Imaging lens and imaging device

Abstract

The invention provides an imaging lens and an imaging device with the imaging lens, wherein the total length of a lens system is shortened, and the imaging lens has good optical performance. The imaging lens includes, in order from an object side to an image side, a first lens group, a second lens group, and a third lens group having positive refractive power. During focusing, the second lens group moves. The lens closest to the object side is a negative meniscus lens, and at least one of the second lens from the object side and the third lens from the object side is a lens other than the negative meniscus lens. The diaphragm is disposed closer to the image side than the second lens from the object side. The imaging lens satisfies a preset conditional expression.

Description

Technical Field

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

[0002] Conventionally, as imaging lenses used for digital cameras and the like, lens systems described in Patent Document 1 and Patent Document 2 below are known.

[0003] Patent Document 1: Japanese Patent Application Laid-Open No. 2023-045839

[0004] Patent Document 2: Japanese Patent Application Laid-Open No. 2023-019073

[0005] There is a demand for an imaging lens that shortens the overall length of the lens system and has good optical performance. These requirements are increasing year by year. Summary of the Invention

[0006] An object of the present invention is to provide an imaging lens having a shortened total length of a lens system and excellent optical performance, and an imaging device including the imaging lens.

[0007] An imaging lens according to one embodiment of the present invention includes, in order from the object side to the image side, a first lens group, a second lens group, and a third lens group having positive refractive power. During focusing, the first lens group and the third lens group are fixed relative to the image plane, the second lens group moves along the optical axis, the lens closest to the object side is a negative meniscus lens, at least one of the second lens from the object side and the third lens from the object side is a lens other than a negative meniscus lens, and a stop is arranged closer to the image side than the second lens from the object side. The imaging lens satisfies the following conditional expressions (1) and (2):

[0008] 1<TL / Y<4.5 (1)

[0009] -0.18<(Yf×tanωm) / (f×tanωm)<-0.02 (2).

[0010] Here, the sum of the distance on the optical axis from the lens surface closest to the object side of the first lens group to the lens surface closest to the image side of the third lens group and the back focal length of the entire system calculated in terms of air conversion distance is set to TL, the maximum image height is set to Y, the focal length of the entire system when focused on an object at infinity is set to f, and the maximum half angle of view when focused on an object at infinity is set to ωm.

[0011] Preferably, in a cross section including the optical axis, when the radius of the circle passing through three points consisting of the point on the optical axis of the lens surface and the two outermost points of the effective diameter is defined as Rc of the lens surface, and the sign of Rc is set to positive when the point on the optical axis is closer to the object side than the center of the circle, and set to negative when the point on the optical axis is closer to the image side than the center of the circle, the number of lenses with an aspherical shape for the object-side lens surface included in the third lens group and with the sign of Rc of the object-side lens surface being negative is one or two.

[0012] The number of lenses included in the imaging lens is preferably five or more and ten or less.

[0013] When the unit of ωm is degrees, the imaging lens of the above method preferably satisfies the following conditional expression (3):

[0014] 47 < ωm < 60 (3).

[0015] When the focal length of the first lens group is set to fG1, the imaging lens of the above method preferably satisfies the following conditional expression (4):

[0016] 0.01 < f / fG1 < 1.6 (4).

[0017] When the distance on the optical axis from the lens surface closest to the object of the first lens group to the diaphragm in the state of focusing on an infinite object is set to dL1St, the imaging lens of the above method preferably satisfies the following conditional expression (5):

[0018] 0.1 < dL1St / Y < 2.1 (5).

[0019] When the angle formed by the principal ray of the maximum image height incident on the image plane and the axis parallel to the optical axis in the state of focusing on an infinite object is set to CRA, and the unit of CRA is degrees, the imaging lens of the above method preferably satisfies the following conditional expression (6):

[0020] 16 < |CRA| < 69 (6).

[0021] When the back focal length of the entire system in terms of air-equivalent distance is set to Bf, the imaging lens of the above method preferably satisfies the following conditional expression (7):

[0022] 0.06 < Bf / TL < 0.3 (7).

[0023] When the unit of f is millimeters and the open F value in the state of focusing on an infinite object is set to Fno, the imaging lens of the above method preferably satisfies the following conditional expression (8):

[0024] 1.7 < f / Fno < 4.1 (8).

[0025] When the focal length of the second lens group is set to fG2, the imaging lens of the above-described method preferably satisfies the conditional expression (9) shown below:

[0026] 0.24 < |f / fG2| < 2.4 (9).

[0027] Preferably, one or two single lenses with negative refractive power and one or two single lenses with positive refractive power are arranged on the object side of the diaphragm, and the number of lenses arranged on the object side of the diaphragm is four or less.

[0028] When a positive lens is arranged adjacent to the image side of the diaphragm and the Abbe number of the positive lens arranged adjacent to the image side of the diaphragm based on the d-line is set to v rp, the imaging lens of the above-described method preferably satisfies the conditional expression (10) shown below:

[0029] 34 < V rp < 87 (10).

[0030] When a positive lens is arranged adjacent to the object side of the diaphragm and the Abbe number of the positive lens arranged adjacent to the object side of the diaphragm based on the d-line is set to v fp, the imaging lens of the above-described method preferably satisfies the conditional expression (11) shown below:

[0031] 23 < v fp < 61 (11).

[0032] When a positive lens is arranged adjacent to the object side of the diaphragm and a lens Lffn with negative refractive power is arranged adjacent to the object side of the positive lens, and the Abbe number of the lens Lffn based on the d-line is set to v ffn, the imaging lens of the above-described method preferably satisfies the conditional expression (12) shown below:

[0033] 16 < v ffn < 100 (12).

[0034] Preferably, in a cross-section including the optical axis, when the radius of the circle passing through three points formed by the point on the optical axis of the lens surface and the two outermost points of the effective diameter is set to Rc of the lens surface, and the sign of Rc is set to positive when the point on the optical axis is closer to the object side than the center of the circle and negative when the point on the optical axis is closer to the image side than the center of the circle, the first lens group continuously includes a negative partial group and one positive lens in order from the object side to the image side, the negative partial group includes one or two negative lenses with the same sign of Rc of the object-side lens surface and the image-side lens surface, and at least one lens surface included in the negative partial group is an aspherical shape. The imaging lens of the above-described method preferably satisfies the conditional expressions (13) and (14) shown below:

[0035] 1.45 < N1nave < 2.3 (13)

[0036] 16 < v 1nave < 85 (14).

[0037] Among them, the average value of the refractive indices of all the lenses included in the negative lens group with respect to the d-line is set as N1nave, and the average value of the Abbe numbers based on the d-line of all the lenses included in the negative lens group is set as v1nave.

[0038] When the combined focal length of all the lenses on the object side of the aperture stop in the state of focusing on an infinitely distant object is set as fGf, and the combined focal length of all the lenses on the image side of the aperture stop in the state of focusing on an infinitely distant object is set as fGr, the imaging lens of the above-described method preferably satisfies the conditional expression (15) shown below:

[0039] -10 < fGf / fGr < 31 (15).

[0040] The lens surface of the second lens group closest to the image side is preferably convex.

[0041] Preferably, the imaging lens includes at least one lens surface having an inflection point. When the distance on the optical axis from the lens surface of the first lens group closest to the object side to the lens surface of the third lens group closest to the image side is set as DL, in the state of focusing on an infinitely distant object, at least one of the intersections of the lens surface having an inflection point and the optical axis is a specific intersection, and the specific intersection is within the range of 0.3×DL toward the image side from the intersection of the lens surface of the first lens group closest to the object side and the optical axis, or within the range of 0.3×DL toward the object side from the intersection of the lens surface of the third lens group closest to the image side and the optical axis.

[0042] When the refractive power of the lens surface having the above-described specific intersection is set as φa, and the refractive power of the imaging lens in the state of focusing on an infinitely distant object is set as φ, at least one of the lens surfaces having a specific intersection preferably satisfies the conditional expression (16) shown below:

[0043] -2 < φa / φ < 3 (16).

[0044] Another aspect of the present invention is an imaging device including the imaging lens of the above-described method.

[0045] In addition, "including ~" and "including ~" in this specification mean that, in addition to the cited constituent elements, it may also include lenses having substantially no refractive power, and optical elements other than lenses such as an aperture stop, a filter, and a cover glass, and structural parts such as a lens flange, a lens barrel, an imaging element, and a shake correction mechanism.

[0046] In this specification, the "group with positive refractive power" means that the group as a whole has positive refractive power. Similarly, the "group with negative refractive power" means that the group as a whole has negative refractive power. The "lens with positive refractive power" has the same meaning as a "positive lens". The "lens with negative refractive power" has the same meaning as a "negative lens". The "group" in this specification is not limited to a structure including multiple lenses, and may also be a structure including only one lens.

[0047] A compound aspherical lens (a lens in which a lens (e.g., a spherical lens) and an aspherical film formed on the 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 sign of the refractive power and the surface shape related to the lens including an aspherical surface use the sign and surface shape in the paraxial region.

[0048] The "entire system" in this specification refers to an imaging lens. The "focal length" used in conditional expressions is the paraxial focal length. Unless otherwise specified, the "distance on the optical axis" used in conditional expressions is the geometric distance. Unless otherwise specified, the values used in conditional expressions are the values based on the d-line in the state of focusing on an infinitely distant object.

[0049] The "d-line", "C-line", and "F-line" described in this specification 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), and the wavelength of the F-line is regarded as 486.13 nm (nanometers).

[0050] Advantages of the Invention

[0051] According to the present invention, it is possible to provide an imaging lens that shortens the total length of the lens system and has good optical performance, and an imaging device including the imaging lens. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] 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.

[0053] Figure 2 It shows Figure 1 The cross-sectional views of the structure and light beam in each state of the imaging lens.

[0054] Figure 3 It is a diagram for explaining Rc.

[0055] Figure 4 It is a diagram for explaining the notations of each conditional expression.

[0056] Figure 5 It is a diagram for explaining the notations of each conditional expression.

[0057] Figure 6 These are aberration diagrams of the imaging lens of Example 1.

[0058] Figure 7 This is a cross-sectional view showing the structure of the imaging lens of Example 2.

[0059] Figure 8 These are aberration diagrams of the imaging lens of Example 2.

[0060] Figure 9 This is a cross-sectional view showing the structure of the imaging lens of Example 3.

[0061] Figure 10 These are aberration diagrams of the imaging lens of Example 3.

[0062] Figure 11 This is a cross-sectional view showing the structure of the imaging lens of Example 4.

[0063] Figure 12 These are aberration diagrams of the imaging lens of Example 4.

[0064] Figure 13 This is a cross-sectional view showing the structure of the imaging lens of Example 5.

[0065] Figure 14 These are aberration diagrams of the imaging lens of Example 5.

[0066] Figure 15 This is a cross-sectional view showing the structure of the imaging lens of Example 6.

[0067] Figure 16 These are aberration diagrams of the imaging lens of Example 6.

[0068] Figure 17 This is a cross-sectional view showing the structure of the imaging lens of Example 7.

[0069] Figure 18 These are aberration diagrams of the imaging lens of Example 7.

[0070] Figure 19 This is a cross-sectional view showing the structure of the imaging lens of Example 8.

[0071] Figure 20 These are aberration diagrams of the imaging lens of Example 8.

[0072] Figure 21 This is a cross-sectional view showing the structure of the imaging lens of Example 9.

[0073] Figure 22 These are aberration diagrams of the imaging lens of Example 9.

[0074] Figure 23It is a cross-sectional view showing the structure of the imaging lens of Example 10.

[0075] Figure 24 They are aberration diagrams of the imaging lens of Example 10.

[0076] Figure 25 It is a cross-sectional view showing the structure of the imaging lens of Example 11.

[0077] Figure 26 They are aberration diagrams of the imaging lens of Example 11.

[0078] Figure 27 It is a cross-sectional view showing the structure of the imaging lens of Example 12.

[0079] Figure 28 They are aberration diagrams of the imaging lens of Example 12.

[0080] Figure 29 It is a cross-sectional view showing the structure of the imaging lens of Example 13.

[0081] Figure 30 They are aberration diagrams of the imaging lens of Example 13.

