Imaging lens and imaging device

Abstract

The imaging lens includes, in order from an object side, a front group, an aperture, and a rear group. The front group includes a first lens as a negative lens having a concave surface facing the image side, and a second lens as a negative lens having a concave surface facing the image side, the first lens and the second lens being consecutively arranged in order from the most object side. Two or less focus lens groups are disposed closer to the image side than the second lens. During focusing, the two or less focus lens groups move along the optical axis, and lenses other than the two or less focus lens groups are fixed with respect to the image plane. The imaging lens satisfies a preset conditional expression.

Description

Technical Field

[0001] The technology of the present invention relates to an imaging lens and a photographing device. Background Art

[0002] Conventionally, as an imaging lens that can be used in a photographing device such as a digital camera, imaging lenses described in Japanese Unexamined Patent Application Publication No. 2022-033487 and Japanese Unexamined Patent Application Publication No. 2016-038418 are known. Summary of the Invention

[0003] There is a need for a small-sized imaging lens with good optical performance. These requirements are increasing year by year.

[0004] An object of the present invention is to provide a small-sized imaging lens with good optical performance and a photographing device equipped with the imaging lens.

[0005] Means for Solving the Technical Problem

[0006] A first aspect of the present invention is an imaging lens that sequentially includes a front group, an aperture, and a rear group from the object side to the image side. The front group sequentially and continuously includes a first lens that is a negative lens with a concave surface facing the image side and a second lens that is a negative lens with a concave surface facing the image side from the object side closest to the object to the image side. Two or fewer focusing lens groups are arranged on the image side of the second lens. During focusing, the two or fewer focusing lens groups move along the optical axis, and lenses other than the two or fewer focusing lens groups are fixed relative to the image plane. When the back focal length in the air-converted distance of the entire system in the state of focusing on an infinitely distant object is set as Bf, the focal length of the entire system in the state of focusing on an infinitely distant object is set as f, and the maximum half-angle in the state of focusing on an infinitely distant object is set as ωm, the imaging lens satisfies the following conditional expression (1):

[0007] 0.3 < Bf / (f × tan ωm) < 1.5 (1).

[0008] A second aspect of the present invention is the imaging lens according to the first aspect. When the distance on the optical axis from the lens surface closest to the object of the imaging lens to the aperture in the state of focusing on an infinitely distant object is set as STI, and the sum of the distance on the optical axis from the lens surface closest to the object of the imaging lens to the lens surface closest to the image side of the imaging lens and the back focal length in the air-converted distance of the entire system is set as TL, the imaging lens satisfies the following conditional expression (2):

[0009] 0.3 < STI / TL < 0.75 (2).

[0010] In the third aspect of the present invention, in the imaging lens of the first aspect, when the focal length of the front group in the state of focusing on an infinitely distant object is set as fF and the focal length of the rear group in the state of focusing on an infinitely distant object is set as fR, the imaging lens satisfies the conditional expression (3) represented as follows:

[0011] -2 < fR / fF < 4 (3).

[0012] In the fourth aspect of the present invention, in the imaging lens of the first aspect, when the paraxial curvature radius of the object-side surface of the first lens is set as RL1f, the imaging lens satisfies the conditional expression (4) represented as follows:

[0013] -0.3 < f / RL1f < 8 (4).

[0014] In the fifth aspect of the present invention, in the imaging lens of the first aspect, when the paraxial curvature radius of the image-side surface of the first lens is set as RL1r, the imaging lens satisfies the conditional expression (5) represented as follows:

[0015] 0 < f / RL1r < 4 (5).

[0016] In the sixth aspect of the present invention, in the imaging lens of the first aspect, when the focal length of the front group in the state of focusing on an infinitely distant object is set as fF, the imaging lens satisfies the conditional expression (6) represented as follows:

[0017] -1 < f / fF < 2 (6).

[0018] In the seventh aspect of the present invention, in the imaging lens of the first aspect, when the maximum photographing magnification of the imaging lens is set as β, the imaging lens satisfies the conditional expression (7) represented as follows:

[0019] 0.06 < |β| < 0.5 (7).

[0020] In the eighth aspect of the present invention, in the imaging lens of the first aspect, when the sum of the distance on the optical axis from the lens surface closest to the object of the imaging lens to the lens surface closest to the image of the imaging lens in the state of focusing on an infinitely distant object and the back focal length under the air-converted distance of the entire system is set as TL, the imaging lens satisfies the conditional expression (8) represented as follows:

[0021] 3 < TL / (f × tanωm) < 7 (8).

[0022] In the ninth aspect of the present invention, in the imaging lens of the first aspect, when the open F value in the state of focusing on an infinitely distant object is set as FNo, the imaging lens satisfies the conditional expression (9) represented as follows:

[0023] 0.55 < FNo / tanωm < 2 (9).

[0024] In the imaging lens according to the 1st aspect of the present invention, when the Abbe number of the 1st lens with respect to the d-line is νL1, the imaging lens satisfies the conditional expression (10) represented below:

[0025] 20 < νL1 < 95 (10).

[0026] In the imaging lens according to the 11th aspect of the present invention, when the sum of the distance on the optical axis from the lens surface closest to the object side of the imaging lens to the lens surface closest to the image side of the imaging lens in the state of focusing on an infinitely distant object and the back focal length in terms of air of the entire system is TL, the imaging lens satisfies the conditional expression (8-3) represented below:

[0027] 3.5 < TL / (f × tanωm) < 5.65 (8-3).

[0028] In the imaging lens according to the 12th aspect of the present invention, when the open F-number in the state of focusing on an infinitely distant object is FNo, the imaging lens satisfies the conditional expression (9-3) represented below:

[0029] 0.7 < FNo / tanωm < 1.35 (9-3).

[0030] In the imaging lens according to the 13th aspect of the present invention, when the Abbe number of the 1st lens with respect to the d-line is νL1, the imaging lens satisfies the conditional expression (10-1) represented below:

[0031] 28 < νL1 < 59 (10-1).

[0032] In the imaging lens according to the 14th aspect of the present invention, the imaging lens includes only one focusing lens group, the focusing lens group is arranged in the rear group, and when the focal length of the focusing lens group is ff, the imaging lens satisfies the conditional expression (11) represented below:

[0033] 0.05 < |f / ff| < 0.9 (11).

[0034] In the imaging lens according to the 15th aspect of the present invention, the imaging lens includes only one focusing lens group, the focusing lens group is arranged in the rear group, and when the focal length of the focusing lens group is ff and the sum of the distance on the optical axis from the lens surface closest to the object side of the imaging lens to the lens surface closest to the image side of the imaging lens in the state of focusing on an infinitely distant object and the back focal length in terms of air of the entire system is TL, the imaging lens satisfies the conditional expression (12) represented below:

[0035] 0.1 < |TL / ff| < 6 (12).

[0036] In the imaging lens of the 14th aspect of the present invention, when the combined focal length of all lenses on the image side with respect to the focusing lens group is set as ff_r, this imaging lens satisfies the conditional expression (13) represented below:

[0037] 0.05 < f / ff_r < 1.5 (13).

[0038] In the imaging lens of the 14th aspect of the present invention, when the combined focal length of all lenses on the object side with respect to the focusing lens group is set as ff_f, this imaging lens satisfies the conditional expression (14) represented below:

[0039] -3 < f / ff_f < 0 (14).

[0040] In the imaging lens of the 14th aspect of the present invention, when the sum of the distance on the optical axis from the lens surface closest to the object side of the imaging lens to the lens surface closest to the image side of the imaging lens in the state of focusing on an infinitely distant object and the back focal length under the air-converted distance of the entire system is set as TL, this imaging lens satisfies the conditional expression (8-1) represented below:

[0041] 3.2 < TL / (f × tanωm) < 6.5 (8-1).

[0042] In the imaging lens of the 18th aspect of the present invention, when the open F value in the state of focusing on an infinitely distant object is set as FNo, this imaging lens satisfies the conditional expression (9-3) represented below:

[0043] 0.7 < FNo / tanωm < 1.35 (9-3).

[0044] In the imaging lens of the 19th aspect of the present invention, when the Abbe number based on the d line of the first lens is set as νL1, this imaging lens satisfies the conditional expression (10-1) represented below:

[0045] 28 < νL1 < 59 (10-1).

[0046] In the imaging lens of the 1st aspect of the present invention, the imaging lens includes only one focusing lens group, and the focusing lens group is arranged in the front group.

[0047] In the 22nd aspect of the present invention, in the imaging lens of the 21st aspect, when the sum of the distance on the optical axis from the lens surface closest to the object side of the imaging lens to the lens surface closest to the image side of the imaging lens in the state of focusing on an infinitely distant object and the back focal length in terms of air of the entire system is set as TL, this imaging lens satisfies the conditional expression (8-2) shown below:

[0048] 3.4 < TL / (f × tanωm) < 5.9 (8-2).

[0049] In the 23rd aspect of the present invention, in the imaging lens of the 22nd aspect, when the open F value in the state of focusing on an infinitely distant object is set as FNo, this imaging lens satisfies the conditional expression (9-2) shown below:

[0050] 0.66 < FNo / tanωm < 1.55 (9-2).

[0051] In the 24th aspect of the present invention, in the imaging lens of the 1st aspect, the focusing lens group includes an aperture, and during focusing, the aperture moves along the optical axis.

[0052] In the 25th aspect of the present invention, in the imaging lens of the 24th aspect, the imaging lens includes only one focusing lens group. When the focal length of the focusing lens group is set as ffs, this imaging lens satisfies the conditional expression (15) shown below:

[0053] 0.1 < f / ffs < 0.5 (15).

[0054] In the 26th aspect of the present invention, in the imaging lens of the 24th aspect, when the sum of the distance on the optical axis from the lens surface closest to the object side of the imaging lens to the lens surface closest to the image side of the imaging lens in the state of focusing on an infinitely distant object and the back focal length in terms of air of the entire system is set as TL, this imaging lens satisfies the conditional expression (8-2) shown below:

[0055] 3.4 < TL / (f × tanωm) < 5.9 (8-2).

[0056] In the 27th aspect of the present invention, in the imaging lens of the 26th aspect, when the open F value in the state of focusing on an infinitely distant object is set as FNo, this imaging lens satisfies the conditional expression (9) shown below:

[0057] 0.55 < FNo / tanωm < 2 (9).

[0058] In the 28th aspect of the present invention, in the imaging lens of the 24th aspect, when the sum of the distance on the optical axis from the lens surface closest to the object side of the imaging lens to the lens surface closest to the image side of the imaging lens in the state of focusing on an infinitely distant object and the back focal length in terms of air of the entire system is set as TL, this imaging lens satisfies the conditional expression (8) represented below:

[0059] 3 < TL / (f × tanωm) < 7 (8).

[0060] In the 29th aspect of the present invention, in the imaging lens of the 28th aspect, when the open F-number in the state of focusing on an infinitely distant object is set as FNo, this imaging lens satisfies the conditional expression (9-1) represented below:

[0061] 0.64 < FNo / tanωm < 1.62 (9-1).

[0062] In the 30th aspect of the present invention, in the imaging lens of the 1st aspect, the imaging lens includes two focusing lens groups. When the focusing lens group on the object side among the two focusing lens groups is set as the first focusing lens group and the focusing lens group on the image side is set as the second focusing lens group, during focusing, the first focusing lens group and the second focusing lens group move with different moving amounts.

[0063] In the 31st aspect of the present invention, in the imaging lens of the 30th aspect, when the sum of the distance on the optical axis from the lens surface closest to the object side of the imaging lens to the lens surface closest to the image side of the imaging lens in the state of focusing on an infinitely distant object and the back focal length in terms of air of the entire system is set as TL, this imaging lens satisfies the conditional expression (8-2) represented below:

[0064] 3.4 < TL / (f × tanωm) < 5.9 (8-2).

[0065] In the 32nd aspect of the present invention, in the imaging lens of the 31st aspect, when the open F-number in the state of focusing on an infinitely distant object is set as FNo, this imaging lens satisfies the conditional expression (9-2) represented below:

[0066] 0.66 < FNo / tanωm < 1.55 (9-2).

[0067] In the 33rd aspect of the present invention, in the imaging lens of the 30th aspect, the first focusing lens group is arranged in the front group and the second focusing lens group is arranged in the rear group.

[0068] In the 34th aspect of the present invention, in the imaging lens of the 33rd aspect, when the sum of the distance on the optical axis from the lens surface closest to the object side of the imaging lens to the lens surface closest to the image side of the imaging lens in the state of focusing on an infinitely distant object and the back focal length in terms of air conversion distance of the entire system is set as TL, this imaging lens satisfies the conditional expression (8) shown below:

[0069] 3 < TL / (f × tanωm) < 7 (8).

[0070] In the 35th aspect of the present invention, in the imaging lens of the 34th aspect, when the open F-number in the state of focusing on an infinitely distant object is set as FNo, this imaging lens satisfies the conditional expression (9-2) shown below:

[0071] 0.66 < FNo / tanωm < 1.55 (9-2).

[0072] In the 36th aspect of the present invention, in the imaging lens of the 35th aspect, it satisfies the conditional expression (1-1) shown below:

[0073] 0.43 < Bf / (f × tanωm) < 1.1 (1-1).

[0074] In the 37th aspect of the present invention, in the imaging lens of the 36th aspect, when the Abbe number of the first lens based on the d-line is set as νL1, this imaging lens satisfies the conditional expression (10) shown below:

[0075] 20 < νL1 < 95 (10).

[0076] In the 38th aspect of the present invention, in the imaging lens of the 30th aspect, when the focal length of the first focusing lens group is set as ff1 and the focal length of the second focusing lens group is set as ff2, this imaging lens satisfies the conditional expression (16) shown below:

[0077] 0.2 < |ff1 / ff2| < 5 (16).

[0078] In the 39th aspect of the present invention, in the imaging lens of the 30th aspect, when the lateral magnification of the first focusing lens group in the state of focusing on an infinitely distant object is set as βf1 and the lateral magnification of the second focusing lens group in the state of focusing on an infinitely distant object is set as βf2, this imaging lens satisfies the conditional expression (17) shown below:

[0079] 0 < |βf1 / βf2| < 0.6 (17).

[0080] In the 40th aspect of the present invention, in the imaging lens of the 30th aspect, when the lateral magnification of the first focusing lens group in the state of focusing on an infinitely distant object is set to βf1, the imaging lens satisfies the conditional expression (18) represented as follows:

[0081] 0 < {βf1 + (1 / βf1)} -2 < 0.25 (18).

[0082] In the 41st aspect of the present invention, in the imaging lens of the 30th aspect, when the lateral magnification of the second focusing lens group in the state of focusing on an infinitely distant object is set to βf2, the imaging lens satisfies the conditional expression (19) represented as follows:

[0083] 0 < {βf2 + (1 / βf2)} -2 < 0.25 (19).

[0084] In the 42nd aspect of the present invention, in the imaging lens of the 30th aspect, when the combined focal length of all lenses on the image side with respect to the second focusing lens group is set to f2r, the imaging lens satisfies the conditional expression (20) represented as follows:

[0085] 0.1 < f / f2r < 2 (20).

[0086] In the 43rd aspect of the present invention, in the imaging lens of the 30th aspect, when the combined focal length of all lenses on the object side with respect to the first focusing lens group is set to f1f, the imaging lens satisfies the conditional expression (21) represented as follows:

[0087] -3 < f / f1f < 2 (21).

[0088] In the 44th aspect of the present invention, in the imaging lens of the 1st aspect, when the focal length of the first lens is set to fL1 and the focal length of the second lens is set to fL2, the imaging lens satisfies the conditional expression (22) represented as follows:

[0089] 0 < fL1 / fL2 < 5.5 (22).

[0090] In the 45th aspect of the present invention, in the imaging lens of the 1st aspect, when the focal length of the first lens is set to fL1, the imaging lens satisfies the conditional expression (23) represented as follows:

[0091] -8 < fL1 / f < -0.5 (23).

[0092] In the 46th aspect of the present invention, in the imaging lens of the 1st aspect, when the paraxial curvature radius of the object-side surface of the 1st lens is RL1f and the paraxial curvature radius of the image-side surface of the 1st lens is RL1r, the imaging lens satisfies the conditional expression (24) represented as follows:

[0093] -2.5 < (RL1r - RL1f) / (RL1r + RL1f) < -0.1 (24).

[0094] In the 47th aspect of the present invention, in the imaging lens of the 1st aspect, when the paraxial curvature radius of the object-side surface of the 2nd lens is RL2f and the paraxial curvature radius of the image-side surface of the 2nd lens is RL2r, the imaging lens satisfies the conditional expression (25) represented as follows:

[0095] -1.5 < (RL2r - RL2f) / (RL2r + RL2f) < -0.05 (25).

[0096] In the 48th aspect of the present invention, in the imaging lens of the 1st aspect, a 3rd lens as a negative lens is disposed adjacent to the image side of the 2nd lens, and a 4th lens as a positive lens is disposed adjacent to the image side of the 3rd lens. When the focal length of the 3rd lens is fL3 and the focal length of the 4th lens is fL4, the imaging lens satisfies the conditional expression (26) represented as follows:

[0097] -8 < fL3 / fL4 < 0 (26).

[0098] In the 49th aspect of the present invention, in the imaging lens of the 1st aspect, when the paraxial curvature radius of the object-side surface of the lens closest to the image side of the imaging lens is RLef and the paraxial curvature radius of the image-side surface of the lens closest to the image side of the imaging lens is Rler, the imaging lens satisfies the conditional expression (27) represented as follows:

[0099] 0.4 < (Rler - RLef) / (Rler + RLef) < 5.5 (27).

[0100] In the 50th aspect of the present invention, in the imaging lens of the 1st aspect, at least one of the object-side surface and the image-side surface of the 1st lens is an aspherical surface. When the paraxial curvature radius of the object-side surface of the 1st lens is RL1f, the paraxial curvature radius of the image-side surface of the 1st lens is RL1r, the curvature radius at the position of the maximum effective diameter of the object-side surface of the 1st lens is RyL1f, and the curvature radius at the position of the maximum effective diameter of the image-side surface of the 1st lens is RyL1r, the imaging lens satisfies the conditional expression (28) represented as follows:

[0101] 0.5 < (1 / RL1f - 1 / RL1r) / (1 / RyL1f - 1 / RyL1r) < 7 (28).

[0102] In the imaging lens according to the 50th aspect of the present invention, when the Abbe number of the first lens with respect to the d-line is νL1, the imaging lens satisfies the conditional expression (10-2) represented below:

[0103] 32 < νL1 < 48 (10-2).

[0104] In the imaging lens according to the 52nd aspect of the present invention, the front group includes at least one positive lens. When the focal length of the positive lens having the strongest optical power among the positive lenses included in the front group is fFp, the imaging lens satisfies the conditional expression (29) represented below:

[0105] 0.1 < f / fFp < 3 (29).

[0106] In the imaging lens according to the 53rd aspect of the present invention, the rear group includes at least one positive lens. When the focal length of the positive lens having the strongest optical power among the positive lenses included in the rear group is fRp and the focal length of the rear group in a state of focusing on an infinitely distant object is fR, the imaging lens satisfies the conditional expression (30) represented below:

[0107] 0.3 < fR / fRp < 5 (30).

[0108] In the imaging lens according to the 54th aspect of the present invention, the rear group includes a cemented lens formed by sequentially cementing a positive lens with its convex surface facing the object side and a negative lens from the object side. When the Abbe number of the positive lens of the cemented lens with respect to the d-line is νRp and the Abbe number of the negative lens of the cemented lens with respect to the d-line is νRn, the imaging lens satisfies the conditional expression (31) represented below:

[0109] 10 < νRp - νRn < 75 (31).

[0110] In the imaging lens according to the 55th aspect of the present invention, when the refractive index of the positive lens of the cemented lens with respect to the d-line is NRp and the refractive index of the negative lens of the cemented lens with respect to the d-line is NRn, the imaging lens satisfies the conditional expression (32) represented below:

[0111] 0.2 < NRp - NRn < 0.9 (32).

[0112] In the imaging lens according to the 56th aspect of the present invention, an LFe lens as a positive lens is disposed on the image side most adjacent to the front group.

[0113] In the 57th aspect of the present invention, in the imaging lens of the 56th aspect, the LFe lens is a biconvex lens.

[0114] In the 58th aspect of the present invention, in the imaging lens of the 56th aspect, at least one of the object-side surface and the image-side surface of the LFe lens is an aspherical surface. When the paraxial curvature radius of the object-side surface of the LFe lens is set as RcLFef, the paraxial curvature radius of the image-side surface of the LFe lens is set as RcLFer, the curvature radius at the position of the maximum effective diameter of the object-side surface of the LFe lens is set as RyLFef, and the curvature radius at the position of the maximum effective diameter of the image-side surface of the LFe lens is set as RyLFer, this imaging lens satisfies the conditional expression (33) represented as follows:

[0115] 0.5 < (1 / RcLFef - 1 / RcLFer) / (1 / RyLFef - 1 / RyLFer) < 7 (33).

[0116] In the 59th aspect of the present invention, in the imaging lens of the 56th aspect, when the paraxial curvature radius of the object-side surface of the LFe lens is set as RcLFef and the paraxial curvature radius of the image-side surface of the LFe lens is set as RcLFer, this imaging lens satisfies the conditional expression (34) represented as follows:

[0117] -4 < (RcLFef - RcLFer) / (RcLFef + RcLFer) < 10 (34).

[0118] In the 60th aspect of the present invention, in the imaging lens of the 56th aspect, when the Abbe number of the LFe lens based on the d line is set as νLFe, this imaging lens satisfies the conditional expression (35) represented as follows:

[0119] 15 < νLFe < 90 (35).

[0120] In the 61st aspect of the present invention, in the imaging lens of the 1st aspect, when the central thickness of the 1st lens is set as D1 and the sum of the distance on the optical axis from the lens surface closest to the object of the imaging lens to the lens surface closest to the image of the imaging lens in the state of focusing on an infinitely distant object and the back focal length under the air-converted distance of the entire system is set as TL, this imaging lens satisfies the conditional expression (36) represented as follows:

[0121] 0.007 < D1 / TL < 0.1 (36).

[0122] In the 62nd aspect of the present invention, in the imaging lens of the 1st aspect, when the thickness of the 1st lens in the optical axis direction at the height of the maximum effective diameter of the image-side surface of the 1st lens is set as DH1 and the central thickness of the 1st lens is set as D1, this imaging lens satisfies the conditional expression (37) shown below:

[0123] 2 < DH1 / D1 < 10 (37).

[0124] In the 63rd aspect of the present invention, in the imaging lens of the 1st aspect, when the Abbe number of the lens closest to the image side of the imaging lens based on the d line is set as νLe, this imaging lens satisfies the conditional expression (38) shown below:

[0125] 30 < νLe < 95 (38).

[0126] In the 64th aspect of the present invention, in the imaging lens of the 1st aspect, when the effective radius of the object-side surface of the 1st lens is set as EL1, this imaging lens satisfies the conditional expression (39) shown below:

[0127] 0.7 < EL1 / (f × tan ωm) < 2 (39).

[0128] In the 65th aspect of the present invention, in the imaging lens of the 1st aspect, when including an Ls lens on the image side more than the 2nd lens, and when the refractive index of the Ls lens with respect to the d line is set as NLs, the Abbe number of the Ls lens based on the d line is set as νLs, and the partial dispersion ratio between the g line and the F line of the Ls lens is set as θgFLs, the imaging lens satisfies the conditional expressions (40), (41), (42), and (43) shown below:

[0129] 0.005 < NLs - (2.015 - 0.0068 × νLs) < 0.15 (40)

[0130] 49.8 < νLs < 65 (41)

[0131] 0.543 < θgFLs < 0.58 (42)

[0132] -0.011 < θgFLs - (0.6418 - 0.00168 × νLs) < 0.035 (43).

[0133] In the 66th aspect of the present invention, in the imaging lens of the 65th aspect, when the sum of the distance on the optical axis from the lens surface closest to the object side of the imaging lens to the lens surface closest to the image side of the imaging lens in the state of focusing on an infinite object and the back focal length under the air-converted distance of the entire system is set as TL, this imaging lens satisfies the conditional expression (8 - 3) shown below:

[0134] 3.5 < TL / (f × tan ωm) < 5.65 (8 - 3).

[0135] In the 67th aspect of the present invention, in the imaging lens of the 66th aspect, when the open F-number in the state of focusing on an infinitely distant object is set as FNo, the imaging lens satisfies the conditional expression (9) represented below:

[0136] 0.55 < FNo / tan ωm < 2 (9).

[0137] The 68th aspect of the present invention is an imaging device including the imaging lens of any one of the 1st aspect to the 67th aspect.

[0138] In addition, "including ~" and "comprising ~" in this specification mean that, in addition to the constituent elements listed, it may also include a lens having substantially no optical power, and optical elements other than lenses such as a diaphragm, a filter, and a cover glass, as well as mechanical parts such as a lens flange, a lens barrel, an imaging element, and a shake correction mechanism.

[0139] "~ group having a positive optical power" in this specification means that the group as a whole has a positive optical power. Similarly, "~ group having a negative optical power" means that the group as a whole has a negative optical power. The "focusing lens group", "first focusing lens group", "second focusing lens group", and "single focusing lens group" in this specification are not limited to a structure including a plurality of lenses, and may also be configured to include only one lens.

[0140] A compound aspherical lens (a lens in which a spherical lens and an aspherical shape film formed on the spherical lens are integrated and function as one aspherical lens as a whole) is used as one lens and is not regarded as a cemented lens. Unless otherwise specified, the radius of curvature, the sign of the optical power, and the surface shape related to a lens including an aspherical surface use the radius of curvature, the sign of the optical power, and the surface shape in the paraxial region. Regarding the sign of the radius of curvature, the sign of the radius of curvature of the surface with the convex shape facing the object side is set as positive, and the sign of the radius of curvature of the surface with the convex shape facing the image side is set as negative.

[0141] "The entire system" in this specification means the imaging lens. 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 values used in the conditional expression are the values based on the d-line in the state of focusing on an infinitely distant object.

[0142] In this specification, the "d-line", "C-line", "F-line", and "g-line" are bright lines. The wavelength of the d-line is regarded as 587.56 nm (nanometers), the wavelength of the C-line is regarded as 656.27 nm (nanometers), the wavelength of the F-line is regarded as 486.13 nm (nanometers), and the wavelength of the g-line is regarded as 435.84 nm (nanometers).

[0143] When the refractive indices of a certain lens with respect to the g-line, F-line, and C-line are set as Ng, NF, and NC respectively, and the partial dispersion ratio between the g-line and F-line of the lens is set as θgF, θgF is defined by the following formula.

[0144] θgF = (Ng - NF) / (NF - NC)

[0145] Advantages of the Invention

[0146] According to the present invention, it is possible to provide an imaging lens that is small in size and has good optical performance, and an imaging device including the imaging lens. Description of the Drawings

[0147] Figure 1 It is a cross-sectional view showing the structure of an imaging lens according to an embodiment corresponding to the imaging lens of Embodiment 1.

[0148] Figure 2 It shows Figure 1 a cross-sectional view of the structure of the imaging lens and light beams.

[0149] Figure 3 It is a diagram for explaining the positions of the effective radius and the maximum effective diameter.

[0150] Figure 4 It is an aberration diagram of the imaging lens of Embodiment 1.

[0151] Figure 5 It is a cross-sectional view showing the structure of the imaging lens of Embodiment 2.

[0152] Figure 6 It is an aberration diagram of the imaging lens of Embodiment 2.

[0153] Figure 7 It is a cross-sectional view showing the structure of the imaging lens of Embodiment 3.

[0154] Figure 8 It is an aberration diagram of the imaging lens of Embodiment 3.

