens group G3 includes one lens, namely, lens L31. The fourth lens group G4 includes one lens, namely, lens L41. Lens L12 is a compound aspherical lens.

[0339] When zooming from the wide-angle end to the telephoto end, the fourth lens group G4 is fixed relative to the image plane Sim, and the other lens groups move along the optical axis Z by changing the intervals between adjacent lens groups. The focusing lens group includes the third lens group G3. When focusing from an infinitely distant object to the closest object, the third lens group G3 moves toward the object side, and the other lens groups are fixed relative to the image plane Sim. The anti-vibration group includes three lenses, namely, lenses L21 to L23. In addition, Fig.13 In FIG. 1 , a straight dotted line in the up-down direction is shown instead of a solid arrow of a moving track for a lens group fixed relative to the image plane Sim during zooming. This method of illustrating a lens group fixed relative to the image plane Sim during zooming is also the same in the following embodiments.

[0340] Regarding the variable magnification optical system of Example 6, basic lens data is shown in Table 16, specifications and variable surface intervals are shown in Table 17, aspheric coefficients are shown in Table 18, and various aberration diagrams are shown in Table 19. Fig.14 middle.

[0341] [Table 16]

[0342] Example 6

[0343]

[0344] [Table 17]

[0345] Example 6

[0346] Wide Middle Tele Zr 1.0 1.4 2.2 f 11.38 16.09 25.03 Bf 17.03 17.03 17.03 FNo. 5.11 5.86 6.96 2ω[°] 111.0 82.2 55.4 DD[9] 21.67 12.01 1.90 DD

[16] 11.65 14.69 9.57 DD

[18] 1.29 5.31 15.99

[0347] [Table 18]

[0348] Example 6

[0349] Sn 5 6 7 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 -1.5349362E-05 -7.9562570E-06 -5.1201558E-05 A6 2.1763740E-07 1.9020094E-07 -3.8333535E-07 A8 -1.4083218E-10 -3.2570118E-09 1.5249139E-09 A10 8.7175931E-13 3.5023109E-11 -1.2541753E-11 A12 1.7117746E-14 -1.7793642E-13 -4.2603422E-14

[0350] Sn 10 11 KA 1.0000000E+00 1.0000000E+00 A4 2.0693933E-05 9.3486498E-05 A6 -2.0028603E-07 7.2501884E-07 A8 2.9531644E-08 -4.8399286E-08 A10 2.1111292E-11 3.5882195E-09

[0351] Sn 19 20 KA 1.0000000E+00 1.0000000E+00 A4 3.3136192E-05 1.1658830E-04 A6 7.5953225E-07 1.3146276E-07 A8 -3.5954715E-08 -9.2076502E-09 A10 5.4638274E-10 1.2984352E-10 A12 -3.4392209E-12 -7.2127433E-13

[0352] [Example 7]

[0353] The structure and movement trajectory of the variable magnification optical system of Example 7 are shown in FIG. Fig.15 . The variable power optical system of Example 7 includes, from the object side to the image side, a first lens group G1 having negative power, a second lens group G2 having positive power, a third lens group G3 having positive power, and a fourth lens group G4 having negative power. The subsequent group GR includes two lens groups, namely, the third lens group G3 and the fourth lens group G4. The first lens group G1 includes, from the object side to the image side, four lenses, namely, lenses L11 to L14. The second lens group G2 includes, from the object side to the image side, three lenses, namely, lenses L21 to L23, and an aperture stop St. The third lens group G3 includes, from the object side to the image side, two lenses, namely, lenses L31 to L32. The fourth lens group G4 includes one lens, namely, lens L41.

[0354] When zooming from the wide-angle end to the telephoto end, all lens groups move along the optical axis Z by changing the intervals between adjacent lens groups. The focusing lens group includes the third lens group G3. When focusing from an infinitely distant object to the closest object, the third lens group G3 moves toward the object side, and the other lens groups are fixed relative to the image plane Sim. The anti-vibration group includes three lenses, lenses L21 to L23.

[0355] Regarding the variable magnification optical system of Example 7, basic lens data is shown in Table 19, specifications and variable surface intervals are shown in Table 20, aspheric coefficients are shown in Table 21, and various aberration diagrams are shown in Table 23. Fig.16 .

[0356] [Table 19]

[0357] Example 7

[0358]

[0359] [Table 20]

[0360] Example 7

[0361] Wide Middle Tele Zr 1.0 1.4 2.3 f 11.36 16.06 26.12 Bf 17.53 21.76 18.93 FNo. 5.11 5.73 6.63 2ω[°] 111.6 84.8 53.4 DD[8] 23.17 12.46 0.67 DD

[15] 12.70 11.40 9.84 DD

[18] 1.25 3.15 14.19 DD

[20] 17.53 21.76 18.93

[0362] [Table 21]

[0363] Example 7

[0364] Sn 5 6 19 20 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 -5.9755217E-06 -4.4705476E-05 6.9220809E-05 1.4805795E-04 A6 6.1678896E-08 -2.2801537E-07 7.9362784E-07 1.9672505E-07 A8 -2.9075639E-09 7.8969626E-10 -3.7402804E-08 -9.4639577E-09 A10 3.5816906E-11 -8.9221503E-12 6.1379722E-10 1.5122740E-10 A12 -1.8225297E-13 -5.3187853E-14 -3.9212122E-12 -8.6798362E-13

[0365] Sn 9 10 KA 1.0000000E+00 1.0000000E+00 A4 1.6138717E-05 6.2618362E-05 A6 -1.2522888E-07 7.4092425E-07 A8 3.5149200E-08 -2.0139856E-08 A10 -4.4555075E-10 1.2338528E-09

[0366] [Example 8]

[0367] The structure and movement trajectory of the variable magnification optical system of Example 8 are shown in FIG. Fig.17. The variable power optical system of Example 8 includes, from the object side to the image side, a first lens group G1 having negative power, a second lens group G2 having positive power, a third lens group G3 having positive power, and a fourth lens group G4 having negative power. The subsequent group GR includes two lens groups, namely, the third lens group G3 and the fourth lens group G4. The first lens group G1 includes, from the object side to the image side, four lenses, namely, lenses L11 to L14. The second lens group G2 includes, from the object side to the image side, three lenses, namely, lenses L21 to L23, and an aperture stop St. The third lens group G3 includes one lens, namely, lens L31. The fourth lens group G4 includes one lens, namely, lens L41.

[0368] When zooming from the wide-angle end to the telephoto end, the fourth lens group G4 is fixed relative to the image plane Sim, and the other lens groups move along the optical axis Z by changing the intervals between adjacent lens groups. The focusing lens group includes the third lens group G3. When focusing from an infinitely distant object to the closest object, the third lens group G3 moves toward the object side, and the other lens groups are fixed relative to the image plane Sim. The anti-vibration group includes three lenses, namely, lenses L21 to L23.

[0369] Regarding the variable magnification optical system of Example 8, basic lens data is shown in Table 22, specifications and variable surface intervals are shown in Table 23, aspheric coefficients are shown in Table 24, and various aberration diagrams are shown in Table 25. Fig.18 .

[0370] [Table 22]

[0371] Example 8

[0372]

[0373]

[0374] [Table 23]

[0375] Example 8

[0376] Wide Middle Tele Zr 1.0 1.4 2.3 f 11.73 16.58 26.97 Bf 16.73 16.73 16.73 FNo. 5.11 5.85 7.43 2ω[°] 110.0 81.0 50.2 DD[8] 20.84 10.93 1.65 DD

[15] 12.49 12.43 9.86 DD

[17] 1.49 7.15 19.40

[0377] [Table 24]

[0378] Example 8

[0379] Sn 5 6 18 19 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 -2.8964777E-05 -6.1246923E-05 3.2980077E-04 3.4349034E-04 A6 9.9230973E-08 2.5957763E-08 6.7804200E-07 7.7831456E-07 A8 1.0287633E-10 6.1825164E-10 -4.0067226E-08 -1.5671603E-08 A10 1.0082632E-11 1.0949247E-11 4.7546341E-10 9.3739793E-11 A12 -8.5746587E-14 -1.4831158E-13 -2.1384872E-12 -1.2606162E-13

[0380] Sn 9 10 KA 1.0000000E+00 1.0000000E+00 A4 2.8895245E-06 7.3488641E-05 A6 6.9658700E-07 1.6492673E-06 A8 7.0862634E-08 4.9045973E-08 A10 -2.2426313E-09 -1.5099422E-09

[0381] [Example 9]

[0382] The structure and movement trajectory of the variable magnification optical system of Example 9 are shown in FIG. Fig.19. The variable power optical system of Example 9 includes, from the object side to the image side, a first lens group G1 having negative power, a second lens group G2 having positive power, a third lens group G3 having positive power, and a fourth lens group G4 having negative power. The subsequent group GR includes two lens groups, namely, the third lens group G3 and the fourth lens group G4. The first lens group G1 includes, from the object side to the image side, three lenses, namely, lenses L11 to L13. The second lens group G2 includes one lens, namely, lens L21. The third lens group G3 includes, from the object side to the image side, five lenses, namely, aperture stop St and lenses L31 to L35. The fourth lens group G4 includes one lens, namely, lens L41.