[0082] Figure 31 It is a cross-sectional view showing the structure of the imaging lens of Example 14.

[0083] Figure 32 They are aberration diagrams of the imaging lens of Example 14.

[0084] Figure 33 It is a cross-sectional view showing the structure of the imaging lens of Example 15.

[0085] Figure 34 They are aberration diagrams of the imaging lens of Example 15.

[0086] Figure 35 It is a cross-sectional view showing the structure of the imaging lens of Example 16.

[0087] Figure 36 They are aberration diagrams of the imaging lens of Example 16.

[0088] Figure 37 It is a cross-sectional view showing the structure of the imaging lens of Example 17.

[0089] Figure 38 They are aberration diagrams of the imaging lens of Example 17.

[0090] Figure 39 It is a cross-sectional view showing the structure of the imaging lens of Example 18.

[0091] Figure 40It is the aberration diagram of the imaging lens of Example 18.

[0092] Figure 41 It is a cross-sectional view showing the structure of the imaging lens of Example 19.

[0093] Figure 42 It is the aberration diagram of the imaging lens of Example 19.

[0094] Figure 43 It is a cross-sectional view showing the structure of the imaging lens of Example 20.

[0095] Figure 44 It is the aberration diagram of the imaging lens of Example 20.

[0096] Figure 45 It is a cross-sectional view showing the structure of the imaging lens of Example 21.

[0097] Figure 46 It is the aberration diagram of the imaging lens of Example 21.

[0098] Figure 47 It is a cross-sectional view showing the structure of the imaging lens of Example 22.

[0099] Figure 48 It is the aberration diagram of the imaging lens of Example 22.

[0100] Figure 49 It is a cross-sectional view showing the structure of the imaging lens of Example 23.

[0101] Figure 50 It is the aberration diagram of the imaging lens of Example 23.

[0102] Figure 51 It is a cross-sectional view showing the structure of the imaging lens of Example 24.

[0103] Figure 52 It is the aberration diagram of the imaging lens of Example 24.

[0104] Figure 53 It is a cross-sectional view showing the structure of the imaging lens of Example 25.

[0105] Figure 54 It is the aberration diagram of the imaging lens of Example 25.

[0106] Figure 55 It is a perspective view of the front side of the imaging device according to an embodiment.

[0107] Figure 56 It is a perspective view of the back side of the imaging device according to an embodiment.

[0108] Symbol Explanation

[0109] 1 - imaging lens, 2 - on - axis beam, 3 - beam, 3b - lower - side ray, 3c - chief ray, 30 - camera, 31 - camera body, 32 - shutter button, 33 - power button, 34 - operation unit, 35 - operation unit, 36 - display unit, 38 - imaging element, C - circle, CRA - angle, DL - distance, dL1St - distance, G1 - first lens group, G1n - negative sub - group, G2 - second lens group, G3 - third lens group, He - height, Hinf - height, L11~L34 - lenses, Lex - lens, O - center, P1 - specific intersection point, P2 - specific intersection point, P3 - specific intersection point, P4 - specific intersection point, Pa - point on the optical axis, Pe - point at the outermost end of the effective diameter, Pe1 - point at the outermost end of the effective diameter, Pe2 - point at the outermost end of the effective diameter, Pinf - inflection point, PP - optical component, Rc - radius, Sa - lens surface, Sim - image plane, St - aperture stop, Y - maximum image height, Z - optical axis, Zp - axis line, ωm - maximum half - viewing angle. Detailed implementation manners

[0110] Hereinafter, embodiments of the technology of the present invention will be described with reference to the accompanying drawings.

[0111] 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 it shows Figure 1 a cross - sectional view of the structure of the imaging lens and the beam. In Figure 2 in the upper part marked with "infinity", the state of focusing on an object at infinity is shown, and in the lower part marked with "0.150 m", the state of focusing on the nearest object with an object distance of 0.150 m is shown. In addition, in this specification, the distance from the lens surface closest to the object side of the imaging lens to the object is called the object distance. In Figure 2 it shows, as the beam, the on - axis beam 2 in the state of focusing on an object at infinity and the beam 3 with the maximum half - viewing angle ωm, and the on - axis beam and the beam with the maximum half - viewing angle in the state of focusing on the nearest object. In Figure 1 and Figure 2 the left side is the object side and the right side is the image side. Figure 1 and Figure 2 The examples shown correspond to the imaging lens of Embodiment 1 described later. Hereinafter, mainly with reference to Figure 1 it will be described.

[0112] In Figure 1An example is shown in which an imaging lens is applied to an imaging device and an optical component PP in the form of a parallel plate is disposed between the imaging lens and the image plane Sim. The optical component PP is a component assumed to be various filters and / or cover glass, etc. The various filters are a low-pass filter, an infrared cut-off filter, and / or a filter that cuts off a specific wavelength region, etc. The optical component PP is a component having no refractive power. The optical component PP can also be omitted to configure the imaging device.

[0113] The imaging lens of the present invention sequentially includes a first lens group G1 having a positive refractive power, a second lens group G2, and a third lens group G3 along the optical axis Z from the object side to the image side. By setting the sign of the refractive power of the first lens group G1 to be positive, the light beam emitted from the first lens group G1 can be made convergent light, which is therefore beneficial to shortening the overall length of the lens system.

[0114] During focusing, the first lens group G1 and the third lens group G3 are fixed relative to the image plane Sim, and the second lens group G2 moves along the optical axis Z. Hereinafter, the lens group that moves during focusing is referred to as the focusing group. Focusing is performed by moving the focusing group. In the imaging lens of the present invention, the focusing group includes the second lens group G2. By setting the second lens group G2 as the focusing group, compared with the structure in which the entire lens system moves during focusing, the weight of the focusing group can be reduced, and thus high-speed focusing can be performed.

[0115] As an example, Figure 1 each group of the imaging lens is configured as follows. The first lens group G1 sequentially includes four lenses L11 to L14 and an aperture stop St from the object side to the image side. The second lens group G2 sequentially includes four lenses L21 to L24 from the object side to the image side. The third lens group G3 includes one lens L31. In addition, Figure 1 the aperture stop St represents the position in the optical axis direction, rather than the size or shape. Figure 1 The bracket below the second lens group G2 and the arrow to the left indicate that the second lens group G2 is the focusing group and moves toward the object side when focusing from an infinite object to the nearest object.

[0116] In addition, in this specification, a "lens group" is a structural part of the imaging lens and is a part including at least one lens separated by an air interval that changes during focusing. During focusing, each lens group moves or is fixed as a unit, and the intervals between the lenses within each lens group remain unchanged. That is, in this specification, a group in which the interval from an adjacent group changes during focusing and the overall interval between adjacent lenses within itself does not change is defined as one lens group.

[0117] In the imaging lens of the present invention, the number of lenses included in the first lens group G1 can be configured to be 1 or more and 7 or less. When configured in this way, it is beneficial to shorten the total length of the lens system.

[0118] The second lens group G2 can be configured as a lens group with positive refractive power or as a lens group with negative refractive power.

[0119] The number of lenses included in the second lens group G2 can be configured to be 1 or more and 4 or less. When configured in this way, it is beneficial to shorten the total length of the lens system.

[0120] The lens surface of the second lens group G2 closest to the image side is preferably convex. When configured in this way, the emission angle of the light emitted from this lens surface can be reduced, so the generation of aberration can be suppressed, and in particular, the generation of field curvature can be suppressed.

[0121] The third lens group G3 can be configured as a lens group with positive refractive power or as a lens group with negative refractive power.

[0122] The number of lenses included in the third lens group G3 can be configured to be 1 or more and 4 or less. When configured in this way, it is beneficial to shorten the total length of the lens system.

[0123] The number of lenses included in the imaging lens can be configured to be 5 or more and 10 or less. By setting it to 5 or more, it is beneficial to achieve miniaturization while maintaining high performance. By setting it to 10 or less, it is beneficial to shorten the total length of the lens system.

[0124] The number of cemented lenses included in the imaging lens can be configured to be 0 or 1. When configured in this way, the degree of freedom is increased by reducing the cemented surfaces, so even if the number of lens elements is small, the aberration correction effect can be improved, and thus high performance can be achieved.

[0125] The imaging lens of the present invention is configured such that the lens closest to the object side is a negative meniscus lens, and at least one of the second lens from the object side and the third lens from the object side is a lens other than a negative meniscus lens. By setting the lens closest to the object side as a negative meniscus lens, it is beneficial for wide-angleization. By setting at least one of the second lens from the object side and the third lens from the object side as a lens other than a negative meniscus lens, the astigmatism that is over-corrected due to the negative meniscus lens can be corrected well. In addition, the "negative meniscus lens" in this specification refers to a meniscus lens with negative refractive power.

[0126] In Figure 1In the example, the above-mentioned "lens closest to the object side", "second lens from the object side", and "third lens from the object side" correspond to lens L11, lens L12, and lens L13, respectively. However, the above-mentioned "second lens from the object side" does not necessarily refer to the second lens from the object side of the first lens group G1, but refers to the second lens from the object side of the imaging lens. Similarly, the above-mentioned "third lens from the object side" also refers to the third lens from the object side of the imaging lens. For example, different from the example of Figure 1 in the imaging lens where the first lens group G1 includes two lenses, the above-mentioned "third lens from the object side" refers to the lens closest to the object side of the second lens group G2.

[0127] In the imaging lens of the present invention, the aperture stop St is arranged on the image side closer than the second lens from the object side. According to this structure, it is beneficial to the miniaturization of the overall lens system.

[0128] Preferably, one or two single lenses with negative refractive power and one or two single lenses with positive refractive power are arranged on the object side closer than the aperture stop St. And the number of lenses arranged on the object side closer than the aperture stop St is preferably 4 or less. By arranging the negative lens on the object side closer than the aperture stop St, it is beneficial to wide-angleization. In addition, by arranging the positive lens on the object side closer than the aperture stop St, it is beneficial to correct chromatic aberration. As described above, by being composed of single lenses, the degree of freedom increases, so it is beneficial to more effective aberration correction, especially beneficial to the correction of field curvature. By setting the number of lenses on the object side closer than the aperture stop St to 4 or less, it is beneficial to shorten the total length of the lens system.

[0129] Preferably, the positive lens is arranged adjacent to the object side of the aperture stop St. When configured in this way, it is beneficial to well correct the astigmatism generated by the lens closest to the object side.

[0130] Preferably, when the positive lens is arranged adjacent to the object side of the aperture stop St, the Lffn lens with negative refractive power is arranged adjacent to the object side of this positive lens arranged adjacent to the object side of the aperture stop St. That is, preferably, the Lffn lens with negative refractive power, the positive lens, and the aperture stop St are continuously arranged in sequence from the object side to the image side. By continuously arranging the negative lens on the positive lens adjacent to the object side of the aperture stop St, it is beneficial to well correct the axial chromatic aberration and magnification chromatic aberration. In Figure 1 the example, the Lffn lens corresponds to lens L13.

[0131] Preferably, the positive lens is arranged adjacent to the image side of the aperture stop St. When configured in this way, it is beneficial to well correct the residual astigmatism generated in the group composed of all the lenses on the object side closer than the aperture stop St.

[0132] Preferably, one or more and three or less negative lenses and two or more and four or less positive lenses are arranged on the image side with respect to the aperture stop St, and the number of lenses arranged on the image side with respect to the aperture stop St is seven or less. When configured in this way, the balance between the number of positive lenses and negative lenses can be achieved, so it is easy to achieve the correction balance between field curvature and chromatic aberration, which is beneficial to maintaining high performance. In addition, by setting the number of lenses on the image side with respect to the aperture stop St to seven or less, it is beneficial to shorten the total length of the lens system.

[0133] The imaging lens of the present invention may be configured to include an aspherical lens. In the technology of the present invention, in a cross-section including the optical axis Z, the radius of the circle passing through three points formed by the point on the optical axis of the lens surface and the two outermost points of the effective diameter is defined as Rc of the lens surface. In a spherical lens surface, the radius of curvature of the lens surface becomes Rc. In an aspherical lens surface, the approximate radius of curvature described below becomes Rc.