[0155] Fig. 9 It is a cross-sectional view showing the structure of the imaging lens of Embodiment 4.

[0156] Fig.10 It is an aberration diagram of the imaging lens of Embodiment 4.

[0157] Fig.11 It is a cross-sectional view showing the structure of the imaging lens of Example 5.

[0158] Fig.12 They are aberration diagrams of the imaging lens of Example 5.

[0159] Fig.13 It is a cross-sectional view showing the structure of the imaging lens of Example 6.

[0160] Fig.14 They are aberration diagrams of the imaging lens of Example 6.

[0161] Fig.15 It is a cross-sectional view showing the structure of the imaging lens of Example 7.

[0162] Fig.16 They are aberration diagrams of the imaging lens of Example 7.

[0163] Fig.17 It is a cross-sectional view showing the structure of the imaging lens of Example 8.

[0164] Fig.18 They are aberration diagrams of the imaging lens of Example 8.

[0165] Fig.19 It is a cross-sectional view showing the structure of the imaging lens of Example 9.

[0166] Fig. 20 They are aberration diagrams of the imaging lens of Example 9.

[0167] Fig.21 It is a cross-sectional view showing the structure of the imaging lens of Example 10.

[0168] Fig. 22 They are aberration diagrams of the imaging lens of Example 10.

[0169] Fig.23 It is a cross-sectional view showing the structure of the imaging lens of Example 11.

[0170] Fig.24 They are aberration diagrams of the imaging lens of Example 11.

[0171] Fig.25 It is a cross-sectional view showing the structure of the imaging lens of Example 12.

[0172] Fig.26 They are aberration diagrams of the imaging lens of Example 12.

[0173] Fig. 27 It is a cross-sectional view showing the structure of the imaging lens of Example 13.

[0174] Fig.28They are aberration diagrams of the imaging lens of Example 13.

[0175] Fig.29 It is a cross-sectional view showing the structure of the imaging lens of Example 14.

[0176] Fig.30 They are aberration diagrams of the imaging lens of Example 14.

[0177] Fig.31 It is a cross-sectional view showing the structure of the imaging lens of Example 15.

[0178] Fig.32 They are aberration diagrams of the imaging lens of Example 15.

[0179] Fig.33 It is a cross-sectional view showing the structure of the imaging lens of Example 16.

[0180] Fig.34 They are aberration diagrams of the imaging lens of Example 16.

[0181] Fig.35 It is a cross-sectional view showing the structure of the imaging lens of Example 17.

[0182] Fig.36 They are aberration diagrams of the imaging lens of Example 17.

[0183] Fig.37 It is a cross-sectional view showing the structure of the imaging lens of Example 18.

[0184] Fig.38 They are aberration diagrams of the imaging lens of Example 18.

[0185] Fig.39 It is a cross-sectional view showing the structure of the imaging lens of Example 19.

[0186] Fig.40 They are aberration diagrams of the imaging lens of Example 19.

[0187] Fig.41 It is a cross-sectional view showing the structure of the imaging lens of Example 20.

[0188] Fig.42 They are aberration diagrams of the imaging lens of Example 20.

[0189] Fig.43 It is a cross-sectional view showing the structure of the imaging lens of Example 21.

[0190] Fig.44 They are aberration diagrams of the imaging lens of Example 21.

[0191] Fig.45It is a perspective view of the front side of the imaging device according to an embodiment.

[0192] Fig.46 It is a perspective view of the back side of the imaging device according to an embodiment. Detailed Embodiment

[0193] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0194] In Figure 1 a cross-sectional view showing the structure of the imaging lens according to an embodiment of the present invention is shown. In Figure 2 a cross-sectional view showing the structure of the imaging lens and the light beam in Figure 1 is shown. In Figure 2 the on-axis light beam and the light beam with the maximum half-angle ωm are shown as the light beams. In Figure 1 and Figure 2 the left side is the object side, the right side is the image side, and the state of focusing on an infinitely distant object is shown. In this specification, an object located at an infinite distance is referred to as an infinitely distant object. Figure 1 and Figure 2 The example shown corresponds to the imaging lens of Example 1 described later. Hereinafter, mainly with reference to Figure 1 it will be described.

[0195] The imaging lens of the present invention sequentially includes a front group GF, an aperture stop St, and a rear group GR along the optical axis Z from the object side to the image side. The front group GF sequentially and continuously includes a first lens as a negative lens with a concave surface facing the image side and a second lens as a negative lens with a concave surface facing the image side from the object side closest to the image side. The front group GF having the above structure functions as a wide-angle converter, and by sharing the negative optical power on the object side by the first lens and the second lens, it is beneficial to correct various aberrations such as distortion aberration and field curvature. And, by arranging the first lens and the second lens as described above, it is beneficial to ensure the viewing angle while suppressing various aberrations.

[0196] As an example, Figure 1 each group of the imaging lens is configured as follows. The front group GF sequentially includes seven lenses L11 to L17 from the object side to the image side. The rear group GR sequentially includes six lenses L21 to L26 from the object side to the image side. In Figure 1 the example of Figure 1 the aperture stop St represents the position in the optical axis direction, and does not represent the size and shape. This method of showing the aperture stop St is the same in other cross-sectional views.

[0197] In the imaging lens of the present invention, there are two or less focusing lens groups disposed on the image side with respect to the second lens. During focusing, the two or less focusing lens groups move along the optical axis Z, and the lenses other than the two or less focusing lens groups are fixed with respect to the image plane Sim. During focusing, by moving the lens group on the image side with respect to the second lens, it is possible to suppress the change in the viewing angle during focusing.

[0198] As an example, Figure 1 the imaging lens has two focusing lens groups. By having two focusing lens groups, it is possible to suppress the amount of movement of each focusing lens group, which is advantageous for high-speed focusing.

[0199] Hereinafter, in the structure where the imaging lens has two focusing lens groups, the focusing lens group on the object side among the two focusing lens groups is referred to as the first focusing lens group Gf1, and the focusing lens group on the image side is referred to as the second focusing lens group Gf2. During focusing, the first focusing lens group Gf1 and the second focusing lens group Gf2 move with different amounts of movement. By moving the two focusing lens groups with different amounts of movement, it is possible to satisfactorily suppress the aberration change accompanying the change in the shooting distance.

[0200] As an example, in Figure 1 the imaging lens, the first focusing lens group Gf1 includes the lens L15, and the second focusing lens group Gf2 includes the lenses L16 and L17. In Figure 1 , the direction of movement of each focusing lens group during focusing from an infinitely distant object to the nearest object is indicated by an arrow. In Figure 1 the example, when focusing from an infinitely distant object to the nearest object, the first focusing lens group Gf1 moves toward the image side, and the second focusing lens group Gf2 moves toward the object side.

[0201] In the imaging lens of the present invention, it may be configured such that a positive lens is disposed on the most image-side of the front group GF. In such a configuration, it is advantageous for correcting spherical aberration. Hereinafter, for the sake of convenience of explanation, the positive lens disposed on the most image-side of the front group GF is referred to as the LFe lens. The LFe lens is preferably a biconvex lens.

[0202] In such a configuration, it is advantageous for correcting spherical aberration. In Figure 1 the example, the lens L17 corresponds to the LFe lens.

[0203] The rear group GR may be configured to include a cemented lens formed by sequentially cementing a positive lens with the convex surface facing the object side and a negative lens. In such a configuration, it is advantageous for correcting chromatic aberration.

[0204] The lens closest to the image side of the rear group GR can be configured as a positive lens. In such a configuration, it is possible to suppress the increase in the incident angle of the chief ray off the axis to the image plane Sim, and thus it is beneficial to ensure the peripheral light quantity.

[0205] The preferred structure of the imaging lens of the present invention related to the conditional expressions will be described below. In the following description of the conditional expressions, in order to avoid redundancy, the same notations are used for the parts with the same definitions, and the repeated description of the notations is omitted. Also, hereinafter, in order to avoid redundancy, the "imaging lens of the present invention" is also simply referred to as the "imaging lens".

[0206] The imaging lens preferably satisfies the following conditional expression (1). Here, the back focal length in the air equivalent distance of the entire system in the state of focusing on an infinitely distant object is set as Bf. The focal length of the entire system in the state of focusing on an infinitely distant object is set as f. The maximum half angle in the state of focusing on an infinitely distant object is set as ωm. The back focal length Bf in the air equivalent distance is the air equivalent distance on the optical axis from the lens surface closest to the image side of the imaging lens to the image plane Sim. As an example, Figure 2 the back focal length Bf is shown. Tan is the tangent. By preventing the corresponding value of the conditional expression (1) from falling below the lower limit, it is possible to suppress the increase in the diameter of the lens closest to the image side of the imaging lens. By preventing the corresponding value of the conditional expression (1) from exceeding the upper limit, it is beneficial to shorten the total length of the optical system.

[0207] 0.3 < Bf / (f × tan ωm) < 1.5 (1)

[0208] In order to obtain better characteristics, it is preferably set to any one of 0.35, 0.4, 0.43, and 0.45 instead of the lower limit 0.3 of the conditional expression (1). And it is preferably set to any one of 1.3, 1.2, 1.1, and 1 instead of the upper limit 1.5 of the conditional expression (1). For example, the imaging lens more preferably satisfies the following conditional expression (1-1).

[0209] 0.43 < Bf / (f × tan ωm) < 1.1 (1-1)

[0210] The imaging lens preferably satisfies the following conditional expression (2). Here, the distance on the optical axis from the lens surface closest to the object side of the imaging lens to the aperture stop St in the state of focusing on an infinitely distant object is set as STI. The sum of the distance on the optical axis from the lens surface closest to the object side of the imaging lens to the lens surface closest to the image side of the imaging lens and the back focal length Bf in the air equivalent distance of the entire system in the state of focusing on an infinitely distant object is set as TL. TL is the total length of the lens system. As an example, in Figure 2The distance STI and the total length TL of the lens system are shown. By preventing the corresponding value of conditional expression (2) from falling below the lower limit, it is possible to sufficiently ensure the space on the object side with respect to the aperture stop St. Therefore, it is possible to arrange an appropriate number of lenses without forcibly reducing the absolute value of the curvature radius of the lenses. As a result, it is easy to appropriately correct various aberrations. By preventing the corresponding value of conditional expression (2) from exceeding the upper limit, it is possible to prevent the position of the aperture stop St from being too close to the image plane Sim, and therefore it is possible to prevent the incident angle of the chief ray off the axis incident on the imaging element arranged on the image plane Sim in the imaging device from becoming too large.

[0211] 0.3 < STI / TL < 0.75 (2)

[0212] In order to obtain better characteristics, it is preferable to set it to 0.35 or 0.4 instead of the lower limit 0.3 of conditional expression (2). Also, it is preferable to set it to 0.7 or 0.65 instead of the upper limit 0.75 of conditional expression (2).

[0213] The imaging lens preferably satisfies the following conditional expression (3). Here, the focal length of the front group GF in the state of focusing on an object at infinity is set to fF. The focal length of the rear group GR in the state of focusing on an object at infinity is set to fR. Conditional expression (3) is an expression for appropriately setting the ratio of the optical power of the front group GF to the optical power of the rear group GR. The front group GF functions as a wide-angle converter that expands the viewing angle and sufficiently ensures the back focal length in the entire optical system. By preventing the corresponding value of conditional expression (3) from falling below the lower limit, it is possible to suppress various aberrations such as spherical aberration. By preventing the corresponding value of conditional expression (3) from exceeding the upper limit, it is beneficial for achieving a wide viewing angle.

[0214] -2 < fR / fF < 4 (3)

[0215] In order to obtain better characteristics, it is preferable to set it to any one of -1.5, -1, and -0.7 instead of the lower limit -2 of conditional expression (3). Also, it is preferable to set it to any one of 3.5, 3, and 2.5 instead of the upper limit 4 of conditional expression (3).

[0216] When the paraxial curvature radius of the object-side surface of the first lens is set to RL1f, the imaging lens preferably satisfies the following conditional expression (4). By preventing the corresponding value of conditional expression (4) from falling below the lower limit, it is beneficial for correcting distortion aberration. By preventing the corresponding value of conditional expression (4) from exceeding the upper limit, it is beneficial for correcting astigmatism.

[0217] -0.3 < f / RL1f < 8(4)

[0218] In order to obtain better characteristics, it is preferably set to any one of -0.2, -0.1, and 0 to replace the lower limit -0.3 of conditional expression (4). Also, it is preferably set to any one of 4, 1, and 0.4 to replace the upper limit 8 of conditional expression (4).

[0219] When the paraxial curvature radius of the image-side surface of the first lens is RL1r, the imaging lens preferably satisfies the following conditional expression (5). By preventing the corresponding value of conditional expression (5) from falling below the lower limit, it is beneficial for correcting distortion aberration. By preventing the corresponding value of conditional expression (5) from exceeding the upper limit, it is beneficial for correcting astigmatism.

[0220] 0 < f / RL1r < 4 (5)

[0221] In order to obtain better characteristics, it is preferably set to any one of 0.15, 0.25, 0.35, and 0.4 to replace the lower limit 0 of conditional expression (5). Also, it is preferably set to any one of 3, 2, 1.4, and 0.95 to replace the upper limit 4 of conditional expression (5).

[0222] The imaging lens preferably satisfies the following conditional expression (6). By preventing the corresponding value of conditional expression (6) from falling below the lower limit, the negative optical power of the front group GF will not become too strong, so it is beneficial for shortening the total length of the optical system. By preventing the corresponding value of conditional expression (6) from exceeding the upper limit, the positive optical power of the front group GF will not become too strong, so it is beneficial for correcting distortion aberration and field curvature.

[0223] -1 < f / fF < 2 (6)

[0224] In order to obtain better characteristics, it is preferably set to any one of -0.8, -0.6, and -0.4 to replace the lower limit -1 of conditional expression (6). Also, it is preferably set to any one of 1.3, 0.7, and 0.18 to replace the upper limit 2 of conditional expression (6).

[0225] When the maximum photographing magnification of the imaging lens is β, the imaging lens preferably satisfies the following conditional expression (7). In addition, in this specification, the photographing magnification in the state of focusing on the nearest object is defined as the maximum photographing magnification. By preventing the corresponding value of conditional expression (7) from falling below the lower limit, it is possible to suppress the narrowing of the range of photographing distances that can be taken, so it is possible to ensure the added value suitable for an imaging lens.

[0226] By preventing the corresponding value of conditional expression (7) from exceeding the upper limit, it is possible to suppress the movement amount of the focusing lens group during focusing, so it is possible to contribute to the miniaturization of the optical system.

[0227] 0.06 < |β| < 0.5 (7)

[0228] In order to obtain better characteristics, it is preferably set to 0.07 or 0.08 instead of the lower limit of 0.06 in conditional expression (7). Also, it is preferably set to 0.35 or 0.21 instead of the upper limit of 0.5 in conditional expression (7).

[0229] The imaging lens preferably satisfies the following conditional expression (8). By preventing the corresponding value of conditional expression (8) from falling below the lower limit, it is beneficial to maintaining high optical performance. By preventing the corresponding value of conditional expression (8) from exceeding the upper limit, it is beneficial to miniaturization of the optical system.

[0230] 3 < TL / (f × tan ωm) < 7 (8)

[0231] In order to obtain better characteristics, it is preferably set to any one of 3.2, 3.4, 3.5, 3.7, and 3.9 instead of the lower limit of 3 in conditional expression (8). Also, it is preferably set to any one of 6.5, 5.9, 5.65, 5.3, and 4.9 instead of the upper limit of 7 in conditional expression (8). For example, the imaging lens more preferably satisfies the following conditional expression (8-1), further preferably satisfies the following conditional expression (8-2), and even more preferably satisfies the following conditional expression (8-3).

[0232] 3.2 < TL / (f × tan ωm) < 6.5 (8-1)

[0233] 3.4 < TL / (f × tan ωm) < 5.9 (8-2)

[0234] 3.5 < TL / (f × tan ωm) < 5.65 (8-3)

[0235] When the open F-number in the state of focusing on an infinitely distant object is set to FNo, the imaging lens preferably satisfies the following conditional expression (9). By preventing the corresponding value of conditional expression (9) from falling below the lower limit, good optical performance can be obtained while easily suppressing an increase in the number of lens elements and suppressing enlargement of the optical system. By preventing the corresponding value of conditional expression (9) from exceeding the upper limit, the viewing angle can be expanded or the open F-number can be reduced, so that it can be applied to a wide range of uses and can become a high-value imaging lens.

[0236] 0.55 < FNo / tan ωm < 2 (9)

[0237] In order to obtain better characteristics, it is preferably set to any one of 0.58, 0.6, 0.62, 0.64, 0.66, 0.68, and 0.7 to replace the lower limit 0.55 of conditional expression (9). Moreover, it is preferably set to any one of 1.9, 1.8, 1.7, 1.62, 1.55, 1.45, and 1.35 to replace the upper limit 2 of conditional expression (9). For example, the imaging lens more preferably satisfies the following conditional expression (9-1), further preferably satisfies the following conditional expression (9-2), and even more preferably satisfies the following conditional expression (9-3).

[0238] 0.64 < FNo / tanωm < 1.62 (9-1)

[0239] 0.66 < FNo / tanωm < 1.55 (9-2)

[0240] 0.7 < FNo / tanωm < 1.35 (9-3)

[0241] When the Abbe number of the first lens based on the d-line is set to νL1, the imaging lens preferably satisfies the following conditional expression (10). By preventing the corresponding value of conditional expression (10) from falling below the lower limit, the Abbe number of the first lens as a negative lens will not become too small, so it is beneficial for correcting longitudinal chromatic aberration well. Optical materials generally tend to have a lower refractive index when the Abbe number increases.

[0242] By preventing the corresponding value of conditional expression (10) from exceeding the upper limit, the Abbe number of the first lens as a negative lens will not become too large, so the refractive index of the first lens will not become too low. Thus, it is beneficial for correcting distortion and field curvature well.

[0243] 20 < νL1 < 95 (10)

[0244] In order to obtain better characteristics, it is preferably set to any one of 21, 22, 23, 24, 26, 28, 30, 31, and 32 to replace the lower limit 20 of conditional expression (10). Moreover, it is preferably set to any one of 83, 75, 69, 64, 62, 59, 56, 52, and 48 to replace the upper limit 95 of conditional expression (10). For example, the imaging lens more preferably satisfies the following conditional expression (10-1), and further preferably satisfies the following conditional expression (10-2).

[0245] 28 < νL1 < 59 (10-1)

[0246] 32 < νL1 < 48 (10-2)

[0247] In a structure where the imaging lens includes two focusing lens groups, the imaging lens preferably satisfies the following conditional expression (16). Here, let the focal length of the first focusing lens group Gf1 be ff1, and let the focal length of the second focusing lens group Gf2 be ff2. By preventing the corresponding value of conditional expression (16) from falling below the lower limit, the optical power of the first focusing lens group Gf1 will not become too strong, so it is easy to correct astigmatism. By preventing the corresponding value of conditional expression (16) from exceeding the upper limit, the optical power of the first focusing lens group Gf1 will not become too weak, so it is easy to correct field curvature.

[0248] 0.2 < |ff1 / ff2| < 5 (16)

[0249] To obtain better characteristics, it is preferably set to 0.6 or 1 instead of the lower limit 0.2 of conditional expression (16). Also, it is preferably set to 3.5 or 2.5 instead of the upper limit 5 of conditional expression (16).

[0250] In a structure where the imaging lens includes two focusing lens groups, the imaging lens preferably satisfies the following conditional expression (17). Here, let the lateral magnification of the first focusing lens group Gf1 in the state of focusing on an infinitely distant object be βf1, and let the lateral magnification of the second focusing lens group Gf2 in the state of focusing on an infinitely distant object be βf2. By preventing the corresponding value of conditional expression (17) from falling below the lower limit, it is easy to correct astigmatism when focusing on the nearest object. By preventing the corresponding value of conditional expression (17) from exceeding the upper limit, it is easy to correct field curvature when focusing on the nearest object.

[0251] 0 < |βf1 / βf2| < 0.6 (17)

[0252] To obtain better characteristics, it is preferably set to 0.02 or 0.04 instead of the lower limit 0 of conditional expression (17). Also, it is preferably set to 0.5 or 0.4 instead of the upper limit 0.6 of conditional expression (17).

[0253] In a structure where the imaging lens includes two focusing lens groups, the imaging lens preferably satisfies the following conditional expression (18). By preventing the corresponding value of conditional expression (18) from falling below the lower limit, it is easy to correct spherical aberration and axial chromatic aberration. By preventing the corresponding value of conditional expression (18) from exceeding the upper limit, it is easy to correct astigmatism, and the movement amount of the first focusing lens group Gf1 from the state of focusing on an infinitely distant object to the state of focusing on the nearest object can be suppressed, which is beneficial for miniaturization.

[0254] 0 < {βf1+(1 / βf1)} -2 <0.25 (18)

[0255] To obtain better characteristics, it is preferably set to 0.05 or 0.1 instead of the lower limit 0 of conditional expression (18).

[0256] Further, it is preferably set to 0.23 or 0.22 instead of the upper limit 0.25 of conditional expression (18).

[0257] In a structure in which the imaging lens includes two focusing lens groups, the imaging lens preferably satisfies the following conditional expression (19). By preventing the corresponding value of conditional expression (19) from falling below the lower limit, it is easy to correct field curvature and astigmatism. By preventing the corresponding value of conditional expression (19) from exceeding the upper limit, it is easy to correct astigmatism, and the movement amount of the second focusing lens group Gf2 from the state of focusing on an infinite object to the state of focusing on the nearest object can be suppressed, which is thus advantageous for miniaturization.

[0258] 0 < {βf2 + (1 / βf2)} -2 <0.25 (19)

[0259] In order to obtain better characteristics, it is preferably set to 0.05 or 0.1 instead of the lower limit 0 of conditional expression (19). Further, it is preferably set to 0.24 or 0.22 instead of the upper limit 0.25 of conditional expression (19).

[0260] In a structure in which the imaging lens includes two focusing lens groups, when the combined focal length of all lenses on the image side of the second focusing lens group Gf2 is set to f2r, the imaging lens preferably satisfies the following conditional expression (20). By preventing the corresponding value of conditional expression (20) from falling below the lower limit, the combined optical power of all lenses on the image side of the second focusing lens group Gf2 does not become too weak, which is thus advantageous for correcting lateral chromatic aberration. By preventing the corresponding value of conditional expression (20) from exceeding the upper limit, the combined optical power of all lenses on the image side of the second focusing lens group Gf2 does not become too strong, which is thus advantageous for correcting distortion and field curvature.

[0261] 0.1 < f / f2r < 2 (20)

[0262] In order to obtain better characteristics, it is preferably set to any one of 0.15, 0.2, and 0.25 instead of the lower limit 0.1 of conditional expression (20). Further, it is preferably set to any one of 1.5, 1, and 0.8 instead of the upper limit 2 of conditional expression (20).

[0263] In a structure where the imaging lens includes two focusing lens groups, when the combined focal length of all the lenses on the object side of the first focusing lens group Gf1 is set to f1f, the imaging lens preferably satisfies the following conditional expression (21). By preventing the corresponding value of the conditional expression (21) from falling below the lower limit, the negative combined optical power of all the lenses on the object side of the first focusing lens group Gf1 does not become too strong. Therefore, it is beneficial for shortening the overall length of the optical system and it is easy to ensure the peripheral light quantity. By preventing the corresponding value of the conditional expression (21) from exceeding the upper limit, the positive combined optical power of all the lenses on the object side of the first focusing lens group Gf1 does not become too strong. Therefore, it is beneficial for correcting distortion aberration and field curvature.

[0264] -3 < f / f1f < 2 (21)

[0265] In order to obtain better characteristics, it is preferable to set it to any one of -2.5, -2, and -1.5 instead of the lower limit -3 of the conditional expression (21). Also, it is preferable to set it to any one of 1.5, 1, and 0.75 instead of the upper limit 2 of the conditional expression (21).

[0266] When the focal length of the first lens is set to fL1 and the focal length of the second lens is set to fL2, the imaging lens preferably satisfies the following conditional expression (22). The front group GF functions as a wide-angle converter. By having the first lens and the second lens share the negative optical power on the object side, it is beneficial for correcting various aberrations such as distortion aberration and field curvature. Regarding the lower limit of the conditional expression (22), since both the first lens and the second lens are negative lenses, 0 < fL1 / fL2 holds. By preventing the corresponding value of the conditional expression (22) from exceeding the upper limit, the negative optical power of the first lens does not become too weak. Therefore, it is easy to correct the longitudinal chromatic aberration well by the first lens.

[0267] 0 < fL1 / fL2 < 5.5 (22)

[0268] In order to obtain better characteristics, it is preferable to set it to 0.1 instead of the lower limit 0 of the conditional expression (22). In such a configuration, the negative optical power of the second lens does not become too weak. Therefore, it is beneficial for correcting distortion aberration and field curvature. In order to obtain further better characteristics, it is preferable to set it to 0.2 or 0.3 instead of the lower limit 0 of the conditional expression (22). Also, in order to obtain better characteristics, it is preferable to set it to any one of 4, 2.5, and 1.5 instead of the upper limit 5.5 of the conditional expression (22).

[0269] The imaging lens preferably satisfies the following conditional expression (23). As described above, the first lens is a lens that shares the role of the wide-angle converter. The conditional expression (23) defines a preferred range to widen the viewing angle of the first lens and perform good aberration correction. By preventing the corresponding value of the conditional expression (23) from falling below the lower limit, the negative optical power of the first lens does not become too weak relative to the optical power of the entire system. Therefore, in the front group GF that plays the role of the wide-angle converter, the first lens and the second lens can appropriately share the negative optical power. As a result, it is beneficial to correct various aberrations such as distortion aberration and field curvature. By preventing the corresponding value of the conditional expression (23) from exceeding the upper limit, the optical power of the first lens does not become too strong relative to the optical power of the entire system. Therefore, it is easy to correct the lateral chromatic aberration well through the first lens.

[0270] -8 < fL1 / f < -0.5 (23)

[0271] To obtain better characteristics, it is preferable to set it to any one of -7, -6, and -5 instead of the lower limit -8 of the conditional expression (23). Also, it is preferable to set it to any one of -1, -1.3, and -1.5 instead of the upper limit -0.5 of the conditional expression (23).

[0272] The imaging lens preferably satisfies the following conditional expression (24). Here, let the paraxial curvature radius of the object side surface of the first lens be RL1f. Let the paraxial curvature radius of the image side surface of the first lens be RL1r. The conditional expression (24) defines the shape factor of the first lens. By preventing the corresponding value of the conditional expression (24) from falling below the lower limit, it is easy to correct astigmatism well. By preventing the corresponding value of the conditional expression (24) from exceeding the upper limit, it is easy to correct spherical aberration well. Also, by preventing the corresponding value of the conditional expression (24) from exceeding the upper limit, the optical power of the lens does not become too weak, so it is easy to achieve wide-angleization.

[0273] -2.5 < (RL1r - RL1f) / (RL1r + RL1f) < -0.1 (24)

[0274] To obtain better characteristics, it is preferable to set it to -2 or -1.5 instead of the lower limit -2.5 of the conditional expression (24). Also, it is preferable to set it to -0.2 or -0.3 instead of the upper limit -0.1 of the conditional expression (24).

[0275] The imaging lens preferably satisfies the following conditional expression (25). Here, the paraxial curvature radius of the object-side surface of the second lens is denoted as RL2f, and the paraxial curvature radius of the image-side surface of the second lens is denoted as RL2r. Conditional expression (25) defines the shape factor of the second lens. By preventing the corresponding value of conditional expression (25) from falling below the lower limit, it is easy to correct astigmatism well. By preventing the corresponding value of conditional expression (25) from exceeding the upper limit, it is easy to correct spherical aberration well. Also, by preventing the corresponding value of conditional expression (25) from exceeding the upper limit, the optical power of the lens does not become too weak, so it is easy to achieve wide-angleization.