[0383] When zooming from the wide-angle end to the telephoto end, all lens groups move along the optical axis Z by changing the intervals between adjacent lens groups. The focusing lens group includes the fourth lens group G4. When focusing from an infinitely distant object to the closest object, the fourth lens group G4 moves toward the image side, and the other lens groups are fixed relative to the image plane Sim. The anti-vibration group includes the second lens group G2.

[0384] Regarding the variable magnification optical system of Example 9, basic lens data are shown in Table 25, specifications and variable surface intervals are shown in Table 26, aspheric coefficients are shown in Table 27, and various aberration diagrams are shown in Table 28. Fig. 20 .

[0385] [Table 25]

[0386] Example 9

[0387]

[0388]

[0389] [Table 26]

[0390] Example 9

[0391] Wide Middle Tele Zr 1.0 1.4 2.1 f 12.22 17.28 25.67 Bf 25.48 29.15 36.13 FNo. 5.16 5.80 6.96 2ω[°] 108.6 79.8 57.2 DD[6] 20.48 9.46 1.86 DD[8] 5.25 4.33 1.87 DD

[17] 0.77 1.64 2.43 DD

[19] 25.48 29.15 36.13

[0392] [Table 27]

[0393] Example 9

[0394] Sn 3 4 5 6 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 2.4609490E-04 1.6579350E-04 -2.2817861E-04 -2.3758865E-04 A6 -1.2458317E-06 6.5067691E-07 -7.9652574E-08 -4.9091030E-07 A8 2.8181619E-09 -2.0117588E-08 -9.4334848E-09 7.1129287E-09 A10 0.0000000E+00 -2.7063806E-11 6.7249834E-11 -1.9223715E-11

[0395] Sn 7 8 17 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 -4.1132025E-04 -2.5549446E-04 1.4348698E-04 A6 -5.4718127E-06 -3.6337742E-06 9.3304013E-07 A8 -2.0173520E-08 2.4117375E-09 -2.0844378E-09 Ai0 -6.4383003E-09 -3.5250322E-09 1.9541000E-10

[0396] [Example 10]

[0397] The structure and movement trajectory of the variable magnification optical system of Example 10 are shown in FIG. Fig.21. The variable power optical system of Example 10 includes, from the object side to the image side, a first lens group G1 having negative optical power, a second lens group G2 having positive optical power, a third lens group G3 having negative optical power, and a fourth lens group G4 having positive optical power. The subsequent group GR includes two lens groups, namely, the third lens group G3 and the fourth lens group G4. The first lens group G1 includes, from the object side to the image side, three lenses, namely, lenses L11 to L13. The second lens group G2 includes, from the object side to the image side, lens L21, an aperture stop St, and lenses L22 to L25. The third lens group G3 includes one lens, namely, lens L31. The fourth lens group G4 includes one lens, namely, lens L41.

[0398] When zooming from the wide-angle end to the telephoto end, all lens groups move along the optical axis Z by changing the intervals between adjacent lens groups. The focusing lens group includes the third lens group G3. When focusing from an infinitely distant object to the closest object, the third lens group G3 moves toward the image side, and the other lens groups are fixed relative to the image plane Sim. The anti-vibration group includes lens L21.

[0399] Regarding the variable magnification optical system of Example 10, basic lens data are shown in Table 28, specifications and variable surface intervals are shown in Table 29, aspheric coefficients are shown in Table 30, and various aberration diagrams are shown in Table 31. Fig. 22 .

[0400] [Table 28]

[0401] Example 10

[0402]

[0403]

[0404] [Table 29]

[0405] Example 10

[0406] Wide Middle Tele Zr 1.0 1.4 1.9 f 12.86 18.19 24.05 Bf 18.88 14.61 14.29 FNo. 5.15 6.00 6.64 2ω[°] 105.2 76.8 58.6 DD[6] 21.70 10.32 1.27 DD

[15] 3.58 5.49 9.03 DD

[17] 4.90 11.76 10.94 DD

[19] 18.88 14.61 14.29

[0407] [Table 30]

[0408] Example 10

[0409] Sn 3 4 5 6 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 5.0921846E-05 1.3240384E-05 -1.3351261E-04 -1.2424635E-04 A6 4.3327815E-07 5.5524520E-07 -9.6003628E-07 -4.5058342E-07 A8 -1.0017594E-08 -1.4917513E-08 -3.1246901E-09 4.6203345E-09 A10 4.4859494E-11 -1.2182318E-10 1.0283004E-10 1.0505720E-11

[0410] Sn 7 8 14 15 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 -2.5777300E-04 -2.1547724E-04 2.2894507E-05 2.0034505E-04 A6 -2.6113718E-06 -1.6646947E-06 -2.4271520E-06 -2.8651768E-06 A8 -2.5110334E-08 -6.2767732E-08 -1.1525576E-07 -1.1327398E-07 A10 -3.7004710E-09 -1.9842423E-09 1.2049261E-08 1.2568097E-08

[0411] [Example 11]

[0412] The structure and movement trajectory of the variable magnification optical system of Example 11 are shown in FIG. Fig.23. The variable power optical system of Example 11 includes, from the object side to the image side, a first lens group G1 having negative optical power, a second lens group G2 having positive optical power, a third lens group G3 having negative optical power, and a fourth lens group G4 having positive optical power. The subsequent group GR includes two lens groups, namely, the third lens group G3 and the fourth lens group G4. The first lens group G1 includes, from the object side to the image side, three lenses, namely, lenses L11 to L13. The second lens group G2 includes, from the object side to the image side, lens L21, an aperture stop St, and lenses L22 to L26. The third lens group G3 includes one lens, namely, lens L31. The fourth lens group G4 includes one lens, namely, lens L41.

[0413] When zooming from the wide-angle end to the telephoto end, all lens groups move along the optical axis Z by changing the intervals between adjacent lens groups. The focusing lens group includes the third lens group G3. When focusing from an infinitely distant object to the closest object, the third lens group G3 moves toward the image side, and the other lens groups are fixed relative to the image plane Sim. The anti-vibration group includes lens L21.

[0414] Regarding the variable magnification optical system of Example 11, basic lens data is shown in Table 31, specifications and variable surface intervals are shown in Table 32, aspheric coefficients are shown in Table 33, and various aberration diagrams are shown in Table 34. Fig.24 .

[0415] [Table 31]

[0416] Embodiment 11

[0417]

[0418] [Table 32]

[0419] Embodiment 11

[0420] Wide Middle Tele Zr 1.0 1.4 1.9 f 12.21 17.27 23.68 Bf 18.88 19.81 16.46 FNo. 5.16 5.87 6.93 2ω[°] 108.6 79.4 60.6 DD[6] 18.61 7.76 1.39 DD

[17] 1.23 2.88 4.54 DD

[19] 4.88 6.04 12.93 DD

[21] 18.88 19.81 16.46

[0421] [Table 33]

[0422] Embodiment 11

[0423] Sn 3 4 5 6 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 1.5877090E-04 6.6891819E-05 -2.4561559E-04 -2.4428915E-04 A6 -1.1277355E-06 -5.0349980E-07 -9.7111551E-07 -1.0468202E-06 A8 3.6422008E-09 -1.2516224E-08 -7.9864755E-09 1.5049568E-08 A10 0.0000000E+00 -1.1669958E-10 1.2245401E-10 -5.2599700E-11

[0424] Sn 7 8 17 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 -1.4300874E-04 -1.1721099E-04 1.2895451E-04 A6 -1.2583880E-07 -1.4729359E-07 2.9329475E-07 A8 -3.8842063E-09 3.6461431E-08 -7.2870323E-09 A10 -4.8701887E-10 -1.7166805E-09 1.9541000E-10

[0425] [Example 12]

[0426] The structure and movement trajectory of the variable magnification optical system of Example 12 are shown in FIG. Fig.25. The variable power optical system of Example 12 includes, from the object side to the image side, a first lens group G1 having negative power, a second lens group G2 having positive power, a third lens group G3 having negative power, and a fourth lens group G4 having positive power. The subsequent group GR includes two lens groups, namely, the third lens group G3 and the fourth lens group G4. The first lens group G1 includes, from the object side to the image side, three lenses, namely, lenses L11 to L13. The second lens group G2 includes, from the object side to the image side, lens L21, an aperture stop St, and lenses L22 to L27. The third lens group G3 includes one lens, namely, lens L31. The fourth lens group G4 includes one lens, namely, lens L41.