[0134] Reference Figure 3 , the approximate radius of curvature will be described. Figure 3 It is an explanatory diagram and is a diagram showing a cross-section including the optical axis Z. Figure 3 In the diagram of the lens LeX shown, the lens surface Sa on the right side is an aspherical shape. In Figure 3 , the point Pa on the optical axis of the lens surface Sa, the point Pe1 at the outermost end of the effective diameter on the upper side of the diagram of the lens surface Sa, and the point Pe2 at the outermost end of the effective diameter on the lower side of the diagram of the lens surface Sa are shown, and the circle C passing through these three points is represented by a double-dot dash line.

[0135] In the technology of the present invention, the radius of the circle C passing through the above three points is the approximate radius of curvature of the lens surface Sa, and is shown as the radius Rc in Figure 3 . The sign of the radius Rc is set to positive when the point Pa on the optical axis is closer to the object side than the center O of the circle C, and is set to negative when the point Pa on the optical axis is closer to the image side than the center O of the circle C. Similarly, for the Rc of a spherical lens surface, the sign is set to positive when the point on the optical axis of the lens surface is closer to the object side than the center O of the circle passing through the above three points, and is set to negative when the point on the optical axis of the lens surface is closer to the image side than the center O of the circle passing through the above three points.

[0136] In addition, the "point at the outermost end of the effective diameter" of the lens surface refers to the intersection of the outermost light ray passing through the lens surface among the light rays used in imaging and the lens surface. The "outer side" described here is the radial outer side centered on the optical axis Z, that is, the side away from the optical axis Z. For example, in Figure 2On the lens surface closest to the object in the upper part of the figure, when the lower light ray 3b is the outermost light ray passing through, the intersection point of the lower light ray 3b and this lens surface becomes the point at the outermost end of the effective diameter. The height of the point at the outermost end of the effective diameter from the optical axis Z is the effective radius, and twice the effective radius is the effective diameter.

[0137] The third lens group G3 preferably includes an aspherical lens. In this case, preferably, the lens surface on the object side included in the third lens group G3 is an aspherical shape, and the number of aspherical lenses with a negative sign for the Rc of this object-side lens surface is 1 or 2. When configured in this way, it is beneficial to balance wide-angle and miniaturization. Also, by using an aspherical lens, it is easy to optimize the curve of distortion aberration.

[0138] The first lens group G1 preferably successively includes a negative partial group G1n and one positive lens from the object side to the image side. The negative partial group G1n includes one or two negative lenses with the same sign for the Rc of the lens surface on the object side and the Rc of the lens surface on the image side. And at least one of the lens surfaces included in the negative partial group G1n is an aspherical shape. By adopting this structure, it is beneficial to correct distortion aberration and magnification chromatic aberration.

[0139] As an example, Figure 1 The negative partial group G1n of the imaging lens includes one lens, the meniscus-shaped negative lens L11. The Rc of both the lens surface on the object side and the lens surface on the image side of the lens L11 is positive, and both the lens surface on the object side and the lens surface on the image side of the lens L11 are aspherical shapes.

[0140] The imaging lens of the present invention preferably includes at least one lens surface having an inflection point. An inflection point refers to a point where the surface shape switches from a convex shape to a concave shape or from a concave shape to a convex shape, that is, a point where the sign of the radius of curvature changes. By having an inflection point on the lens surface, the refractive power of the peripheral part of the lens can be determined without depending on the refractive power in the paraxial region.

[0141] The imaging lens includes a lens surface having an inflection point, and at least one of the intersections of the lens surface having an inflection point with the optical axis Z is preferably a specific intersection described below. Here, the distance on the optical axis from the lens surface closest to the object side of the first lens group G1 to the lens surface closest to the image side of the third lens group G3 is defined as DL. The specific intersection refers to the intersection of the lens surface having an inflection point with the optical axis Z, and in the state of focusing on an infinite object, it is within the range of 0.3×DL from the intersection of the lens surface closest to the object side of the first lens group G1 with the optical axis Z toward the image side or within the range of 0.3×DL from the intersection of the lens surface closest to the image side of the third lens group G3 with the optical axis Z toward the object side. In addition, in this specification, the range "from ~ to ~" means a range including the "~" part. On the lens surface close to the object side and the lens surface close to the image side, the light beams of each viewing angle are separated. Therefore, by making these surfaces have inflection points, it is easy to well correct spherical aberration and effectively correct aberrations such as field curvature while doing so.

[0142] As an example, in Figure 4 shows Figure 1 a cross-sectional view of the imaging lens, and shows the above-mentioned distance DL in this imaging lens. And, in Figure 4 also shows the range of 0.3×DL from the intersection of the lens surface closest to the object side of the first lens group G1 with the optical axis Z toward the image side and the range of 0.3×DL from the intersection of the lens surface closest to the image side of the third lens group G3 with the optical axis Z toward the object side. In the example of Figure 4 , the object-side surface of lens L11, the image-side surface of lens L21, the object-side surface of lens L24, the image-side surface of lens L24, and the image-side surface of lens L31 have inflection points. Among them, the intersections of the four surfaces composed of the object-side surface of lens L11, the object-side surface of lens L24, the image-side surface of lens L24, and the image-side surface of lens L31 with the optical axis Z are specific intersections P1, P2, P3, and P4. The intersection of the image-side surface of lens L21 with the optical axis Z is outside the above range, so it is not a specific intersection.

[0143] The preferred structure of the imaging lens of the present invention related to the conditional expressions is described below. In the following description of the conditional expressions, to avoid redundancy, the same notations are used for the parts with the same definitions, and the repeated description of the notations is omitted. And, hereinafter, to avoid redundancy, the "imaging lens of the present invention" is also simply referred to as the "imaging lens".

[0144] The imaging lens preferably satisfies the following conditional expression (1). Here, the sum of the distance on the optical axis from the lens surface closest to the object side of the first lens group G1 to the lens surface closest to the image side of the third lens group G3 and the back focal length of the entire system in terms of air equivalent distance is defined as TL. The maximum image height is defined as Y. As an example, in Figure 2The maximum image height Y is shown. By preventing the corresponding value of conditional expression (1) from falling below the lower limit value, it is beneficial for ensuring the number of lens elements required for aberration correction. By preventing the corresponding value of conditional expression (1) from exceeding the upper limit value, miniaturization becomes easier.

[0145] 1 < TL / Y < 4.5 (1)

[0146] To obtain better characteristics, the lower limit value of conditional expression (1) is more preferably set to 1.1, further preferably to 1.2, and further preferably to 1.3. To obtain better characteristics, the upper limit value of conditional expression (1) is more preferably set to 4.3, further preferably to 4.2, and even more preferably to 4.1.

[0147] The imaging lens preferably satisfies the following conditional expression (2). Here, 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. As an example, in Figure 2 the above-mentioned maximum half-angle ωm is shown. Tan is the tangent. By preventing the corresponding value of conditional expression (2) from falling below the lower limit value, pincushion aberration can be reduced. As a result, when performing image processing on the image captured by the imaging lens, it is easy to set the deterioration of the image quality after image processing correction to an acceptable level. By preventing the corresponding value of conditional expression (2) from exceeding the upper limit value, the image height position with respect to the incident angle becomes lower, so the lens diameter can be reduced, which is beneficial for the miniaturization of the entire optical system.

[0148] -0.18 < (Y - f×tanωm) / (f×tanωm) < -0.02 (2)

[0149] To obtain even better characteristics, the lower limit value of conditional expression (2) is more preferably set to -0.175, further preferably to -0.16, further preferably to -0.145, and further preferably to -0.14. To obtain even better characteristics, the upper limit value of conditional expression (2) is more preferably set to -0.03, further preferably to -0.04, further preferably to -0.05, and further preferably to -0.06.

[0150] The imaging lens preferably satisfies the following conditional expression (3). Here, the unit of ωm is degrees. By preventing the corresponding value of conditional expression (3) from falling below the lower limit value, the added value as an ultra-wide-angle lens system becomes larger. By preventing the corresponding value of conditional expression (3) from exceeding the upper limit value, it is easy to balance the miniaturization of the filter diameter and good optical performance.

[0151] 47 < ωm < 60 (3)

[0152] In order to obtain better characteristics, the lower limit value of conditional expression (3) is more preferably set to 48, further preferably 49, further preferably 50, and further preferably 51. In order to obtain better characteristics, the upper limit value of conditional expression (3) is more preferably set to 59, further preferably 58, further preferably 57, and further preferably 56.

[0153] When the focal length of the first lens group G1 is set to fG1, 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 value, it is easy to shorten the overall length of the lens system, which is thus beneficial for miniaturization. By preventing the corresponding value of conditional expression (4) from exceeding the upper limit value, it is easy to achieve a wide angle.

[0154] 0.01 < f / fG1 < 1.6 (4)

[0155] In order to obtain better characteristics, the upper limit value of conditional expression (4) is more preferably set to 1.55, and further preferably 1.5.

[0156] The imaging lens preferably satisfies the following conditional expression (5). Here, the distance on the optical axis from the lens surface closest to the object side of the first lens group G1 to the aperture stop St in the state of focusing on an infinitely distant object is set to dL1St. As an example, Figure 4 shows the above-mentioned distance dL1St. By preventing the corresponding value of conditional expression (5) from falling below the lower limit value, it is beneficial to reduce the incident angle of the off-axis chief ray on the image plane Sim. By preventing the corresponding value of conditional expression (5) from exceeding the upper limit value, it is beneficial to shorten the overall length of the lens system.

[0157] 0.1 < dL1St / Y < 2.1 (5)

[0158] In order to obtain better characteristics, the lower limit value of conditional expression (5) is more preferably set to 0.2, and further preferably 0.3. In order to obtain better characteristics, the upper limit value of conditional expression (5) is more preferably set to 1.9, and further preferably 1.7.

[0159] The imaging lens preferably satisfies the following conditional expression (6). Here, the angle formed by the chief ray of the maximum image height incident on the image plane Sim and the axis parallel to the optical axis Z in the state of focusing on an infinitely distant object is set to CRA. The unit of CRA is degrees. In Figure 5 shows a partial enlarged view of the upper parts of the lens L31, the optical component PP, and the image plane Sim of the imaging lens including Figure 1 and, as an example, shows the above-mentioned angle CRA. In Figure 5In this figure, the chief ray 3c of the maximum half field of view ω incident on the image plane Sim is shown as a solid line, and the axis Zp passing through the intersection of the chief ray 3c and the image plane Sim and parallel to the optical axis Z is shown as a dashed line. The chief ray 3c of the maximum half field of view ωm corresponds to the chief ray of the above maximum image height. By ensuring that the corresponding value of conditional expression (6) does not fall below the lower limit value, the distance from the aperture stop St to the image plane Sim can be shortened, which is beneficial for shortening the total length of the lens system. By ensuring that the corresponding value of conditional expression (6) does not exceed the upper limit value, the back focal length can be extended, making it easier to insert various filters such as an infrared cut-off filter.

[0160] 16 < |CRA| < 69 (6)

[0161] To obtain better characteristics, the lower limit value of conditional expression (6) is more preferably set to 18, and further preferably to 20. To obtain better characteristics, the upper limit value of conditional expression (6) is more preferably set to 67, and further preferably to 65.

[0162] When the back focal length of the entire system in terms of air equivalent distance is set as Bf, the imaging lens preferably satisfies the following conditional expression (7). The back focal length Bf of the entire system in terms of 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. By ensuring that the corresponding value of conditional expression (7) does not fall below the lower limit value, it is easier to insert various filters such as an infrared cut-off filter. By ensuring that the corresponding value of conditional expression (7) does not exceed the upper limit value, it is beneficial for ensuring the number of lens elements required for aberration correction.

[0163] 0.06 < Bf / TL < 0.3 (7)

[0164] To obtain better characteristics, the lower limit value of conditional expression (7) is more preferably set to 0.08, and further preferably to 0.1. To obtain better characteristics, the upper limit value of conditional expression (7) is more preferably set to 0.28, and further preferably to 0.26.

[0165] The imaging lens preferably satisfies the following conditional expression (8). Here, the unit of f is set as mm (millimeter). The open F value of the imaging lens in the state of focusing on an infinitely distant object is set as Fno. By ensuring that the corresponding value of conditional expression (8) does not fall below the lower limit value, it is possible to ensure the brightness that can maintain the commercial viability. By ensuring that the corresponding value of conditional expression (8) does not exceed the upper limit value, it is beneficial for balancing the maintenance of high performance and the ensuring of the required brightness.