[0276] -1.5 < (RL2r - RL2f) / (RL2r + RL2f) < -0.05 (25)

[0277] To obtain better characteristics, it is preferably set to -1 or -0.7 instead of the lower limit -1.5 of conditional expression (25). Also, it is preferably set to -0.09 or -0.15 instead of the upper limit -0.05 of conditional expression (25).

[0278] In the imaging lens of the present invention, it can be configured such that a third lens as a negative lens is disposed adjacent to the image side of the second lens, and a fourth lens as a positive lens is disposed adjacent to the image side of the third lens. In the structure where the imaging lens includes the above-described third lens and fourth lens, when the focal length of the third lens is denoted as fL3 and the focal length of the fourth lens is denoted as fL4, the imaging lens preferably satisfies the following conditional expression (26). By preventing the corresponding value of conditional expression (26) from falling below the lower limit, the negative optical power of the third lens does not become too weak, so it is easy to correct various aberrations such as distortion aberration and field curvature. Regarding the upper limit of conditional expression (26), depending on the signs of the optical powers of the third lens and the fourth lens, fL3 / fL4 < 0.

[0279] -8 < fL3 / fL4 < 0 (26)

[0280] To obtain better characteristics, it is preferably set to -5.5 or -3.5 instead of the lower limit -8 of conditional expression (26). Also, it is preferably set to -0.03 instead of the upper limit 0 of conditional expression (26). In such a configuration, the positive optical power of the fourth lens does not become too weak, so it is easy to correct spherical aberration. To obtain further better characteristics, it is preferably set to -0.1 or -0.15 instead of the upper limit 0 of conditional expression (26).

[0281] The imaging lens preferably satisfies the following conditional expression (27). Here, the paraxial curvature radius of the object side surface of the lens closest to the image side of the imaging lens is denoted as R Lef. The paraxial curvature radius of the image side surface of the lens closest to the image side of the imaging lens is denoted as R ler. By preventing the corresponding value of conditional expression (27) from falling below the lower limit, it is easy to shorten the back focal length, which is thus beneficial for miniaturization of the optical system. By preventing the corresponding value of conditional expression (27) from exceeding the upper limit, it is easy to correct various aberrations such as field curvature well.

[0282] 0.4 < (R ler - R Lef) / (R ler + R Lef) < 5.5 (27)

[0283] To obtain better characteristics, it is preferably set to 0.5 or 0.6 instead of the lower limit 0.4 of conditional expression (27). Also, it is preferably set to 4.2 or 3.3 instead of the upper limit 5.5 of conditional expression (27).

[0284] At least one of the object side surface and the image side surface of the first lens may be configured as an aspherical surface. In the structure where at least one of the object side surface and the image side surface of the first lens is an aspherical surface, the imaging lens preferably satisfies the following conditional expression (28). Here, the paraxial curvature radius of the object side surface of the first lens is denoted as R L1f. The paraxial curvature radius of the image side surface of the first lens is denoted as R L1r. The curvature radius at the position of the maximum effective diameter of the object side surface of the first lens is denoted as R yL1f. The curvature radius at the position of the maximum effective diameter of the image side surface of the first lens is denoted as R yL1r. By preventing the corresponding value of conditional expression (28) from falling below the lower limit, the optical power on the peripheral side of the lens will not become too strong, so that overcorrection of field curvature can be suppressed. By preventing the corresponding value of conditional expression (28) from exceeding the upper limit, the optical power on the peripheral side of the lens will not become too weak, which is thus beneficial for correcting field curvature.

[0285] 0.5 < (1 / R L1f - 1 / R L1r) / (1 / R yL1f - 1 / R yL1r) < 7 (28)

[0286] To obtain better characteristics, it is preferably set to any one of 0.7, 0.9, and 1.1 instead of the lower limit 0.5 of conditional expression (28). Also, it is preferably set to any one of 5.7, 4.5, and 3.5 instead of the upper limit 7 of conditional expression (28).

[0287] As an illustrative figure, in Figure 3 an example of the position Px of the maximum effective diameter is shown. In Figure 3 the left side is the object side and the right side is the image side. In Figure 3 the on-axis beam Xa and the off-axis beam Xb passing through the lens Lx are shown. In Figure 3In the example, the upper-side ray of the off-axis beam Xb, i.e., ray Xb1, is the ray passing through the outermost side. In this specification, the distance from the intersection of the ray passing through the outermost side among the rays incident on the lens surface from the object side and exiting toward the image side to the optical axis Z is defined as the "effective radius" of the lens surface. The "outer side" described herein refers to the radially outer side centered on the optical axis Z, i.e., the side away from the optical axis Z. In Figure 3 the example, the distance from the intersection of the object-side surface of the lens Lx and the ray Xb1 to the optical axis Z becomes the effective radius Effx of the object-side surface of the lens Lx. And the position of the intersection of the ray passing through the outermost side and the lens surface becomes the position Px of the maximum effective diameter. In addition, in Figure 3 the example, the upper-side ray of the off-axis beam Xb is the ray passing through the outermost side, but which ray becomes the ray passing through the outermost side varies depending on the optical system.

[0288] The front group GF can be configured to include at least one positive lens. In the structure where the front group GF includes at least one positive lens, the imaging lens preferably satisfies the following conditional expression (29). Here, the focal length of the positive lens with the strongest optical power among the positive lenses included in the front group GF is set as fFp. By preventing the corresponding value of the conditional expression (29) from falling below the lower limit, it is easy to shorten the flange distance and miniaturize. By preventing the corresponding value of the conditional expression (28) from exceeding the upper limit, the optical power of the positive lens in the front group GF will not become too strong, so it is easy to correct various aberrations such as spherical aberration.

[0289] 0.1 < f / fFp < 3 (29)

[0290] To obtain better characteristics, it is preferably set to 0.2 or 0.3 instead of the lower limit 0.1 of the conditional expression (29). And it is preferably set to 2 or 1.5 instead of the upper limit 3 of the conditional expression (29).

[0291] The rear group GR can be configured to include at least one positive lens. In the structure where the rear group GR includes at least one positive lens, the imaging lens preferably satisfies the following conditional expression (30). Here, the focal length of the positive lens with the strongest optical power among the positive lenses included in the rear group GR is set as fRp. By preventing the corresponding value of the conditional expression (30) from falling below the lower limit, the optical power of the positive lens in the rear group GR will not become too weak, so it is easy to correct various aberrations such as spherical aberration. By preventing the corresponding value of the conditional expression (30) from exceeding the upper limit, it is easy to shorten the flange distance and miniaturize.

[0292] 0.3 < fR / fRp < 5 (30)

[0293] To obtain better characteristics, it is preferably set to 0.6 or 0.8 instead of the lower limit 0.3 of the conditional expression (30). And it is preferably set to 4 or 3.2 instead of the upper limit 5 of the conditional expression (30).

[0294] In a structure where the rear group GR includes a cemented lens formed by sequentially cementing a positive lens with its convex surface facing the object side and a negative lens from the object side, the imaging lens preferably satisfies the following conditional expression (31). Here, the Abbe number of the positive lens of the cemented lens of the rear group GR with respect to the d-line is designated as νRp. The Abbe number of the negative lens of the cemented lens of the rear group GR with respect to the d-line is designated as νRn. By preventing the corresponding value of conditional expression (31) from falling below the lower limit, it is easy to correct the longitudinal chromatic aberration. By preventing the corresponding value of conditional expression (31) from exceeding the upper limit, overcorrection of the axial chromatic aberration can be suppressed.

[0295] 10 < νRp - νRn < 75 (31)

[0296] To obtain better characteristics, it is preferable to set it to 20 or 25 instead of the lower limit of 10 in conditional expression (31).

[0297] Also, it is preferable to set it to 70 or 68 instead of the upper limit of 75 in conditional expression (31).

[0298] In a structure where the rear group GR includes a cemented lens formed by sequentially cementing a positive lens with its convex surface facing the object side and a negative lens from the object side, the imaging lens preferably satisfies the following conditional expression (32). Here, the refractive index of the positive lens of the cemented lens of the rear group GR with respect to the d-line is designated as NRp. The refractive index of the negative lens of the cemented lens of the rear group GR with respect to the d-line is designated as NRn. By preventing the corresponding value of conditional expression (32) from falling below the lower limit, it is easy to correct the longitudinal chromatic aberration. By preventing the corresponding value of conditional expression (32) from exceeding the upper limit, overcorrection of the axial chromatic aberration can be suppressed.

[0299] 0.2 < NRp - NRn < 0.9 (32)

[0300] To obtain better characteristics, it is preferable to set it to 0.3 or 0.35 instead of the lower limit of 0.2 in conditional expression (32). Also, it is preferable to set it to 0.7 or 0.6 instead of the upper limit of 0.9 in conditional expression (32).

[0301] When an LFe lens, which is a positive lens, is disposed on the image side closest to the front group GF, at least one of the object side surface and the image side surface of the LFe lens can be an aspherical surface. In a structure in which an LFe lens is disposed on the image side closest to the front group GF and at least one of the object side surface and the image side surface of the LFe lens is an aspherical surface, the imaging lens preferably satisfies the following conditional expression (33). Here, the paraxial curvature radius of the object side surface of the LFe lens is denoted as RcLFef. The paraxial curvature radius of the image side surface of the LFe lens is denoted as RcLFer. The curvature radius at the position of the maximum effective diameter of the object side surface of the LFe lens is denoted as RyLFef. The curvature radius at the position of the maximum effective diameter of the image side surface of the LFe lens is denoted as RyLFer. By preventing the corresponding value of the conditional expression (33) from falling below the lower limit, the optical power on the peripheral side of the lens does not become too strong, which is thus beneficial for correcting field curvature and distortion aberration. By preventing the corresponding value of the conditional expression (33) from exceeding the upper limit, the optical power on the peripheral side of the lens does not become too weak, which is thus beneficial for suppressing astigmatism.

[0302] 0.5 < (1 / RcLFef - 1 / RcLFer) / (1 / RyLFef - 1 / RyLFer) < 7 (33)

[0303] In order to obtain better characteristics, it is preferably set to any one of 0.7, 0.9, and 1.1 instead of the lower limit 0.5 of the conditional expression (33). Moreover, it is preferably set to any one of 5.7, 4.5, and 3.5 instead of the upper limit 7 of the conditional expression (33).

[0304] In a structure in which an LFe lens, which is a positive lens, is disposed on the image side closest to the front group GF, the imaging lens preferably satisfies the following conditional expression (34). The conditional expression (34) defines the shape factor of the LFe lens. By preventing the corresponding value of the conditional expression (34) from falling below the lower limit, it is easy to correct astigmatism well. By preventing the corresponding value of the conditional expression (34) from exceeding the upper limit, it is easy to correct spherical aberration well.

[0305] -4 < (RcLFef - RcLFer) / (RcLFef + RcLFer) < 10 (34)

[0306] In order to obtain better characteristics, it is preferably set to -3.5 or -3 instead of the lower limit -4 of the conditional expression (34). Moreover, it is preferably set to 5 or 3 instead of the upper limit 10 of the conditional expression (34).

[0307] In a structure in which an LFe lens, which is a positive lens, is disposed on the image side closest to the front group GF, when the Abbe number of the LFe lens based on the d line is denoted as νLFe, the imaging lens preferably satisfies the following conditional expression (35).

[0308] By preventing the corresponding value of conditional expression (35) from falling below the lower limit, color aberration can be easily corrected. By preventing the corresponding value of conditional expression (35) from exceeding the upper limit, materials with high availability can be used, and thus it is easy to achieve good correction of various aberrations other than color aberration.

[0309] 15 < νLFe < 90 (35)

[0310] To obtain better characteristics, it is preferable to set it to 19 or 23 instead of the lower limit of 15 of conditional expression (35). Also, it is preferable to set it to 80 or 72 instead of the upper limit of 90 of conditional expression (35).

[0311] When the central thickness of the first lens is D1, the imaging lens preferably satisfies the following conditional expression (36). As an example, Figure 2 shows the central thickness D1. By preventing the corresponding value of conditional expression (36) from falling below the lower limit, the central thickness D1 of the first lens will not become too thin, and thus the strength against external impacts on the optical system can be improved. By preventing the corresponding value of conditional expression (36) from exceeding the upper limit, the central thickness D1 of the first lens will not become too thick, and thus it can contribute to the light weight of the optical system.

[0312] 0.007 < D1 / TL < 0.1 (36)

[0313] To obtain better characteristics, it is preferable to set it to 0.01 or 0.011 instead of the lower limit of 0.007 of conditional expression (36). Also, it is preferable to set it to 0.08 or 0.06 instead of the upper limit of 0.1 of conditional expression (36).

[0314] When the thickness of the first lens in the optical axis direction at the height of the maximum effective diameter of the image-side surface of the first lens is DH1, the imaging lens preferably satisfies the following conditional expression (37). The "height of the maximum effective diameter" mentioned here refers to the distance from the optical axis Z to the position of the maximum effective diameter. As an example, Figure 2 shows the above thickness DH1. Conditional expression (37) is an expression related to the ratio of the wall thickness on the optical axis of the first lens to the wall thickness outside the optical axis. By preventing the corresponding value of conditional expression (37) from falling below the lower limit, the wall thickness ratio of the first lens will not become too small, and thus it is easy to correct astigmatism and distortion aberration. By preventing the corresponding value of conditional expression (37) from exceeding the upper limit, the wall thickness ratio of the first lens will not become too large, and thus it is easy to manufacture the first lens.

[0315] 2 < DH1 / D1 < 10 (37)

[0316] To obtain better characteristics, it is preferable to set it to 2.4 instead of the lower limit of 2 of conditional expression (37). Also, it is preferable to set it to 9 instead of the upper limit of 10 of conditional expression (37).

[0317] When the Abbe number based on the d-line of the lens closest to the image side of the imaging lens is set as νLe, the imaging lens preferably satisfies the following conditional expression (38). By preventing the corresponding value of the conditional expression (38) from falling below the lower limit, it becomes easy to correct chromatic aberration. By preventing the corresponding value of the conditional expression (38) from exceeding the upper limit, materials with high availability can be used, and thus it becomes easy to achieve good correction of various aberrations other than chromatic aberration.

[0318] 30 < νLe < 95 (38)

[0319] In order to obtain better characteristics, it is preferable to set it to 40 or 45 instead of the lower limit 30 of the conditional expression (38). Also, it is preferable to set it to 92 or 90 instead of the upper limit 95 of the conditional expression (38).

[0320] When the effective radius of the object-side surface of the first lens is set as EL1, the imaging lens preferably satisfies the following conditional expression (39). By preventing the corresponding value of the conditional expression (39) from falling below the lower limit, it is beneficial to ensure sufficient peripheral light quantity. By preventing the corresponding value of the conditional expression (39) from exceeding the upper limit, it is possible to suppress the increase in the diameter of the first lens, and thus it is possible to achieve miniaturization and lightening.

[0321] Moreover, this can contribute to improving the degree of freedom in the arrangement of the mechanism for holding the lens.

[0322] 0.7 < EL1 / (f × tan ωm) < 2 (39)

[0323] In order to obtain better characteristics, it is preferable to set it to 0.8 or 0.9 instead of the lower limit 0.7 of the conditional expression (39). Also, it is preferable to set it to 1.7 or 1.5 instead of the upper limit 2 of the conditional expression (39).

[0324] The imaging lens preferably includes at least one Ls lens on the image side of the second lens and satisfying the following conditional expressions (40), (41), (42), and (43). Here, the refractive index of the Ls lens with respect to the d-line is set as NLs. The Abbe number based on the d-line of the Ls lens is set as νLs. The partial dispersion ratio between the g-line and the F-line of the Ls lens is set as θgFLs. In Figure 1 the example of, the lens L13 corresponds to the Ls lens.

[0325] 0.005 < NLs - (2.015 - 0.0068 × νLs) < 0.15 (40)

[0326] 49.8 < νLs < 65 (41)

[0327] 0.543 < θgFLs < 0.58 (42)

[0328] -0.011 < θgFLs - (0.6418 - 0.00168 × νLs) < 0.035 (43)

[0329] By preventing the corresponding value of conditional expression (40) from falling below the lower limit, it is easy to correct chromatic aberration. By preventing the corresponding value of conditional expression (40) from exceeding the upper limit, it is easy to simultaneously and favorably correct spherical aberration and chromatic aberration.

[0330] To obtain better characteristics, it is preferable to set it to any one of 0.015, 0.025, 0.03, and 0.035 instead of the lower limit 0.005 of conditional expression (40). Also, it is preferable to set it to any one of 0.14, 0.13, 0.12, and 0.116 instead of the upper limit 0.15 of conditional expression (40).

[0331] By preventing the corresponding value of conditional expression (41) from falling below the lower limit, it is easy to correct chromatic aberration. By preventing the corresponding value of conditional expression (41) from exceeding the upper limit, materials with high availability can be used, so it is easy to achieve favorable correction of each aberration other than chromatic aberration.

[0332] To obtain better characteristics, it is preferable to set it to 50.1 or 50.2 instead of the lower limit 49.8 of conditional expression (41). Also, it is preferable to set it to 63 or 59 instead of the upper limit 65 of conditional expression (41).

[0333] By preventing the corresponding value of conditional expression (42) from falling below the lower limit, it is easy to correct chromatic aberration. By preventing the corresponding value of conditional expression (42) from exceeding the upper limit, materials with high availability can be used, so it is easy to achieve favorable correction of each aberration other than chromatic aberration.

[0334] To obtain better characteristics, it is preferable to set it to 0.544 or 0.5445 instead of the lower limit 0.543 of conditional expression (42). Also, it is preferable to set it to 0.57 or 0.563 instead of the upper limit 0.58 of conditional expression (42).

[0335] By preventing the corresponding value of conditional expression (43) from falling below the lower limit, it is easy to correct chromatic aberration. By preventing the corresponding value of conditional expression (43) from exceeding the upper limit, materials with high availability can be used, so it is easy to achieve favorable correction of each aberration other than chromatic aberration.

[0336] To obtain better characteristics, it is preferable to set it to any one of -0.01, -0.009, and -0.008 instead of the lower limit -0.011 of conditional expression (43). Also, it is preferable to set it to any one of 0.025, 0.015, and 0.005 instead of the upper limit 0.035 of conditional expression (43).

[0337] In addition, Figure 1The example shown is one example, and various modifications can be made without departing from the gist of the technology of the present invention. For example, the number of lenses included in the front group GF, the rear group GR, and the focusing lens group can be set to a number different from that of the Figure 1 example.

[0338] In Figure 1 the example, the first focusing lens group Gf1 and the second focusing lens group Gf2 are arranged continuously, but in the imaging lens of the present invention, the first focusing lens group Gf1 and the second focusing lens group Gf2 may be arranged discontinuously.

[0339] The focusing lens group can be arranged at a position different from that of the Figure 1 example. For example, it can be configured such that the first focusing lens group Gf1 is arranged in the front group GF and the second focusing lens group Gf2 is arranged in the rear group GR. By arranging one focusing lens group in each of the front group GF and the rear group GR, it is easy to suppress the aberration variation during focusing, and compared with the case where it is not configured like this, the optical power of each focusing lens group can be enhanced. As a result, the movement amount of each focusing lens group during focusing can be further suppressed, which is therefore beneficial for high-speed focusing.

[0340] In Figure 1 the example, when focusing from an infinite object to the nearest object, one of the first focusing lens group Gf1 and the second focusing lens group Gf2 moves toward the image side and the other moves toward the object side. However, in the imaging lens of the present invention, when focusing from an infinite object to the nearest object, it can be configured such that both the first focusing lens group Gf1 and the second focusing lens group Gf2 move toward the image side, or it can also be configured such that both of them move toward the object side.

[0341] And Figure 1 the imaging lens of the example has two focusing lens groups, but the imaging lens of the present invention can also be configured to have only one focusing lens group. In this way, when the lens group that moves during focusing is only one, the mechanism can be simplified.

[0342] When the imaging lens includes only one focusing lens group, the focusing lens group can be configured to be arranged in the rear group GR. By arranging the focusing lens group in the rear group GR, it is beneficial for miniaturizing the focusing lens group.

[0343] In the structure where the imaging lens includes only one focusing lens group and the focusing lens group is arranged in the rear group GR, the imaging lens preferably satisfies the following conditional expression (11). Here, the focal length of the focusing lens group is set to ff. By preventing the corresponding value of the conditional expression (11) from falling below the lower limit, the optical power of the focusing lens group will not become too weak, so the movement amount of the focusing lens group during focusing can be suppressed. By preventing the corresponding value of the conditional expression (11) from exceeding the upper limit, it is easy to suppress the aberration variation during focusing.

[0344] 0.05 < |f / ff| < 0.9 (11)

[0345] In order to obtain better characteristics, it is preferably set to any one of 0.09, 0.12, and 0.15 to replace the lower limit 0.05 of conditional expression (11). Further, it is preferably set to any one of 0.75, 0.65, and 0.55 to replace the upper limit 0.9 of conditional expression (11).

[0346] In a structure where the imaging lens includes only one focusing lens group and this focusing lens group is disposed in the rear group GR, the imaging lens preferably satisfies the following conditional expression (12).

[0347] By preventing the corresponding value of conditional expression (12) from falling below the lower limit, the optical power of the focusing lens group will not become too weak, so that the movement amount of the focusing lens group during focusing can be suppressed. By preventing the corresponding value of conditional expression (12) from exceeding the upper limit, it is easy to suppress the aberration variation during focusing.

[0348] 0.1 < |TL / ff| < 6 (12)

[0349] In order to obtain better characteristics, it is preferably set to any one of 0.45, 0.75, and 1 to replace the lower limit 0.1 of conditional expression (12). Further, it is preferably set to any one of 4.5, 4, and 3.5 to replace the upper limit 6 of conditional expression (12).

[0350] In a structure where the imaging lens includes only one focusing lens group and this focusing lens group is disposed in the rear group GR, the imaging lens preferably satisfies the following conditional expression (13). Here, the combined focal length of all lenses on the image side with respect to the focusing lens group is set to ff_r. By preventing the corresponding value of conditional expression (13) from falling below the lower limit, the combined optical power of all lenses on the image side with respect to the focusing lens group will not become too weak, which is beneficial for correcting the lateral chromatic aberration. By preventing the corresponding value of conditional expression (13) from exceeding the upper limit, the combined optical power of all lenses on the image side with respect to the focusing lens group will not become too strong, which is beneficial for correcting the distortion aberration and the field curvature.

[0351] 0.05 < f / ff_r < 1.5 (13)

[0352] In order to obtain better characteristics, it is preferably set to any one of 0.08, 0.1, and 0.12 to replace the lower limit 0.05 of conditional expression (13). Further, it is preferably set to any one of 1.2, 0.9, and 0.7 to replace the upper limit 1.5 of conditional expression (13).

[0353] In a structure where the imaging lens includes only one focusing lens group and this focusing lens group is arranged in the rear group GR, the imaging lens preferably satisfies the following conditional expression (14). Here, the combined focal length of all the lenses on the object side of the focusing lens group is set as ff_f. By preventing the corresponding value of conditional expression (14) from falling below the lower limit, the negative combined optical power of all the lenses on the object side of the focusing lens group will not become too strong, so it is beneficial to shorten the total length of the optical system and it is easy to ensure the peripheral light quantity. By preventing the corresponding value of conditional expression (14) from exceeding the upper limit, the negative combined optical power of all the lenses on the object side of the focusing lens group will not become too weak, so it is beneficial to correct distortion aberration and field curvature.

[0354] -3 < f / ff_f < 0 (14)

[0355] In order to obtain better characteristics, it is preferable to set it as any one of -2.5, -2 and -1.5 to replace the lower limit -3 of conditional expression (14). And, it is preferable to set it as any one of -0.03, -0.05 and -0.07 to replace the upper limit 0 of conditional expression (14).

[0356] In the case where the imaging lens includes only one focusing lens group, this focusing lens group can be configured to be arranged in the front group GF. By arranging the focusing lens group in the front group GF, the number of lenses that move during focusing can be further reduced, so it is beneficial to high-speed focusing.

[0357] And, in Figure 1 the example of, during focusing, the aperture stop St is fixed relative to the image plane Sim, but in the imaging lens of the present invention, the focusing lens group can be configured to include the aperture stop St, and during focusing, the aperture stop St moves along the optical axis Z. In the case of such a configuration, it is beneficial to suppress the aberration variation during focusing. In the case where the focusing lens group includes the aperture stop St and at least one lens, it is preferable that during focusing, all the lenses included in the focusing lens group move integrally with the aperture stop St.

[0358] In the case of such a configuration, the mechanism can be simplified. In addition, "move integrally" means moving the same amount in the same direction simultaneously.

[0359] In a structure where the imaging lens includes only one focusing lens group, the focusing lens group includes an aperture stop St, and during focusing, the aperture stop St moves along the optical axis Z, the imaging lens preferably satisfies the following conditional expression (15). Here, the focal length of the focusing lens group including the aperture stop St that moves during focusing is set as ffs. By preventing the corresponding value of the conditional expression (15) from falling below the lower limit, the optical power of the focusing lens group including the aperture stop St that moves during focusing does not become too weak, and thus the amount of movement of the focusing lens group during focusing can be suppressed. By preventing the corresponding value of the conditional expression (15) from exceeding the upper limit, it is easy to suppress aberration variation during focusing.

[0360] 0.1 < f / ffs < 0.5 (15)

[0361] In order to obtain better characteristics, it is preferably set to any one of 0.13, 0.16, 0.18, and 0.2 instead of the lower limit 0.1 of the conditional expression (15). Also, it is preferably set to any one of 0.47, 0.44, 0.42, and 0.4 instead of the upper limit 0.5 of the conditional expression (15).

[0362] Including the structure related to the conditional expression, the above-mentioned preferred structures and available structures can be arbitrarily combined, and it is preferably selectively adopted appropriately according to the required specifications.

[0363] As an example, a preferred mode of the imaging lens of the present invention includes a front group GF, an aperture stop St, and a rear group GR in order from the object side to the image side. The front group GF continuously includes, in order from the object side to the image side, a first lens that is a negative lens with the concave surface facing the image side and a second lens that is a negative lens with the concave surface facing the image side. Two or fewer focusing lens groups are arranged on the image side of the second lens. During focusing, the two or fewer focusing lens groups move along the optical axis Z, and the lenses other than the two or fewer focusing lens groups are fixed with respect to the image plane Sim and satisfy the above-mentioned conditional expression (1).

[0364] Next, embodiments of the imaging lens of the present invention will be described with reference to the accompanying drawings. In addition, the reference signs on the lenses in the cross-sectional views of the respective embodiments are used independently in each embodiment to avoid complication of the description and the drawings due to an increase in the number of digits of the reference signs. Therefore, even if the same reference sign is marked in the drawings of different embodiments, it is not necessarily the same structure.

[0365] [Embodiment 1]

[0366] In Figure 1A cross-sectional view showing the structure of the imaging lens of Embodiment 1 is shown. The illustration method and structure are as described above, so a part of the repeated description is omitted here. The imaging lens of Embodiment 1 includes, in order from the object side to the image side, a front group GF having a positive optical power, an aperture stop St, and a rear group GR having a positive optical power. The front group GF includes a first focusing lens group Gf1 having a positive optical power and a second focusing lens group Gf2 having a positive optical power.