[0427] When zooming from the wide-angle end to the telephoto end, all lens groups move along the optical axis Z by changing the intervals between adjacent lens groups. The focusing lens group includes the third lens group G3. When focusing from an infinitely distant object to the closest object, the third lens group G3 moves toward the image side, and the other lens groups are fixed relative to the image plane Sim. The anti-vibration group includes lens L21.

[0428] Regarding the variable magnification optical system of Example 12, basic lens data is shown in Table 34, specifications and variable surface intervals are shown in Table 35, aspheric coefficients are shown in Table 36, and various aberration diagrams are shown in Table 37. Fig.26 .

[0429] [Table 34]

[0430] Example 12

[0431]

[0432] [Table 35]

[0433] Example 12

[0434] Wide Middle Tele Zr 1.0 1.4 2.3 f 12.36 17.48 28.42 Bf 18.16 19.09 28.35 FNo. 4.12 5.02 6.76 2ω[°] 107.6 82.4 54.6 DD[6] 19.01 10.52 1.55 DD

[18] 1.29 2.14 3.45 DD

[20] 4.89 10.34 14.96 DD

[22] 18.16 19.09 28.35

[0435] [Table 36] Example 12

[0436]

[0437]

[0438] Sn 7 8 18 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 -3.6669886E-05 -3.2797319E-05 1.3752563E-04 A6 3.2617785E-07 5.0050357E-07 3.5325374E-07 A8 -6.2280553E-09 -1.2096583E-08 -2.0783381E-08 A10 4.1526666E-10 4.5940436E-10 1.9541000E-10

[0439] [Example 13]

[0440] The structure and movement trajectory of the variable magnification optical system of Example 13 are shown in FIG. Fig. 27. The variable power optical system of Example 13 includes, from the object side to the image side, a first lens group G1 having negative optical power, a second lens group G2 having positive optical power, a third lens group G3 having negative optical power, and a fourth lens group G4 having negative optical power. The subsequent group GR includes two lens groups, namely, the third lens group G3 and the fourth lens group G4. The first lens group G1 includes, from the object side to the image side, three lenses, namely, lenses L11 to L13. The second lens group G2 includes, from the object side to the image side, lens L21, an aperture stop St, and lenses L22 to L25. The third lens group G3 includes one lens, namely, lens L31. The fourth lens group G4 includes one lens, namely, lens L41.

[0441] When zooming from the wide-angle end to the telephoto end, all lens groups move along the optical axis Z by changing the intervals between adjacent lens groups. The focusing lens group includes the third lens group G3. When focusing from an infinitely distant object to the closest object, the third lens group G3 moves toward the image side, and the other lens groups are fixed relative to the image plane Sim. The anti-vibration group includes lens L21.

[0442] Regarding the variable magnification optical system of Example 13, basic lens data are shown in Table 37, specifications and variable surface intervals are shown in Table 38, aspheric coefficients are shown in Table 39, and various aberration diagrams are shown in Table 30. Fig.28 .

[0443] [Table 37]

[0444] Example 13

[0445]

[0446] [Table 38]

[0447] Example 13

[0448] Wide Middle Tele Zr 1.0 1.4 1.9 f 12.86 18.19 24.44 Bf 13.92 15.61 26.92 FNo. 5.16 5.95 6.87 2ω[°] 106.0 78.0 60.2 DD[6] 17.60 7.54 1.19 DD

[15] 1.19 2.22 3.76 DD

[17] 10.53 12.81 5.62 DD

[19] 13.92 15.61 26.92

[0449] [Table 39]

[0450] Example 13

[0451] Sn 3 4 5 6 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 1.1974923E-04 1.0065031E-04 -6.7253122E-05 -1.0648038E-04 A6 -1.1184244E-06 -5.4455344E-07 -1.3729278E-06 -1.4050329E-06 A8 3.4939609E-09 -2.1617484E-08 1.0758193E-09 1.1420789E-08 A10 0.0000000E+00 3.0446393E-11 -5.7244838E-12 -5.2707175E-11

[0452] Sn 7 8 14 15 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 -2.7876711E-04 -1.8924951E-04 -2.3857464E-05 1.3158512E-04 A6 3.8709538E-08 -3.9396139E-08 4.9126277E-08 1.1534650E-06 A8 -6.4462637E-08 -2.6355724E-08 3.7660767E-08 2.5538765E-08 A10 -1.5535226E-09 -1.7688698E-09 -1.0355652E-09 -5.7863146E-10

[0453] [Example 14]

[0454] The structure and movement trajectory of the variable magnification optical system of Example 14 are shown in FIG. Fig.29. The variable power optical system of Example 14 includes, from the object side to the image side, a first lens group G1 having negative optical power, a second lens group G2 having positive optical power, a third lens group G3 having negative optical power, and a fourth lens group G4 having negative optical power. The subsequent group GR includes two lens groups, namely, the third lens group G3 and the fourth lens group G4. The first lens group G1 includes, from the object side to the image side, three lenses, namely, lenses L11 to L13. The second lens group G2 includes, from the object side to the image side, lens L21, an aperture stop St, and lenses L22 to L26. The third lens group G3 includes one lens, namely, lens L31. The fourth lens group G4 includes one lens, namely, lens L41.

[0455] When zooming from the wide-angle end to the telephoto end, all lens groups move along the optical axis Z by changing the intervals between adjacent lens groups. The focusing lens group includes the third lens group G3. When focusing from an infinitely distant object to the closest object, the third lens group G3 moves toward the image side, and the other lens groups are fixed relative to the image plane Sim. The anti-vibration group includes lens L21.

[0456] Regarding the variable magnification optical system of Example 14, basic lens data is shown in Table 40, specifications and variable surface intervals are shown in Table 41, aspheric coefficients are shown in Table 42, and various aberration diagrams are shown in Table 43. Fig.30 .

[0457] [Table 40]

[0458] Embodiment 14

[0459]

[0460] [Table 41]

[0461] Embodiment 14

[0462] Wide Middle Tele Zr 1.0 1.4 1.9 f 12.21 17.27 23.69 Bf 10.96 13.55 22.61 FNo. 5.16 5.81 6.74 2ω[°] 108.6 79.4 60.4 DD[6] 18.65 7.66 0.96 DD

[17] 1.02 4.25 7.91 DD

[19] 14.16 12.10 4.82 DD

[21] 10.96 13.55 22.61

[0463] [Table 42]

[0464] Embodiment 14

[0465] Sn 3 4 5 6 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 1.4352238E-04 1.8003658E-05 -2.8775269E-04 -2.8073833E-04 A6 -1.2621186E-06 -2.1692614E-07 -1.0412130E-06 -7.8421313E-07 A8 4.3160907E-09 -3.3328091E-08 -1.0930508E-08 1.3066798E-08 A10 0.0000000E+00 3.4281449E-11 1.6329655E-10 -3.8094602E-11

[0466] Sn 7 8 17 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 -2.9330193E-04 -2.1988579E-04 9.0665436E-05 A6 -1.9971326E-06 -1.6966843E-06 9.5780100E-07 A8 -1.6088401E-08 9.3827963E-09 -1.6353750E-08 A10 -3.0850278E-09 -2.5648487E-09 1.9541000E-10

[0467] [Example 15]

[0468] The structure and movement trajectory of the variable magnification optical system of Example 15 are shown in FIG. Fig.31. The variable power optical system of Example 15 includes, from the object side to the image side, a first lens group G1 having negative power, a second lens group G2 having positive power, a third lens group G3 having negative power, and a fourth lens group G4 having negative power. The subsequent group GR includes two lens groups, namely, the third lens group G3 and the fourth lens group G4. The first lens group G1 includes, from the object side to the image side, three lenses, namely, lenses L11 to L13. The second lens group G2 includes, from the object side to the image side, six lenses, namely, an aperture stop St and lenses L21 to L26. The third lens group G3 includes one lens, namely, lens L31. The fourth lens group G4 includes, from the object side to the image side, two lenses, namely, lenses L41 to L42.

[0469] When zooming from the wide-angle end to the telephoto end, all lens groups move along the optical axis Z by changing the intervals between adjacent lens groups. The focusing lens group includes the third lens group G3. When focusing from an infinitely distant object to the closest object, the third lens group G3 moves toward the image side, and the other lens groups are fixed relative to the image plane Sim. The anti-vibration group includes lens L21.