[0166] 1.7 < f / Fno < 4.1 (8)

[0167] In order to obtain better characteristics, the lower limit value of conditional expression (8) is more preferably set to 1.8, and further preferably to 1.9. In order to obtain better characteristics, the upper limit value of conditional expression (8) is more preferably set to 3.9, and further preferably to 3.7.

[0168] When the focal length of the second lens group G2 is set to fG2, 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 value, the required refractive power of the second lens group G2 can be ensured, and thus the movement amount during focusing can be reduced. As a result, it is beneficial to miniaturize the lens system. By preventing the corresponding value of conditional expression (9) from exceeding the upper limit value, the aberration variation during focusing can be suppressed, and thereby the optical performance variation when the object distance changes can be suppressed.

[0169] 0.24 < |f / fG2| < 2.4 (9)

[0170] In order to obtain better characteristics, the lower limit value of conditional expression (9) is more preferably set to 0.26, and further preferably to 0.28. In order to obtain better characteristics, the upper limit value of conditional expression (9) is more preferably set to 2.2, and further preferably to 2.

[0171] In a structure where a positive lens is disposed adjacent to the image side of the aperture stop St, the imaging lens preferably satisfies the following conditional expression (10). Here, the Abbe number of the positive lens disposed adjacent to the image side of the aperture stop St with respect to the d-line is set to vrp. By satisfying conditional expression (10), it is easy to correct the lateral chromatic aberration and the axial chromatic aberration.

[0172] 34 < vrp < 87 (10)

[0173] In order to obtain better characteristics, the lower limit value of conditional expression (10) is more preferably set to 36, and further preferably to 38. In order to obtain better characteristics, the upper limit value of conditional expression (10) is more preferably set to 85, and further preferably to 83.

[0174] In a structure where a positive lens is disposed adjacent to the object side of the aperture stop St, the imaging lens preferably satisfies the following conditional expression (11). Here, the Abbe number of the positive lens disposed adjacent to the object side of the aperture stop St with respect to the d-line is set to vfp. By satisfying conditional expression (11), it is easy to correct the lateral chromatic aberration and the axial chromatic aberration.

[0175] 23 < vfp < 61 (11)

[0176] In order to obtain better characteristics, the lower limit value of conditional expression (11) is more preferably set to 25, and further preferably to 27. In order to obtain better characteristics, the upper limit value of conditional expression (11) is more preferably set to 59, and further preferably to 57.

[0177] In a structure in which an Lffn lens having a negative refractive power is disposed adjacent to the object side of a positive lens and a positive lens is disposed adjacent to the object side of the positive lens, the imaging lens preferably satisfies the following conditional expression (12). Here, the Abbe number of the Lffn lens based on the d line is set as vffn. By satisfying conditional expression (12), it is easy to correct the longitudinal chromatic aberration and the lateral chromatic aberration.

[0178] 16 < vffn < 100 (12)

[0179] In order to obtain better characteristics, the lower limit value of conditional expression (12) is more preferably set to 17, further preferably 18, and still further preferably 35. In order to obtain better characteristics, the upper limit value of conditional expression (12) is more preferably set to 98, further preferably 96, and still further preferably 45.

[0180] In a structure in which the first lens group G1 sequentially and continuously includes the above-described negative partial group G1n and one positive lens from the object side closest to the object side toward the image side, the imaging lens preferably satisfies the following conditional expression (13). Here, the average value of the refractive indices of all the lenses included in the negative partial group G1n with respect to the d line is set as N1nave. By preventing the corresponding value of conditional expression (13) from becoming below the lower limit value, it is possible to easily obtain the required refractive power without reducing the absolute value of the curvature radius of the lens surface on the image side of the lenses included in the negative partial group G1n. As a result, it is possible to increase the absolute value of the curvature radius of the lens surface on the image side, and thus the workability can be improved. By preventing the corresponding value of conditional expression (13) from becoming above the upper limit value, a reduction in the transmittance can be suppressed.

[0181] 1.45 < N1nave < 2.3 (13)

[0182] In order to obtain better characteristics, the lower limit value of conditional expression (13) is more preferably set to 1.5, and further preferably 1.55. In order to obtain better characteristics, the upper limit value of conditional expression (13) is more preferably set to 2.2, and further preferably 2.1.

[0183] In a structure in which the first lens group G1 sequentially and continuously includes the above-described negative partial group G1n and one positive lens from the object side closest to the object side toward the image side, the imaging lens preferably satisfies the following conditional expression (14). Here, the average value of the Abbe numbers of all the lenses included in the negative partial group G1n based on the d line is set as v1nave. By preventing the corresponding value of conditional expression (14) from becoming below the lower limit value, it is easy to correct the longitudinal chromatic aberration. By preventing the corresponding value of conditional expression (14) from becoming above the upper limit value, the use of a soft material that is likely to produce scratches can be suppressed, and thus it is beneficial to improve the appearance quality.

[0184] 16 < v1nave < 85 (14)

[0185] In order to obtain better characteristics, the lower limit value of conditional expression (14) is more preferably set to 17, further preferably 18, and even more preferably 25. In order to obtain better characteristics, the upper limit value of conditional expression (14) is more preferably set to 82, further preferably 72, and even more preferably 35.

[0186] In the structure where the first lens group G1 sequentially and continuously includes the above-mentioned negative partial group G1n and one positive lens from the object side closest to the object side to the image side, the imaging lens more preferably satisfies conditional expressions (13) and (14) simultaneously.

[0187] The imaging lens preferably satisfies the following conditional expression (15). Among them, the combined focal length of all lenses closer to the object side than the aperture stop St in the state of focusing on an infinitely distant object is set as fGf. The combined focal length of all lenses closer to the image side than the aperture stop St in the state of focusing on an infinitely distant object is set as fGr. By preventing the corresponding value of conditional expression (15) from falling below the lower limit value, it is beneficial to achieve a good balance between the refractive power on the object side of the aperture stop St and the refractive power on the image side of the aperture stop St, and it is easy to ensure the back focal length. By preventing the corresponding value of conditional expression (15) from exceeding the upper limit value, it is beneficial to achieve a good balance between the refractive power on the object side of the aperture stop St and the refractive power on the image side of the aperture stop St, and it is easy to correct the barrel distortion aberration.

[0188] -10 < fGf / fGr < 31 (15)

[0189] In order to obtain better characteristics, the lower limit value of conditional expression (15) is more preferably set to -8, further preferably -6, and even more preferably 1.7. In order to obtain better characteristics, the upper limit value of conditional expression (15) is more preferably set to 29, further preferably 27, and even more preferably 6.

[0190] In the structure having the above-mentioned specific intersection point, at least one of the lens surfaces having the specific intersection point preferably satisfies the following conditional expression (16). In addition, the "lens surface having the specific intersection point" refers to the lens surface whose intersection point with the optical axis Z becomes the specific intersection point. Among them, the refractive power of the lens surface having the specific intersection point is set as φa. The refractive power of the imaging lens in the state of focusing on an infinitely distant object is set as φ. φ = 1 / f. By satisfying conditional expression (16), the refractive power of the lens surface having the specific intersection point and the inflection point will not become too strong, so it is possible to suppress the processing sensitivity and the sensitivity during assembly from becoming too high. And it is beneficial to correct the spherical aberration and the field curvature well.

[0191] -2 < φa / φ < 3 (16)

[0192] In addition, when the refractive index of the medium on the incident side of the lens surface is Nin, the refractive index of the medium on the exit side of the lens surface is Nout, and the radius of curvature of the lens surface is R, the refractive power φa of the lens surface is expressed by φa = (Nout - Nin) / R.

[0193] In order to obtain better characteristics, the lower limit value of conditional expression (16) is more preferably set to -1, and further preferably to -0.8. In order to obtain better characteristics, the upper limit value of conditional expression (16) is more preferably set to 2.5, and further preferably to 2.2.

[0194] In the structure having the above-mentioned specific intersection point, at least one of the lens surfaces having the specific intersection point preferably satisfies the following conditional expression (17). Among them, in each lens surface, the height of the inflection point from the optical axis Z is set as Hinf, and the height of the point at the outermost end of the effective diameter from the optical axis Z is set as He. Hinf and He take positive values. As described above, He corresponds to the effective radius. In addition, when one lens surface has a plurality of inflection points, it is sufficient that at least one inflection point satisfies conditional expression (17). As an example, in Figure 4 the inflection point Pinf related to the object-side lens surface of the lens L11, the above-mentioned height Hinf, the point Pe at the outermost end of the effective diameter, and the above-mentioned height He are shown. By preventing the corresponding value of conditional expression (17) from becoming below the lower limit value, an inflection point can be provided at a position far from the optical axis Z, which is advantageous for effectively correcting field curvature while satisfactorily correcting spherical aberration. By preventing the corresponding value of conditional expression (17) from becoming above the upper limit value, it is advantageous for correcting field curvature.

[0195] 0.3 < Hinf / He < 0.99 (17)

[0196] In order to obtain better characteristics, the lower limit value of conditional expression (17) is more preferably set to 0.4, and further preferably to 0.55. In order to obtain better characteristics, the upper limit value of conditional expression (17) is more preferably set to 0.98.

[0197] The imaging lens preferably satisfies the following conditional expression (18). By preventing the corresponding value of conditional expression (18) from becoming below the lower limit value, it is advantageous for ensuring the number of lens elements required for aberration correction. By preventing the corresponding value of conditional expression (18) from becoming above the upper limit value, miniaturization is facilitated.

[0198] 11 < TL / f < 6 (18)

[0199] In order to obtain better characteristics, the lower limit value of conditional expression (18) is more preferably set to 1.25, and further preferably to 1.5. In order to obtain better characteristics, the upper limit value of conditional expression (18) is more preferably set to 5.5, and further preferably to 5.1.

[0200] The imaging lens preferably satisfies the following conditional expression (19). By satisfying the conditional expression (19), it is beneficial to suppress the generation of aberrations and to reduce the incident angle of the off-axis chief ray to the image plane Sim.

[0201] -1.1 < f / fGf < 1.3 (19)

[0202] In order to obtain better characteristics, the lower limit value of the conditional expression (19) is more preferably set to -0.9, and further preferably to -0.7. In order to obtain better characteristics, the upper limit value of the conditional expression (19) is more preferably set to 1.1, and further preferably to 0.9.

[0203] The imaging lens preferably satisfies the following conditional expression (20). By satisfying the conditional expression (20), it is beneficial to suppress the generation of aberrations and to reduce the incident angle of the off-axis chief ray to the image plane Sim.

[0204] -0.4 < f / fGr < 1.4 (20)

[0205] In order to obtain better characteristics, the lower limit value of the conditional expression (20) is more preferably set to -0.2, and further preferably to 0. In order to obtain better characteristics, the upper limit value of the conditional expression (20) is more preferably set to 1.2, and further preferably to 1.

[0206] The imaging lens preferably satisfies the following conditional expression (21). Among them, the average value of the Abbe numbers of all negative lenses on the object side with respect to the aperture stop St is set as v Gfaven. The average value of the Abbe numbers of all positive lenses on the object side with respect to the aperture stop St is set as v Gfavep. The conditional expression (21) is a conditional expression for well correcting chromatic aberration in the entire wavelength region of the visible light region. By preventing the corresponding value of the conditional expression (21) from falling below the lower limit value, the correction effect of the residual secondary spectrum can be improved. By preventing the corresponding value of the conditional expression (21) from exceeding the upper limit value, the correction effect of the primary chromatic aberration can be improved.

[0207] 0.6 < |v Gfaven - v Gfavep| < 47 (21)

[0208] In order to obtain better characteristics, the lower limit value of the conditional expression (21) is more preferably set to 0.8, further preferably to 1, and even more preferably to 6. In order to obtain better characteristics, the upper limit value of the conditional expression (21) is more preferably set to 45, further preferably to 43, and even more preferably to 30.