[0367] The front group GF includes, in order from the object side to the image side, seven lenses L11 to L17. The rear group GR includes, in order from the object side to the image side, six lenses L21 to L26. The first focusing lens group Gf1 includes the lens L15. The second focusing lens group Gf2 includes the lenses L16 and L17. When focusing from an infinite object to the nearest object, the first focusing lens group Gf1 moves toward the image side, the second focusing lens group Gf2 moves toward the object side, and the other lenses and the aperture stop St are fixed with respect to the image plane Sim.

[0368] Regarding the imaging lens of Embodiment 1, the basic lens data is shown in Table 1, the specifications are shown in Table 2, the variable surface intervals are shown in Table 3, and the aspherical coefficients are shown in Table 4.

[0369] The basic lens data table is recorded as follows. In the Sn column, the surface number is shown when the surface closest to the object side is set as the first surface and the numbers are incremented one by one toward the image side. In the R column, the curvature radius of each surface is shown. In the D column, the axial surface interval between each surface and the surface adjacent to it on the image side is shown. In the Nd column, the refractive index of each component with respect to the d line is shown. In the νd column, the Abbe number of each component based on the d line is shown. In the θgF column, the partial dispersion ratio between the g line and the F line of each component is shown. In the leftmost column of the lens row corresponding to each focusing lens group, the reference symbol of that focusing lens group is shown. For example, "Gf1" in the left column of the 9th to 10th surfaces in Table 1 indicates that the 9th to 10th surfaces correspond to the first focusing lens group Gf1.

[0370] In the table of the basic lens data, the sign of the curvature radius of the surface with the convex shape facing the object side is set to positive, and the sign of the curvature radius of the surface with the convex shape facing the image side is set to negative. In the surface number column corresponding to the aperture stop St, the surface number and the term "(St)" are entered. The value in the bottom row of the D column in the table is the interval between the surface closest to the image side in the table and the image plane Sim. Regarding the variable surface interval during focusing, the notation DD is used, and the surface number on the object side of the interval is marked after DD and entered in the column of the surface interval.

[0371] In Table 2, the focal length f, the back focal length Bf, the open F value FNo, and the maximum full view angle 2ωm are shown based on the d line. The [°] in the maximum full view angle column indicates that the unit is degrees. The values in the state of focusing on an infinite object are shown in Table 2.

[0372] The variable surface interval during focusing is shown in Table 3. In Table 3, the surface interval in the state of focusing on an object at infinity is shown in the "Infinity" column. The absolute value of the photographic magnification in the state of focusing on the nearest object, that is, the absolute value of the maximum photographic magnification, is shown after "|β| =", and the variable surface interval in the state of focusing on the nearest object is shown in this column.

[0373] In the basic lens data, the surface numbers of the aspherical surfaces are marked with an asterisk, and the values of the paraxial curvature radii are recorded in the column of the curvature radii of the aspherical surfaces. In Table 4, the surface numbers of the aspherical surfaces are shown in the Sn row, and the values of the aspherical coefficients for each aspherical surface are shown in the KA and Am rows. In addition, m in Am is an integer of 3 or more and varies according to the surface. For example, in the first surface of Example 1, m = 4, 6, 8, 10, 12, 14, 16, 18, 20. "E±n" (n: integer) of the values of the aspherical coefficients in Table 4 means "×10 ±n ". KA and Am are the aspherical coefficients in the aspherical formula represented by the following formula.

[0374] Zd = C×h 2 / {1+(1 - KA×C 2 ×h 2 ) 1 / 2}+∑Am×h m

[0375] where

[0376] Zd: Aspherical depth (the length of the perpendicular line dropped from a point on the aspherical surface at height h to the plane perpendicular to the optical axis Z that is tangent to the vertex of the aspherical surface)

[0377] h: Height (the distance from the optical axis Z to the lens surface)

[0378] C: Reciprocal of the paraxial curvature radius

[0379] KA, Am: Aspherical coefficients

[0380] , and ∑ in the aspherical formula represents the sum related to m.

[0381] In the data of each table, degrees are used as the unit of angle, and mm (millimeters) are used as the unit of length. The optical system can be used with an enlarged scale or a reduced scale, so other appropriate units can also be used. And the values rounded to a preset number of digits are recorded in the following tables.

[0382] [Table 1]

[0383] Example 1

[0384]

[0385]

[0386] [Table 2]

[0387] Example 1

[0388] f 14.42 Bf 13.20 FNo. 1.80 2ωm[°] 118.0

[0389] [Table 3] Example 1

[0390] Infinity |β|＝0.2 DD8 4.2975 7.6322 DD10 10.2534 0.9629 DD13 2.2498 8.2056

[0391] [Table 4]

[0392] Example 1

[0393] Sn 1 2 7 8 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 2.4152757E-05 2.7368644E-05 -2.9530383E-05 -1.7635880E-05 A6 -7.5600978E-08 -6.7314149E-08 -1.2205910E-07 -1.3365112E-07 A8 1.5031819E-10 6.4296363E-11 -3.4061236E-10 -2.0551473E-10 A10 -1.5019009E-13 2.4628738E-14 1.1296523E-13 1.1805332E-12 A12 5.5169987E-17 1.4089712E-16 4.9802945E-15 2.1135078E-15 A14 4.8801502E-20 -1.0848143E-19 3.6144929E-18 -4.4642932E-18 A16 -8.3497753E-23 1.6698667E-21 —1.9578473E-19 1.7124397E-20 A18 4.6444591E-26 —3.7271422E-24 9.2341759E-22 —2.7958951E-22 A20 —5.6105191E-30 —2.7510099E-27 —1.6020906E-24 6.2506543E-25

[0394] Sn 15 16 KA 1.0000000E+00 1.0000000E+00 A4 9.6710373E-05 2.9970972E-05 A6 —4.6471658E-07 —4.9500126E-07 A8 1.9848819E-09 1.8774237E-09 A10 —4.6044444E-12 —5.2333649E-12

[0395] Sn 21 22 KA 1.4946577E-06 0.0000000E+00 A4 4.9178462E-05 9.5999300E-05 A6 2.9130952E-07 3.1239799E-07 A8 —8.7540418E-10 6.4707724E-10 A10 —9.1007422E-14 —2.0982371E-11 A12 —3.4710088E-13 —9.3191278E-14 A14 3.7634616E-15 1.3648872E-15 A16 —1.5045984E-17 —3.2983172E-18 A18 2.1601484E-20 —8.5836739E-22

[0396] In Figure 4 the aberration diagrams of the imaging lens of Example 1 are shown. In Figure 4 from left to right, spherical aberration, astigmatism, distortion aberration, and lateral chromatic aberration are shown. In Figure 4 in the upper part marked with "infinity", the aberration diagrams of the state focused on an object at infinity are shown, and in the lower part marked with "|β| = 0.2", the aberration diagrams of the state focused on the nearest object are shown. In the spherical aberration diagram, the aberrations of the d-line, C-line, and F-line are shown by solid lines, long dashed lines, and short dashed lines, respectively. In the astigmatism diagram, the aberration of the d-line in the sagittal direction is shown by a solid line, and the aberration of the d-line in the meridional direction is shown by a short dashed line. In the distortion aberration diagram, the aberration of the d-line is shown by a solid line. In the lateral chromatic aberration diagram, the aberrations of the C-line and F-line are shown by long dashed lines and short dashed lines, respectively. In the spherical aberration diagram, the value of the open F-number is shown after "FNo. =". In the other aberration diagrams, the value of the maximum semi-field angle is shown after "ω =". The FNo. and ω in the aberration diagrams in the upper part correspond to FNo and ωm in the above conditional expressions, respectively.

[0397] Regarding the notations, meanings, recording methods, and illustration methods of the various data related to Example 1 above, as long as there is no special description, they are basically the same in the following examples, so the repeated description is omitted below.

[0398] [Example 2]

[0399] The cross-sectional view of the structure of the imaging lens of Example 2 is shown in Figure 5In the middle. The imaging lens of Example 2 includes, in order from the object side to the image side, a front group GF with positive refractive power, an aperture stop St, and a rear group GR with positive refractive power.

[0400] The front group GF includes a first focusing lens group Gf1 with positive refractive power, and the rear group GR includes a second focusing lens group Gf2 with positive refractive power.

[0401] The front group GF includes seven lenses L11 to L17 in order from the object side to the image side. The rear group GR includes six lenses L21 to L26 in order from the object side to the image side. The first focusing lens group Gf1 includes the lens L15. The second focusing lens group Gf2 includes the lens L23. When focusing from an infinitely distant object to the nearest object, the first focusing lens group Gf1 moves toward the image side, the second focusing lens group Gf2 moves toward the image side, and the other lenses and the aperture stop St are fixed relative to the image plane Sim.

[0402] Regarding the imaging lens of Example 2, the basic lens data is shown in Table 5, the specifications are shown in Table 6, the variable surface intervals are shown in Table 7, the aspherical coefficients are shown in Table 8, and the various aberration diagrams are shown in Figure 6 In the middle.

[0403] [Table 5]

[0404] Example 2

[0405]

[0406] [Table 6]

[0407] Example 2

[0408] f 14.42 Bf 11.48 FNo. 1.80 2ωm[°] 114.6

[0409] [Table 7]

[0410] Example 2

[0411] Infinity |β|＝0.2 DD8 0.9877 5.1374 DD10 5.1968 1.0471 DD18 2.6034 3.2363 DD20 3.9552 3.3224

[0412] [Table 8]

[0413] Example 2

[0414] Sn 1 2 7 8 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 3.1646429E-05 3.5932668E-05 —2.6655598E-05 —1.9862005E-05 A6 —8.8595827E-08 —7.3079816E-08 —1.1078776E-07 —1.2662827E-07 A8 1.6321146E-10 5.4187486E-11 —3.1979009E-10 —3.0282497E-10 A10 -1.5712613E-13 1.9065278E-14 —4.0676387E-13 8.5998462E-13 A12 3.7117432E-17 1.3167523E-16 4.1753669E-15 6.6766583E-16 A14 7.6404991E-20 —1.4696512E-19 8.5627624E-18 —1.8126455E-19 A16 —4.2453268E-23 1.6015330E-21 —2.1377968E-19 8.2030202E-20 A18 —4.4957760E-26 —3.6173459E-24 1.1673619E-21 —5.2699369E-22 A20 3.7983890E-29 —1.4998163E-27 —2.2244026E-24 8.0304528E-25

[0415] Sn 15 16 KA 1.0000000E+00 1.0000000E+00 A4 2.3844112E-04 1.7058931E-04 A6 —1.2117480E-07 —2.7303946E-07 A8 —1.9860437E-09 —1.0580255E-09 A10 4.1860847E-11 2.5625349E-11

[0416] Sn 21 22 KA 2.3198043E-01 0.0000000E+00 A4 5.3914166E-05 1.0304474E-04 A6 2.8341847E-07 3.5753773E-07 A8 —7.5976230E-10 5.2044626E—10 A10 —3.2631774E-14 -2.0034296E-11 A12 -3.5075599E-13 -7.7934422E—14 A14 3.7351677E-15 1.3954054E-15 A16 -1.4719214E-17 -4.6569127E-18 A18 2.0880900E-20 3.8118023E-21

[0417] [Example 3]

[0418] A cross-sectional view of the structure of the imaging lens of Example 3 is shown in Figure 7In the imaging lens of Embodiment 3, from the object side to the image side, it sequentially includes a front group GF with positive refractive power, an aperture stop St, and a rear group GR with positive refractive power.

[0419] The front group GF includes a first focusing lens group Gf1 with positive refractive power, and the rear group GR includes a second focusing lens group Gf2 with negative refractive power.

[0420] The front group GF sequentially includes seven lenses L11 to L17 from the object side to the image side. The rear group GR sequentially includes six lenses L21 to L26 from the object side to the image side. The first focusing lens group Gf1 includes the lens L15. The second focusing lens group Gf2 includes the lenses L21 and L22. When focusing from an infinitely distant object to the nearest object, the first focusing lens group Gf1 moves toward the image side, the second focusing lens group Gf2 moves toward the object side, and other lenses and the aperture stop St are fixed relative to the image plane Sim.

[0421] Regarding the imaging lens of Embodiment 3, the basic lens data is shown in Table 9, the specifications are shown in Table 10, the variable surface intervals are shown in Table 11, the aspherical coefficients are shown in Table 12, and each aberration diagram is shown in Figure 8 In.

[0422] [Table 9]

[0423] Embodiment 3

[0424]

[0425] [Table 10]

[0426] Embodiment 3

[0427] f 14.41 Bf 15.98 FNo. 1.80 2ωm[°] 115.2

[0428] [Table 11]

[0429] Embodiment 3

[0430] Infinity |β|＝0.2 DD8 1.4156 5.0988 DD10 4.7079 1.0247 DD14 8.7131 7.2684 DD18 0.9109 2.3557

[0431] [Table 12]

[0432] Embodiment 3

[0433] Sn 1 2 7 8 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 2.8117609E-05 2.5965534E-05 —1.6665129E-05 —7.4674492E-06 A6 —8.2275513E-08 —6.4762502E-08 —1.1143228E-07 —1.2448448E-07 A8 1.6693106E-10 6.3306025E-11 —2.9563098E-10 —2.5297391E-10 A10 -1.7503493E-13 3.0830653E-15 —3.4812635E-13 9.0921830E-13 A12 3.6591253E-17 3.2613345E-17 5.5172601E-15 —2.8163701E-16 A14 1.0373695E-19 —3.0854579E-19 1.3022955E-17 —4.8292561E-18 A16 —4.2929045E-23 1.5867875E-21 —2.4315998E-19 7.7860085E-20 A18 —7.6015635E-26 —2.9435328E-24 8.0177100E-22 —4.4252887E-22 A20 5.4223817E-29 8.7926076E-28 —3.9026145E-25 9.6100694E-25

[0434] Sn 15 16 KA 1.0000000E+00 1.0000000E+00 A4 1.6670290E-04 1.1659960E-04 A6 1.8419896E-07 —7.5916042E-09 A8 —2.7900499E-09 —1.6627086E-09 A10 2.3110183E-11 1.0747565E-11

[0435] Sn 21 22 KA 4.4466604E-06 0.0000000E+00 A4 5.4822834E-05 9.1857545E-05 A6 2.8599048E-07 3.5133501E-07 A8 —6.6439018E-10 4.6504122E-10 A10 —2.0335410E-13 —1.9580985E—11 A12 -3.5458181E-13 -7.9250741E-14 A14 3.6526351E-15 1.3745112E-15 A16 -1.3812464E-17 -4.7114908E-18 A18 1.8449356E-20 4.4561391E-21

[0436] [Embodiment 4]

[0437] A cross-sectional view of the structure of the imaging lens of Embodiment 4 is shown in Fig. 9 In the imaging lens of Embodiment 4, from the object side to the image side, it successively includes a front group GF with positive optical power, an aperture stop St, and a rear group GR with positive optical power.

[0438] The imaging lens of Embodiment 4 has only one focusing lens group. Hereinafter, in an imaging lens having only one focusing lens group, this focusing lens group is referred to as a single focusing lens group Gf. The front group GF includes the single focusing lens group Gf with positive optical power.

[0439] The front group GF successively includes six lenses L11 to L16 from the object side to the image side. The rear group GR successively includes six lenses L21 to L26 from the object side to the image side. The single focusing lens group Gf includes lenses L13 and L14. When focusing from an infinitely distant object to the nearest object, the single focusing lens group Gf moves toward the image side, and the other lenses and the aperture stop St are fixed with respect to the image plane Sim.

[0440] Regarding the imaging lens of Embodiment 4, the basic lens data is shown in Table 13, the specifications are shown in Table 14, the variable surface intervals are shown in Table 15, the aspherical coefficients are shown in Table 16, and the various aberration diagrams are shown in Fig.10 in.

[0441] [Table 13]

[0442] Embodiment 4

[0443]

[0444] [Table 14]

[0445] Embodiment 4

[0446] f 16.40 Bf 15.48 FNo. 1.79 2ωm[°] 108.2

[0447] [Table 15]

[0448] Embodiment 4

[0449] Infinity |β|＝0.1 DD4 16.0445 5.8623 DD8 6.8881 1.0258

[0450] [Table 16]

[0451] Embodiment 4

[0452] Sn 1 2 5 6 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 2.6876880E-05 2.5908960E-05 1.1840490E-05 1.6429270E-05 A6 —6.5155548E-08 —4.0573072E-08 1.1181613E-08 1.9043996E-09 A8 1.1849851E-10 3.9612045E-11 -4.4193150E-11 —2.9408529E-11 A10 —1.4541015E—13 —1.2590808E-13 —4.1336304E-14 3.9183753E-14 A12 6.7878186E-17 —7.5531238E-17 5.4577349E-16 3.0617433E-16 A14 6.1263280E-20 —2.6135743E-19 2.5988180E-18 8.3406839E-19 A16 —7.7380637E-23 1.7710601E-21 2.0684417E-21 1.3862713E-21 A18 —5.7191273E-27 —2.6849596E-24 —5.2584297E-23 —1.6895665E-23 A20 2.5007618E-29 1.6872976E-27 6.4903390E-26 3.4627595E-27

[0453] Sn 13 14 KA 1.0000000E+00 1.0000000E+00 A4 3.1383832E-06 —4.7970614E-05 A6 1.8623269E-08 —1.0256115E-07 A8 —2.1163508E-10 2.7723141E-10 A10 2.8032775E-13 —7.3923764E-13

[0454] Sn 19 20 KA 2.5883859E-04 0.0000000E+00 A4 —2.9623949E-05 5.0365146E-05 A6 9.5351570E-08 2.3752922E-07 A8 —6.8160371E—10 2.7782660E-10 A10 5.4673972E-12 —1.3772999E—11 A12 —3.1903467E-13 —4.6508853E—14 A14 3.6107333E-15 1.4081180E—15 A16 —1.7182393E-17 —1.0674847E—17 A18 3.2671924E-20 2.9946632E-20

[0455] [Embodiment 5]

[0456] The cross-sectional view of the structure of the imaging lens of Example 5 is shown in Fig.11 . The imaging lens of Example 5 includes, in order from the object side to the image side, a front group GF with a negative optical power, an aperture stop St, and a rear group GR with a positive optical power. The front group GF includes a single focusing lens group Gf with a positive optical power.

[0457] The front group GF includes six lenses L11 to L16 in order from the object side to the image side. The rear group GR includes six lenses L21 to L26 in order from the object side to the image side. The single focusing lens group Gf includes the lens L14. When focusing from an infinitely distant object to the nearest object, the single focusing lens group Gf moves toward the image side, and the other lenses and the aperture stop St are fixed relative to the image plane Sim.

[0458] Regarding the imaging lens of Example 5, the basic lens data is shown in Table 17, the specifications are shown in Table 18, the variable surface intervals are shown in Table 19, the aspherical coefficients are shown in Table 20, and the various aberration diagrams are shown in Fig.12 .

[0459] [Table 17]

[0460] Example 5

[0461]

[0462] [Table 18]

[0463] Example 5

[0464] f 15.60 Bf 12.38 FNo. 1.80 2ωm[°] 106.8

[0465] [Table 19]

[0466] Example 5

[0467] Infinity |β|＝0.1 DD6 1.5600 3.0519 DD8 2.5152 1.0233

[0468] [Table 20]

[0469] Example 5

[0470] Sn 1 2 7 8 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A4 1.9993455E-05 1.2574885E-05 -1.8386035E-05 —8.7585753E-06 A6 —6.2129387E-08 —7.4389332E-08 —7.0533279E-08 —5.9871153E-08 A8 1.2334559E-10 5.8950066E-11 3.8406279E-10 2.8597529E-10 A10 —1.4249333E—13 —3.7266929E-14 —1.8051937E-12 —1.7918046E-12 A12 5.9565033E-17 2.7180283E-17 —1.3027240E-14 —6.0898737E-15 A14 5.2360489E-20 —2.7640377E-19 9.0327176E-17 7.5914744E-17 A16 —5.7281327E-23 1.4654631E-21 —3.3995350E-19 —1.0214852E-19 A18 —3.4866334E-27 —3.2278012E-24 2.7986735E-21 —1.2611226E-21 A20 1.3966383E-29 2.2378639E-27 —1.3865938E-23 3.1783713E-24

[0471] Sn 13 14 KA 1.0000000E+00 1.0000000E+00 A4 3.1407441E-06 —1.7315088E-05 A6 —2.5625577E-08 —1.5086698E-07 A8 —3.3191617E-10 —4.0883393E-10 A10 -2.1912461E-13 —1.5497653E-13

[0472] Sn 19 20 KA 2.2799995E+00 0.0000000E+00 A4 —3.5983481E-05 4.1309171E-05 A6 1.2677135E-07 2.8366614E-07 A8 —4.6317329E—10 6.5276464E-10 A10 5.5512850E-12 —1.1260438E—11 A12 —3.0855454E-13 —5.2177690E—14 A14 3.7143107E-15 1.3860832E—15 A16 —1.7413909E-17 —7.9578153E—18 A18 2.9427483E-20 1.5104091E-20

[0473] [Example 6]

[0474] The cross-sectional view of the structure of the imaging lens of Example 6 is shown in Fig.13In the imaging lens of Example 6, from the object side to the image side, it sequentially includes a front group GF with negative refractive power, an aperture stop St, and a rear group GR with positive refractive power. The rear group GR includes a first focusing lens group Gf1 with positive refractive power and a second focusing lens group Gf2 with positive refractive power.

[0475] The front group GF sequentially includes seven lenses L11 to L17 from the object side to the image side. The rear group GR sequentially includes seven lenses L21 to L27 from the object side to the image side. The first focusing lens group Gf1 includes the lens L21. The second focusing lens group Gf2 includes the lenses L24 and L25. When focusing from an infinitely distant object to the nearest object, the first focusing lens group Gf1 moves toward the object side, the second focusing lens group Gf2 moves toward the image side, and the other lenses and the aperture stop St are fixed relative to the image plane Sim.

[0476] Regarding the imaging lens of Example 6, the basic lens data is shown in Table 21, the specifications are shown in Table 22, the variable surface intervals are shown in Table 23, the aspherical coefficients are shown in Table 24, and the aberration diagrams are shown in Fig.14 in.

[0477] [Table 21]

[0478] Example 6

[0479]

[0480] [Table 22]

[0481] Example 6

[0482] f 14.33 Bf 12.89 FNo. 1.86 2ωm[°] 116.2

[0483] [Table 23] Example 6

[0484] Infinity |β|＝0.2 DD14 6.4852 0.9998 DD16 4.1539 9.6393 DD19 1.1826 2.3352 DD23 2.3749 1.2224

[0485] [Table 24]

[0486] Example 6

[0487] Sn 1 2 12 13 KA 1.0000000E+00 4.0600000E-01 1.0000000E+00 1.0000000E+00 A3 1.1130668E-03 1.2355283E-03 5.4426952E-06 1.9495327E-05 A4 -6.2587431E-05 -8.6403921E-05 -6.4900732E-05 -4.7043410E-05 A5 1.6420705E-06 5.0168904E-06 3.1258788E-06 2.2934277E-06 A6 8.0545594E-09 -5.3468296E-08 -3.7323113E-07 -1.1450915E-07 A7 -4.4379146E-10 -7.3606539E-09 -3.3572361E-08 -3.0010602E-08 A8 -2.1185776E-11 1.3697219E-10 1.7899206E-09 -4.1505449E-10 A9 -1.8619370E-13 1.0363163E-11 4.7911870E-10 2.1419421E-10 A10 9.7165205E-15 4.1664157E-13 2.7880129E-12 2.3350095E-11 A11 4.4566405E-16 3.6693552E-14 -2.3630100E-12 -5.2240307E-14 A12 9.7695746E-18 -2.4111329E-15 -2.0579060E-13 -1.5291380E-13 A13 3.9029560E-19 -6.7763851E-17 -2.2199812E-14 -1.5392586E-14 A14 -4.6853534E-21 -5.1863163E-18 -1.2108694E-17 -8.7851057E-16 A15 -5.3246923E-22 -1.5674241E-19 8.8196010E-17 4.6836703E-17 A16 -1.7559303E-23 1.0634566E-20 9.1150678E-18 -2.1079173E-18 A17 3.1028116E-26 8.7449991E-22 2.1984064E-18 1.7600108E-18 A18 5.2139237E-27 3.8306770E-23 9.3088443E-20 1.5191194E-20 A19 2.7109218E-28 5.6327679E-25 -3.1785582E-21 -6.0163279E-22 A20 1.9039970E-30 -1.4766374E-25 -1.8615683E-21 -5.5510394E-22

[0488] Sn 24 25 KA 1.0000000E+00 1.0000000E+00 A3 2.1066405E-04 2.5555599E-04 A4 -2.0376113E-05 -9.2662367E-06 A5 -3.6939741E-06 -2.5309496E-06 A6 -6.2465311E-08 -3.9899943E-08 A7 9.0613569E-09 -2.1221607E-08 A8 4.5558989E-11 2.6643082E-09 A9 -9.6130056E-12 7.3982213E-11 A10 -1.4168502E-12 -1.7758617E-11 A11 7.1490824E-14 2.8448624E-13 A12 8.7965864E-15 4.8141043E-14 A13 4.1777386E-16 -3.1801329E-16 A14 4.6122217E-17 -5.0713331E-18 A15 9.3573610E-20 -5.8929155E-18 A16 -1.4334552E-19 -1.7749326E-19 A17 -2.3616664E-20 -1.4187355E-22 A18 -1.1890302E-21 2.4768075E-22 A19 -3.7672214E-23 1.8836036E-23 A20 9.7211149E-24 1.1689402E-24

[0489] [Example 7]

[0490] A cross-sectional view of the structure of the imaging lens of Example 7 is shown in Fig.15In the middle. The imaging lens of Embodiment 7 includes, in order from the object side to the image side, a front group GF having a negative optical power, an aperture stop St, and a rear group GR having a positive optical power. The rear group GR includes a first focusing lens group Gf1 having a positive optical power and a second focusing lens group Gf2 having a negative optical power.

[0491] The front group GF includes, in order from the object side to the image side, seven lenses L11 to L17. The rear group GR includes, in order from the object side to the image side, seven lenses L21 to L27. The first focusing lens group Gf1 includes five lenses L21 to L25. The second focusing lens group Gf2 includes lens L26. When focusing from an infinitely distant object to the nearest object, the first focusing lens group Gf1 moves toward the object side, the second focusing lens group Gf2 moves toward the object side, and the other lenses and the aperture stop St are fixed with respect to the image plane Sim.

[0492] Regarding the imaging lens of Embodiment 7, the basic lens data is shown in Table 25, the specifications are shown in Table 26, the variable surface intervals are shown in Table 27, the aspherical coefficients are shown in Table 28, and the aberration diagrams are shown in Fig.16 In the middle.