[0470] Regarding the variable magnification optical system of Example 15, basic lens data are shown in Table 43, specifications and variable surface intervals are shown in Table 44, aspheric coefficients are shown in Table 45, and various aberration diagrams are shown in Table 46. Fig.32 .

[0471] [Table 43]

[0472] Embodiment 15

[0473]

[0474] [Table 44]

[0475] Embodiment 15

[0476] Wide Middle Tele Zr 1.0 1.4 1.9 f 12.32 17.42 23.90 Bf 11.01 13.15 18.77 FNo. 5.15 5.78 6.71 2ω[°] 108.4 81.4 62.0 DD[6] 18.70 8.48 2.32 DD

[17] 1.42 1.17 1.64 DD

[19] 8.00 11.09 11.40 DD

[22] 11.01 13.15 18.77

[0477] [Table 45]

[0478] Embodiment 15

[0479]

[0480]

[0481] Sn 8 9 17 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 -9.6088192E-05 -3.2872390E-05 6.2296419E-05 A6 -2.2402146E-07 -6.8967354E-07 5.5167392E-07 A8 7.5748695E-08 1.5022311E-07 -4.9347515E-09 A10 -2.0123997E-09 -5.0288045E-09 1.9541000E-10

[0482] [Example 16]

[0483] The structure and movement trajectory of the variable magnification optical system of Example 16 are shown in FIG. Fig.33. The variable power optical system of Example 16 includes, from the object side to the image side, a first lens group G1 having negative power, a second lens group G2 having positive power, a third lens group G3 having positive power, a fourth lens group G4 having negative power, and a fifth lens group G5 having positive power. The subsequent group GR includes three lens groups, namely, the third lens group G3, the fourth lens group G4, and the fifth lens group G5. The first lens group G1 includes, from the object side to the image side, three lenses, namely, lenses L11 to L13. The second lens group G2 includes, from the object side to the image side, one lens, namely, lens L21. The third lens group G3 includes, from the object side to the image side, five lenses, namely, aperture stop St and lenses L31 to L35. The fourth lens group G4 includes, from the lens L41. The fifth lens group G5 includes, from the lens L51.

[0484] When zooming from the wide-angle end to the telephoto end, all lens groups move along the optical axis Z by changing the intervals between adjacent lens groups. The focusing lens group includes the fourth lens group G4. When focusing from an infinitely distant object to the closest object, the fourth lens group G4 moves toward the image side, and the other lens groups are fixed relative to the image plane Sim. The anti-vibration group includes the second lens group G2.

[0485] Regarding the variable magnification optical system of Example 16, basic lens data are shown in Table 46, specifications and variable surface intervals are shown in Table 47, aspheric coefficients are shown in Table 48, and various aberration diagrams are shown in Table 49. Fig.34 .

[0486] [Table 46]

[0487] Example 16

[0488]

[0489]

[0490] [Table 47]

[0491] Example 16

[0492] Wide Middle Tele Zr 1.0 1.4 1.9 f 12.28 17.37 23.83 Bf 14.97 19.85 17.98 FNo. 4.64 5.33 6.24 2ω[°] 108.6 79.2 60.0 DD[6] 19.52 8.10 0.83 DD[8] 8.63 8.98 7.09 DD

[17] 1.29 2.58 4.66 DD

[19] 6.36 3.56 8.27 DD

[21] 14.97 19.85 17.98

[0493] [Table 48]

[0494] Example 16

[0495] Sn 3 4 5 6 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 1.6777015E-04 1.1992882E-04 -9.3602490E-05 -9.6608503E-05 A6 -2.2957206E-06 -2.1330736E-06 -1.6179738E-06 -1.4574428E-06 A8 1.3277977E-08 -3.1526966E-08 -1.2503161E-08 8.4062370E-09 A10 0.0000000E+00 2.8343686E-10 1.7378989E-10 2.5478204E-13

[0496]

[0497]

[0498] [Example 17]

[0499] The structure and movement trajectory of the variable magnification optical system of Example 17 are shown in FIG. Fig.35 . The variable power optical system of Example 17 includes, from the object side to the image side, a first lens group G1 having negative power, a second lens group G2 having positive power, a third lens group G3 having positive power, a fourth lens group G4 having negative power, and a fifth lens group G5 having positive power. The subsequent group GR includes three lens groups, namely, the third lens group G3, the fourth lens group G4, and the fifth lens group G5. The first lens group G1 includes, from the object side to the image side, three lenses, namely, lenses L11 to L13. The second lens group G2 includes, from the object side to the image side, one lens, namely, lens L21. The third lens group G3 includes, from the object side to the image side, five lenses, namely, aperture stop St and lenses L31 to L35. The fourth lens group G4 includes, from the lens L41. The fifth lens group G5 includes, from the lens L51.

[0500] When zooming from the wide-angle end to the telephoto end, all lens groups move along the optical axis Z by changing the intervals between adjacent lens groups. The focusing lens group includes the fourth lens group G4. When focusing from an infinitely distant object to the closest object, the fourth lens group G4 moves toward the image side, and the other lens groups are fixed relative to the image plane Sim. The anti-vibration group includes the second lens group G2.

[0501] Regarding the variable magnification optical system of Example 17, basic lens data is shown in Table 49, specifications and variable surface intervals are shown in Table 50, aspheric coefficients are shown in Table 51, and various aberration diagrams are shown in Table 52. Fig.36 .

[0502] [Table 49]

[0503] Embodiment 17

[0504]

[0505]

[0506] [Table 50]

[0507] Embodiment 17

[0508] Wide Middle Tele Zr 1.0 1.4 2.1 f 12.22 17.29 25.67 Bf 16.19 18.06 22.50 FNo. 5.16 5.81 7.07 2ω[°] 108.6 79.4 57.2 DD[6] 19.91 8.93 1.88 DD[8] 4.92 3.28 0.24 DD

[17] 0.83 2.00 2.79 DD

[19] 6.94 8.36 11.68 DD

[21] 16.19 18.06 22.50

[0509] [Table 51]

[0510] Embodiment 17

[0511] Sn 3 4 5 6 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 2.4217097E-04 1.5532071E-04 -2.3248836E-04 -2.3986047E-04 A6 -1.2216001E-06 6.0333283E-07 -7.6012719E-08 -3.1843532E-07 A8 3.1880085E-09 -1.8864786E-08 -7.4608966E-09 5.6916655E-09 A10 0.0000000E+00 1.9453327E-11 5.2900039E-11 -1.3581954E-11

[0512] Sn 7 8 17 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 -4.1515322E-04 -2.5106257E-04 1.2726560E-04 A6 -6.2834472E-06 -3.9302514E-06 8.4938501E-07 A8 3.5115942E-08 2.9342254E-08 -4.6135685E-09 A10 -8.4925832E-09 -4.6394777E-09 1.9541000E-10

[0513] [Example 18]

[0514] The structure and movement trajectory of the variable magnification optical system of Example 18 are shown in FIG. Fig.37 . The variable power optical system of Example 18 includes, from the object side to the image side, a first lens group G1 having negative power, a second lens group G2 having positive power, a third lens group G3 having positive power, a fourth lens group G4 having negative power, and a fifth lens group G5 having negative power. The subsequent group GR includes three lens groups, namely, the third lens group G3, the fourth lens group G4, and the fifth lens group G5. The first lens group G1 includes, from the object side to the image side, four lenses, namely, lenses L11 to L14. The second lens group G2 includes, from the object side to the image side, one lens, namely, lens L21. The third lens group G3 includes, from the object side to the image side, five lenses, namely, aperture stop St and lenses L31 to L35. The fourth lens group G4 includes, from the lens L41, one lens. The fifth lens group G5 includes, from the lens L51, one lens.

[0515] When zooming from the wide-angle end to the telephoto end, all lens groups move along the optical axis Z by changing the intervals between adjacent lens groups. The focusing lens group includes the fourth lens group G4. When focusing from an infinitely distant object to the closest object, the fourth lens group G4 moves toward the image side, and the other lens groups are fixed relative to the image plane Sim. The anti-vibration group includes the second lens group G2.

[0516] Regarding the variable magnification optical system of Example 18, basic lens data are shown in Table 52, specifications and variable surface intervals are shown in Table 53, aspheric coefficients are shown in Table 54, and various aberration diagrams are shown in Table 55. Fig.38 .