[0209] The imaging lens preferably satisfies the following conditional expression (22). Herein, the average value of the Abbe numbers of all negative lenses on the image side with respect to the aperture stop St based on the d-line is defined as vGraven. The average value of the Abbe numbers of all positive lenses on the image side with respect to the aperture stop St based on the d-line is defined as vGravep. The conditional expression (22) is a conditional expression for well correcting chromatic aberration in the entire wavelength range of the visible region. By preventing the corresponding value of the conditional expression (22) from falling below the lower limit value, the correction effect of the residual secondary spectrum can be improved. By preventing the corresponding value of the conditional expression (22) from exceeding the upper limit value, the correction effect of the primary chromatic aberration can be improved.

[0210] 4 < |vGraven - vGravep| < 52 (22)

[0211] In order to obtain better characteristics, the lower limit value of the conditional expression (22) is more preferably set to 6, further preferably to 8, and even further preferably to 30. In order to obtain better characteristics, the upper limit value of the conditional expression (22) is more preferably set to 50, further preferably to 49, and even further preferably to 48.

[0212] The imaging lens preferably satisfies the following conditional expression (23). By preventing the corresponding value of the conditional expression (23) from falling below the lower limit value, it is easy to maintain high performance and miniaturize. By preventing the corresponding value of the conditional expression (23) from exceeding the upper limit value, it is easy to balance ensuring a small F-number and wide-angleization.

[0213] 0.8 < Fno / tanωm < 3.2 (23)

[0214] In order to obtain better characteristics, the lower limit value of the conditional expression (23) is more preferably set to 1, further preferably to 1.2. In order to obtain better characteristics, the upper limit value of the conditional expression (23) is more preferably set to 3, further preferably to 2.8.

[0215] When the focal length of the third lens group G3 is set to fG3, the imaging lens preferably satisfies the following conditional expression (24). By preventing the corresponding value of the conditional expression (24) from falling below the lower limit value, the incident angle of the off-axis chief ray on the image plane Sim can be reduced, and thus peripheral light reduction can be suppressed. By preventing the corresponding value of the conditional expression (24) from exceeding the upper limit value, it is easy to suppress distortion aberration.

[0216] -2.4 < f / fG3 < 1 (2)4

[0217] In order to obtain better characteristics, the lower limit value of the conditional expression (24) is more preferably set to -2.2, further preferably to -2. In order to obtain better characteristics, the upper limit value of the conditional expression (24) is more preferably set to 0.8, further preferably to 0.6.

[0218] The imaging lens preferably satisfies the following conditional expression (25). Conditional expression (25) is an expression related to the second lens group G2 that constitutes the focusing group. Herein, the lateral magnification of the second lens group G2 in the state of focusing on an object at infinity is set as β foc. The lateral magnification of the third lens group G3 in the state of focusing on an object at infinity is set as β focR. By preventing the corresponding value of conditional expression (25) from falling below the lower limit value, the movement amount of the image plane Sim with respect to the movement amount in the optical axis direction of the second lens group G2 can be increased. Therefore, the movement amount of the second lens group G2 during focusing can be reduced, which is beneficial for shortening the overall length of the lens system. By preventing the corresponding value of conditional expression (25) from exceeding the upper limit value, the movement amount of the image plane Sim with respect to the movement amount in the optical axis direction of the second lens group G2 can be reduced. Therefore, the control during focusing becomes easier, which is beneficial for accurate focusing.

[0219] 0.4 < |(1 - βfoc 2 ) × βfocR 2 | < 3.8 (25)

[0220] To obtain better characteristics, the lower limit value of conditional expression (25) is more preferably set to 0.45, and further preferably to 0.5. To obtain better characteristics, the upper limit value of conditional expression (25) is more preferably set to 3.6, and further preferably to 3.4.

[0221] The imaging lens preferably satisfies the following conditional expression (26). Herein, the unit of Y is set as mm (millimeter). By preventing the corresponding value of conditional expression (26) from falling below the lower limit value, it is easy to ensure the number of pixels of the imaging element used in combination with the imaging lens, which can achieve a high resolution. By preventing the corresponding value of conditional expression (26) from exceeding the upper limit value, miniaturization is facilitated.

[0222] 2 < Y < 17 (26)

[0223] To obtain better characteristics, the lower limit value of conditional expression (26) is more preferably set to 3, further preferably to 4, and even further preferably to 5. To obtain better characteristics, the upper limit value of conditional expression (26) is more preferably set to 16, further preferably to 15, and further preferably to 8.

[0224] In addition, Figure 1 The example shown is just 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 each lens group can be different from that in the Figure 1 example. The signs of the refractive powers of the second lens group G2 and the third lens group G3 can also be different from those in the Figure 1 example.

[0225] Figure 1The imaging lens in the example includes, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2 having a positive refractive power, and a third lens group G3 having a negative refractive power. According to this refractive power configuration, it becomes a telephoto lens system, which is advantageous for miniaturization.

[0226] As shown in the embodiments described later, the imaging lens of the present invention can be configured to include, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens group G3 having a negative refractive power. This structure also becomes a telephoto lens system, which is advantageous for miniaturization.

[0227] As shown in another embodiment described later, the imaging lens of the present invention can be configured to include, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens group G3 having a positive refractive power. By setting only the second lens group G2, which is the focusing group, to a group having a negative refractive power, the second lens group G2 can have a relatively strong refractive power, so it is easy to reduce the movement amount of the focusing group during focusing.

[0228] As shown in yet another embodiment described later, the imaging lens of the present invention can be configured to include, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2 having a positive refractive power, and a third lens group G3 having a positive refractive power. By setting all lens groups to groups having a positive refractive power, it is advantageous for miniaturization.

[0229] In the imaging lens of the present invention, the lens surface provided with an aspherical shape can be a surface different from the Figure 1 example. The aspherical shape can be formed by grinding or molding. And, as the lens having an aspherical shape, a compound aspherical lens can be used. The material of the lens can be glass or resin.

[0230] In the imaging lens of the present invention, in order to correct chromatic aberration, any lens group can be configured to have a refractive index distribution type lens such as a GRIN lens (Gradient Index Lens) or a diffractive optical element.

[0231] In the imaging lens of the present invention, in order to maintain the transmittance in a wide wavelength region, an antireflection film can be applied to the lens. The antireflection film can suppress reflection in all wavelength regions used, or can select several used wavelength regions and only suppress reflection in that wavelength region. As the antireflection film, a special coating can be used, and the special coating is configured to form nanostructured bodies in a moth-eye shape on the lens surface to suppress reflection.

[0232] The above-described preferred structures and the structures that can be implemented can be arbitrarily combined within a non-contradictory range, and are preferably selectively adopted according to the required specifications.

[0233] As an example, a preferred embodiment of the imaging lens of the present invention includes, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2, and a third lens group G3. During focusing, the first lens group G1 and the third lens group G3 are fixed with respect to the image plane Sim, the second lens group G2 moves along the optical axis Z, the lens closest to the object side is a negative meniscus lens, and at least one of the second lens from the object side and the third lens from the object side is a lens other than a negative meniscus lens. The aperture stop St is disposed on the image side of the second lens from the object side and satisfies the above-described conditional expressions (1) and (2).

[0234] Next, embodiments of the imaging lens of the present invention will be described with reference to the accompanying drawings. In addition, the reference symbols of the lens groups and lenses in the cross-sectional views of the respective embodiments are used independently for each embodiment to avoid complication of the description and the drawings due to an increase in the number of digits of the reference symbols. Therefore, even if the same reference symbol is marked in the drawings of different embodiments, it is not necessarily the same structure.

[0235] [Embodiment 1]

[0236] A cross-sectional view of the structure of the imaging lens of Embodiment 1 is shown in Figure 1 As described above for the illustration method and structure, 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 first lens group G1 having a positive refractive power, a second lens group G2 having a positive refractive power, and a third lens group G3 having a negative refractive power. The focusing group includes the second lens group G2, and when focusing from an infinite object to the nearest object, the focusing group moves toward the object side along the optical axis Z.

[0237] 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 during focusing are shown in Table 3, and the aspherical coefficients are shown in Tables 4A and 4B.

[0238] The table of the basic lens data is described below. In the column "Sn", the surface numbers are shown when the surface closest to the object side is set as the first surface and the numbers increase sequentially toward the image side. In the column "R", the curvature radii of the respective surfaces are shown. In the column "D", the surface intervals on the optical axis between the respective surfaces and the surfaces adjacent to them on the image side are shown. In the column "Nd", the refractive indices of the respective lenses with respect to the d-line are shown. In the column "vd", the Abbe numbers of the respective lenses based on the d-line are shown. In the column "ED", the effective diameters of the respective surfaces are shown. The half value of the effective diameter corresponds to the height He of the point at the outermost end of the effective diameter from the optical axis Z. In the column "Hinf", for the surface having an inflection point, the height of the inflection point from the optical axis Z in each surface is shown. In the column "Hinf", for the surface having a plurality of inflection points, the values related to the respective inflection points are separated by " / ". In the column "Hinf", for the surface having an inflection point and not having a specific intersection point, the value is shown in parentheses as a reference.

[0239] 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 as positive and the sign of the curvature radius of the surface with the convex shape facing the image side is set as negative. In the column of the surface number corresponding to the aperture stop St, the surface number and the term "(St)" are entered. The optical component PP is also shown in the table of the basic lens data. The value in the bottom row of the D column of 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 in [] and entered in the column of the surface interval.

[0240] In Table 2, the focal length f of the entire system based on the d-line, the back focal length Bf in terms of the air-converted distance, the open F value Fno, and the maximum full viewing angle 2ωm are shown. The [°] in the column of the maximum full viewing angle indicates that the unit is degrees. The values in the state of focusing on an object at infinity are shown in Table 2.

[0241] In Table 3, in the column "Infinity", the variable surface intervals in the state of focusing on an object at infinity are shown. The object distance of the nearest object is shown in the uppermost row of the rightmost column, and the variable surface intervals in the state of focusing on the nearest object are shown in the columns below it. For example, in Example 1, the object distance of the nearest object is 0.150 m (meter).

[0242] 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 Tables 4A and 4B, in the row of Sn, the surface numbers of the aspherical surfaces are shown, and in the rows of KA and Am (m = 3, 4, 5,..., 20), the values of the aspherical coefficients regarding the respective aspherical surfaces are shown. The "E±n" (n: integer) of the values of the aspherical coefficients in Tables 4A and 4B means "×10 ±n ". KA and Am are the aspherical coefficients in the aspherical formula represented by the following formula.

[0243] Zd = C × h 2 / {1 + (1 - KA × C 2 × h 2 ) 1 / 2}+ ∑Am × h m

[0244] Wherein,

[0245] Zd: Aspherical depth (the length of the perpendicular line dropped from a point on the aspherical surface at height h to the plane tangent to the aspherical vertex and perpendicular to the optical axis Z);

[0246] h: Height (the distance from the optical axis Z to the lens surface);

[0247] C: Reciprocal of the paraxial radius of curvature; and

[0248] KA, Am: Aspherical coefficients,

[0249] The ∑ in the aspherical formula refers to the sum related to m.

[0250] In the data of each table, degrees are used as the unit of angle, and mm (millimeter) is used as the unit of length other than the object distance. However, the optical system can be used in an enlarged or reduced scale, so other appropriate units can also be used. And, the values rounded to a preset number of digits are recorded in each of the following tables.