[0493] [Table 25]

[0494] Embodiment 7

[0495]

[0496] [Table 26]

[0497] Embodiment 7

[0498] f 14.32 Bf 16.80 FNo. 1.85 2ωm[°] 115.4

[0499] [Table 27] Embodiment 7

[0500] Infinity |β|＝0.2 DD14 6.1826 1.0000 DD23 3.3508 6.3233 DD25 1.0002 3.2104

[0501] [Table 28]

[0502] Embodiment 7

[0503] Sn 1 2 12 13 KA 1.0000000E+00 4.0600000E-01 1.0000000E+00 1.0000000E+00 A3 1.4563389E-03 1.6008774E-03 -1.4599114E-05 -2.2404316E-05 A4 -6.9947357E-05 -9.1708750E-05 -8.7310910E-05 -7.0097779E-05 A5 1.2168197E-06 5.3874617E-06 -4.2061533E-06 5.6728352E-07 A6 6.8181833E-09 -1.0978214E-07 2.1374328E-07 -2.2242780E-07 A7 -3.6153583E-11 -4.9388725E-09 2.9826892E-09 2.0723585E-09 A8 -7.1433582E-12 1.6577604E-10 -8.0949140E-11 -3.7955800E-10 A9 -1.1746748E-13 5.1098055E-12 6.7385417E-12 1.1219073E-10 A10 -7.9226931E-16 1.1871981E-13 -2.5193629E-11 2.5956705E-11 A11 -3.2027709E-17 2.3059248E-14 -2.7171998E-12 -1.6004919E-12 A12 -1.5454775E-18 -7.9306601E-16 5.4064605E-14 6.0387446E-14 A13 2.1148757E-19 -2.9466919E-17 2.6222856E-14 -2.0435544E-14 A14 9.3924198E-21 -2.6166184E-18 4.7464588E-15 -1.3225203E-15 A15 -2.6128168E-23 -5.9878467E-20 2.0183063E-16 -3.4496975E-17 A16 -4.1274720E-24 -1.3351742E-21 -1.8782731E-17 2.1906678E-17 A17 -1.3695846E-25 4.9862404E-22 -1.2524000E-18 1.0867489E-18 A18 -5.7439281E-27 1.4794166E-23 -5.4006682E-19 1.0470313E-20 A19 -2.0651520E-29 5.8534049E-25 -1.7126952E-20 2.1519045E-21 A20 6.5777134E-30 -7.5648251E-26 4.7552657E-21 -1.1615399E-21

[0504] Sn 24 25 KA 1.0000000E+00 1.0000000E+00 A3 -1.0009845E-05 6.6405444E-06 A4 -6.9989291E-05 -6.2161635E-05 A5 1.1868054E-07 1.5665398E-06 A6 1.2834279E-07 1.5607171E-07 A7 8.0814696E-09 -1.6495471E-08 A8 6.9716325E-11 2.4323067E-09 A9 -1.1672544E-11 3.7747028E-11 A10 -3.0045845E-12 -1.8904887E-11 A11 -1.5910189E-14 2.0535199E-13 A12 5.5310605E-16 4.9533539E-14 A13 5.7007644E-16 -1.3977011E-16 A14 3.3720303E-17 1.6062079E-17 A15 1.9725817E-18 -7.0853184E-18 A16 3.4079027E-19 -2.0082047E-19 A17 -6.5202762E-20 2.1461368E-21 A18 -1.8661772E-21 -3.5099980E-22 A19 -5.1655794E-23 6.0433112E-23 A20 1.9095233E-23 2.2607772E-24

[0505] [Embodiment 8]

[0506] A cross-sectional view of the structure of the imaging lens of Embodiment 8 is shown in Fig.17Among them, the imaging lens of Embodiment 8 sequentially includes a front group GF with positive refractive power, an aperture stop St, and a rear group GR with positive refractive power from the object side to the image side. The rear group GR includes a first focusing lens group Gf1 with positive refractive power and a second focusing lens group Gf2 with negative refractive power.

[0507] The front group GF sequentially includes seven lenses L11 to L17 from the object side to the image side. The rear group GR sequentially includes seven lenses L21 to L27 from the object side to the image side. The first focusing lens group Gf1 includes four lenses L22 to L25. The second focusing lens group Gf2 includes the lens L26. When focusing from an infinitely distant object to the nearest object, the first focusing lens group Gf1 moves toward the object side, and the second focusing lens group Gf2 moves toward the object side, while the other lenses and the aperture stop St are fixed relative to the image plane Sim.

[0508] Regarding the imaging lens of Embodiment 8, the basic lens data is shown in Table 29, the specifications are shown in Table 30, the variable surface intervals are shown in Table 31, the aspherical coefficients are shown in Table 32, and the various aberration diagrams are shown in Fig.18 Among them.

[0509] [Table 29]

[0510] Embodiment 8

[0511]

[0512] [Table 30]

[0513] Embodiment 8

[0514] f 14.33 Bf 13.09 FNo. 1.86 2ωm[°] 113.6

[0515] [Table 31] Embodiment 8

[0516] Infinity |β|＝0.2 DD16 7.1426 1.0798 DD23 1.2009 4.7625 DD25 1.4455 3.9467

[0517] [Table 32]

[0518] Embodiment 8

[0519] Sn 1 2 12 13 KA 1.0000000E+00 4.0600000E-01 1.0000000E+00 1.0000000E+00 A3 1.5044687E-03 1.6081235E-03 -1.7640046E-05 -2.5520752E-05 A4 -6.0576478E-05 -7.9112763E-05 -6.5268221E-05 -5.0505602E-05 A5 6.9751108E-07 5.0059544E-06 -2.6967134E-06 -1.4764539E-06 A6 4.1814259E-09 -6.6975551E-08 5.7533126E-08 -6.1887626E-08 A7 1.8527978E-10 -6.0533816E-09 -1.2846159E-08 -3.5520413E-09 A8 -1.4535789E-12 4.6332939E-11 -5.7255052E-10 -1.5741549E-10 A9 -1.7102833E-14 5.3784519E-12 8.2329345E-11 -4.5134372E-11 A10 -6.5810610E-15 5.8400260E-14 -6.6264522E-12 1.4347703E-12 A11 2.9472381E-18 2.4874264E-14 -6.4285488E-14 -9.2611065E-14 A12 -6.4089527E-18 -3.4486617E-16 6.7921826E-15 4.6762694E-14 A13 1.9824580E-19 -4.8310785E-17 -1.1460733E-14 -5.3010879E-15 A14 6.5099419E-21 -1.9393760E-18 8.1484393E-16 1.1867052E-16 A15 3.9348857E-23 -8.1019554E-21 -2.7941110E-17 2.2170850E-17 A16 -1.1860135E-24 3.2433331E-21 -5.0637487E-18 -5.8770524E-18 A17 -2.4146505E-26 3.0522459E-22 9.3564553E-19 8.0662016E-19 A18 -5.3874387E-27 1.4764503E-23 -2.8165811E-20 -7.6034462E-20 A19 -5.3090227E-29 2.2998455E-26 3.2264667E-21 -2.9652175E-22 A20 3.7120679E-30 -8.5816190E-26 -6.0711217E-22 2.1114696E-22

[0520] Sn 24 25 KA 1.0000000E+00 1.0000000E+00 A3 -7.1438812E-05 -4.8369974E-05 A4 -6.9026933E-05 -6.8048213E-05 A5 -1.4996373E-06 7.6267858E-07 A6 1.5912017E-07 1.0872940E-07 A7 8.0102885E-09 -1.4955092E-08 A8 3.3871384E-11 2.5405486E-09 A9 -1.3283033E-11 5.0008904E-11 A10 -9.2870055E-13 -1.8572239E-11 A11 -2.5498514E-14 1.4280146E-13 A12 -2.1515520E-16 4.3960302E-14 A13 6.9513946E-17 -4.1708494E-16 A14 1.0192396E-17 2.6872017E-18 A15 1.5102577E-19 -4.8558048E-18 A16 -8.2001206E-20 -1.0490368E-19 A17 -9.8363016E-21 3.6267694E-21 A18 -8.6236872E-22 4.9802507E-22 A19 2.1488100E-23 -1.4380110E-24 A20 6.4185642E-24 1.3447606E-24

[0521] [Embodiment 9]

[0522] A cross-sectional view of the structure of the imaging lens of Embodiment 9 is shown in Fig.19 Among them. The imaging lens of Embodiment 9 sequentially includes a front group GF with positive refractive power, an aperture stop St, and a rear group GR with positive refractive power from the object side to the image side. The rear group GR includes a single focusing lens group Gf with negative refractive power.

[0523] The front group GF includes eight lenses L11 to L18 in order from the object side to the image side.

[0524] The rear group GR includes six lenses L21 to L26 in order from the object side to the image side. The single-focus lens group Gf includes the lens L25. When focusing from an infinitely distant object to the nearest object, the single-focus lens group Gf moves toward the image side, and the other lenses and the aperture stop St are fixed with respect to the image plane Sim.

[0525] Regarding the imaging lens of Example 9, the basic lens data is shown in Table 33, the specifications are shown in Table 34, the variable surface intervals are shown in Table 35, the aspherical coefficients are shown in Table 36, and the aberration diagrams are shown in Fig. 20 in.

[0526] [Table 33]

[0527] Example 9

[0528]

[0529] [Table 34]

[0530] Example 9

[0531] f 14.32 Bf 13.45 FNo. 1.86 2ωm[°] 115.4

[0532] [Table 35] Example 9

[0533] Infinity |β|＝0.1 DD22 1.0000 2.0437 DD24 9.5386 8.4949

[0534] [Table 36]

[0535] Example 9

[0536] Sn 1 2 10 11 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A3 5.8243364E-04 5.6296992E-04 -1.1597039E-05 -2.2244300E-06 A4 6.8406989E-06 1.7177135E-05 -8.5158524E-07 -1.5976539E-06 A5 -3.5263439E-07 -8.8391527E-07 -1.5301126E-07 -1.6877820E-08 A6 -3.6796717E-08 5.6980418E-08 -2.4278588E-10 -1.3767010E-09 A7 2.8956325E-10 7.4818749E-10 1.2631336E-10 -8.8628408E-12 A8 3.6012519E-11 -2.2712726E-10 5.2319118E-12 2.1193378E-12 A9 2.8202647E-13 4.9845163E-13 9.4124109E-14 1.2635048E-13 A10 2.6390132E-15 2.8937199E-14 -2.6779354E-15 4.1336709E-15 A11 -4.3632820E-16 -2.2930969E-15 -3.4596045E-16 6.1797205E-17 A12 -3.2569955E-17 6.6386207E-16 -1.8032082E-17 -2.0663461E-18 A13 -3.0917492E-19 -5.4104560E-18 -6.2728858E-19 -1.7215046E-19 A14 -1.1611878E-21 3.3402545E-19 -7.8237225E-21 -8.8464827E-21 A15 9.8642854E-22 -3.0182838E-21 9.4568627E-22 -2.5477575E-22 A16 1.0264474E-23 5.5820531E-22 1.0828108E-22 1.9687167E-24 A17 1.1124620E-24 1.9346167E-23 7.1723824E-24 1.0085214E-24 A18 2.0843602E-26 -1.0166546E-23 3.6109703E-25 1.3436712E-25 A19 -4.5993706E-27 1.0032321E-25 1.1350025E-26 1.2033175E-26 A20 7.9672639E-29 5.4716231E-27 -1.7266041E-28 1.0885826E-27

[0537] Sn 16 17 23 24 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A3 9.1804611E-05 3.0390417E-05 1.4294705E-04 1.4302981E-04 A4 1.3646433E-05 3.6170671E-05 2.1702862E-05 3.6011878E-05 A5 1.6547977E-06 6.4788016E-06 -2.6461004E-06 -2.9607187E-06 A6 2.5005463E-07 -4.9968438E-07 -5.7752956E-08 -1.5321073E-07 A7 8.3309977E-09 -3.4780827E-08 -8.2189277E-09 -6.7527960E-09 A8 -7.3335615E-10 3.5958354E-09 -2.9945976E-10 1.2739858E-09 A9 -1.1251316E-10 4.8602806E-10 8.1569145E-11 9.3705590E-11 A10 -5.0899075E-12 2.8421117E-11 1.2383812E-11 -7.2168253E-12 A11 6.4408943E-13 -7.2184845E-13 4.1273585E-13 -1.7078377E-15 A12 8.6990091E-14 -3.8174580E-13 -3.1728148E-13 -9.2864783E-14 A13 9.1760639E-15 -4.1860961E-14 -3.1176326E-15 -2.5635002E-15 A14 2.1818308E-16 -3.1396625E-15 3.4197575E-15 1.3736879E-15 A15 -6.5084741E-17 -3.0095963E-17 -2.8600608E-17 3.6292380E-18 A16 -1.0233760E-17 6.6536581E-17 -1.8752197E-17 -6.5661086E-18 A17 -1.3077558E-19 5.6307543E-18 1.1594651E-19 4.9135708E-20 A18 8.5083057E-20 -4.7814112E-19 6.2677146E-20 1.3264835E-20 A19 2.3139214E-21 2.9462918E-20 6.0639339E-22 -2.7749446E-22 A20 -1.9245210E-22 -3.3205792E-21 -1.4060995E-22 2.2862951E-24

[0538] [Example 10]

[0539] A cross-sectional view of the structure of the imaging lens of Example 10 is shown in Fig.21 in. The imaging lens of Example 10 includes a front group GF with a positive focal power, an aperture stop St, and a rear group GR with a positive focal power in order from the object side to the image side. The rear group GR includes a single-focus lens group Gf with a negative focal power.

[0540] The front group GF includes eight lenses L11 to L18 in order from the object side to the image side. The rear group GR includes six lenses L21 to L26 in order from the object side to the image side. The single focusing lens group Gf includes the lens L25. When focusing from an infinitely distant object to the nearest object, the single focusing lens group Gf moves toward the image side, and the other lenses and the aperture stop St are fixed relative to the image plane Sim.

[0541] Regarding the imaging lens of Embodiment 10, the basic lens data is shown in Table 37, the specifications are shown in Table 38, the variable surface intervals are shown in Table 39, the aspherical coefficients are shown in Table 40, and the aberration diagrams are shown in Fig. 22 it.

[0542] [Table 37]

[0543] Embodiment 10

[0544]

[0545] [Table 38]

[0546] Embodiment 10

[0547] f 14.32 Bf 11.11 FNo. 1.86 2ωm[°] 115.0

[0548] [Table 39] Embodiment 10

[0549] Infinity |β|＝0.1 DD22 1.0001 2.0987 DD24 11.0119 9.9132

[0550] [Table 40]

[0551] Embodiment 10

[0552] Sn 1 2 10 11 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A3 5.9741947E-04 5.8061925E-04 -1.1755086E-05 -1.8831625E-07 A4 5.8517422E-06 1.6696533E-05 -1.9518821E-07 -1.2026814E-06 A5 -3.9121645E-07 -9.1924162E-07 -1.2951732E-07 7.4554151E-09 A6 -3.7034533E-08 5.4415332E-08 4.2344846E-10 -1.0116660E-09 A7 2.9907080E-10 6.2855061E-10 1.1213765E-10 -6.1144247E-12 A8 3.7071703E-11 -2.3079272E-10 3.2196208E-12 1.7083422E-12 A9 3.2199609E-13 4.3106478E-13 -5.1751774E-15 9.1008211E-14 A10 2.3327173E-15 2.9870577E-14 -4.3504626E-15 1.8651248E-15 A11 -4.6989768E-16 -2.1472521E-15 -2.5150624E-16 -5.6217683E-17 A12 -3.2747286E-17 6.7283351E-16 -9.1527535E-18 -8.5607170E-18 A13 -3.1173451E-19 -4.9857278E-18 -1.6945845E-19 -4.9865532E-19 A14 1.9571835E-22 3.5166243E-19 4.5133991E-21 -1.5630630E-20 A15 9.8590532E-22 -2.3393764E-21 6.5631355E-22 1.2271482E-22 A16 1.0911914E-23 5.8290961E-22 4.4858560E-23 6.4222292E-23 A17 1.0651778E-24 2.0177059E-23 2.4954715E-24 5.6893582E-24 A18 1.8665115E-26 -1.0146023E-23 1.4143340E-25 3.2964477E-25 A19 -4.5526703E-27 1.0022311E-25 9.5075179E-27 1.1992643E-26 A20 8.0404154E-29 5.3989851E-27 7.4237952E-28 -1.5343357E-28

[0553] Sn 16 17 23 24 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A3 9.2211529E-05 2.3922460E-05 1.7489946E-04 1.7707726E-04 A4 1.2846787E-05 4.0298551E-05 2.2058410E-05 3.7341240E-05 A5 1.8693900E-06 6.6963212E-06 -2.5999009E-06 -3.0272553E-06 A6 2.4220050E-07 -5.2049457E-07 -5.6720629E-08 -1.5577651E-07 A7 6.2706947E-09 -3.6489364E-08 -8.4685705E-09 -5.9762461E-09 A8 -8.6246911E-10 3.6144266E-09 -3.2342542E-10 1.3399900E-09 A9 -1.0826186E-10 4.9965159E-10 8.1499710E-11 9.3225830E-11 A10 -3.5792389E-12 2.9835245E-11 1.2479586E-11 -7.6723208E-12 A11 8.1410064E-13 -6.4313346E-13 4.2078109E-13 -4.6689323E-14 A12 9.7236806E-14 -3.8236297E-13 -3.1694054E-13 -9.5097709E-14 A13 9.0925040E-15 -4.2341163E-14 -3.0967683E-15 -2.5298332E-15 A14 1.2755204E-16 -3.2397823E-15 3.4246529E-15 1.3942967E-15 A15 -7.6911044E-17 -3.4383975E-17 -2.7968491E-17 6.1879826E-18 A16 -1.0300505E-17 6.8549678E-17 -1.8727436E-17 -6.3560858E-18 A17 -1.7789735E-19 6.0637000E-18 1.2593530E-19 6.1895649E-20 A18 8.8301693E-20 -4.9640523E-19 6.3264658E-20 1.2963465E-20 A19 1.4817734E-21 2.1710366E-20 5.6363129E-22 -3.2976395E-22 A20 -1.4771485E-22 -2.9082882E-21 -1.4833368E-22 -9.6173902E-24

[0554] [Embodiment 11]

[0555] A cross-sectional view of the structure of the imaging lens of Embodiment 11 is shown in Fig.23 it. The imaging lens of Embodiment 11 includes a front group GF having a negative refractive power, an aperture stop St, and a rear group GR having a positive refractive power in order from the object side to the image side. The rear group GR includes a single focusing lens group Gf having a positive refractive power.

[0556] The front group GF includes six lenses L11 to L16 in order from the object side to the image side. The rear group GR includes six lenses L21 to L26 in order from the object side to the image side. The single focusing lens group Gf includes five lenses L21 to L25. When focusing from an infinitely distant object to the nearest object, the single focusing lens group Gf moves toward the object side, and the other lenses and the aperture stop St are fixed relative to the image plane Sim.

[0557] Regarding the imaging lens of Example 11, the basic lens data is shown in Table 41, the specifications are shown in Table 42, the variable surface intervals are shown in Table 43, the aspherical coefficients are shown in Table 44, and the aberration diagrams are shown in Fig.24 .

[0558] [Table 41]

[0559] Example 11

[0560]

[0561] [Table 42]

[0562] Example 11

[0563] f 16.32 Bf 13.65 FNo. 1.85 2ωm[°] 109.4

[0564] [Table 43] Example 11

[0565] Infinity |β|＝0.1 DD12 2.5002 0.1463 DD21 1.9092 4.2631

[0566] [Table 44]

[0567] Example 11

[0568] Sn 1 2 10 11 KA 1.0000000E+00 4.0600000E-01 1.0000000E+00 1.0000000E+00 A3 4.3969473E-04 4.6895452E-04 -4.7898378E-06 -1.8036328E-05 A4 -1.3082554E-05 -1.3924997E-05 -2.7756373E-05 -6.2834745E-06 A5 9.1091353E-08 7.6963560E-07 -7.6514921E-07 -2.5299739E-07 A6 1.3414426E-09 5.4515691E-09 3.9831251E-08 -7.7178228E-08 A7 2.1894310E-10 -2.9680840E-09 -3.9820685E-09 2.7477170E-09 A8 9.3647117E-12 1.5713646E-10 -2.0962791E-10 9.7965258E-12 A9 -1.8813333E-13 -3.6521000E-13 -1.1227654E-11 -6.1546052E-12 A10 -1.1255228E-14 9.5855066E-14 -4.7319549E-13 -1.4800355E-13 A11 -1.3356777E-16 3.4549322E-15 -3.5827886E-14 -1.5192364E-13 A12 1.4258719E-18 -4.3471812E-16 5.4467209E-15 8.6771151E-15 A13 1.5639491E-19 -9.3646743E-18 -4.8502167E-17 -7.7745523E-17 A14 8.6156315E-22 -2.4288844E-19 4.1016731E-18 1.4876706E-17 A15 4.2848552E-22 -4.0236340E-21 1.0234036E-17 -8.8174928E-19 A16 3.7687315E-24 8.4275321E-22 -1.9589146E-19 1.3835539E-19 A17 9.3996431E-27 1.2901333E-22 -7.1491976E-20 1.2555679E-20 A18 -2.5048230E-26 7.6982379E-24 -6.2998892E-21 -3.5708424E-21 A19 -2.1254150E-28 -1.9403331E-25 7.3416388E-22 1.3642413E-22 A20 1.1592535E-29 -2.6640315E-26 -1.2632461E-23 1.0968607E-25

[0569] Sn 20 21 KA 1.0000000E+00 1.0000000E+00 A3 -9.4700613E-05 -9.0762753E-05 A4 -1.4556393E-04 -1.4152999E-04 A5 -9.1588158E-07 -2.1058444E-06 A6 9.7254012E-08 3.8537899E-07 A7 -7.7556718E-09 -2.1407061E-09 A8 2.7876710E-09 2.0804518E-09 A9 3.6904647E-11 -1.4343878E-11 A10 -2.2000626E-11 -1.9861973E-11 A11 3.2184876E-13 2.7878988E-13 A12 5.7262599E-14 5.3994670E-14 A13 -2.3587219E-16 -3.5086583E-16 A14 -1.8127331E-16 4.0686737E-17 A15 -2.8371665E-18 1.2910113E-17 A16 -1.5196594E-19 -4.8220166E-18 A17 -1.2919810E-20 6.9704674E-20 A18 4.1166223E-21 4.4320791E-20 A19 5.8014139E-22 -3.2773064E-21 A20 -4.2307814E-23 6.9317114E-23

[0570] [Example 12]

[0571] A cross-sectional view of the structure of the imaging lens of Example 12 is shown in Fig.25 . The imaging lens of Example 12 includes, in order from the object side to the image side, a front group GF having a negative optical power, an aperture stop St, and a rear group GR having a positive optical power. The rear group GR includes a single focusing lens group Gf having a positive optical power.

[0572] The front group GF includes, in order from the object side to the image side, six lenses L11 to L16. The rear group GR includes, in order from the object side to the image side, six lenses L21 to L26. The single focusing lens group Gf includes five lenses L21 to L25. When focusing from an infinite object to the nearest object, the single focusing lens group Gf moves toward the object side, and the other lenses and the aperture stop St are fixed with respect to the image plane Sim.

[0573] Regarding the imaging lens of Example 12, the basic lens data is shown in Table 45, the specifications are shown in Table 46, the variable surface intervals are shown in Table 47, the aspherical coefficients are shown in Table 48, and the aberration diagrams are shown in Fig.26 .

[0574] [Table 45]

[0575] Example 12

[0576]

[0577] [Table 46]

[0578] Example 12

[0579] f 16.32 Bf 13.82 FNo. 1.85 2ωm[°] 109.4

[0580] [Table 47] Example 12

[0581] Infinity |β|＝0.1 DD12 2.4998 0.0124 DD21 2.4221 3.4871

[0582] [Table 48]

[0583] Example 12

[0584] Sn 1 2 10 11 KA 1.0000000E+00 4.0600000E-01 1.0000000E+00 1.0000000E+00 A3 4.5232350E-04 4.8807605E-04 -1.6333698E-05 -2.3990220E-05 A4 -1.1505587E-05 -1.0910981E-05 -2.3944015E-05 -6.8637933E-06 A5 8.9741596E-09 7.5199156E-07 -8.3199939E-07 -3.1585063E-07 A6 -2.3501012E-09 1.7615702E-09 2.0655408E-08 -7.1801835E-08 A7 2.7283474E-10 -2.7306000E-09 -2.5288936E-09 2.9033867E-09 A8 1.0146514E-11 1.4859706E-10 -1.7740277E-10 8.2705340E-11 A9 -4.6394309E-14 -8.0693345E-13 -2.7549009E-12 -2.8518606E-12 A10 -1.5773352E-14 2.0275962E-14 -7.7343520E-13 -5.2793685E-13 A11 -1.5293005E-16 5.8125941E-15 5.0896736E-15 -1.2602974E-13 A12 8.3984797E-19 -1.5034560E-17 2.8069244E-15 7.5091702E-15 A13 1.0630012E-19 -3.3960491E-17 -5.2242331E-16 -1.9280424E-16 A14 1.0137667E-20 -2.3074784E-19 6.6688281E-17 2.4470643E-17 A15 1.9266033E-22 1.7617927E-20 4.7656940E-18 -8.7463844E-19 A16 4.3960134E-24 1.0880713E-21 -1.9800256E-19 1.1145318E-19 A17 -1.8230574E-25 1.1177665E-22 -4.5129052E-20 1.2646710E-20 A18 -1.1832001E-26 1.1132354E-23 -5.1165304E-21 -3.2387893E-21 A19 -4.8057536E-28 -6.3848685E-25 7.2216178E-22 1.4604767E-22 A20 1.6906452E-29 -1.9681913E-26 -1.9238815E-23 -1.3488175E-24

[0585] Sn 20 21 KA 1.0000000E+00 1.0000000E+00 A3 -7.6025872E-05 -8.5475570E-05 A4 -1.5813327E-04 -1.5074950E-04 A5 4.9909617E-08 -1.8798278E-06 A6 7.1748522E-08 4.2114308E-07 A7 -6.8913602E-09 -2.6615111E-09 A8 3.0054963E-09 2.0070691E-09 A9 1.7890383E-11 -2.0228420E-11 A10 -2.2585619E-11 -1.9623695E-11 A11 3.0899085E-13 2.4071797E-13 A12 6.1890995E-14 5.8834618E-14 A13 -4.1303888E-16 -4.7371825E-16 A14 -1.3489412E-16 4.0815959E-17 A15 -5.1078032E-18 1.4349849E-17 A16 -1.5998196E-19 -4.9200511E-18 A17 -1.9007015E-20 6.3611453E-20 A18 4.4535045E-21 4.4318403E-20 A19 6.0011630E-22 -3.2103953E-21 A20 -4.3635055E-23 6.6624691E-23

[0586] [Example 13]

[0587] The cross-sectional view of the structure of the imaging lens of Example 13 is shown in Fig. 27 . The imaging lens of Example 13 includes, in order from the object side to the image side, a front group GF with a negative optical power, an aperture stop St, and a rear group GR with a positive optical power. The rear group GR includes a single focusing lens group Gf with a positive optical power.

[0588] The front group GF includes, in order from the object side to the image side, 6 lenses L11 to L16. The rear group GR includes, in order from the object side to the image side, 6 lenses L21 to L26. The single focusing lens group Gf includes 5 lenses L21 to L25. When focusing from an infinite object to the nearest object, the single focusing lens group Gf moves toward the object side, and the other lenses and the aperture stop St are fixed relative to the image plane Sim.

[0589] Regarding the imaging lens of Example 13, the basic lens data is shown in Table 49, the specifications are shown in Table 50, the variable surface intervals are shown in Table 51, the aspherical coefficients are shown in Table 52, and the aberration diagrams are shown in Fig.28 .