[0517] [Table 52]

[0518] Embodiment 18

[0519]

[0520] [Table 53]

[0521] Embodiment 18

[0522] Wide Middle Tele Zr 1.0 1.4 2.1 f 12.26 17.34 25.74 Bf 12.91 20.92 30.11 FNo. 5.15 5.84 7.06 2ω[°] 108.4 81.2 58.0 DD[8] 17.55 8.11 1.78 DD

[10] 4.17 2.95 0.01 DD

[19] 0.08 1.04 1.76 DD

[21] 11.54 7.45 5.84 DD

[23] 12.91 20.92 30.11

[0523] [Table 54]

[0524] Embodiment 18

[0525] Sn 5 6 7 8 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 1.7672566E-04 7.0721380E-05 -2.3354429E-04 -2.2587478E-04 A6 -1.3524715E-06 2.3166618E-07 -1.0335805E-07 -4.8332442E-07 A8 2.6415974E-09 -2.0733995E-08 -8.4848505E-09 8.7439855E-09 A10 0.0000000E+00 -7.7103234E-11 6.0438959E-11 -2.1374773E-12

[0526] Sn 9 10 19 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 -3.8825691E-04 -2.2515159E-04 1.2915608E-04 A6 -4.8832035E-06 -3.6869311E-06 7.4747940E-07 A8 -3.5311225E-08 2.5756266E-08 -4.5460297E-09 A10 -5.5641473E-09 -3.8154995E-09 1.9541000E-10

[0527] [Example 19]

[0528] The structure and movement trajectory of the variable magnification optical system of Example 19 are shown in FIG. Fig.39. The variable power optical system of Example 19 includes, from the object side to the image side, a first lens group G1 having negative power, a second lens group G2 having positive power, a third lens group G3 having negative power, a fourth lens group G4 having positive power, and a fifth lens group G5 having positive power. The subsequent group GR includes three lens groups, namely, the third lens group G3, the fourth lens group G4, and the fifth lens group G5. The first lens group G1 includes, from the object side to the image side, three lenses, namely, lenses L11 to L13. The second lens group G2 includes, from the object side to the image side, lens L21, an aperture stop St, and lenses L22 to L24. The third lens group G3 includes one lens, namely, lens L31. The fourth lens group G4 includes one lens, namely, lens L41. The fifth lens group G5 includes one lens, namely, lens L51.

[0529] When zooming from the wide-angle end to the telephoto end, the fifth lens group G5 is fixed relative to the image plane Sim, and the other lens groups move along the optical axis Z by changing the intervals between adjacent lens groups. The focusing lens group includes the third lens group G3. When focusing from an infinitely distant object to the closest object, the third lens group G3 moves toward the image side, and the other lens groups are fixed relative to the image plane Sim. The anti-vibration group includes lens L21.

[0530] Regarding the variable magnification optical system of Example 19, basic lens data are shown in Table 55, specifications and variable surface intervals are shown in Table 56, aspheric coefficients are shown in Table 57, and various aberration diagrams are shown in Table 58. Fig.40 .

[0531] [Table 55]

[0532] Embodiment 19

[0533]

[0534] [Table 56]

[0535] Embodiment 19

[0536]

[0537]

[0538] [Table 57]

[0539] Embodiment 19

[0540] Sn 5 6 13 14 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 -3.3614432E-05 -4.7555765E-05 -1.1374329E-04 4.8118646E-05 A6 5.4657374E-10 2.5790496E-07 -1.9066192E-06 -2.2282568E-06 A8 1.1519429E-09 -1.6590025E-09 1.2682754E-07 1.1011527E-07 A10 -1.4673234E-11 -4.2867523E-12 -4.3172848E-09 -3.2591354E-09

[0541]

[0542] [Example 20]

[0543] The structure and movement trajectory of the variable magnification optical system of Example 20 are shown in FIG. Fig.41 . The variable power optical system of Example 20 includes, from the object side to the image side, a first lens group G1 having negative power, a second lens group G2 having positive power, a third lens group G3 having negative power, a fourth lens group G4 having negative power, and a fifth lens group G5 having positive power. The subsequent group GR includes three lens groups, namely, the third lens group G3, the fourth lens group G4, and the fifth lens group G5. The first lens group G1 includes, from the object side to the image side, three lenses, namely, lenses L11 to L13. The second lens group G2 includes, from the object side to the image side, lens L21, an aperture stop St, and lenses L22 to L24. The third lens group G3 includes one lens, namely, lens L31. The fourth lens group G4 includes one lens, namely, lens L41. The fifth lens group G5 includes one lens, namely, lens L51.

[0544] When zooming from the wide-angle end to the telephoto end, all lens groups move along the optical axis Z by changing the intervals between adjacent lens groups. The focusing lens group includes the third lens group G3. When focusing from an infinitely distant object to the closest object, the third lens group G3 moves toward the image side, and the other lens groups are fixed relative to the image plane Sim. The anti-vibration group includes lens L21.

[0545] Regarding the variable magnification optical system of Example 20, basic lens data is shown in Table 58, specifications and variable surface intervals are shown in Table 59, aspheric coefficients are shown in Table 60, and various aberration diagrams are shown in Table 61. Fig.42 .

[0546] [Table 58]

[0547] Embodiment 20

[0548]

[0549] [Table 59]

[0550] Embodiment 20

[0551] Wide Middle Tele Zr 1.0 1.5 2.2 f 13.23 19.62 29.10 Bf 10.36 15.36 34.66 FNo. 5.10 6.29 7.51 2ω[°] 103.4 74.8 52.0 DD[6] 27.02 16.79 6.80 DD

[14] 0.05 0.09 0.25 DD

[16] 4.97 3.82 1.78 DD

[18] 7.45 12.08 2.08 DD

[20] 10.36 15.36 34.66

[0552] [Table 60]

[0553] Embodiment 20

[0554]

[0555]

[0556]

[0557] The corresponding values ​​of conditional expressions (1) to (3) and (5) to (33) of the variable power optical systems of Examples 1 to 20 are shown in Tables 61 to 64. The corresponding values ​​of the Examples shown in Tables 61 to 64 can be used as the upper limit or lower limit of the conditional expressions to set the preferred range of the conditional expressions. In addition, as described above, the corresponding values ​​of conditional expression (4) of the lenses of the first lens group G1 are shown in the column "NG1L+0.01×v G1L" of the basic lens data, so the description is omitted in Tables 61 to 64.

[0558] [Table 61]

[0559]

[0560]

[0561] [Table 62]

[0562] Type No. Example 6 Example 7 Example 8 Example 9 Example 10 (1) TLw / (ft×tanωt) 7.5144 6.2863 7.7761 6.1344 6.6756 (2) Bfw / (ft×tanωt) 1.2959 1.3344 1.3242 1.8206 1.3989 (3) <![CDATA[(fw×TLw) / ft 2 ]]> 1.7937 1.3751 1.5843 1.5922 2.0032 (5) Dsum / (TLw-Bfw) 0.3681 0.4294 0.3676 0.5611 0.5762 (6) dG1 / |f1| 0.9567 0.9805 1.0020 1.0333 1.1609 (7) NG1n+0.01×v G1n 2.1047 2.1047 2.1047 2.1047 2.0928 (8) dm / dG1 0.2660 0.2892 0.5235 0.2978 0.2550 (9) f2 / |f1| 1.5015 1.4460 1.4945 2.3603 1.1396 (10) fw / |f1| 0.6854 0.6935 0.7332 0.7632 0.8123 (11) (Rf+Rr) / (Rf-Rr) 2.8954 3.3002 1.5299 1.6444 2.1302 (12) ft / |fois| 1.0040 1.1028 1.1279 1.6793 0.6642 (13) ft / |ffoc| 0.6633 0.8221 0.6917 1.4103 1.1326 (14) Nr+0.01×vr 2.1047 2.1047 2.1047 - - (15) ft / |f1| 1.5076 1.5947 1.6857 1.6033 1.5190 (16) <![CDATA[|f1| / (fw×ft) 1 / 2 ]]> 0.9837 0.9509 0.8995 0.9040 0.9003 (17) <![CDATA[f2 / (fw×ft) 1 / 2 ]]> 1.4771 1.3750 1.3443 2.1338 1.0260 (18) dG1 / (TLw-Bfw) 0.1944 0.2469 0.1967 0.2740 0.2581 (19) |f1| / (ft / FNot) 4.6166 4.1576 4.4076 4.3412 4.3712 (20) fw / |ffoc 0.3016 0.3575 0.3008 0.6714 0.6056 (21) N1nm 1.6516 1.6516 1.7550 1.4875 1.4875 (22) NG1n 1.5444 1.5444 1.5444 1.5444 1.5341 (23) Dfoc / (ft×tanωt) 0.2442 0.3052 0.1979 0.0315 0.0367 (24) v foc 94.66 - 94.66 50.31 40.78 (25) ω 55.5 55.8 55 54.3 52.6 (26) ft / fw 2.2 2.3 2.3 2.1 1.9 (27) ρL1n 3.06 3.06 1.04 1.04 1.01 (28) dL1nh / dL1n - - 2.80229 3.18721 3.82753 (29) ρL2nm 1.04 1.04 - - - (30) dL2nmh / dL2nm 1.9353 1.2343 - - - (31) fw / |fL1nm| 0.2465 0.2217 0.6060 0.3574 0.3157 (32) ρLr 1.04 1.04 1.04 - - (33) dL1nmh / dL1nm 5.7972 5.6214 6.9170 7.8984 6.2766