[0251] [Table 1]

[0252] Example 1

[0253] Sn R D Nd vd ED Hinf *1 915.7538 1.0071 1.68948 31.02 10.99 3.83 *2 4.5853 2.5594 7.72 3 15.1597 1.7544 1.85025 30.05 7.24 4 -27.9262 0.8164 6.66 *5 -5.8277 1.1892 1.85135 40.10 6.30 *6 -8.2465 0.0998 6.08 7 14.4808 1.4151 1.67790 55.35 5.94 8 -50.3582 1.2504 5.78 9(St) ∞ DD[9] *10 9.6381 1.6270 1.80139 45.45 5.22 *11 -32.9640 1.3025 5.41 (2.64) 12 -9.8080 1.9825 1.43875 94.66 5.66 13 -4.8635 0.7500 1.95906 17.47 6.28 14 -18.6329 0.1001 6.29 *15 -2243.6411 1.8566 1.80139 45.45 7.48 0.14 / 0.79 / 1.48 / 3.88 *16 -6.2256 DD

[16] 8.28 2.54 / 4.18 *17 -15.8604 1.0000 1.68948 31.02 8.69 *18 4300.9086 1.7041 9.50 0.77 19 ∞ 1.3800 1.51680 64.20 11.03 20 ∞ 0.4982

[0254] [Table 2]

[0255] Example 1

[0256] f 5.94 Bf 3.11 Fno 1.85 2ωm[°] 108.0

[0257] [Table 3]

[0258] Example 1

[0259] Infinity 0.150m DD[9] 1.3500 1.1775 DD

[16] 1.4013 1.5738

[0260] [Table 4A]

[0261] Example 1

[0262]

[0263] [Table 4B]

[0264] Example 1

[0265] Sn 17 18 KA -2.1431588E-01 -3.9299486E+09 A3 1.9849426E-17 1.5041072E-18 A4 3.4003576E-04 2.3102794E-04 A5 -2.3250151E-04 -1.7431241E-04 A6 -9.0461876E-06 -6.6054381E-06 A7 1.2903692E-07 9.9484679E-08 A8 7.0585098E-08 6.0013925E-08 A9 7.2746967E-12 -1.2112068E-09 A10 -3.3309218E-10 -3.5633957E-10 A11 -2.1318879E-12 6.3601939E-12 A12 1.0082956E-12 1.3889998E-12 A13 1.0213878E-14 -1.7851551E-14 A14 -1.9661721E-15 -3.4514978E-15 A15 -2.1872468E-17 2.9315592E-17 A16 2.3983563E-18 5.2198028E-18 A17 2.2586872E-20 -2.6618745E-20 A18 -1.6739113E-21 -4.3628823E-21 A19 -9.1342610E-24 1.02991 18E-23 A20 5.1279924E-25 1.5435909E-24

[0266] In Figure 6 are shown the aberration diagrams of the imaging lens of Embodiment 1. In Figure 6 from left to right are shown spherical aberration, astigmatism, distortion aberration, and lateral chromatic aberration. In Figure 6 in the upper part marked with "infinity" are shown the aberration diagrams in the state of focusing on an object at infinity, and in the lower part marked with "0.150 m" are shown the aberration diagrams in the state of focusing on the nearest object. In the spherical aberration diagram, the aberrations under the d-line, C-line, and F-line are represented by solid lines, long dashed lines, and short dashed lines, respectively. In the astigmatism diagram, the aberration under the d-line in the sagittal direction is represented by a solid line, and the aberration under the d-line in the meridional direction is represented by a short dashed line. In the distortion aberration diagram, the aberration under the d-line is represented by a solid line. In the lateral chromatic aberration diagram, the aberrations under the C-line and F-line are represented 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 half field angle is shown after "ω =". The FNo. and ω of the upper diagram correspond to Fno and ωm of the above conditional expressions, respectively.

[0267] Unless otherwise specified, the notations, meanings, recording methods, and illustration methods of the respective data related to the above Embodiment 1 are also basically the same in the following embodiments, and thus the repeated explanations are omitted below. In addition, in the cross-sectional views after Embodiment 2, the illustration of the symbol of the negative partial group G1n is omitted.

[0268] [Embodiment 2]

[0269] A cross-sectional view of the structure of the imaging lens of Embodiment 2 is shown in Figure 7 . The imaging lens of Embodiment 2 includes, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2 having a positive refractive power, and a third lens group G3 having a negative refractive power. The focusing group includes the second lens group G2, and when focusing from an object at infinity to the nearest object, the focusing group moves toward the object side along the optical axis Z.

[0270] The first lens group G1 includes, in order from the object side to the image side, four lenses L11 to L14 and an aperture stop St. The second lens group G2 includes, in order from the object side to the image side, four lenses L21 to L24. The third lens group G3 includes one lens L31.

[0271] Regarding the imaging lens of Embodiment 2, the basic lens data are 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 Tables 8A and 8B, and the respective aberration diagrams are shown in Figure 8 .

[0272] [Table 5]

[0273] Example 2

[0274] Sn R D Nd vd ED Hinf *1 45.3664 1.0000 1.82080 42.71 10.35 3.04 *2 3.6133 1.7951 7.43 3 15.1597 1.9035 1.90525 35.04 7.37 4 -23.1586 0.6649 6.86 *5 -6.5701 1.0000 1.85135 40.10 6.86 *6 -8.6819 0.1002 6.87 7 10.7547 1.8617 1.72916 54.68 6.77 8 -31.5410 1.2500 6.40 9(St) ∞ DD[9] *10 13.6108 1.5528 1.72903 54.04 5.11 *11 -73.3745 0.5478 5.58 (2.07) 12 -15.1811 2.1068 1.43875 94.66 5.80 13 -4.9616 0.9876 1.95906 17.47 6.49 14 -11.0965 0.2113 7.77 *15 -581.7851 1.8287 1.80139 45.45 8.50 *16 -7.4141 DD

[16] 9.08 3.93 / 4.34 *17 -23.2275 1.0021 1.68948 31.02 9.91 *18 78.4493 2.5761 11.07 1.22 19 ∞ 1.3800 1.51680 64.20 20 ∞ 0.4986

[0275] [Table 6]

[0276] Example 2

[0277] f 5.77 Bf 3.98 Fno 1.85 2ωm[°] 108.4

[0278] [Table 7]

[0279] Example 2

[0280] Infinity 0.150m DD[9] 1.3500 1.1819 DD

[16] 1.3863 1.5544

[0281] [Table 8A]

[0282] Example 2

[0283]

[0284] [Table 8B]

[0285] Example 2

[0286] Sn 17 18 KA 6.3728108E-03 3.1535518E-02 A3 -2.1644736E-17 -2.1818904E-18 A4 1.4076404E-04 -5.7220144E-04 A5 -1.5637650E-04 -8.3736308E-05 A6 -4.3455363E-06 4.0783901E-06 A7 -7.8282765E-08 3.2301543E-07 A8 2.9163841E-08 -3.5698069E-08 A9 1.7593700E-10 -1.8676882E-09 A10 -1.1748103E-10 1.8110066E-10 A11 6.0324216E-13 6.6037435E-12 A12 2.8464710E-13 -5.5601696E-13 A13 -3.6593959E-15 -1.4657472E-14 A14 -4.0632110E-16 1.0488751E-15 A15 7.9109228E-18 1.9956322E-17 A16 3.2209656E-19 -1.1876497E-18 A17 -8.3312522E-21 -1.5215860E-20 A18 -1.2487554E-22 7.3948022E-22 A19 3.5423609E-24 4.9727690E-24 A20 1.8097025E-26 -1.9394570E-25

[0287] [Example 3]

[0288] The cross-sectional view of the structure of the imaging lens of Example 3 is shown in Figure 9 . The imaging lens of Example 3 includes, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2 having a positive refractive power, and a third lens group G3 having a negative refractive power. The focusing group includes the second lens group G2, and when focusing from an infinitely distant object to the nearest object, the focusing group moves toward the object side along the optical axis Z.

[0289] The first lens group G1 includes, in order from the object side to the image side, four lenses L11 to L14 and an aperture stop St. The second lens group G2 includes, in order from the object side to the image side, four lenses L21 to L24. The third lens group G3 includes one lens L31.

[0290] Regarding the imaging lens of Example 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 Tables 12A and 12B, and the respective aberration diagrams are shown in Figure 10 .

[0291] [Table 9]

[0292] Example 3

[0293] Sn R D Nd v d ED Hinf *1 173.7926 0.9998 1.63858 55.18 12.89 3.28 / 6.40 *2 3.9375 2.2849 8.78 3 15.1597 2.1929 1.78800 47.37 8.72 4 -26.0468 0.9561 8.07 *5 -6.5537 1.0000 1.85135 40.10 8.07 *6 -8.4462 0.1000 8.16 7 12.1615 1.6966 1.72916 54.68 7.14 8 -59.8205 1.2501 6.48 9(St) ∞ DD[9] *10 12.2614 1.6094 1.80139 45.45 4.81 *11 -34.9421 0.7352 4.43 (1.64) 12 -10.1013 1.4584 1.43875 94.66 4.85 13 -5.0976 0.8557 1.95906 17.47 5.55 14 -10.7407 0.6314 6.58 *15 7640.2230 1.8932 1.80139 45.45 8.15 4.06 *16 -7.0261 DD

[16] 8.50 2.5 *17 -11.8782 1.0002 1.68948 31.02 8.86 *18 235.5632 1.8451 10.55 0.74 19 ∞ 1.3800 1.51680 64.20 20 ∞ 0.4987

[0294] [Table 10]

[0295] Example 3

[0296] f 5.77 Bf 3.25 Fno 1.85 2ωm[°] 108.4

[0297] [Table 11]

[0298] Example 3

[0299] Infinity 0.150m DD[9] 1.3496 1.2017 DD

[16] 1.3141 1.4620

[0300] [Table 12A]

[0301] Example 3

[0302]

[0303] [Table 12B]

[0304] Example 3

[0305] Sn 17 18 KA 1.5835245E+00 -1.1961173E+03 A3 -2.8138665E-17 3.1483428E-19 A4 -1.9598514E-04 -4.8812257E-04 A5 -2.4367278E-04 -1.3006315E-04 A6 -1.4942924E-06 2.8486701E-06 A7 1.9199498E-07 3.7835262E-07 A8 5.1820791E-09 -2.5352898E-08 A9 -3.4992345E-10 -1.8627184E-09 A10 5.9986128E-12 1.2237767E-10 A11 -4.3156049E-13 6.1575984E-12 A12 -1.0676495E-13 -3.3512351E-13 A13 4.4703534E-15 -1.3461249E-14 A14 3.5879640E-16 5.1689990E-16 A15 -1.0302487E-17 1.8642483E-17 A16 -5.6973845E-19 -4.0697095E-19 A17 1.0432738E-20 -1.4763108E-20 A18 4.3757088E-22 1.0698165E-22 A19 -4.0055319E-24 5.0678481E-24 A20 -1.2721628E-25 2.2636151E-26

[0306] [Example 4]

[0307] A cross-sectional view of the structure of the imaging lens of Example 4 is shown in Figure 11 . The imaging lens of Example 4 includes, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens group G3 having a positive refractive power. The focusing group includes the second lens group G2, and when focusing from an infinite object to the nearest object, the focusing group moves toward the image side along the optical axis Z.

[0308] The first lens group G1 includes, in order from the object side to the image side, lenses L11 to L14, an aperture stop St, and a lens L15. The second lens group G2 includes, in order from the object side to the image side, two lenses L21 to L22. The third lens group G3 includes, in order from the object side to the image side, two lenses L31 to L32.

[0309] Regarding the imaging lens of Example 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 Tables 16A and 16B, and the aberration diagrams are shown in Figure 12 .