[0590] [Table 49]

[0591] Example 13

[0592]

[0593] [Table 50]

[0594] Example 13

[0595] f 16.32 Bf 14.63 FNo. 1.85 2ωm[°] 109.4

[0596] [Table 51] Example 13

[0597] Infinity |β|＝0.1 DD12 2.4998 0.0124 DD21 0.9998 3.4871

[0598] [Table 52]

[0599] Example 13

[0600] Sn 1 2 10 11 KA 1.0000000E+00 4.0600000E-01 1.0000000E+00 1.0000000E+00 A3 6.0192899E-04 6.8940099E-04 -5.5038664E-06 -3.2159631E-05 A4 -1.4588781E-05 -1.7716805E-05 -2.7652004E-05 -4.8675134E-06 A5 -9.9997227E-08 1.0432595E-06 -4.9459591E-07 -5.2646102E-07 A6 -2.1530404E-09 1.0804153E-08 1.1713143E-08 -7.7699212E-08 A7 3.7314161E-10 -3.6266840E-09 -4.0871132E-09 4.0614874E-09 A8 1.1559300E-11 1.2379685E-10 -2.3209944E-10 1.0000855E-10 A9 3.4413025E-14 1.4071265E-13 -1.9645632E-12 -1.4662928E-11 A10 -1.6525556E-14 -8.5985927E-14 1.0684085E-12 -5.6527118E-14 A11 -2.4637386E-16 6.6477238E-15 -1.1959443E-13 -1.2149859E-13 A12 -6.8396282E-18 2.8419221E-18 4.3205725E-15 9.3531715E-15 A13 -3.0337044E-20 1.4924379E-17 -5.4741691E-16 -3.0653895E-16 A14 9.2749959E-21 -2.7774564E-20 8.3774367E-18 4.5988409E-18 A15 5.0709486E-22 -3.0234931E-20 9.5556470E-18 3.8132633E-19 A16 1.3673423E-23 -4.4210455E-21 -9.7902912E-20 1.6351115E-19 A17 6.9250594E-26 1.2680044E-22 -5.1955667E-20 9.7020719E-21 A18 -1.9747462E-26 -2.0164112E-24 -5.9008609E-21 -3.5670432E-21 A19 -2.9531686E-28 -4.7947023E-25 7.6511916E-22 1.8021407E-22 A20 5.3384565E-31 -3.0406963E-26 -2.0532528E-23 -2.4125994E-24

[0601] Sn 20 21 KA 1.0000000E+00 1.0000000E+00 A3 -2.7037171E-04 -2.8998906E-04 A4 -1.3534581E-04 -1.2478663E-04 A5 -1.4810726E-07 -2.2703423E-06 A6 4.7066131E-08 4.0326531E-07 A7 -6.2317351E-09 -2.4916314E-09 A8 3.1002213E-09 2.1591277E-09 A9 3.6997325E-11 -5.7560460E-12 A10 -2.1543373E-11 -1.9680972E-11 A11 2.9414135E-13 2.4998682E-13 A12 5.8414727E-14 5.3051485E-14 A13 -7.4398209E-16 -7.1805999E-16 A14 -2.0743254E-16 4.0604524E-17 A15 -7.2016010E-18 1.3021754E-17 A16 7.9547945E-20 -4.7687364E-18 A17 -1.0403490E-21 7.2598517E-20 A18 5.4679231E-21 4.4134603E-20 A19 6.2165732E-22 -3.2073406E-21 A20 -5.0447895E-23 6.5211684E-23

[0602] [Example 14]

[0603] A cross-sectional view of the structure of the imaging lens of Example 14 is shown in Fig.29 . The imaging lens of Example 14 includes, in order from the object side to the image side, a front group GF having a negative optical power, an aperture stop St, and a rear group GR having a positive optical power. The rear group GR includes a single focusing lens group Gf having a positive optical power.

[0604] The front group GF includes, in order from the object side to the image side, six lenses L11 to L16. The rear group GR includes, in order from the object side to the image side, seven lenses L21 to L27. The single focusing lens group Gf includes six lenses L21 to L26. When focusing from an infinitely distant object to the nearest object, the single focusing lens group Gf moves toward the object side, and the other lenses and the aperture stop St are fixed relative to the image plane Sim.

[0605] Regarding the imaging lens of Example 14, the basic lens data is shown in Table 53, the specifications are shown in Table 54, the variable surface intervals are shown in Table 55, the aspherical coefficients are shown in Table 56, and the various aberration diagrams are shown in Fig.30 .

[0606] [Table 53]

[0607] Example 14

[0608]

[0609] [Table 54]

[0610] Example 14

[0611] f 16.32 Bf 13.57 FNo. 1.85 2ωm[°] 109.4

[0612] [Table 55] Example 14

[0613] Infinity |β|＝0.1 DD12 2.4998 0.1866 DD23 1.5264 3.8396

[0614] [Table 56]

[0615] Example 14

[0616] Sn 1 2 10 11 KA 1.0000000E+00 4.0600000E-01 1.0000000E+00 1.0000000E+00 A3 4.7684322E-04 4.9787964E-04 -2.6681643E-05 -1.6231088E-05 A4 -7.9470781E-06 -2.7773731E-06 -1.4818741E-05 -4.2962041E-06 A5 -2.4144877E-07 2.3785703E-07 -1.0561681E-06 -1.3596209E-07 A6 -1.8479289E-09 1.9551733E-08 3.4244577E-08 -7.7712682E-08 A7 2.7243704E-10 -2.6884188E-09 -1.5038680E-09 2.7900995E-09 A8 1.4911698E-11 1.3582503E-10 -2.3323683E-10 1.0299671E-10 A9 1.2254642E-13 -5.9728746E-13 -7.2754880E-12 -4.2473979E-12 A10 -1.2478837E-14 -1.2836901E-14 2.8280673E-13 -4.7832049E-13 A11 -2.9514773E-16 4.2582725E-15 1.7734089E-14 -1.2116950E-13 A12 -5.5410546E-18 -1.0618901E-16 1.2461776E-15 5.8746775E-15 A13 -1.8913251E-19 6.5536432E-19 -6.0232282E-16 -9.8680586E-17 A14 4.9967010E-21 -3.2743558E-19 1.5141365E-17 1.6660649E-17 A15 1.9248874E-22 4.7503534E-21 7.3614356E-18 4.4970748E-19 A16 1.8089945E-24 1.2648963E-21 -1.5137873E-19 -9.5858010E-21 A17 5.9552446E-25 1.1863209E-22 -5.2745172E-20 1.1603316E-20 A18 -3.4043737E-27 7.8822311E-24 -3.2995122E-21 -2.4217908E-21 A19 -4.0868625E-28 -4.3548903E-25 6.5249173E-22 1.1265901E-22 A20 -9.3277096E-30 -3.3928512E-26 -2.0331686E-23 -1.3216017E-24

[0617] Sn 22 23 KA 1.0000000E+00 1.0000000E+00 A3 2.6556343E-05 2.2391567E-05 A4 -1.9333813E-04 -1.8554098E-04 A5 -2.5688216E-06 -4.3523553E-06 A6 5.8647007E-08 4.0214564E-07 A7 -2.8449668E-09 3.2021529E-09 A8 3.4158234E-09 2.6880653E-09 A9 2.9074208E-11 2.5235082E-11 A10 -2.3547915E-11 -1.9807165E-11 A11 2.8544137E-13 3.1056410E-14 A12 6.9433976E-14 4.4056488E-14 A13 -2.1651289E-16 -1.6730377E-16 A14 -1.0492692E-16 3.7272017E-17 A15 -3.7984684E-19 -3.2660425E-18 A16 1.9442472E-19 -1.4999772E-19 A17 -7.8277737E-20 3.8054601E-22 A18 -2.8648139E-22 3.2201142E-22 A19 5.4854045E-22 -1.9270422E-23 A20 -1.9621774E-23 9.4483060E-25

[0618] [Example 15]

[0619] The cross-sectional view of the structure of the imaging lens of Example 15 is shown in Fig.31 . The imaging lens of Example 15 includes, in order from the object side to the image side, a front group GF having a negative optical power, an aperture stop St, and a rear group GR having a positive optical power. The rear group GR includes a single focusing lens group Gf having a positive optical power.

[0620] The front group GF includes, in order from the object side to the image side, six lenses L11 to L16. The rear group GR includes, in order from the object side to the image side, seven lenses L21 to L27. The single focusing lens group Gf includes six lenses L21 to L26. When focusing from an infinitely distant object to the nearest object, the single focusing lens group Gf moves toward the object side, and the other lenses and the aperture stop St are fixed with respect to the image plane Sim.

[0621] Regarding the imaging lens of Example 15, the basic lens data is shown in Table 57, the specifications are shown in Table 58, the variable surface intervals are shown in Table 59, the aspherical coefficients are shown in Table 60, and the aberration diagrams are shown in Fig.32 .

[0622] [Table 57]

[0623] Example 15

[0624]

[0625] [Table 58]

[0626] Example 15

[0627] f 16.32 Bf 13.40 FNo. 1.85 2ωm[°] 109.4

[0628] [Table 59]

[0629] Example 15

[0630] Infinity |β|＝0.1 DD12 2.4998 0.1629 DD23 1.4058 3.7426

[0631] [Table 60]

[0632] Example 15

[0633] Sn 1 2 10 11 KA 1.0000000E+00 4.0600000E-01 1.0000000E+00 1.0000000E+00 A3 4.8723836E-04 5.0353743E-04 -2.6467214E-05 -1.5903084E-05 A4 -1.2750284E-05 -9.1959133E-06 -1.4372871E-05 -3.6606693E-06 A5 -7.8232607E-09 4.8281644E-07 -1.2144489E-06 -1.1666677E-07 A6 -3.1300233E-09 1.5197672E-08 4.0308307E-08 -7.4102360E-08 A7 2.6120536E-10 -2.8674437E-09 -8.9764096E-10 2.4915507E-09 A8 1.0663564E-11 1.4670695E-10 -1.1989362E-10 4.4393605E-11 A9 5.2598770E-14 -1.6041942E-12 -1.9105583E-11 2.5006887E-12 A10 -1.1357059E-14 2.6138562E-14 -2.1515201E-13 -5.4695096E-13 A11 -1.6665716E-16 1.1674319E-15 3.2731476E-14 -1.2579414E-13 A12 -4.4708879E-1 8 -6.6580771E-17 1.2746344E-15 6.0551472E-15 A13 -5.0995604E-20 2.8582317E-18 -5.8350131E-16 -1.3456805E-16 A14 2.9980942E-21 2.3899478E-20 4.8967940E-17 2.0304170E-17 A15 1.8656226E-22 -1.3030730E-20 7.9529683E-18 3.6646253E-19 A16 3.0881343E-24 1.0837184E-21 -2.0076489E-19 -6.2991865E-20 A17 3.3105225E-25 7.8926959E-23 -5.4019890E-20 1.6162201E-20 A18 -2.1597925E-27 6.4301239E-24 -4.8609688E-21 -2.4796721E-21 A19 -5.0857879E-28 -5.7455853E-25 6.7197675E-22 1.1328299E-22 A20 7.3007446E-31 -1.6895561E-26 -1.5928188E-23 -1.4657078E-24

[0634] Sn 22 23 KA 1.0000000E+00 1.0000000E+00 A3 -1.7006477E-05 -2.8054293E-05 A4 -1.9289139E-04 -1.8332140E-04 A5 -2.4762768E-06 -4.6083063E-06 A6 2.4293443E-08 4.0644276E-07 A7 -2.3889458E-09 3.2962588E-09 A8 3.3414468E-09 2.8418715E-09 A9 6.0974643E-11 2.2181172E-11 A10 -2.4737766E-11 -2.1388165E-11 A11 2.1250747E-13 7.3417597E-14 A12 6.1767428E-14 4.4786168E-14 A13 3.0510452E-16 -1.7040574E-18 A14 -9.1824663E-17 4.0230947E-17 A15 -1.6621526E-19 -3.4230016E-18 A16 4.9524080E-20 -1.4762148E-19 A17 -5.5776289E-20 8.2622551E-22 A18 4.3859948E-22 -1.2278556E-22 A19 4.1596921E-22 9.0836099E-24 A20 -1.8737113E-23 4.2184521E-25

[0635] [Example 16]

[0636] The cross-sectional view of the structure of the imaging lens of Example 16 is shown in Fig.33 . The imaging lens of Example 16 includes, in order from the object side to the image side, a front group GF with a negative optical power, an aperture stop St, and a rear group GR with a positive optical power. The rear group GR includes a single focusing lens group Gf with a positive optical power.

[0637] The front group GF includes six lenses L11 to L16 in order from the object side to the image side. The rear group GR includes seven lenses L21 to L27 in order from the object side to the image side. The single focusing lens group Gf includes six lenses L21 to L26. When focusing from an infinite object to the nearest object, the single focusing lens group Gf moves toward the object side, and the other lenses and the aperture stop St are fixed with respect to the image plane Sim.

[0638] Regarding the imaging lens of Example 16, the basic lens data is shown in Table 61, the specifications are shown in Table 62, the variable surface intervals are shown in Table 63, the aspherical coefficients are shown in Table 64, and the various aberration diagrams are shown in Fig.34 .

[0639] [Table 61]

[0640] Example 16

[0641]

[0642] [Table 62]

[0643] Example 16

[0644] f 16.32 Bf 13.45 FNo. 1.85 2ωm[°] 109.4

[0645] [Table 63] Example 16

[0646] Infinity |β|＝0.1 DD12 2.4999 0.1887 DD23 1.6673 3.9785

[0647] [Table 64]

[0648] Example 16

[0649] Sn 1 2 10 11 KA 1.0000000E+00 4.0600000E-01 1.0000000E+00 1.0000000E+00 A3 4.8178902E-04 5.0358084E-04 -2.4368695E-05 -1.7313228E-05 A4 -8.2195019E-06 -3.8560620E-06 -1.5128595E-05 -3.9668194E-06 A5 -2.2977486E-07 3.9603030E-07 -1.0387449E-06 -1.6063178E-07 A6 -3.2449230E-09 1.4825315E-08 3.6243845E-08 -7.8947174E-08 A7 2.8060426E-10 -3.2468386E-09 -1.6294220E-09 3.0458403E-09 A8 1.4502183E-11 1.6789122E-10 -2.4264244E-10 1.0565471E-10 A9 1.2471334E-13 -4.1133959E-13 -8.1952462E-12 -3.7604158E-12 A10 -1.2656947E-14 -7.8201123E-14 4.9144451E-13 -4.6574350E-13 A11 -2.5192004E-16 2.0389109E-15 2.7123768E-14 -1.2678234E-13 A12 -6.7886351E-18 2.2935836E-17 6.7987897E-16 5.4290550E-15 A13 -1.8812068E-19 2.9267556E-18 -6.1486712E-16 -4.6233710E-17 A14 4.6549511E-21 -1.8297264E-19 1.0264578E-17 1.6871566E-17 A15 2.3942899E-22 4.2657952E-22 7.5395651E-18 4.9935237E-19 A16 7.5056272E-24 1.0076554E-21 -1.5077655E-19 -1.1470052E-20 A17 5.9660107E-25 1.0513073E-22 -5.0515498E-20 1.1353184E-20 A18 -1.3356802E-26 7.0170601E-24 -3.3668419E-21 -2.4438741E-21 A19 -3.2336444E-28 -6.1681868E-25 6.5711731E-22 1.1475791E-22 A20 -6.0769944E-30 -2.2154890E-26 -2.0628500E-23 -1.3513760E-24

[0650] Sn 22 23 KA 1.0000000E+00 1.0000000E+00 A3 -1.7586299E-05 -2.3954262E-05 A4 -1.8678763E-04 -1.7919540E-04 A5 -3.0294125E-06 -4.6565704E-06 A6 5.6351004E-08 3.7859039E-07 A7 -2.6617580E-09 3.6716085E-09 A8 3.3502732E-09 2.7414651E-09 A9 2.9486229E-11 2.6868793E-11 A10 -2.3376235E-11 -1.9864852E-11 A11 2.8653558E-13 3.4341384E-14 A12 7.1045987E-14 4.3749885E-14 A13 -1.5471132E-16 -1.4926763E-16 A14 -1.0182286E-16 3.4003334E-17 A15 -5.6637796E-19 -3.0558168E-18 A16 1.2589173E-19 -1.4127206E-19 A17 -7.8246208E-20 -1.7394097E-22 A18 -4.5831365E-22 2.4951609E-22 A19 5.6925563E-22 -1.8428377E-23 A20 -1.9633374E-23 1.1040589E-24

[0651] [Example 17]

[0652] The cross-sectional view of the structure of the imaging lens of Example 17 is shown in Fig.35In the imaging lens of Embodiment 17, a front group GF having a negative optical power, an aperture stop St, and a rear group GR having a positive optical power are sequentially included from the object side to the image side. The rear group GR includes a single focusing lens group Gf having a positive optical power.

[0653] The front group GF sequentially includes seven lenses L11 to L17 from the object side to the image side. The rear group GR sequentially includes seven lenses L21 to L27 from the object side to the image side. The single focusing lens group Gf includes six lenses L21 to L26. When focusing from an infinitely distant object to the nearest object, the single focusing lens group Gf moves toward the object side, and the other lenses and the aperture stop St are fixed with respect to the image plane Sim.

[0654] Regarding the imaging lens of Embodiment 17, the basic lens data is shown in Table 65, the specifications are shown in Table 66, the variable surface intervals are shown in Table 67, the aspherical coefficients are shown in Table 68, and the aberration diagrams are shown in Fig.36 in.

[0655] [Table 65]

[0656] Embodiment 17

[0657]

[0658] [Table 66]

[0659] Embodiment 17

[0660] f 14.32 Bf 13.80 FNo. 1.83 2ωm[°] 116.2

[0661] [Table 67] Embodiment 17

[0662] Infinity |β|＝0.1 DD14 2.5000 0.2093 DD25 0.9998 3.2905

[0663] [Table 68]

[0664] Embodiment 17

[0665] Sn 1 2 12 13 KA 1.0000000E+00 4.0600000E-01 1.0000000E+00 1.0000000E+00 A3 4.1262266E-04 4.9988012E-04 -2.3265838E-05 -3.1694256E-05 A4 -7.1419475E-06 -2.0379692E-05 -1.7330369E-05 -3.0035647E-06 A5 -4.3269763E-09 1.6278755E-06 -1.0661802E-06 -5.8495160E-07 A6 -5.0099856E-09 -1.8336032E-08 2.4034190E-08 -7.7086063E-08 A7 1.5157390E-10 -4.4814384E-09 -1.0907473E-09 3.5509362E-09 A8 8.2997571E-12 1.5880790E-10 -3.0296019E-10 4.6347777E-11 A9 7.1856122E-14 1.1530196E-12 -1.0637347E-11 -3.8515601E-12 A10 -9.5575777E-15 5.9358362E-14 5.0479010E-13 -3.8368169E-13 A11 -5.1796272E-17 4.3294018E-15 1.1005562E-14 -1.1818262E-13 A12 -1.4576481E-18 -1.9285238E-16 2.7663894E-15 5.0983119E-15 A13 -2.3063451E-20 -5.3966555E-18 -5.2758884E-16 6.8147996E-18 A14 2.6692392E-21 -8.0693491E-19 1.8723428E-17 2.3658203E-17 A15 1.5601354E-22 -2.7735972E-20 7.7010503E-18 1.4473892E-18 A16 2.2303957E-24 3.9859311E-22 -1.5610213E-19 -8.8467156E-20 A17 -1.5241235E-26 9.7468103E-23 -5.5244481E-20 5.2268944E-21 A18 -4.1548416E-27 7.4068816E-24 -3.5692666E-21 -2.2930371E-21 A19 -1.2199570E-28 -1.7429863E-25 6.7057028E-22 1.2397676E-22 A20 3.6672277E-30 -1.0898692E-26 -1.9421536E-23 -1.0361141E-24

[0666] Sn 24 25 KA 1.0000000E+00 1.0000000E+00 A3 -9.2874503E-05 -6.7559343E-05 A4 -1.5045275E-04 -1.5234700E-04 A5 -2.9745516E-06 -3.5530059E-06 A6 7.2533638E-08 3.3076416E-07 A7 9.5071513E-10 4.7206791E-09 A8 3.5313721E-09 2.7840047E-09 A9 4.3013061E-11 2.2634473E-11 A10 -2.4948328E-11 -2.0974307E-11 A11 1.5581054E-13 4.8632274E-15 A12 6.6860168E-14 4.2658444E-14 A13 -4.9872354E-16 -1.0578259E-16 A14 -1.1219734E-16 3.2677364E-17 A15 -1.4423039E-18 -2.9369533E-18 A16 2.6129255E-19 -5.9557022E-20 A17 -5.6226812E-20 4.1737927E-21 A18 8.5665911E-22 1.5999524E-23 A19 5.3123900E-22 -2.4809304E-23 A20 -2.4874019E-23 9.7239769E-25

[0667] [Embodiment 18]

[0668] A cross-sectional view of the structure of the imaging lens of Embodiment 18 is shown in Fig.37 in. The imaging lens of Embodiment 18 sequentially includes a front group GF having a negative optical power, an aperture stop St, and a rear group GR having a positive optical power from the object side to the image side. The rear group GR includes a single focusing lens group Gf having a positive optical power.

[0669] The front group GF includes seven lenses L11 to L17 in order from the object side to the image side. The rear group GR includes seven lenses L21 to L27 in order from the object side to the image side. The single focusing lens group Gf includes six lenses L21 to L26. When focusing from an infinitely distant object to the nearest object, the single focusing lens group Gf moves toward the object side, and the other lenses and the aperture stop St are fixed relative to the image plane Sim.

[0670] Regarding the imaging lens of Embodiment 18, the basic lens data is shown in Table 69, the specifications are shown in Table 70, the variable surface intervals are shown in Table 71, the aspherical coefficients are shown in Table 72, and the aberration diagrams are shown in Fig.38 .

[0671] [Table 69]

[0672] Embodiment 18

[0673]

[0674] [Table 70]

[0675] Embodiment 18

[0676] f 14.32 Bf 13.75 FNo. 1.85 2ωm[°] 116.2

[0677] [Table 71]

[0678] Embodiment 18

[0679] Infinity |β|＝0.1 DD14 2.9956 0.7697 DD25 1.3009 3.5267

[0680] [Table 72]

[0681] Embodiment 18

[0682] Sn 1 2 12 13 KA 1.0000000E+00 4.0600000E-01 1.0000000E+00 1.0000000E+00 A3 1.6736897E-04 2.4790933E-04 -8.3758769E-06 -3.0982108E-05 A4 1.2993900E-06 -1.0462567E-05 -2.5042296E-05 -2.7366538E-06 A5 -2.5032639E-08 1.1977349E-06 -7.9803913E-07 -5.7510787E-07 A6 -6.6041799E-09 -1.6956090E-08 2.7795172E-08 -7.7216517E-08 A7 1.0923673E-10 -4.0305710E-09 -1.5327036E-09 3.1907078E-09 A8 8.2739053E-12 1.7223607E-10 -3.3072332E-10 1.1768418E-10 A9 8.8562284E-14 1.6431968E-12 -1.1759483E-11 -9.7249273E-12 A10 -8.3917653E-15 8.8948397E-15 6.6115846E-13 -8.0611077E-13 A11 -6.7519578E-17 3.0129613E-15 -6.5520680E-14 -1.0289776E-13 A12 -7.7666666E-19 -2.3406427E-16 4.5130679E-15 5.3465004E-15 A13 -1.8550707E-20 -4.8615687E-18 -5.5691686E-16 -5.8217394E-17 A14 2.3591278E-21 -8.3212854E-19 5.1442192E-17 2.6720572E-17 A15 1.4026366E-22 -2.5727501E-20 7.7981046E-18 2.5970841E-19 A16 2.2814064E-24 9.5075430E-22 -2.8559768E-19 -1.2514608E-20 A17 -1.9400466E-26 1.0793652E-22 -4.8469335E-20 1.0975012E-20 A18 -4.1536818E-27 7.7739918E-24 -5.4187554E-21 -2.6622522E-21 A19 -1.1586517E-28 -1.7824978E-25 6.8395963E-22 1.0255270E-22 A20 3.6168265E-30 -1.2662080E-26 -1.5263475E-23 1.6020861E-26

[0683] Sn 24 25 KA 1.0000000E+00 1.0000000E+00 A3 -1.2882845E-04 -7.9648813E-05 A4 -1.3964183E-04 -1.4079877E-04 A5 -3.4999033E-06 -3.4994672E-06 A6 8.6966018E-08 3.3086063E-07 A7 1.0331883E-09 2.9579832E-09 A8 3.4268136E-09 2.7571702E-09 A9 4.3732751E-11 2.2939217E-11 A10 -2.5399994E-11 -2.0886606E-11 A11 1.4910271E-13 9.4501874E-15 A12 6.8176379E-14 4.3014724E-14 A13 -5.2951530E-16 -1.4108587E-16 A14 -9.8114594E-17 3.6335556E-17 A15 -1.4913391E-18 -2.7734574E-18 A16 3.5427442E-19 -5.9227523E-20 A17 -5.9471941E-20 3.9287534E-21 A18 6.1468466E-22 3.7291322E-23 A19 5.3977253E-22 -3.0474841E-23 A20 -2.5664360E-23 1.0757625E-24

[0684] [Embodiment 19]

[0685] A cross-sectional view of the structure of the imaging lens of Embodiment 19 is shown in Fig.39 . The imaging lens of Embodiment 19 includes a front group GF having a negative focal power, an aperture stop St, and a rear group GR having a positive focal power in order from the object side to the image side. The rear group GR includes a single focusing lens group Gf having a positive focal power.

[0686] The front lens group GF includes seven lenses L11 to L17 in order from the object side to the image side. The rear lens group GR includes seven lenses L21 to L27 in order from the object side to the image side. The single focusing lens group Gf includes six lenses L21 to L26. When focusing from an infinitely distant object to the nearest object, the single focusing lens group Gf moves toward the object side, and the other lenses and the aperture stop St are fixed with respect to the image plane Sim.

[0687] Regarding the imaging lens of Embodiment 19, the basic lens data is shown in Table 73, the specifications are shown in Table 74, the variable surface intervals are shown in Table 75, the aspherical coefficients are shown in Table 76, and the aberration diagrams are shown in Fig.40 in.

[0688] [Table 73]

[0689] Embodiment 19

[0690]

[0691] [Table 74]

[0692] Embodiment 19

[0693] f 14.32 Bf 14.07 FNo. 1.85 2ωm[°] 116.2

[0694] [Table 75] Embodiment 19

[0695] Infinity |β|＝0.1 DD14 2.4998 0.2420 DD25 1.0516 3.3094

[0696] [Table 76]

[0697] Embodiment 19

[0698] Sn 1 2 12 13 KA 1.0000000E+00 4.0600000E-01 1.0000000E+00 1.0000000E+00 A3 2.3695648E-04 3.3564320E-04 -1.0159972E-05 -2.9992971E-05 A4 -3.2324991E-07 -1.3810300E-05 -2.0928448E-05 -3.6119121E-06 A5 -4.7221803E-08 1.4132508E-06 -9.1052510E-07 -6.1050006E-07 A6 -6.4290689E-09 -2.0839598E-08 3.1026505E-08 -7.6518734E-08 A7 1.2032942E-10 -4.1895156E-09 -1.9408387E-09 3.6138597E-09 A8 8.9981149E-12 1.7609031E-10 -3.2860580E-10 3.5412629E-11 A9 8.2724393E-14 1.0878442E-12 -1.4047804E-11 -7.3774928E-12 A10 -9.5315372E-15 3.0549951E-14 2.3670629E-13 -5.3353730E-13 A11 -4.9415720E-17 2.9205476E-15 4.9407213E-14 -1.1496998E-13 A12 -1.1696626E-18 -2.0781404E-16 2.5920002E-15 5.0693952E-15 A13 -2.0816969E-20 -4.3219981E-18 -5.5526777E-16 9.9789660E-17 A14 2.4710734E-21 -7.5261386E-19 2.3971624E-17 2.0828585E-17 A15 1.4652651E-22 -2.6001427E-20 6.5916091E-18 6.1170703E-19 A16 2.1394477E-24 5.2069816E-22 -2.1507344E-19 -7.2029156E-20 A17 -1.4990618E-26 1.0021385E-22 -5.6091173E-20 1.1689351E-20 A18 -4.2332351E-27 7.5182184E-24 -3.4163767E-21 -2.6560829E-21 A19 -1.1888076E-28 -1.7588409E-25 6.9014080E-22 1.1694428E-22 A20 3.6894220E-30 -1.1789885E-26 -2.0347913E-23 -4.7962342E-25

[0699] Sn 24 25 KA 1.0000000E+00 1.0000000E+00 A3 -1.3061861E-04 -9.0432441E-05 A4 -1.3109013E-04 -1.3369853E-04 A5 -3.0638811E-06 -3.1061841E-06 A6 1.0617416E-07 3.2947750E-07 A7 1.1177044E-09 2.3302984E-09 A8 3.4100745E-09 2.7117487E-09 A9 3.8380824E-11 2.1184154E-11 A10 -2.5423696E-11 -2.0907705E-11 A11 1.4042549E-13 9.8405526E-15 A12 6.6482100E-14 4.2655731E-14 A13 -3.7228740E-16 -1.3151797E-16 A14 -1.0782550E-16 3.6491653E-17 A15 -1.0976822E-18 -2.7111422E-18 A16 3.2737026E-19 -6.3422852E-20 A17 -6.0607257E-20 3.8349409E-21 A18 7.9069117E-22 6.9471821E-23 A19 5.4079341E-22 -2.7745357E-23 A20 -2.5262563E-23 9.2198598E-25

[0700] [Embodiment 20]

[0701] A cross-sectional view of the structure of the imaging lens of Embodiment 20 is shown in Fig.41 in. The imaging lens of Embodiment 20 includes a front lens group GF having a negative refractive power, an aperture stop St, and a rear lens group GR having a positive refractive power in order from the object side to the image side. The rear lens group GR includes a single focusing lens group Gf having a positive refractive power.