[0563] [Table 63]

[0564] Type No. Embodiment 11 Example 12 Example 13 Embodiment 14 Embodiment 15 (1) TLw / (ft×tanωt) 5.9940 5.9046 5.8567 6.2995 5.9438 (2) Bfw / (ft×tanωt) 1.3644 1.2380 0.9825 0.7949 0.7667 (3) <![CDATA[(fw×TLw) / ft 2 ]]> 1.8060 1.3254 1.7864 1.8897 1.8410 (5) Dsum / (TLw-Bfw) 0.6141 0.6320 0.5754 0.5543 0.6218 (6) dG1 / |f1| 1.1499 1.2048 1.0158 1.2875 0.9011 (7) NG1n+0.01×v G1n 2.0928 2.0928 2.0928 2.1047 2.0928 (8) dm / dG1 0.2966 0.3089 0.3128 0.3351 0.2978 (9) f2 / |f1| 1.0932 1.2489 1.0091 1.3053 1.0181 (10) fw / |f1| 0.8750 0.9619 0.7774 0.8865 0.6900 (11) (Rf+Rr) / (Rf-Rr) 1.5904 1.5242 1.8334 1.9906 1.3879 (12) ft / |fois| 0.7482 0.8611 0.5410 0.7288 0.6735 (13) ft / |ffoc| 1.5202 2.5309 0.8720 0.7481 0.4041 (14) Nr+0.01×vr - - - - - (15) ft / |f1| 1.6970 2.2118 1.4774 1.7200 1.3385 (16) <![CDATA[|f1| / (f W ×ft) 1 / 2 ]]> 0.8206 0.6856 0.9331 0.8099 1.0406 (17) <![CDATA[f2 / (f W ×ft) 1 / 2 ]]> 0.8971 0.8562 0.9416 1.0571 1.0595 (18) <![CDATA[dG1 / (TL W -Bf W )]]> 0.2505 0.2262 0.2434 0.2337 0.2164 (19) |f1| / (ft / FNot) 4.0836 3.0564 4.6500 3.9187 5.0132 (20) fw / |ffoc| 0.7839 1.1007 0.4588 0.3856 0.2083 (21) N1nm 1.4875 1.4875 1.4875 1.4875 1.4875 (22) NG1n 1.5341 1.5341 1.5341 1.5444 1.5341 (23) Dfoc / (ft×tanωt) 0.0356 0.0316 0.0346 0.0337 0.0382 (24) v foc 50.31 29.14 50.31 50.31 52.32 (25) ω 543 53.8 53 54.3 54.2 (26) ft / fw 1.9 2.3 1.9 1.9 1.9 (27) ρL1n 1.01 1.01 1.01 1.04 1.01 (28) dL1nh / dL1n 3.42962 3.73911 3.86018 3.18201 3.46205 (29) ρL2nm - - - - - (30) dL2nmh / dL2nm - - - - - (31) fw / |fL1nm| 0.3648 0.3788 0.3504 0.3102 0.4000 (32) ρLr - - - - - (33) dL 1nmh / dL 1nm 6.3683 6.6903 6.5016 4.4810 6.5890

[0565] [Table 64]

[0566] Type No. Example 16 Embodiment 17 Embodiment 18 Embodiment 19 Embodiment 20 (1) TLw / (ft×tanωt) 5.9724 5.9994 5.9701 6.8818 5.7906 (2) Bfw / (ft×tanωt) 1.0881 1.1568 0.9048 0.8042 0.7299 (3) <![CDATA[(fw×TLw) / ft 2 ]]> 1.7769 1.5571 1.5762 1.3603 1.2840 (5) Dsum / (TLw-Bfw) 0.4673 0.5190 0.5387 0.4588 0.4502 (6) dG1 / |f1| 1.0417 1.0113 1.3839 0.7366 0.6504 (7) N61n+0.01×v G1n 2.0928 2.1047 2.1047 2.2693 2.2370 (8) dm / dG1 0.2117 0.2979 0.2961 0.4537 0.4839 (9) f2 / |f1| 2.2120 2.0443 2.3159 0.7262 0.4961 (10) fw / |f1| 0.8158 0.7458 0.8592 0.6378 0.6222 (11) (Rf+Rr) / (Rf-Rr) 1.2620 1.6216 1.1783 2.3907 2.6033 (12) ft / |fois| 0.7157 0.7664 0.7789 1.0565 0.8317 (13) ft / |ffoc| 1.8095 1.4225 1.4728 2.1134 2.1148 (14) Nr+0.01×vr - - - - - (15) ft / |f1| 1.5832 1.5667 1.8038 1.4031 1.3686 (16) <![CDATA[|f1| / (fw×ft) 1 / 2 ]]> 0.8799 0.9251 0.8033 1.0571 1.0837 (17) <![CDATA[f2 / (fw×ft) 1 / 2 ]]> 1.9463 1.8912 1.8603 0.7677 0.5377 (18) dG1 / (TLw-Bfw) 0.2333 0.2445 0.2733 0.1987 0.1925 (19) |f1| / (ft / FNot) 3.9414 4.5127 3.9139 4.0269 5.4875 (20) fw / |ffoc 0.9325 0.6772 0.7015 0.9608 0.9615 (21) N1nm 1.4875 1.4875 1.5168 1.7754 1.7754 (22) N61n 1.5341 1.5444 1.5444 1.8040 1.6516 (23) Dfoc / (ft×tanωt) 0.0322 0.0340 0.0304 0.0966 0.0617 (24) v foc 50.31 50.31 50.31 52.32 60.08 (25) ω 54.3 54.3 54.2 51.1 51.7 (26) ft / fw 1.9 2.1 2.1 2.2 2.2 (27) ρ L1n 1.01 1.04 1.04 4.46 3.24 (28) dL1nh / dL1n 4.10934 3.00672 3.05394 - - (29) ρL2nm - - - - - (30) dL2nmh / dL2nm - - - - - (31) fw / |fL1nm| 0.4220 0.3606 0.4643 0.4496 0.3889 (32) ρLr - - - 1.23 1.04 (33) dL1nmh / dL1nm 6.7013 7.9166 7.1314 3.2727 5.5481

[0567] Although the variable power optical systems of Examples 1 to 20 are configured to be compact and lightweight, various aberrations are well corrected throughout the entire variable power range, thereby maintaining high optical performance.

[0568] Next, an imaging device according to an embodiment of the present invention will be described. Fig.43 and Fig.44 2 shows an external view of a camera 30 as an imaging device according to an embodiment of the present invention. Fig.43 1 is a perspective view showing the camera 30 as viewed from the front side. Fig.44 The camera 30 is a perspective view viewed from the back. The camera 30 is a so-called mirrorless digital camera, and can detachably mount an interchangeable lens 20. The interchangeable lens 20 includes the variable power optical system 1 according to one embodiment of the present invention housed in a lens barrel.

[0569] The camera 30 includes a camera body 31. A shutter button 32 and a power button 33 are provided on the upper surface of the camera body 31. An operation unit 34, an operation unit 35 and a display unit 36 ​​are provided on the back surface of the camera body 31. The display unit 36 ​​can display the captured image and the image existing in the angle of view before the capture.

[0570] An imaging opening through which light from a photographic subject enters is provided at the center of the front surface of the camera body 31 . A bayonet mount 37 is provided at a position corresponding to the imaging opening, and the interchangeable lens 20 is mounted on the camera body 31 via the bayonet mount 37 .

[0571] An imaging element 38 is provided in the camera body 31. The imaging element 38 outputs an imaging signal corresponding to the subject image formed by the interchangeable lens 20. As the imaging element 38, for example, a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor) can be used. A signal processing circuit (not shown) and a recording medium (not shown) are provided in the camera body 31. The signal processing circuit processes the imaging signal output from the imaging element 38 to generate an image. The recording medium is used to record the generated image. In the camera 30, a still image or a moving image can be captured by pressing the shutter button 32, and the image data obtained by the capturing is recorded in the above-mentioned recording medium.