[0310] [Table 13]

[0311] Example 4

[0312] Sn R D Nd v d ED Hinf *1 800.5141 0.9999 1.68948 31.02 10.49 3.49 *2 4.3750 2.2171 7.36 3 15.1597 1.6271 2.00100 29.14 7.10 4 -29.2961 0.7710 6.63 *5 -5.8832 1.0041 1.85135 40.10 6.37 *6 -7.8121 0.1002 6.20 7 14.6679 0.9055 1.71299 53.87 5.95 8 -46.0676 1.2498 5.78 9(St) ∞ 1.3587 *10 11.7126 1.1997 1.80610 40.73 4.74 *11 -19.5325 DD

[11] 5.04 (2.41) 12 -9.4671 1.2452 1.43875 94.66 5.59 13 -4.5676 0.8672 1.95906 17.47 5.90 14 -14.1064 DD

[14] 7.12 *15 -2289.6291 1.6846 1.80139 45.45 8.23 0.12 / 0.87 / 1.36 / 3.86 *16 -5.9627 0.6371 8.56 2.48 / 4.14 *17 -13.9696 1.0684 1.68948 31.02 8.65 *18 75.9007 2.1102 10.30 0.98 19 ∞ 1.3800 1.51680 64.20 20 ∞ 0.4979

[0313] [Table 14]

[0314] Example 4

[0315] f 5.92 Bf 3.52 Fno 1.85 2ωm[°] 106.6

[0316] [Table 15]

[0317] Example 4

[0318] Infinity 0.150m DD

[11] 1.1198 1.3515 DD

[14] 0.5232 0.2915

[0319] [Table 16A]

[0320] Example 4

[0321]

[0322] [Table 16B]

[0323] Example 4

[0324] Sn 17 18 KA -3.8147494E-01 -1.0122843E+03 A3 -1.0779889E-17 1.1145026E-17 A4 -3.9288244E-04 -6.5891726E-04 A5 -3.1448644E-04 -1.6299693E-04 A6 2.2377689E-06 2.9357493E-06 A7 6.3829461E-07 8.2612182E-08 A8 -2.6426988E-08 -2.2789229E-08 A9 -2.0431514E-09 -1.3966774E-09 A10 1.8729839E-10 1.1068490E-10 A11 4.0722930E-12 7.0390940E-12 A12 -7.5953864E-13 -3.1666748E-13 A13 -2.3147484E-15 -1.8544299E-14 A14 1.8259512E-15 5.3741077E-16 A15 -5.8151374E-18 2.7995348E-17 A16 -2.5731968E-18 -5.2290301E-19 A17 1.0819497E-20 -2.2824231E-20 A18 1.9599759E-21 2.6006965E-22 A19 -5.3870907E-24 7.7728473E-24 A20 -6.2188699E-25 -4.6620024E-26

[0325] [Example 5]

[0326] A cross-sectional view of the structure of the imaging lens of Example 5 is shown in Figure 13 . The imaging lens of Example 5 includes, in order from the object side to the image side, a first lens group G1 having positive refractive power, a second lens group G2 having positive refractive power, and a third lens group G3 having negative refractive power. The focusing group includes the second lens group G2, and when focusing from an infinitely distant object to the nearest object, the focusing group moves toward the object side along the optical axis Z.

[0327] The first lens group G1 includes, in order from the object side to the image side, four lenses L11 to L14 and an aperture stop St. The second lens group G2 includes, in order from the object side to the image side, four lenses L21 to L24. The third lens group G3 includes one lens L31.

[0328] 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 Tables 20A and 20B, and the various aberration diagrams are shown in Figure 14 .

[0329] [Table 17]

[0330] Example 5

[0331] Sn R D Nd v d ED Hinf *1 -146.8622 1.0002 1.68948 31.02 8.75 0.46 / 3.01 *2 4.5968 1.1194 6.28 3 15.1597 1.4298 1.85025 30.05 6.23 4 -16.6799 0.4063 5.75 *5 -5.4255 1.0000 1.85135 40.10 5.75 *6 -7.7247 0.1000 5.41 7 14.2926 1.0889 1.67790 55.35 5.19 8 -91.4454 1.2500 4.92 9(St) ∞ DD[9] *10 9.0119 1.4698 1.80139 45.45 5.32 *11 -11.9230 1.2363 5.51 12 -6.9074 0.7600 1.43875 94.66 5.66 13 -7.0998 0.7500 1.95906 17.47 5.93 14 45.3925 0.1002 6.74 *15 -833.1180 1.5441 1.80139 45.45 6.95 0.13 / 0.74 / 1.06 / 3.08 *16 -4.5673 DD

[16] 7.40 2.00 / 3.44 *17 -11.0540 1.0000 1.68948 31.02 8.48 *18 -1954.8569 1.4973 10.20 0.27 / 1.56 19 ∞ 1.3800 1.51680 64.20 20 ∞ 0.4987

[0332] [Table 18]

[0333] Example 5

[0334] f 5.85 Bf 2.91 Fno 1.85 2ωm[°] 108.0

[0335] [Table 19]

[0336] Example 5

[0337] Infinity 0.150m DD[9] 1.3500 1.1983 DD

[16] 1.1693 1.3210

[0338] [Table 20A]

[0339] Example 5

[0340]

[0341] [Table 20B]

[0342] Example 5

[0343] Sn 17 18 KA 1.8066090E+00 1.1856862E+05 A3 4.8601285E-17 -2.2354720E-18 A4 2.4522907E-03 7.3369158E-04 A5 -3.7309132E-04 -2.4863881E-04 A6 -6.1757644E-05 -9.2507153E-06 A7 -1.6424056E-06 -1.1382405E-06 A8 5.2123060E-07 8.3365587E-08 A9 1.1488948E-08 6.6516306E-09 A10 -2.8195026E-09 -4.5714945E-10 A11 -3.7174958E-11 -2.3590630E-11 A12 1.0018391E-11 1.6998262E-12 A13 7.2068195E-14 5.7442057E-14 A14 -2.2937815E-14 -4.3450287E-15 A15 -8.6134238E-17 -8.9256017E-17 A16 3.2597140E-17 7.1093037E-18 A17 6.1406900E-20 7.9102853E-20 A18 -2.6228756E-20 -6.5459765E-21 A19 -2.2593500E-23 -3.0664329E-23 A20 9.1512481E-24 2.5465916E-24

[0344] [Example 6]

[0345] A cross-sectional view of the structure of the imaging lens of Example 6 is shown in Figure 15 . The imaging lens of Example 6 includes, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens group G3 having a positive refractive power. The focusing group includes the second lens group G2, and when focusing from an infinitely distant object to the nearest object, the focusing group moves toward the image side along the optical axis Z.

[0346] The first lens group G1 includes, in order from the object side to the image side, lenses L11 to L13, an aperture stop St, and lenses L14 to L16. The second lens group G2 includes one lens L21. The third lens group G3 includes two lenses L31 to L32 in order from the object side to the image side.

[0347] 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 various aberration diagrams are shown in Figure 16 .

[0348] [Table 21]

[0349] Example 6

[0350] Sn R D Nd v d ED Hinf *1 87.8058 0.8228 1.80610 40.73 12.89 6.32 *2 7.1602 2.5132 9.66 3 14.8588 0.7995 1.49700 81.54 8.91 4 9.5326 0.9999 8.07 5 13.9634 1.5799 2.00100 29.14 7.57 6 729.6407 1.7001 6.85 7(St) ∞ 1.9002 *8 -176.6681 1.0468 1.49710 81.56 5.36 *9 -46.5605 0.3921 5.83 (1.9) 10 57.0732 3.9590 1.72916 54.68 6.22 11 -5.5685 0.5998 1.89286 20.36 7.74 12 -7.5253 DD

[12] 8.45 *13 -10.9538 0.7002 1.82115 24.06 9.43 (3.88) *14 -29.1293 DD

[14] 10.00 3.49 *15 -66.6355 1.2217 1.85070 26.91 11.88 *16 465.7698 0.0998 14.70 0.30 / 2.34 / 2.92 17 62.5324 2.6849 1.89190 37.13 17.91 18 -37.1835 5.1644 18.45 19 ∞ 1.3800 1.51680 64.20 20 ∞ 1.0017

[0351] [Table 22]

[0352] Example 6

[0353] f 9.74 Bf 7.08 Fno 3.60 2ωm[°] 108.2

[0354] [Table 23]

[0355] Example 6

[0356] Infinity 0.266m DD

[12] 2.3454 2.6239 DD

[14] 3.5867 3.3082

[0357] [Table 24]

[0358] Example 6

[0359]

[0360] [Example 7]

[0361] A cross-sectional view of the structure of the imaging lens of Example 7 is shown in Figure 17 . The imaging lens of Example 7 includes, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens group G3 having a positive refractive power. The focusing group includes the second lens group G2, and when focusing from an infinitely distant object to the nearest object, the focusing group moves toward the image side along the optical axis Z.

[0362] The first lens group G1 includes, in order from the object side to the image side, lenses L11 to L13, an aperture stop St, and lenses L14 to L15. The second lens group G2 includes one lens L21. The third lens group G3 includes two lenses L31 to L32 in order from the object side to the image side.

[0363] Regarding the imaging lens of Example 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 various aberration diagrams are shown in Figure 18 .

[0364] [Table 25]

[0365] Example 7

[0366] Sn R D Nd [[ID=2 ​ ​ *1 109.3318 0.6951 1.80139 45.45 12.56 5.49 *2 7.2798 2.4665 9.70 3 16.4934 0.7043 1.43700 95.10 9.02 4 8.8742 1.0002 8.20 5 14.3607 2.3790 2.00100 29.14 7.85 6 -143.7028 1.6998 6.77 ​ ∞ 2.2099 8 27.7556 3.5318 1.69680 55.53 6.19 9 -5.4575 0.6001 1.89286 20.36 7.40 10 -8.5103 ​ 8.15 *11 -9.5998 0.7000 1.82115 24.06 9.35 *12 -24.0062 ​ 10.24 *13 1305.2862 1.0095 1.76802 49.24 12.26 0.17 *14 -81.2177 0.0998 14.42 15 59.7346 2.9378 1.90525 35.04 17.57 16 -40.2682 6.2018 18.29 17 ∞ 1.3800 1.51680 64.20 18 ∞ 1.0016

[0367] [Table 26]

[0368] Example 7

[0369] f 9.78 ​ 8.11 ​ 3.60 ​ 108.0

[0370] [Table 27]

[0371] Example 7

[0372] ​ 0.265m ​ 2.7164 3.0531 ​ 3.2735 2.9368

[0373] [Table 28]

[0374] Example 7

[0375]

[0376] [Example 8]

[0377] A cross-sectional view of the structure of the imaging lens of Example 8 is shown in ​ . The imaging lens of Example 8 includes, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens group G3 having a positive refractive power. The focusing group includes the second lens group G2, and when focusing from an infinitely distant object to the nearest object, the focusing group moves toward the image side along the optical axis Z.

[0378] The first lens group G1 includes, in order from the object side to the image side, lenses L11 to L13, an aperture stop St, and lenses L14 to L15. The second lens group G2 includes one lens L21. The third lens group G3 includes three lenses L31 to L33 in order from the object side to the image side.

[0379] Regarding the imaging lens of Example 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 ​ .

[0380] [Table 29]

[0381] Example 8

[0382] ​ R D ​ ​ ​ ​ *1 68.4725 0.8503 1.80139 45.45 12.71 6.21 *2 7.3409 2.5621 9.59 3 14.1170 0.6926 1.43700 95.10 8.68 4 7.8077 1.0265 7.76 5 15.8089 2.1440 2.00100 29.13 7.42 6 -89.2226 1.7965 6.40 ​ ∞ 2.4059 8 26.0904 3.0001 1.61800 63.32 6.09 9 -5.1453 0.6284 1.89286 20.36 7.01 10 -7.3869 ​ 7.78 *11 -9.3226 0.6998 1.68948 31.02 9.44 *12 -21.2092 ​ 10.38 (4.34) *13 -457.0655 0.9999 1.69350 53.20 12.40 *14 -55.2246 0.1378 14.07 15 263.4030 3.2321 1.80440 39.58 15.88 16 -20.5808 0.8611 16.98 *17 -20.5291 0.9501 1.68948 31.02 17.78 4.98 *18 -58.3808 5.1359 18.58 5.57 19 ∞ 1.3800 1.51680 64.20 20 ∞ 1.0007

[0383] [Table 30]

[0384] Example 8

[0385] f 10.31 ​ 7.05 ​ 3.60 ​ 108.0

[0386] [Table 31]

[0387] Example 8

[0388] ​ 0.265m ​ 2.8152 3.2155 ​ 2.6763 2.2760

[0389] [Table 32]

[0390] Example 8

[0391]

[0392] [Example 9]

[0393] A cross-sectional view of the structure of the imaging lens of Example 9 is shown in ​ . The imaging lens of Example 9 includes, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens group G3 having a positive refractive power. The focusing group includes the second lens group G2, and when focusing from an infinitely distant object to the nearest object, the focusing group moves toward the image side along the optical axis Z.

[0394] The first lens group G1 includes lenses L11 to L13, an aperture stop St, and lenses L14 to L15 in order from the object side to the image side. The second lens group G2 includes a single lens L21. The third lens group G3 includes three lenses L31 to L33 in order from the object side to the image side.

[0395] 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 each aberration diagram is shown in ​ it.