[0702] The front group GF includes seven lenses L11 to L17 in order from the object side to the image side. The rear group GR includes seven lenses L21 to L27 in order from the object side to the image side. The single-focus lens group Gf includes six lenses L21 to L26. When focusing from an infinitely distant object to the nearest object, the single-focus lens group Gf moves toward the object side, and the other lenses and the aperture stop St are fixed relative to the image plane Sim.

[0703] Regarding the imaging lens of Embodiment 20, the basic lens data is shown in Table 77, the specifications are shown in Table 78, the variable surface intervals are shown in Table 79, the aspherical coefficients are shown in Table 80, and the aberration diagrams are shown in Fig.42 it.

[0704] [Table 77]

[0705] Embodiment 20

[0706]

[0707] [Table 78]

[0708] Embodiment 20

[0709] f 14.32 Bf 13.77 FNo. 1.85 2ωm[°] 116.2

[0710] [Table 79] Embodiment 20

[0711] Infinity |β|＝0.1 DD14 2.4999 0.2449 DD25 1.0295 3.2844

[0712] [Table 80]

[0713] Embodiment 20

[0714] Sn 1 2 12 13 KA 1.0000000E+00 4.0600000E-01 1.0000000E+00 1.0000000E+00 A3 2.7110108E-04 3.5719178E-04 -1.6024418E-05 -2.9517250E-05 A4 -2.5220827E-06 -1.5204327E-05 -2.0679615E-05 -2.8242817E-06 A5 -4.6414563E-09 1.3767540E-06 -9.9518539E-07 -6.1658140E-07 A6 -6.3724392E-09 -1.9725977E-08 2.9305696E-08 -8.0227108E-08 A7 1.1905767E-10 -4.1941209E-09 -2.8293557E-09 2.6349394E-09 A8 8.5208445E-12 1.7288962E-10 -3.0132497E-10 2.0631438E-11 A9 9.1838747E-14 1.0880840E-12 -1.1511977E-11 -5.3357333E-12 A10 -9.4101564E-15 2.3086106E-14 3.3279995E-13 -5.2000166E-13 A11 -5.8526453E-17 3.6110845E-15 4.2114039E-14 -8.6532876E-14 A12 -6.4804375E-19 -1.9616490E-16 3.0776675E-15 3.4288963E-15 A13 -1.7226270E-20 -6.8309188E-18 -7.5436625E-16 -2.0160312E-16 A14 2.2637672E-21 -7.8127332E-19 1.4939853E-17 3.6016806E-17 A15 1.4261108E-22 -2.6390636E-20 7.9415702E-18 1.0368411E-18 A16 1.9505865E-24 8.5450788E-22 -1.9935702E-19 -9.2406523E-20 A17 -1.4347173E-26 1.0654825E-22 -5.0356326E-20 1.1425024E-20 A18 -4.0329387E-27 7.7366467E-24 -4.0253954E-21 -2.5019908E-21 A19 -1.1420408E-28 -1.8002593E-25 7.1751924E-22 1.1111470E-22 A20 3.5097703E-30 -1.2717178E-26 -2.1465546E-23 -6.8782527E-25

[0715] Sn 24 25 KA 1.0000000E+00 1.0000000E+00 A3 -1.4901073E-04 -1.2512803E-04 A4 -1.3958653E-04 -1.3970307E-04 A5 -3.1075414E-06 -3.6165767E-06 A6 9.6709925E-08 3.5094509E-07 A7 1.0993789E-09 3.0985756E-09 A8 3.4504888E-09 2.7559386E-09 A9 4.3266878E-11 2.1495518E-11 A10 -2.5366418E-11 -2.1058499E-11 A11 1.4304357E-13 3.6944028E-15 A12 6.6126321E-14 4.2004414E-14 A13 -3.3655165E-16 -1.0268953E-16 A14 -1.0727428E-16 3.6779070E-17 A15 -1.3845650E-18 -2.6910168E-18 A16 2.7514893E-19 -6.5656984E-20 A17 -6.1639814E-20 2.9749415E-21 A18 8.7689554E-22 5.9980947E-23 A19 5.4828712E-22 -2.7628251E-23 A20 -2.5114730E-23 1.1302794E-24

[0716] [Embodiment 21]

[0717] A cross-sectional view of the structure of the imaging lens of Embodiment 21 is shown in Fig.43 it. The imaging lens of Embodiment 21 includes, in order from the object side to the image side, a front group GF having a positive refractive power, an aperture stop St, and a rear group GR having a positive refractive power. The imaging lens includes a single-focus lens group Gf.

[0718] The front group GF includes eight lenses L11 to L18 in order from the object side to the image side.

[0719] The rear group GR includes six lenses L21 to L26 in order from the object side to the image side. The single focusing lens group Gf includes lenses L17 to L18, the aperture stop St, and lenses L21 to L24. When focusing from an infinitely distant object to the nearest object, the single focusing lens group Gf moves toward the object side, and the other lenses are fixed with respect to the image plane Sim.

[0720] Regarding the imaging lens of Embodiment 21, the basic lens data is shown in Table 81, the specifications are shown in Table 82, the variable surface intervals are shown in Table 83, the aspherical coefficients are shown in Table 84, and the respective aberration diagrams are shown in Fig.44 .

[0721] [Table 81]

[0722] Embodiment 21

[0723]

[0724] [Table 82]

[0725] Embodiment 21

[0726] f 15.39 Bf 12.32 FNo. 1.86 2ωm[°] 110.6

[0727] [Table 83]

[0728] Embodiment 21

[0729] Infinity |β|＝0.1 DD11 5.1532 3.6163 DD22 3.7251 5.2620

[0730] [Table 84]

[0731] Embodiment 21

[0732] Sn 1 2 KA 1.0000000E+00 1.0000000E+00 A4 2.3692064E 05 2.6842614E-05 A6 —3.7276990E-08 —3.1514140E-09 A8 3.3385145E-11 4.9679595E—11 A10 —1.9176905E-14 —8.2860601E-13 A12 2.2045223E-17 7.7875146E-16 A14 6.5384964E-21 1.2570350E-18 A16 —8.3479917E-23 1.0695980E-20 A18 6.8794733E-26 —4.8582124E-23

[0733] Sn 16 17 KA 1.0000000E+00 1.0000000E+00 A4 1.5709615E-05 2.9524649E-05 A6 2.9041615E-08 —4.2470915E-08 A8 2.2563879E-10 3.0126048E-10 A10 -7.3303567E-13 —1.9304744E-12

[0734] Sn 23 24 KA 3.2439831E+03 3.2005465E+01 A4 —7.6750128E-05 —6.2770834E-05 A6 9.6326718E-08 4.3545678E-08 A8 —5.8126441E-10 9.4772143E-10 A10 4.7776236E-12 —1.1179141E-11 A12 —3.0861179E—13 —6.2333720E-14 A14 3.7881779E-15 1.3970699E-15 A16 —1.8755066E—17 —7.1743885E-18 A18 3.2089431E-20 1.2202221E-20

[0735] The corresponding values of conditional expressions (1) to (43) of the imaging lenses of Embodiments 1 to 21 are shown in Tables 85 to 94. In the column of the corresponding values of conditional expressions (40) to (43), the reference symbols of the corresponding lenses are entered in parentheses below each corresponding value. The corresponding values of the embodiments shown in Tables 85 to 94 can be used as the upper or lower limits of the conditional expressions to set the preferred ranges of the conditional expressions.

[0736] [Table 85]

[0737]

[0738]

[0739] [Table 86]

[0740]

[0741] [Table 87]

[0742]

[0743] [Table 88]

[0744]

[0745] [Table 89]

[0746]

[0747] [Table 90]

[0748]

[0749] [Table 91]

[0750]

[0751] [Table 92]

[0752]

[0753] [Table 93]

[0754]

[0755] [Table 94]

[0756]

[0757] The full viewing angle of the imaging lenses of Examples 1 to 21 is greater than 100 degrees, having a wide viewing angle. The open F value of the imaging lenses of Examples 1 to 21 in a state of focusing on an infinite object is less than 2, realizing an optical system with a small F value. The imaging lenses of Examples 1 to 21 are configured to be small, and various aberrations are well corrected and high optical performance is maintained in both a state of focusing on an infinite object and a state of focusing on the nearest object.

[0758] Next, a description will be given of the imaging device according to an embodiment of the present invention. In Figure 45 and Figure 46 FIGS. show an external view of a camera 30 as an imaging device according to an embodiment of the present invention. Figure 45 FIG. shows a perspective view of the camera 30 observed from the front side, Figure 46Fig. 0 shows a perspective view of the camera 30 as viewed from the back side. The camera 30 is a so-called mirrorless digital camera that can detachably mount an interchangeable lens 20. The interchangeable lens 20 is configured to include an imaging lens 1 according to an embodiment of the present invention accommodated in a lens barrel.

[0759] The camera 30 includes a camera body 31, on the upper surface of which a shutter button 32 and a power button 33 are provided. Further, on the back surface of the camera body 31, an operation unit 34, an operation unit 35, and a display unit 36 are provided. The display unit 36 can display the captured image and the image existing within the perspective before shooting.

[0760] A photographing opening for incident light from a subject is provided at the center of the front surface of the camera body 31, and a bayonet 37 is provided at a position corresponding to the photographing opening. The interchangeable lens 20 is mounted on the camera body 31 via the bayonet 37.

[0761] An imaging element such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor) that outputs an imaging signal corresponding to the subject image formed by the interchangeable lens 20, a signal processing circuit that processes the imaging signal output from the imaging element to generate an image, and a recording medium for recording the generated image are provided within the camera body 31. 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 capture is recorded in the above recording medium.

[0762] As described above, the technology of the present invention has been described with reference to embodiments and examples, but the technology of the present invention is not limited to the above embodiments and examples, and various modifications can be made. For example, the radius of curvature, surface interval, refractive index, Abbe number, aspherical coefficient, etc. of each lens are not limited to the values shown in the above examples, and other values can be adopted.

[0763] Furthermore, regarding the imaging device according to the embodiment of the present invention, it is not limited to the above examples. For example, it can also be various types such as a camera other than the mirrorless type, a film camera, and a video camera.

[0764] Regarding the above embodiments and examples, the following appended items are further disclosed.

[0765] [Appended Item 1]

[0766] An imaging lens that sequentially includes a front group, an aperture, and a rear group from the object side to the image side

[0767] The front group successively includes, from the object side to the image side, a first lens which is a negative lens with a concave surface facing the image side and a second lens which is a negative lens with a concave surface facing the image side,

[0768] Two or less focusing lens groups are arranged on the image side of the second lens,

[0769] During focusing, the two or less focusing lens groups move along the optical axis, and lenses other than the two or less focusing lens groups are fixed with respect to the image plane,

[0770] When the back focal length in the air equivalent distance of the entire system in the state of focusing on an infinitely distant object is set as Bf,

[0771] When the focal length of the entire system in the state of focusing on an infinitely distant object is set as f,

[0772] When the maximum half field angle in the state of focusing on an infinitely distant object is set as ωm,

[0773] The imaging lens satisfies the conditional expression (1) shown below:

[0774] 0.3 < Bf / (f × tan ωm) < 1.5 (1).

[0775] [Supplementary Note Item 2]

[0776] The imaging lens according to Supplementary Note Item 1, wherein

[0777] When the distance on the optical axis from the lens surface closest to the object side of the imaging lens to the aperture in the state of focusing on an infinitely distant object is set as STI,

[0778] When the sum of the distance on the optical axis from the lens surface closest to the object side of the imaging lens to the lens surface closest to the image side of the imaging lens and the back focal length in the air equivalent distance of the entire system is set as TL,

[0779] The imaging lens satisfies the conditional expression (2) shown below:

[0780] 0.3 < STI / TL < 0.75 (2).

[0781] [Supplementary Note Item 3]

[0782] The imaging lens according to Supplementary Note Item 1 or 2, wherein

[0783] When the focal length of the front group in the state of focusing on an infinitely distant object is set as fF and the focal length of the rear group in the state of focusing on an infinitely distant object is set as fR,

[0784] The imaging lens satisfies the conditional expression (3) represented as follows:

[0785] -2 < fR / fF < 4 (3).

[0786] [Supplementary Note Item 4]

[0787] The imaging lens according to any one of Supplementary Note Items 1 to 3, wherein

[0788] when the paraxial curvature radius of the object side surface of the first lens is set to RL1f,

[0789] the imaging lens satisfies the conditional expression (4) represented as follows:

[0790] -0.3 < f / RL1f < 8 (4).

[0791] [Supplementary Note Item 5]

[0792] The imaging lens according to any one of Supplementary Note Items 1 to 4, wherein

[0793] when the paraxial curvature radius of the image side surface of the first lens is set to RL1r,

[0794] the imaging lens satisfies the conditional expression (5) represented as follows:

[0795] 0 < f / RL1r < 4 (5).

[0796] [Supplementary Note Item 6]

[0797] The imaging lens according to any one of Supplementary Note Items 1 to 5, wherein

[0798] when the focal length of the front group in the state of focusing on an infinite object is set to fF,

[0799] the imaging lens satisfies the conditional expression (6) represented as follows:

[0800] -1 < f / fF < 2 (6).

[0801] [Supplementary Note Item 7]

[0802] The imaging lens according to any one of Supplementary Note Items 1 to 6, wherein

[0803] when the maximum photographing magnification of the imaging lens is set to β,

[0804] the imaging lens satisfies the conditional expression (7) represented as follows:

[0805] 0.06 < |β| < 0.5 (7).

[0806] [Supplementary Note Item 8]

[0807] The imaging lens according to any one of appended items 1 to 7, wherein,

[0808] When the distance on the optical axis from the lens surface closest to the object side of the imaging lens to the lens surface closest to the image side of the imaging lens in the state of focusing on an infinitely distant object and the back focal length in terms of air of the entire system are summed to be TL,

[0809] the imaging lens satisfies the conditional expression (8) represented as follows:

[0810] 3 < TL / (f × tanωm) < 7 (8).

[0811] [Appended item 9]

[0812] The imaging lens according to any one of appended items 1 to 8, wherein,

[0813] When the open F-number in the state of focusing on an infinitely distant object is set to FNo,

[0814] the imaging lens satisfies the conditional expression (9) represented as follows:

[0815] 0.55 < FNo / tanωm < 2 (9).

[0816] [Appended item 10]

[0817] The imaging lens according to any one of appended items 1 to 9, wherein,

[0818] When the Abbe number of the first lens based on the d-line is set to νL1,

[0819] the imaging lens satisfies the conditional expression (10) represented as follows:

[0820] 20 < νL1 < 95 (10).

[0821] [Appended item 11]

[0822] The imaging lens according to any one of appended items 1 to 10, wherein,

[0823] the imaging lens includes only one of the focusing lens groups,

[0824] the focusing lens group is arranged in the rear group,

[0825] When the focal length of the focusing lens group is set to ff,

[0826] the imaging lens satisfies the conditional expression (11) represented as follows:

[0827] 0.05 < |f / ff| < 0.9 (11).

[0828] [Supplementary Note Item 12]

[0829] The imaging lens according to any one of Supplementary Note Items 1 to 11, wherein,

[0830] The imaging lens includes only 1 of the focusing lens groups,

[0831] The focusing lens group is arranged in the rear group,

[0832] When the focal length of the focusing lens group is set to ff,

[0833] When the sum of the distance on the optical axis from the lens surface closest to the object side of the imaging lens to the lens surface closest to the image side of the imaging lens in the state of focusing on an infinitely distant object and the back focal length under the air equivalent distance of the entire system is set to TL,

[0834] The imaging lens satisfies the conditional expression (12) represented as follows:

[0835] 0.1 < |TL / ff| < 6 (12).

[0836] [Supplementary Note Item 13]

[0837] The imaging lens according to Supplementary Note Item 11 or 12, wherein,

[0838] When the combined focal length of all lenses closer to the image side than the focusing lens group is set to ff_r,

[0839] The imaging lens satisfies the conditional expression (13) represented as follows:

[0840] 0.05 < f / ff_r < 1.5 (13).

[0841] [Supplementary Note Item 14]

[0842] The imaging lens according to any one of Supplementary Note Items 11 to 13, wherein,

[0843] When the combined focal length of all lenses closer to the object side than the focusing lens group is set to ff_f,

[0844] The imaging lens satisfies the conditional expression (14) represented as follows:

[0845] -3 < f / ff_f < 0 (14).

[0846] [Supplementary Note Item 15]

[0847] The imaging lens according to any one of Supplementary Note Items 1 to 10, wherein,

[0848] The imaging lens only includes one said focusing lens group,

[0849] The said focusing lens group is disposed in the front group.

[0850] [Supplementary Note Item 16]

[0851] The imaging lens according to any one of Supplementary Note Items 1 to 10, wherein,

[0852] The said focusing lens group includes the aperture,

[0853] During focusing, the aperture moves along the optical axis.

[0854] [Supplementary Note Item 17]

[0855] The imaging lens according to Supplementary Note Item 16, wherein,

[0856] The imaging lens only includes one said focusing lens group,

[0857] When the focal length of the said focusing lens group is set to ffs,

[0858] The imaging lens satisfies the conditional expression (15) represented as follows:

[0859] 0.1 < f / ffs < 0.5 (15).

[0860] [Supplementary Note Item 18]

[0861] The imaging lens according to any one of Supplementary Note Items 1 to 10, wherein,

[0862] The imaging lens includes two said focusing lens groups,

[0863] When the focusing lens group on the object side among the two said focusing lens groups is set as the first focusing lens group and the focusing lens group on the image side is set as the second focusing lens group,

[0864] During focusing, the first focusing lens group and the second focusing lens group move with different moving amounts.

[0865] [Supplementary Note Item 19]

[0866] The imaging lens according to Supplementary Note Item 18, wherein,

[0867] The first focusing lens group is disposed in the front group, and the second focusing lens group is disposed in the rear group.

[0868] [Supplementary Note Item 20]

[0869] The imaging lens according to Supplementary Note Item 18 or 19, wherein,

[0870] When the focal length of the first focusing lens group is set to ff1,

[0871] and the focal length of the second focusing lens group is set to ff2,

[0872] the imaging lens satisfies the conditional expression (16) represented below:

[0873] 0.2 < ff1 / ff2 < 5 (16).

[0874] [Supplementary Note Item 21]

[0875] The imaging lens according to any one of Supplementary Note Items 18 to 20, wherein

[0876] when the lateral magnification of the first focusing lens group in the state of focusing on an infinitely distant object is set to βf1,

[0877] and the lateral magnification of the second focusing lens group in the state of focusing on an infinitely distant object is set to βf2,

[0878] the imaging lens satisfies the conditional expression (17) represented below:

[0879] 0 < |βf1 / βf2| < 0.6 (17).

[0880] [Supplementary Note Item 22]

[0881] The imaging lens according to any one of Supplementary Note Items 18 to 21, wherein

[0882] when the lateral magnification of the first focusing lens group in the state of focusing on an infinitely distant object is set to βf1,

[0883] the imaging lens satisfies the conditional expression (18) represented below:

[0884] 0 < {βf1 + (1 / βf1)} - 2 < 0.25 (18).

[0885] [Supplementary Note Item 23]

[0886] The imaging lens according to any one of Supplementary Note Items 18 to 22, wherein

[0887] when the lateral magnification of the second focusing lens group in the state of focusing on an infinitely distant object is set to βf2,

[0888] the imaging lens satisfies the conditional expression (19) represented below:

[0889] 0 < {βf2 + (1 / βf2)} - 2 < 0.25 (19).

[0890] [Supplementary Note Item 24]

[0891] The imaging lens according to any one of Supplementary Note Items 18 to 23, wherein,

[0892] When the combined focal length of all lenses on the image side relative to the second focusing lens group is set to f2r,

[0893] The imaging lens satisfies the conditional expression (20) represented as follows:

[0894] 0.1 < f / f2r < 2 (20).

[0895] [Supplementary Note Item 25]

[0896] The imaging lens according to any one of Supplementary Note Items 18 to 24, wherein,

[0897] When the combined focal length of all lenses on the object side relative to the first focusing lens group is set to f1f,

[0898] The imaging lens satisfies the conditional expression (21) represented as follows:

[0899] -3 < f / f1f < 2 (21).

[0900] [Supplementary Note Item 26]

[0901] The imaging lens according to any one of Supplementary Note Items 1 to 25, wherein,

[0902] When the focal length of the first lens is set to fL1,

[0903] When the focal length of the second lens is set to fL2,

[0904] The imaging lens satisfies the conditional expression (22) represented as follows:

[0905] 0 < fL1 / fL2 < 5.5 (22).

[0906] [Supplementary Note Item 27]

[0907] The imaging lens according to any one of Supplementary Note Items 1 to 26, wherein,

[0908] When the focal length of the first lens is set to fL1,

[0909] The imaging lens satisfies the conditional expression (23) represented as follows:

[0910] -8 < fL1 / f < -0.5 (23).

[0911] [Supplementary Note Item 28]

[0912] The imaging lens according to any one of Supplementary Note Items 1 to 27, wherein

[0913] When the paraxial curvature radius of the object-side surface of the first lens is set as RL1f,

[0914] and the paraxial curvature radius of the image-side surface of the first lens is set as RL1r,

[0915] the imaging lens satisfies the conditional expression (24) represented as follows:

[0916] -2.5 < (RL1r - RL1f) / (RL1r + RL1f) < -0.1 (24).

[0917] [Supplementary Note Item 29]

[0918] The imaging lens according to any one of Supplementary Note Items 1 to 28, wherein

[0919] When the paraxial curvature radius of the object-side surface of the second lens is set as RL2f,

[0920] and the paraxial curvature radius of the image-side surface of the second lens is set as RL2r,

[0921] the imaging lens satisfies the conditional expression (25) represented as follows:

[0922] -1.5 < (RL2r - RL2f) / (RL2r + RL2f) < -0.05 (25).

[0923] [Supplementary Note Item 30]

[0924] The imaging lens according to any one of Supplementary Note Items 1 to 29, wherein

[0925] A third lens as a negative lens is disposed adjacent to the image side of the second lens,

[0926] and a fourth lens as a positive lens is disposed adjacent to the image side of the third lens,

[0927] When the focal length of the third lens is set as fL3,

[0928] and the focal length of the fourth lens is set as fL4,

[0929] the imaging lens satisfies the conditional expression (26) represented as follows:

[0930] -8 < fL3 / fL4 < 0 (26).

[0931] [Supplementary Item 31]

[0932] The imaging lens according to any one of Supplementary Items 1 to 30, wherein

[0933] when the paraxial curvature radius of the object-side surface of the lens closest to the image side of the imaging lens is set as R Lef,

[0934] and the paraxial curvature radius of the image-side surface of the lens closest to the image side of the imaging lens is set as R ler,

[0935] the imaging lens satisfies the conditional expression (27) represented as follows:

[0936] 0.4 < (R ler - R Lef) / (R ler + R Lef) < 5.5 (27).

[0937] [Supplementary Item 32]

[0938] The imaging lens according to any one of Supplementary Items 1 to 31, wherein

[0939] at least one of the object-side surface and the image-side surface of the first lens is an aspherical surface,

[0940] when the paraxial curvature radius of the object-side surface of the first lens is set as R L1f,

[0941] the paraxial curvature radius of the image-side surface of the first lens is set as R L1r,

[0942] the curvature radius at the position of the maximum effective diameter of the object-side surface of the first lens is set as R yL1f,

[0943] and the curvature radius at the position of the maximum effective diameter of the image-side surface of the first lens is set as R yL1r,

[0944] the imaging lens satisfies the conditional expression (28) represented as follows:

[0945] 0.5 < (1 / R L1f - 1 / R L1r) / (1 / R yL1f - 1 / R yL1r) < 7 (28).

[0946] [Supplementary Item 33]

[0947] The imaging lens according to any one of Supplementary Items 1 to 32, wherein

[0948] the front group includes at least one positive lens,

[0949] When the focal length of the positive lens with the strongest optical power among the positive lenses included in the front group is set to fFp,

[0950] the imaging lens satisfies the conditional expression (29) represented as follows:

[0951] 0.1 < f / fFp < 3 (29).

[0952] [Supplementary Note 34]

[0953] The imaging lens according to any one of Supplementary Notes 1 to 33, wherein

[0954] the rear group includes at least one positive lens,

[0955] When the focal length of the positive lens with the strongest optical power among the positive lenses included in the rear group is set to fRp,

[0956] and the focal length of the rear group in the state of focusing on an infinitely distant object is set to fR,

[0957] the imaging lens satisfies the conditional expression (30) represented as follows:

[0958] 0.3 < fR / fRp < 5 (30).

[0959] [Supplementary Note 35]

[0960] The imaging lens according to any one of Supplementary Notes 1 to 34, wherein

[0961] the rear group includes a cemented lens formed by sequentially cementing a positive lens with its convex surface facing the object side and a negative lens from the object side,

[0962] When the Abbe number of the positive lens of the cemented lens based on the d-line is set to νRp,

[0963] and the Abbe number of the negative lens of the cemented lens based on the d-line is set to νRn,

[0964] the imaging lens satisfies the conditional expression (31) represented as follows:

[0965] 10 < νRp - νRn < 75 (31).

[0966] [Supplementary Note 36]

[0967] The imaging lens according to Supplementary Note 35, wherein

[0968] When the refractive index of the positive lens of the cemented lens with respect to the d-line is set to NRp,

[0969] When the refractive index of the negative lens of the cemented lens with respect to the d-line is set to NRn, the imaging lens satisfies the conditional expression (32) represented as follows:

[0970] 0.2 < NRp - NRn < 0.9 (32).

[0971] [Supplementary Note Item 37]

[0972] The imaging lens according to any one of Supplementary Note Items 1 to 36, wherein

[0973] an LFe lens as a positive lens is disposed on the image side most adjacent to the front group.

[0974] [Supplementary Note Item 38]

[0975] The imaging lens according to Supplementary Note Item 37, wherein

[0976] the LFe lens is a biconvex lens.