[0572] The above embodiments and examples are used to illustrate the technology of the present invention, but the technology of the present invention 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 and aspheric coefficient of each lens are not limited to the values ​​shown in the above embodiments, and other values ​​can be used.

[0573] Furthermore, the imaging device according to the embodiment of the present invention is not limited to the above-mentioned example, and can be variously configured as a camera other than a mirrorless camera, a film camera, a video camera, a security camera, and the like.

[0574] The following supplementary notes are further disclosed with respect to the above-mentioned embodiments and examples.

[0575] [Note 1]

[0576] A variable magnification optical system, which comprises, from the object side to the image side, a first lens group with negative optical power, a second lens group with positive optical power, and a subsequent group including one or more lens groups,

[0577] When changing the magnification, the first lens group moves, and all the intervals between adjacent lens groups change.

[0578] One of the lens groups included in the subsequent group is a focus lens group that moves along the optical axis when focusing,

[0579] When the sum of the distance on the optical axis from the lens surface closest to the object side of the first lens group to the lens surface closest to the image side of the subsequent lens group in a state of focusing on an infinitely distant object at the wide angle end and the back focus of the entire system in terms of air conversion distance is denoted as TLw,

[0580] Let the focal length of the entire system when focusing on an infinitely distant object at the telephoto end be ft,

[0581] The maximum half angle of view when focusing on an infinitely distant object at the telephoto end is set to ωt,

[0582] The back focal length of the entire system in terms of air conversion distance when focusing on an infinitely far object at the wide angle end is Bfw.

[0583] Let fw be the focal length of the entire system when focusing on an infinitely far object at the wide angle end.

[0584] The refractive index of any lens included in the first lens group with respect to the d-line and the Abbe number based on the d-line are NG1L and v G1L, respectively.

[0585] When the sum of the thicknesses on the optical axis of all lens groups is defined as Dsum, the following conditional expressions (1), (2), (3), (4), and (5) are satisfied:

[0586] 4.5<TLw / (ft×tanωt)<8 (1);

[0587] 0.4<Bfw / (ft×tanωt)<3 (2);

[0588] 0.9<(fw×TLw) / ft 2 <3.2 (3);

[0589] 1.6<NG1L+0.01×v G1L<2.3 (4);

[0590] 0.1<Dsum / (TLw-Bfw)<0.8 (5).

[0591] [Note 2]

[0592] According to the variable magnification optical system described in Supplementary Note 1, it satisfies the following conditional expression (1-1):

[0593] 5.4<TLw / (ft×tanωt)<7 (1-1).

[0594] [Note 3]

[0595] According to Supplement 1 or Supplement 2, the variable magnification optical system satisfies the following conditional expression (2-1):

[0596] 0.55<Bfw / (ft×tanωt)<2 (2-1).

[0597] [Note 4]

[0598] According to any one of Supplementary Notes 1 to 3, the variable magnification optical system satisfies the following conditional expression (4-1):

[0599] 1.82<NG1L+0.01×v G1L<1.91 (4-1).

[0600] [Note 5]

[0601] A variable magnification optical system according to any one of Supplement 1 to Supplement 4, wherein:

[0602] When the thickness of the first lens group on the optical axis is dG1,

[0603] When the focal length of the first lens group is set to f1, the following conditional expression (6) is satisfied:

[0604] 0.4<dG1 / |f1|<2 (6).

[0605] [Note 6]

[0606] According to the variable magnification optical system described in Supplementary Note 5, it satisfies the following conditional expression (6-1):

[0607] 0.55<dG1 / |f1|<1.65 (6-1).

[0608] [Note 7]

[0609] According to the variable magnification optical system described in Supplementary Note 5, it satisfies the following conditional expression (6-2):

[0610] 0.75<dG1 / |f1|<1.35 (6-2).

[0611] [Note 8]

[0612] A variable magnification optical system according to any one of Supplementary Notes 1 to 7, wherein:

[0613] The first lens group includes an L1nm lens as a negative meniscus lens with a convex surface facing the uncemented object side, an L1n lens as a negative lens with a concave surface facing the uncemented image side, and an L1p lens as a positive lens.

[0614] The L1n lens is arranged at a position adjacent to the image side of the L1nm lens.

[0615] The L1p lens is arranged on the image side with respect to the L1n lens.

[0616] [Note 9]

[0617] The variable magnification optical system according to Supplementary Note 8 includes a negative lens, wherein:

[0618] When the refractive index of the negative lens disposed between the L1nm lens and the L1p lens with respect to the d-line and the Abbe number based on the d-line are NG1n and vG1n, respectively, the negative lens satisfies the following conditional expression (7):

[0619] 1.7<NG1n+0.01×v G1n<2.16 (7),

[0620] The negative lens satisfying the conditional expression (7) is the L1n lens or a negative lens disposed adjacent to the image side of the L1n lens.

[0621] [Note 10]

[0622] The variable magnification optical system according to Supplement 9, wherein:

[0623] The negative lens satisfying the conditional expression (7) satisfies the following conditional expression (7-1):

[0624] 1.74<NGln+0.01×v G1n<2.14 (7-1).

[0625] [Note 11]

[0626] A variable magnification optical system according to any one of Supplementary Notes 8 to 10, wherein:

[0627] When the distance on the optical axis between the L1nm lens and the L1n lens is set to dm,

[0628] When the thickness of the first lens group on the optical axis is set to dG1, the following conditional expression (8) is satisfied:

[0629] 0.01<dm / dG1<0.9 (8).

[0630] [Note 12]

[0631] A variable magnification optical system according to any one of Supplementary Notes 8 to 11, wherein:

[0632] The object-side surface of the L1n lens is an aspherical surface whose refractive power at the position of the maximum effective diameter is shifted in the positive direction compared with the refractive power in the paraxial region.

[0633] [Note 13]

[0634] The variable magnification optical system according to Supplement 12, wherein:

[0635] The object-side surface of the L1n lens is concave in the paraxial region and is convex in the peripheral portion including the position of the maximum effective diameter.

[0636] [Note 14]

[0637] A variable magnification optical system according to any one of Supplement 1 to Supplement 13, wherein:

[0638] When the focal length of the second lens group is set to f2,

[0639] When the focal length of the first lens group is set to f1, the following conditional expression (9) is satisfied:

[0640] 0.3<f2 / |f1|<5 (9).

[0641] [Note 15]

[0642] According to the variable power optical system described in Supplementary Note 14, it satisfies the following conditional expression (9-1):

[0643] 0.65<f2 / |f1|<3 (9-1).

[0644] [Note 16]

[0645] A variable magnification optical system according to any one of Supplement 1 to Supplement 15, wherein:

[0646] The first lens group includes a positive lens whose convex surface faces the object side, on the side closest to the object.

[0647] [Note 17]

[0648] A variable magnification optical system according to any one of Supplementary Notes 1 to 16, wherein:

[0649] The first lens group includes four or less lenses.

[0650] [Note 18]

[0651] A variable magnification optical system according to any one of Supplement 1 to Supplement 17, wherein:

[0652] When the focal length of the first lens group is set to f1, the following conditional expression (10) is satisfied:

[0653] 0.45<fw / |f1|<2 (10).

[0654] [Note 19]

[0655] A variable magnification optical system according to any one of Supplementary Notes 1 to 18, wherein:

[0656] The first lens group includes an L1nm lens which is a negative meniscus lens with a convex surface facing the unjoined object side.

[0657] When the paraxial curvature radius of the object-side surface of the L1nm lens is set to Rf,

[0658] When the paraxial curvature radius of the image-side surface of the L1nm lens is set to Rr, the following conditional expression (11) is satisfied:

[0659] 1<(Rf+Rr) / (Rf-Rr)<7 (11).

[0660] [Note 20]

[0661] A variable magnification optical system according to any one of Supplement 1 to Supplement 19, wherein:

[0662] An anti-vibration group is arranged at a position closer to the image side than the first lens group, and moves in a direction intersecting the optical axis during image shake correction.

[0663] When the focal length of the anti-vibration group is set to fois, the following conditional expression (12) is satisfied:

[0664] 0.3<ft / |fois|<4 (12).

[0665] [Note 21]

[0666] A variable magnification optical system according to any one of Supplementary Notes 1 to 20, wherein:

[0667] When the focal length of the focusing lens group is set to ffoc, the following conditional expression (13) is satisfied:

[0668] 0.3<ft / |ffoc|<3 (13).

[0669] [Note 22]

[0670] A variable magnification optical system according to any one of Supplement 1 to Supplement 21, wherein:

[0671] An Lr lens is arranged on the image side of the focus lens group.