[0977] [Supplementary Note Item 39]

[0978] The imaging lens according to Supplementary Note Item 37 or 38, wherein

[0979] at least one of the object-side surface and the image-side surface of the LFe lens is an aspherical surface,

[0980] when the paraxial curvature radius of the object-side surface of the LFe lens is set to RcLFef,

[0981] when the paraxial curvature radius of the image-side surface of the LFe lens is set to RcLFer,

[0982] when the curvature radius at the position of the maximum effective diameter of the object-side surface of the LFe lens is set to RyLFef,

[0983] when the curvature radius at the position of the maximum effective diameter of the image-side surface of the LFe lens is set to RyLFer,

[0984] the imaging lens satisfies the conditional expression (33) represented as follows:

[0985] 0.5 < (1 / RcLFef - 1 / RcLFer) / (1 / RyLFef - 1 / RyLFer) < 7 (33).

[0986] [Supplementary Note Item 40]

[0987] The imaging lens according to any one of Supplementary Note Items 37 to 39, wherein

[0988] When the paraxial curvature radius of the object-side surface of the LFe lens is set as RcLFef and the paraxial curvature radius of the image-side surface of the LFe lens is set as RcLFer,

[0989] the imaging lens satisfies the conditional expression (34) represented as follows:

[0990] -4 < (RcLFef - RcLFer) / (RcLFef + RcLFer) < 10 (34).

[0991] [Supplementary Note Item 41]

[0992] According to the imaging lens described in any one of Supplementary Note Items 37 to 40, wherein,

[0993] when the Abbe number of the LFe lens based on the d line is set as νLFe,

[0994] the imaging lens satisfies the conditional expression (35) represented as follows:

[0995] 15 < νLFe < 90 (35).

[0996] [Supplementary Note Item 42]

[0997] According to the imaging lens described in any one of Supplementary Note Items 1 to 41, wherein,

[0998] when the central thickness of the first lens is set as D1,

[0999] when the sum of the distance on the optical axis from the lens surface closest to the object of the imaging lens to the lens surface closest to the image of the imaging lens in the state of focusing on an infinitely distant object and the back focal length under the air-converted distance of the entire system is set as TL,

[1000] the imaging lens satisfies the conditional expression (36) represented as follows:

[1001] 0.007 < D1 / TL < 0.1 (36).

[1002] [Supplementary Note Item 43]

[1003] According to the imaging lens described in any one of Supplementary Note Items 1 to 42, wherein,

[1004] when the thickness of the first lens in the optical axis direction at the height of the maximum effective diameter of the image-side surface of the first lens is set as DH1,

[1005] when the central thickness of the first lens is set as D1,

[1006] the imaging lens satisfies the conditional expression (37) represented as follows:

[1007] 2 < DH1 / D1 < 10 (37).

[1008] [Supplementary Note Item 44]

[1009] The imaging lens according to any one of Supplementary Note Items 1 to 43, wherein,

[1010] When the Abbe number based on the d-line of the lens closest to the image side of the imaging lens is set as νLe,

[1011] The imaging lens satisfies the conditional expression (38) represented as follows:

[1012] 30 < νLe < 95 (38).

[1013] [Supplementary Note Item 45]

[1014] The imaging lens according to any one of Supplementary Note Items 1 to 44, wherein,

[1015] When the effective radius of the object-side surface of the first lens is set as EL1,

[1016] The imaging lens satisfies the conditional expression (39) represented as follows:

[1017] 0.7 < EL1 / (f × tanωm) < 2 (39).

[1018] [Supplementary Note Item 46]

[1019] The imaging lens according to any one of Supplementary Note Items 1 to 45, which includes an Ls lens on the image side of the second lens,

[1020] When the refractive index of the Ls lens with respect to the d-line is set as NLs,

[1021] the Abbe number based on the d-line of the Ls lens is set as νLs,

[1022] and the partial dispersion ratio between the g-line and the F-line of the Ls lens is set as θgFLs,

[1023] The imaging lens satisfies the conditional expressions (40), (41), (42), and (43) represented as follows:

[1024] 0.005 < NLs - (2.015 - 0.0068 × νLs) < 0.15 (40)

[1025] 49.8 < νLs < 65 (41)

[1026] 0.543 < θgFLs < 0.58 (42)

[1027] -0.011 < θgFLs - (0.6418 - 0.00168 × νLs) < 0.035 (43).

[1028] [Supplementary Note Item 47]

[1029] The imaging lens according to any one of Supplementary Note Items 1 to 46 satisfies the conditional expression (1-1) represented as follows:

[1030] 0.43 < Bf / (f × tanωm) < 1.1 (1-1).

[1031] [Supplementary Note Item 48]

[1032] The imaging lens according to any one of Supplementary Note Items 1 to 47, wherein

[1033] when the sum of the distance on the optical axis from the lens surface closest to the object side of the imaging lens to the lens surface closest to the image side of the imaging lens in the state of focusing on an infinitely distant object and the back focal length under the air-converted distance of the entire system is set as TL,

[1034] the imaging lens satisfies the conditional expression (8-1) represented as follows:

[1035] 3.2 < TL / (f × tanωm) < 6.5 (8-1).

[1036] [Supplementary Note Item 49]

[1037] The imaging lens according to Supplementary Note Item 48 satisfies the conditional expression (8-2) represented as follows:

[1038] 3.4 < TL / (f × tanωm) < 5.9 (8-2).

[1039] [Supplementary Note Item 50]

[1040] The imaging lens according to Supplementary Note Item 48 satisfies the conditional expression (8-3) represented as follows:

[1041] 3.5 < TL / (f × tanωm) < 5.65 (8-3).

[1042] [Supplementary Note Item 51]

[1043] The imaging lens according to any one of Supplementary Note Items 1 to 50, wherein

[1044] when the open F-number in the state of focusing on an infinitely distant object is set as FNo,

[1045] the imaging lens satisfies the conditional expression (9-1) represented as follows:

[1046] 0.64 < FNo / tan ωm < 1.62 (9-1).

[1047] [Supplementary Note Item 52]

[1048] The imaging lens according to Supplementary Note Item 51 satisfies the conditional expression (9-2) represented as follows:

[1049] 0.66 < FNo / tan ωm < 1.55 (9-2).

[1050] [Supplementary Note Item 53]

[1051] The imaging lens according to Supplementary Note Item 51 satisfies the conditional expression (9-3) represented as follows:

[1052] 0.7 < FNo / tan ωm < 1.35 (9-3).

[1053] [Supplementary Note Item 54]

[1054] The imaging lens according to any one of Supplementary Note Items 1 to 53, wherein

[1055] when the Abbe number of the first lens based on the d-line is set as νL1,

[1056] the imaging lens satisfies the conditional expression (10-1) represented as follows:

[1057] 28 < νL1 < 59 (10-1).

[1058] [Supplementary Note Item 55]

[1059] The imaging lens according to Supplementary Note Item 54 satisfies the conditional expression (10-2) represented as follows:

[1060] 32 < νL1 < 48 (10-2).

[1061] [Supplementary Note Item 56]

[1062] An imaging device including the imaging lens according to any one of Supplementary Note Items 1 to 55.

[1063] All documents, patent applications, and technical standards described in this specification are incorporated herein by reference to the same extent as if each individual document, patent application, and technical standard were specifically and separately indicated to be incorporated by reference.

Claims

1. An imaging lens that sequentially includes a front group, an aperture, and a rear group from the object side to the image side, wherein the front group sequentially and continuously includes a first lens as a negative lens with a concave surface facing the image side and a second lens as a negative lens with a concave surface facing the image side from the object-side most part to the image side, two or fewer focusing lens groups are arranged on the image side of the second lens, during focusing, the two or fewer focusing lens groups move along the optical axis, and lenses other than the two or fewer focusing lens groups are fixed relative to the image plane, when the back focal length in the air equivalent distance of the entire system in the state of focusing on an infinitely distant object is set as Bf, when the focal length of the entire system in the state of focusing on an infinitely distant object is set as f, when the maximum half-angle of view in the state of focusing on an infinitely distant object is set as ωm, the imaging lens satisfies the following conditional expression (1): 0.3 < Bf / (f × tan ωm) < 1.5 (1).

2. The imaging lens according to claim 1, wherein when the distance on the optical axis from the lens surface on the object-side most part of the imaging lens to the aperture in the state of focusing on an infinitely distant object is set as STI, when the sum of the distance on the optical axis from the lens surface on the object-side most part of the imaging lens to the lens surface on the image-side most part of the imaging lens and the back focal length in the air equivalent distance of the entire system is set as TL, the imaging lens satisfies the following conditional expression (2): 0.3 < STI / TL < 0.75 (2).

3. The imaging lens according to claim 1, wherein when the focal length of the front group in the state of focusing on an infinitely distant object is set as fF, when the focal length of the rear group in the state of focusing on an infinitely distant object is set as fR, the imaging lens satisfies the following conditional expression (3): -2 < fR / fF < 4 (3).

4. The imaging lens according to claim 1, wherein when the paraxial curvature radius of the object-side surface of the first lens is set as RL1f, the imaging lens satisfies the following conditional expression (4): -0.3 < f / RL1f < 8 (4).

5. The imaging lens according to claim 1, wherein when the paraxial curvature radius of the image-side surface of the first lens is set as RL1r, the imaging lens satisfies the following conditional expression (5): 0 < f / RL1r < 4 (5).

6. The imaging lens according to claim 1, wherein when the focal length of the front group in the state of focusing on an infinitely distant object is set as fF, the imaging lens satisfies the following conditional expression (6): -1 < f / fF < 2 (6).

7. The imaging lens according to claim 1, wherein when the maximum photographic magnification of the imaging lens is set as β, the imaging lens satisfies the following conditional expression (7): 0.06<|β|<0.5 (7)。 8. The imaging lens according to claim 1, wherein When the sum of the distance on the optical axis from the lens surface closest to the object of the imaging lens to the lens surface closest to the image of the imaging lens in the state of focusing on an infinitely distant object and the back focal length under the air equivalent distance of the entire system is set as TL, the imaging lens satisfies the conditional expression (8) represented as follows: 3 < TL / (f × tanωm) < 7 (8).

9. The imaging lens according to claim 1, wherein, when the open F-number in the state of focusing on an infinitely distant object is set as FNo, the imaging lens satisfies the conditional expression (9) represented as follows: 0.55 < FNo / tanωm < 2 (9).

10. The imaging lens according to claim 1, wherein, when the Abbe number of the first lens based on the d-line is set as νL1, the imaging lens satisfies the conditional expression (10) represented as follows: 20 < νL1 < 95 (10).

11. The imaging lens according to claim 1, wherein, when the sum of the distance on the optical axis from the lens surface closest to the object of the imaging lens to the lens surface closest to the image of the imaging lens in the state of focusing on an infinitely distant object and the back focal length under the air equivalent distance of the entire system is set as TL, the imaging lens satisfies the conditional expression (8-3) represented as follows: 3.5 < TL / (f × tanωm) < 5.65 (8-3).

12. The imaging lens according to claim 11, wherein, when the open F-number in the state of focusing on an infinitely distant object is set as FNo, the imaging lens satisfies the conditional expression (9-3) represented as follows: 0.7 < FNo / tanωm < 1.35 (9-3).

13. The imaging lens according to claim 12, wherein, when the Abbe number of the first lens based on the d-line is set as νL1, the imaging lens satisfies the conditional expression (10-1) represented as follows: 28 < νL1 < 59 (10-1).

14. The imaging lens according to claim 1, wherein, the imaging lens includes only one of the focusing lens groups, the focusing lens group is arranged in the rear group, when the focal length of the focusing lens group is set as ff, the imaging lens satisfies the conditional expression (11) represented as follows: 0.05 < |f / ff| < 0.9 (11).

15. The imaging lens according to claim 1, wherein, the imaging lens includes only one of the focusing lens groups, the focusing lens group is arranged in the rear group, when the focal length of the focusing lens group is set as ff, when the sum of the distance on the optical axis from the lens surface closest to the object of the imaging lens to the lens surface closest to the image of the imaging lens in the state of focusing on an infinitely distant object and the back focal length under the air equivalent distance of the entire system is set as TL, the imaging lens satisfies the conditional expression (12) represented as follows: 0.1 < |TL / ff| < 6 (12).

16. The imaging lens according to claim 14, wherein, When the combined focal length of all the lenses on the image side relative to the focusing lens group is set as ff_r, the imaging lens satisfies the conditional expression (13) represented as follows: 0.05 < f / ff_r < 1.5 (13).

17. The imaging lens according to claim 14, wherein when the combined focal length of all the lenses on the object side relative to the focusing lens group is set as ff_f, the imaging lens satisfies the conditional expression (14) represented as follows: -3 < f / ff_f < 0 (14).

18. The imaging lens according to claim 14, wherein when the sum of the distance on the optical axis from the lens surface closest to the object side of the imaging lens to the lens surface closest to the image side of the imaging lens in the state of focusing on an infinitely distant object and the back focal length under the air equivalent distance of the entire system is set as TL, the imaging lens satisfies the conditional expression (8-1) represented as follows: 3.2 < TL / (f×tanωm) < 6.5 (8-1).

19. The imaging lens according to claim 18, wherein when the open F value in the state of focusing on an infinitely distant object is set as FNo, the imaging lens satisfies the conditional expression (9-3) represented as follows: 0.7 < FNo / tanωm < 1.35 (9-3).

20. The imaging lens according to claim 19, wherein when the Abbe number of the d-line reference of the first lens is set as vL1, the imaging lens satisfies the conditional expression (10-1) represented as follows: 28 < νL1 < 59 (10-1).

21. The imaging lens according to claim 1, wherein the imaging lens includes only one said focusing lens group, and the focusing lens group is arranged in the front group.

22. The imaging lens according to claim 21, wherein when the sum of the distance on the optical axis from the lens surface closest to the object side of the imaging lens to the lens surface closest to the image side of the imaging lens in the state of focusing on an infinitely distant object and the back focal length under the air equivalent distance of the entire system is set as TL, the imaging lens satisfies the conditional expression (8-2) represented as follows: 3.4 < TL / (f×tanωm) < 5.9 (8-2).

23. The imaging lens according to claim 22, wherein when the open F value in the state of focusing on an infinitely distant object is set as FNo, the imaging lens satisfies the conditional expression (9-2) represented as follows: 0.66 < FNo / tanωm < 1.55 (9-2).

24. The imaging lens according to claim 1, wherein the focusing lens group includes the aperture, and during focusing, the aperture moves along the optical axis.

25. The imaging lens according to claim 24, wherein the imaging lens includes only one said focusing lens group, when the focal length of the focusing lens group is set as ffs, the imaging lens satisfies the conditional expression (15) represented as follows: 0.1 < f / ffs < 0.5 (15).

26. The imaging lens according to claim 24, wherein when the sum of the distance on the optical axis from the lens surface closest to the object side of the imaging lens to the lens surface closest to the image side of the imaging lens in the state of focusing on an infinitely distant object and the back focal length in terms of air of the entire system is defined as TL, the imaging lens satisfies the conditional expression (8-2) represented as follows: 3.4 < TL / (f × tanωm) < 5.9 (8-2).

27. The imaging lens according to claim 26, wherein when the open F-number in the state of focusing on an infinitely distant object is defined as FNo, the imaging lens satisfies the conditional expression (9) represented as follows: 0.55 < FNo / tanωm < 2 (9).

28. The imaging lens according to claim 24, wherein when the sum of the distance on the optical axis from the lens surface closest to the object side of the imaging lens to the lens surface closest to the image side of the imaging lens in the state of focusing on an infinitely distant object and the back focal length in terms of air of the entire system is defined as TL, the imaging lens satisfies the conditional expression (8) represented as follows: 3 < TL / (f × tanωm) < 7 (8).

29. The imaging lens according to claim 28, wherein when the open F-number in the state of focusing on an infinitely distant object is defined as FNo, the imaging lens satisfies the conditional expression (9-1) represented as follows: 0.64 < FNo / tanωm < 1.62 (9-1).

30. The imaging lens according to claim 1, wherein the imaging lens includes two of the focusing lens groups, when the focusing lens group on the object side among the two focusing lens groups is defined as the first focusing lens group and the focusing lens group on the image side is defined as the second focusing lens group, during focusing, the first focusing lens group and the second focusing lens group move with different amounts of movement.

31. The imaging lens according to claim 30, wherein when the sum of the distance on the optical axis from the lens surface closest to the object side of the imaging lens to the lens surface closest to the image side of the imaging lens in the state of focusing on an infinitely distant object and the back focal length in terms of air of the entire system is defined as TL, the imaging lens satisfies the conditional expression (8-2) represented as follows: 3.4 < TL / (f × tanωm) < 5.9 (8-2).

32. The imaging lens according to claim 31, wherein when the open F-number in the state of focusing on an infinitely distant object is defined as FNo, the imaging lens satisfies the conditional expression (9-2) represented as follows: 0.66 < FNo / tanωm < 1.55 (9-2).

33. The imaging lens according to claim 30, wherein the first focusing lens group is disposed in the front group and the second focusing lens group is disposed in the rear group.

34. The imaging lens according to claim 33, wherein When the sum of the distance on the optical axis from the lens surface closest to the object of the imaging lens to the lens surface closest to the image of the imaging lens in the state of focusing on an infinitely distant object and the back focal length in terms of air of the entire system is defined as TL, the imaging lens satisfies the conditional expression (8) represented as follows: 3 < TL / (f × tanωm) < 7 (8).

35. The imaging lens according to claim 34, wherein when the open F-number in the state of focusing on an infinitely distant object is defined as FNo, the imaging lens satisfies the conditional expression (9-2) represented as follows: 0.66 < FNo / tanωm < 1.55 (9-2).

36. The imaging lens according to claim 35, which satisfies the conditional expression (1-1) represented as follows: 0.43 < Bf / (f × tanωm) < 1.1 (1-1).

37. The imaging lens according to claim 36, wherein when the Abbe number of the first lens based on the d-line is defined as νL1, the imaging lens satisfies the conditional expression (10) represented as follows: 20 < νL1 < 95 (10).

38. The imaging lens according to claim 30, wherein when the focal length of the first focusing lens group is defined as ff1, and the focal length of the second focusing lens group is defined as ff2, the imaging lens satisfies the conditional expression (16) represented as follows: 0.2 < |ff1 / ff2| < 5 (16).

39. The imaging lens according to claim 30, wherein when the lateral magnification of the first focusing lens group in the state of focusing on an infinitely distant object is defined as βf1, and the lateral magnification of the second focusing lens group in the state of focusing on an infinitely distant object is defined as βf2, the imaging lens satisfies the conditional expression (17) represented as follows: 0 < |βf1 / βf2| < 0.6 (17).

40. The imaging lens according to claim 30, wherein when the lateral magnification of the first focusing lens group in the state of focusing on an infinitely distant object is defined as βf1, the imaging lens satisfies the conditional expression (18) represented as follows: 0 < {βf1+(1 / βf1)} -2 <0.25 (18).

41. The imaging lens according to claim 30, wherein when the lateral magnification of the second focusing lens group in the state of focusing on an infinitely distant object is defined as βf2, the imaging lens satisfies the conditional expression (19) represented as follows: 0 < {βf2+(1 / βf2)} -2 <0.25 (19).

42. The imaging lens according to claim 30, wherein when the combined focal length of all the lenses on the image side with respect to the second focusing lens group is defined as f2r, the imaging lens satisfies the conditional expression (20) represented as follows: 0.1 < f / f2r < 2 (20).

43. The imaging lens according to claim 30, wherein when the combined focal length of all the lenses on the object side with respect to the first focusing lens group is defined as f1f, the imaging lens satisfies the conditional expression (21) represented as follows: -3 < f / f1f < 2 (21).

44. The imaging lens according to claim 1, wherein when the focal length of the first lens is set as fL1, and the focal length of the second lens is set as fL2, the imaging lens satisfies the conditional expression (22) represented as follows: 0 < fL1 / fL2 < 5.5 (22).

45. The imaging lens according to claim 1, wherein when the focal length of the first lens is set as fL1, the imaging lens satisfies the conditional expression (23) represented as follows: -8 < fL1 / f < -0.5 (23).

46. The imaging lens according to claim 1, wherein when the paraxial curvature radius of the object-side surface of the first lens is set as RL1f, and the paraxial curvature radius of the image-side surface of the first lens is set as RL1r, the imaging lens satisfies the conditional expression (24) represented as follows: -2.5 < (RL1r - RL1f) / (RL1r + RL1f) < -0.1 (24).

47. The imaging lens according to claim 1, wherein when the paraxial curvature radius of the object-side surface of the second lens is set as RL2f, and the paraxial curvature radius of the image-side surface of the second lens is set as RL2r, the imaging lens satisfies the conditional expression (25) represented as follows: -1.5 < (RL2r - RL2f) / (RL2r + RL2f) < -0.05 (25).

48. The imaging lens according to claim 1, wherein a third lens as a negative lens is disposed adjacent to the image side of the second lens, a fourth lens as a positive lens is disposed adjacent to the image side of the third lens, when the focal length of the third lens is set as fL3, and the focal length of the fourth lens is set as fL4, the imaging lens satisfies the conditional expression (26) represented as follows: -8 < fL3 / fL4 < 0 (26).

49. The imaging lens according to claim 1, wherein when the paraxial curvature radius of the object-side surface of the lens closest to the image side of the imaging lens is set as RLef, and the paraxial curvature radius of the image-side surface of the lens closest to the image side of the imaging lens is set as Rler, the imaging lens satisfies the conditional expression (27) represented as follows: 0.4 < (Rler - RLef) / (Rler + RLef) < 5.5 (27).

50. The imaging lens according to claim 1, wherein at least one of the object-side surface and the image-side surface of the first lens is an aspherical surface, when the paraxial curvature radius of the object-side surface of the first lens is set as RL1f, the paraxial curvature radius of the image-side surface of the first lens is set as RL1r, the curvature radius at the position of the maximum effective diameter of the object-side surface of the first lens is set as RyL1f, and the curvature radius at the position of the maximum effective diameter of the image-side surface of the first lens is set as RyL1r, the imaging lens satisfies the conditional expression (28) represented as follows: 0.5 < (1 / RL1f - 1 / RL1r) / (1 / RyL1f - 1 / RyL1r) < 7 (28).

51. The imaging lens according to claim 50, wherein when the Abbe number of the first lens with respect to the d-line is set as νL1, the imaging lens satisfies the conditional expression (10-2) represented as follows: 32 < νL1 < 48 (10-2).

52. The imaging lens according to claim 1, wherein the front group includes at least one positive lens, when the focal length of the positive lens having the strongest optical power among the positive lenses included in the front group is set as fFp, the imaging lens satisfies the conditional expression (29) represented as follows: 0.1 < f / fFp < 3 (29).

53. The imaging lens according to claim 1, wherein the rear group includes at least one positive lens, when the focal length of the positive lens having the strongest optical power among the positive lenses included in the rear group is set as fRp, and when the focal length of the rear group in a state of focusing on an infinitely distant object is set as fR, the imaging lens satisfies the conditional expression (30) represented as follows: 0.3 < fR / fRp < 5 (30).

54. The imaging lens according to claim 1, wherein the rear group includes a cemented lens formed by sequentially cementing a positive lens with its convex surface facing the object side and a negative lens from the object side, when the Abbe number of the positive lens of the cemented lens with respect to the d-line is set as νRp, and when the Abbe number of the negative lens of the cemented lens with respect to the d-line is set as vRn, the imaging lens satisfies the conditional expression (31) represented as follows: 10 < νRp - νRn < 75 (31).

55. The imaging lens according to claim 54, wherein when the refractive index of the positive lens of the cemented lens with respect to the d-line is set as NRp, and when the refractive index of the negative lens of the cemented lens with respect to the d-line is set as NRn, the imaging lens satisfies the conditional expression (32) represented as follows: 0.2 < NRp - NRn < 0.9 (32).

56. The imaging lens according to claim 1, wherein an LFe lens as a positive lens is disposed on the most image side of the front group.

57. The imaging lens according to claim 56, wherein the LFe lens is a biconvex lens.

58. The imaging lens according to claim 56, wherein at least one of the object-side surface and the image-side surface of the LFe lens is an aspherical surface, when the paraxial curvature radius of the object-side surface of the LFe lens is set as RcLFef, the paraxial curvature radius of the image-side surface of the LFe lens is set as RcLFer, the curvature radius at the position of the maximum effective diameter of the object-side surface of the LFe lens is set as RyLFef, and the curvature radius at the position of the maximum effective diameter of the image-side surface of the LFe lens is set as RyLFer, the imaging lens satisfies the conditional expression (33) represented as follows: 0.5 < (1 / RcLFef - 1 / RcLFer) / (1 / RyLFef - 1 / RyLFer) < 7 (33).

59. The imaging lens according to claim 56, wherein when the paraxial curvature radius of the object-side surface of the LFe lens is RcLFef and the paraxial curvature radius of the image-side surface of the LFe lens is RcLFer, the imaging lens satisfies the conditional expression (34) represented below: -4 < (RcLFef - RcLFer) / (RcLFef + RcLFer) < 10 (34).

60. The imaging lens according to claim 56, wherein when the Abbe number of the LFe lens based on the d line is νLFe, the imaging lens satisfies the conditional expression (35) represented below: 15 < νLFe < 90 (35).

61. The imaging lens according to claim 1, wherein when the center thickness of the first lens is D1 and the sum of the distance on the optical axis from the lens surface closest to the object of the imaging lens to the lens surface closest to the image of the imaging lens in the state of focusing on an infinitely distant object and the back focal length under the air-converted distance of the entire system is TL, the imaging lens satisfies the conditional expression (36) represented below: 0.007 < D1 / TL < 0.1 (36).

62. The imaging lens according to claim 1, wherein when the thickness of the first lens in the optical axis direction at the height of the maximum effective diameter of the image-side surface of the first lens is DH1 and the center thickness of the first lens is D1, the imaging lens satisfies the conditional expression (37) represented below: 2 < DH1 / D1 < 10 (37).

63. The imaging lens according to claim 1, wherein when the Abbe number of the lens closest to the image of the imaging lens based on the d line is νLe, the imaging lens satisfies the conditional expression (38) represented below: 30 < νLe < 95 (38).

64. The imaging lens according to claim 1, wherein when the effective radius of the object-side surface of the first lens is EL1, the imaging lens satisfies the conditional expression (39) represented below: 0.7 < EL1 / (f × tanωm) < 2 (39).

65. The imaging lens according to claim 1, which includes an Ls lens on the image side of the second lens. When the refractive index of the Ls lens with respect to the d line is NLs, the Abbe number of the Ls lens based on the d line is νLs, and the partial dispersion ratio between the g line and the F line of the Ls lens is θgFLs, the imaging lens satisfies the conditional expressions (40), (41), (42), and (43) represented below: 0.005 < NLs - (2.015 - 0.0068 × νLs) < 0.15 (40) 49.8 < vLs < 65 (41) 0.543 < θgFLs < 0.58 (42) -0.011 < θgFLs - (0.6418 - 0.00168 × ν Ls) < 0.035 (43).

66. The imaging lens according to claim 65, wherein when the distance on the optical axis from the lens surface closest to the object side of the imaging lens to the lens surface closest to the image side of the imaging lens in a state of focusing on an infinitely distant object and the back focal length in terms of air of the entire system are set as TL, the imaging lens satisfies the conditional expression (8-3) represented as follows: 3.5 < TL / (f × tanωm) < 5.65 (8-3).

67. The imaging lens according to claim 66, wherein when the open F-number in a state of focusing on an infinitely distant object is set as FNo, the imaging lens satisfies the conditional expression (9) represented as follows: 0.55 < FNo / tanωm < 2 (9).

68. An imaging device including the imaging lens according to any one of claims 1 to 67.

Images