[0672] When the refractive index of the Lr lens with respect to the d-line and the Abbe number based on the d-line are respectively set to Nr and vr, the following conditional expression (14) is satisfied:

[0673] 1.7<Nr+0.01×vr<2.16 (14).

[0674] [Note 23]

[0675] An imaging device comprising the variable magnification optical system according to any one of Supplementary Notes 1 to 22.

Claims

1. A variable power optical system, comprising, from the object side to the image side, a first lens group having negative power, a second lens group having positive power, and a subsequent group including one or more lens groups, When changing the magnification, the first lens group moves, and all the intervals between adjacent lens groups change. One of the lens groups included in the subsequent group is a focus lens group that moves along the optical axis when focusing, When the sum of the distance on the optical axis from the lens surface closest to the object side of the first lens group to the lens surface closest to the image side of the subsequent lens group in a state of focusing on an infinitely distant object at the wide angle end and the back focus of the entire system in terms of air conversion distance is denoted as TLw, Let the focal length of the entire system when focusing on an infinitely distant object at the telephoto end be ft, The maximum half angle of view when focusing on an infinitely distant object at the telephoto end is set to ωt, The back focal length of the entire system in terms of air conversion distance when focusing on an infinitely far object at the wide angle end is Bfw. Let fw be the focal length of the entire system when focusing on an infinitely far object at the wide angle end. The refractive index of any lens included in the first lens group with respect to the d-line and the Abbe number based on the d-line are NG1L and vG1L, respectively. When the sum of the thicknesses on the optical axis of all lens groups is defined as Dsum, the following conditional expressions (1), (2), (3), (4), and (5) are satisfied: 4.5 <TLw / (ft×tanωt)<8 (1); 0.4 <Bfw / (ft×tanωt)<3 (2); 0.9<(fw×TLw) / ft 2 <3.2 (3); 1.6 <NG1L+0.01×vG1L<2.3 (4); 0.1<Dsum / (TLw-Bfw)<0.8 (5).

2. The variable magnification optical system according to claim 1, which satisfies the following conditional expression (1-1): 5.4 <TLw / (ft×tanωt)<7 (1-1)。 3. The variable magnification optical system according to claim 1 or 2, which satisfies the following conditional expression (2-1): 0.55 <Bfw / (ft×tanωt)<2 (2-1)。 4. The variable magnification optical system according to claim 1 or 2, wherein: When the thickness of the first lens group on the optical axis is dG1, When the focal length of the first lens group is set to f1, the following conditional expression (6) is satisfied: 0.4 <dG1 / |f1|<2 (6)。 5. The variable magnification optical system according to claim 4, which satisfies the following conditional expression (6-1): 0.55 <dG1 / |f1|<1.65 (6-1)。 6. The variable magnification optical system according to claim 1 or 2, wherein: The first lens group includes an L1nm lens as a negative meniscus lens with a convex surface facing the uncemented object side, an L1n lens as a negative lens with a concave surface facing the uncemented image side, and an L1p lens as a positive lens. The L1n lens is arranged at a position adjacent to the image side of the L1nm lens. The L1p lens is arranged on the image side with respect to the L1n lens.

7. The variable power optical system according to claim 6, comprising a negative lens, wherein: When the refractive index of the negative lens disposed between the L1nm lens and the L1p lens with respect to the d-line and the Abbe number based on the d-line are NG1n and vG1n, respectively, the negative lens satisfies the following conditional expression (7): 1.7 <NGln+0.01×vG1n<2.16 (7), The negative lens satisfying the conditional expression (7) is the L1n lens or a negative lens disposed adjacent to the image side of the L1n lens.

8. The variable magnification optical system according to claim 7, wherein: The negative lens satisfying the conditional expression (7) satisfies the following conditional expression (7-1): 1.74<NG1n+0.01×vG1n<2.14 (7-1).

9. The variable magnification optical system according to claim 6, wherein: When the distance on the optical axis between the L1nm lens and the L1n lens is set to dm, When the thickness of the first lens group on the optical axis is set to dG1, the following conditional expression (8) is satisfied: 0.01 <dm / dG1<0.9 (8)。 10. The variable power optical system according to claim 6, wherein: The object-side surface of the L1n lens is an aspherical surface whose refractive power at the position of the maximum effective diameter is shifted in the positive direction compared with the refractive power in the paraxial region.

11. The variable power optical system according to claim 10, wherein: The object-side surface of the L1n lens is concave in the paraxial region and is convex in the peripheral portion including the position of the maximum effective diameter.

12. The variable magnification optical system according to claim 1 or 2, wherein: When the focal length of the second lens group is set to f2, When the focal length of the first lens group is set to f1, the following conditional expression (9) is satisfied: 0.3 <f2 / |f1|<5 (9)。 13. The variable magnification optical system according to claim 12, which satisfies the following conditional expression (9-1): 0.65 <f2 / |f1|<3 (9-1)。 14. The variable magnification optical system according to claim 13, which satisfies the following conditional expression (1-1): 5.4<TLw / (ft×tanωt)<7 (1-1).

15. The variable power optical system according to claim 14, wherein: The first lens group includes an L1nm lens as a negative meniscus lens with a convex surface facing the uncemented object side, an L1n lens as a negative lens with a concave surface facing the uncemented image side, and an L1p lens as a positive lens. The L1n lens is arranged at a position adjacent to the image side of the L1nm lens. The L1p lens is arranged on the image side with respect to the L1n lens.

16. The variable power optical system according to claim 15, comprising a negative lens, wherein: When the refractive index of the negative lens disposed between the L1nm lens and the L1p lens with respect to the d-line and the Abbe number based on the d-line are NG1n and vG1n, respectively, the negative lens satisfies the following conditional expression (7-1): 1.74<NG1n+0.01×vG1n<2.14 (7-1), The negative lens satisfying the conditional expression (7-1) is the L1n lens or a negative lens arranged adjacent to the image side of the L1n lens.

17. The variable power optical system according to claim 16, wherein: The first lens group includes a positive lens whose convex surface faces the object side, on the side closest to the object.

18. The variable magnification optical system according to claim 16, which satisfies the following conditional expression (4-1): 1.82 <NG1L+0.01×v G1L<1.91(4-1)。 19. The variable power optical system according to claim 16, wherein: When the thickness of the first lens group on the optical axis is set to dG1, the following conditional expression (6-1) is satisfied: 0.55<dG1 / |f1|<1.65 (6-1).

20. The variable power optical system according to claim 19, which satisfies the following conditional expression (6-2): 0.75<dG1 / |f1|<1.35 (6-2).

21. The variable power optical system according to claim 19, wherein: When the distance on the optical axis between the L1nm lens and the L1n lens is set to dm, the following conditional expression (8) is satisfied: 0.01 <dm / dG1<0.9 (8)。 22. The variable power optical system according to claim 19, wherein: The first lens group includes four or less lenses.

23. The variable power optical system according to claim 19, wherein: The object-side surface of the L1n lens is an aspherical surface whose refractive power at the position of the maximum effective diameter is shifted in the positive direction compared with the refractive power in the paraxial region.

24. The variable power optical system according to claim 1 or 2, wherein: When the focal length of the first lens group is set to f1, the following conditional expression (10) is satisfied: 0.45 <fw / |f1|<2 (10)。 25. The variable magnification optical system according to claim 1 or 2, wherein: The first lens group includes an L1nm lens which is a negative meniscus lens with a convex surface facing the unjoined object side. When the paraxial curvature radius of the object-side surface of the L1nm lens is set to Rf, When the paraxial curvature radius of the image-side surface of the L1nm lens is set to Rr, the following conditional expression (11) is satisfied: 1<(Rf+Rr) / (Rf-Rr)<7 (11).

26. The variable magnification optical system according to claim 1 or 2, wherein: An anti-vibration group is arranged at a position closer to the image side than the first lens group, and moves in a direction intersecting the optical axis during image shake correction. When the focal length of the anti-vibration group is set to fois, the following conditional expression (12) is satisfied: 0.3 <ft / |fois|<4 (12)。 27. The variable magnification optical system according to claim 1 or 2, wherein: When the focal length of the focusing lens group is set to ffoc, the following conditional expression (13) is satisfied: 0.3 <ft / |ffoc|<3 (13)。 28. The variable power optical system according to claim 1 or 2, wherein: An Lr lens is arranged at a position closer to the image side than the focus lens group. When the refractive index of the Lr lens with respect to the d-line and the Abbe number based on the d-line are respectively set to Nr and vr, the following conditional expression (14) is satisfied: 1.7 <Nr+0.01×vr<2.16 (14)。 29. An imaging device comprising the variable power optical system according to any one of claims 1 to 28.

Images