[0396] [Table 33]

[0397] Example 9

[0398] ​ R D ​ ​ ​ ​ *1 89.0215 0.8500 1.80139 45.45 12.77 6.21 *2 7.0929 3.4672 9.54 3 12.7532 0.6002 1.43700 95.10 8.03 4 8.7861 0.4766 7.40 5 16.6724 2.3796 2.00100 29.13 7.35 6 -59.1216 1.6998 6.20 ​ ∞ 2.2093 8 26.1122 2.9361 1.61800 63.32 6.20 9 -4.8962 0.5998 1.89286 20.36 7.04 10 -7.0137 ​ 7.81 *11 -8.1164 0.6998 1.68948 31.02 9.00 *12 -23.9890 ​ 9.93 (3.08) *13 -256.9881 0.9996 1.69350 53.20 12.13 *14 -31.0413 0.2498 13.99 15 -960.7652 3.7187 1.80440 39.58 16.09 16 -17.1516 0.7835 17.39 *17 -16.6908 0.9499 1.68948 31.02 17.86 *18 -62.8379 4.8807 19.14 19 ∞ 1.3800 1.51680 64.20 20 ∞ 1.0007

[0399] [Table 34]

[0400] Example 9

[0401] f 10.31 ​ 6.79 ​ 3.60 ​ 108.0

[0402] [Table 35]

[0403] Example 9

[0404] ​ 0.265m ​ 2.3127 2.5942 ​ 2.8101 2.5286

[0405] [Table 36]

[0406] Example 9

[0407]

[0408] [Example 10]

[0409] A cross-sectional view of the structure of the imaging lens of Example 10 is shown in ​ it. The imaging lens of Example 10 includes a first lens group G1 having a positive refractive power, a second lens group G2 having a positive refractive power, and a third lens group G3 having a positive refractive power in order from the object side to the image side. The focusing group includes the second lens group G2, and when focusing from an infinite object to the nearest object, the focusing group moves toward the object side along the optical axis Z.

[0410] The first lens group G1 includes lenses L11 to L13, an aperture stop St, and lenses L14 to L17 in order from the object side to the image side. The second lens group G2 includes a single lens L21. The third lens group G3 includes two lenses L31 to L32 in order from the object side to the image side.

[0411] Regarding the imaging lens of Example 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 Tables 40A and 40B, and each aberration diagram is shown in ​ .

[0412] [Table 37]

[0413] Example 10

[0414] ​ R D ​ ​ ​ ​ *1 29.6565 0.8502 1.80139 45.45 13.68 6.21 *2 7.3376 2.9840 10.40 3 18.8507 0.6002 1.43700 95.10 9.51 4 7.9965 0.9581 8.49 5 21.0617 1.8369 2.00100 29.13 8.38 6 -49.9489 1.7002 7.70 ​ ∞ 2.1126 *8 27.5825 1.3250 1.80139 45.45 5.80 *9 -37.7610 0.2103 6.37 10 219.9200 0.6002 1.84666 23.78 6.71 11 12.1690 2.7387 1.72916 54.68 7.24 12 -10.6403 0.7555 8.01 *13 -7.7274 0.7002 1.68948 31.02 8.18 *14 -21.0051 ​ 9.17 (3.75) 15 -23.7799 1.7703 1.77250 49.60 11.13 16 -12.5430 ​ 11.88 *17 -36.8454 1.6451 1.69350 53.18 12.98 6.44 *18 -13.2871 1.1206 14.54 5.57 *19 -9.2284 1.4664 1.68948 31.02 16.32 5.09 *20 -16.1057 4.3367 1716 8.08 / 8.59 21 ∞ 1.3800 1.51680 64.20 22 ∞ 0.9994

[0415] [Table 38]

[0416] Example 10

[0417] f 10.31 ​ 6.25 ​ 2.88 ​ 108.0

[0418] [Table 39]

[0419] Example 10

[0420] ​ 0.265m ​ 2.1729 1.4703 ​ 2.7515 3.4541

[0421] [Table 40A]

[0422] Example 10

[0423]

[0424] [Table 40B]

[0425] Example 10

[0426] ​ 19 20 ​ 0.0000000E+00 0.0000000E+00 A3 -2.2204460E-18 9.2370556E-18 A4 -1.0556496E-03 -7.5331920E-04 A5 7.5999417E-05 3.0610664E-04 A6 2.6945557E-05 -3.1660585E-05 A7 -7.2747374E-07 -4.1743278E-06 A8 -2.9073699E-07 7.1278687E-07 A9 3.3387539E-09 2.4707055E-08 A10 1.7559954E-09 -5.8503490E-09 A11 -9.6730603E-12 -9.1273904E-11 A12 -6.3964018E-12 2.5164298E-11 A13 1.7161004E-14 2.1096534E-13 A14 1.4374005E-14 -6.2413282E-14 A15 -1.7548020E-17 -2.9595982E-16 A16 -1.9503917E-17 8.9953256E-17 A17 8.9943715E-21 2.2972735E-19 A18 1.4655293E-20 -7.0107179E-20 A19 -1.5525408E-24 -7.5603160E-23 A20 -4.6833486E-24 2.2880676E-23

[0427] [Example 11]

[0428] A cross-sectional view of the structure of the imaging lens of Example 11 is shown in ​ . The imaging lens of Example 11 includes, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2 having a positive refractive power, and a third lens group G3 having a negative refractive power. The focusing group includes the second lens group G2, and when focusing from an infinitely distant object to the nearest object, the focusing group moves toward the object side along the optical axis Z.

[0429] The first lens group G1 includes, in order from the object side to the image side, lenses L11 to L13, an aperture stop St, and lenses L14 to L17. The second lens group G2 includes one lens L21. The third lens group G3 includes two lenses L31 to L32 in order from the object side to the image side.

[0430] 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 Tables 44A and 44B, and each aberration diagram is shown in ​ .

[0431] [Table 41]

[0432] Example 11

[0433] ​ R D ​ ​ ​ ​ *1 29.1308 0.8500 1.80139 45.45 13.18 6.06 *2 7.2822 3.4215 9.96 3 58.4772 0.6003 1.43700 95.10 8.98 4 11.0518 0.4269 8.09 5 22.9324 1.8341 2.00100 29.13 8.08 6 -41.7970 1.7002 7.37 ​ ∞ 2.0002 *8 22.4642 1.0002 1.80139 45.45 5.80 *9 -26.5808 0.2103 6.13 10 -32.6994 0.6001 1.84666 23.78 6.30 11 22.2167 2.2381 1.72916 54.68 6.83 12 -10.3916 0.8246 7.57 *13 -6.8766 0.7000 1.68948 31.02 7.78 *14 -21.8538 ​ 8.97 (2.35) 15 -42.8678 2.1870 1.69680 55.53 11.07 16 -9.9194 ​ 11.65 *17 -28.7134 1.3178 1.69350 53.18 13.37 6.63 *18 -13.3604 1.1204 14.74 5.68 *19 -9.1035 1.4998 1.68948 31.02 16.63 4.96 *20 -16.3421 4.4562 17.95 7.23 21 ∞ 1.3800 1.51680 64.20 22 ∞ 1.0000

[0434] [Table 42]

[0435] Example 11

[0436] f 10.31 ​ 6.37 ​ 2.88 ​ 108.0

[0437] [Table 43]

[0438] Example 11

[0439] ​ 0.265m ​ 1.6240 1.2235 ​ 4.0184 4.4189

[0440] [Table 44A]

[0441] Example 11

[0442]

[0443]

[0444] [Table 44B]

[0445] Example 11

[0446] ​ 19 20 ​ 0.0000000E+00 0.0000000E+00 A3 1.0658141E-18 7.8159701E-18 A4 -1.0360019E-03 -8.0440995E-04 A5 1.1304146E-04 3.1753494E-04 A6 2.2381801E-05 -3.1205350E-05 A7 -1.0567613E-06 -4.2750041E-06 A8 -2.3967155E-07 7.1648145E-07 A9 5.3354050E-09 2.5262539E-08 A10 1.4382046E-09 -5.9090841E-09 A11 -1.7301240E-11 -9.3142180E-11 A12 -5.2155611E-12 2.5483109E-11 A13 3.5324349E-14 2.1494250E-13 A14 1.1686031E-14 -6.3328197E-14 A15 -4.3661735E-17 -3.0122751E-16 A16 -1.5828467E-17 9.1430553E-17 A17 2.9715782E-20 2.3371256E-19 A18 1.1884307E-20 -7.1376451E-20 A19 -8.5158233E-24 -7.6919899E-23 A20 -3.7984952E-24 2.3332902E-23

[0447] [Example 12]

[0448] A cross-sectional view of the structure of the imaging lens of Example 12 is shown in ​ . The imaging lens of Example 12 includes, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2 having a positive refractive power, and a third lens group G3 having a negative refractive power. The focusing group includes the second lens group G2, and when focusing from an infinite object to the nearest object, the focusing group moves toward the object side along the optical axis Z.

[0449] The first lens group G1 includes, in order from the object side to the image side, four lenses L11 to L14 and an aperture stop St. The second lens group G2 includes, in order from the object side to the image side, three lenses L21 to L23. The third lens group G3 includes one lens L31.

[0450] 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 Tables 48A and 48B, and the aberration diagrams are shown in ​ .

[0451] [Table 45]

[0452] Example 12

[0453] ​ R D ​ ​ ​ ​ *1 -130.9793 1.0000 1.80139 45.45 8.14 0.56 / 3.09 *2 4.8573 0.8969 6.00 3 15.1597 1.5694 1.95375 32.32 5.94 4 -14.5402 0.3579 5.38 *5 -5.4050 1.0000 2.00178 19.32 5.38 *6 -9.8761 0.1000 5.12 7 18.0211 1.2771 1.90525 35.04 5.04 8 -19.4648 1.2504 4.98 ​ ∞ ​ *10 9.3393 1.9888 1.85135 40.10 5.48 *11 -11.0363 1.0406 5.63 12 -6.3516 0.8072 1.92286 18.90 5.65 13 18.3414 0.1119 6.52 *14 -4796.8892 1.8204 1.73077 40.51 6.60 0.06 / 2.91 *15 -4.4313 ​ 7.32 1.92 / 3.36 *16 -13.9199 1.0661 1.49710 81.56 8.53 *17 343.8363 1.5916 10.15 1.58 18 ∞ 1.3800 1.51680 64.20 19 ∞ 0.4998

[0454] [Table 46]

[0455] Example 12

[0456] f 5.87 ​ 3.00 ​ 1.85 ​ 108.0

[0457] [Table 47]

[0458] Example 12

[0459] ​ 0.150m ​ 1.3500 1.1719 ​ 0.9844 1.1625

[0460] [Table 48A]

[0461] Example 12

[0462]

[0463] [Table 48B]

[0464] Example 12

[0465] Sn 16 17 KA -2.4968528E-01 -1.3034168E+08 A3 -7.2095152E-18 -4.0155241E-17 A4 2.1750805E-03 2.2610519E-04 A5 -4.0283096E-04 -3.3914331E-05 A6 -4.1485491E-05 -1.0467895E-05 A7 -1.1913075E-06 -5.7101015E-06 A8 3.0946128E-07 8.7047966E-08 A9 7.1700391E-09 3.8671746E-08 A10 -1.6404603E-09 -3.6384658E-10 A11 -1.5649543E-11 -1.5862008E-10 A12 5.8397411E-12 9.5043783E-13 A13 1.1406791E-14 4.1243205E-13 A14 -1.3113898E-14 -1.8999252E-15 A15 1.4943531E-17 -6.5720707E-16 A16 1.7706131E-17 3.0476256E-18 A17 -3.3084098E-20 5.8487155E-19 A18 -1.3093693E-20 -3.2083646E-21 A19 1.6135785E-23 -2.2309479E-22 A20 4.0607506E-24 1.5026543E-24

[0466] [Example 13]

[0467] A cross-sectional view of the structure of the imaging lens of Example 13 is shown in Figure 29 . The imaging lens of Example 13 includes, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2 having a positive refractive power, and a third lens group G3 having a negative refractive power. The focusing group includes the second lens group G2, and when focusing from an infinitely distant object to the nearest object, the focusing group moves toward the object side along the optical axis Z.

[0468] The first lens group G1 includes, in order from the object side to the image side, three lenses L11 to L13 and an aperture stop St. The second lens group G2 includes, in order from the object side to the image side, three lenses L21 to L23. The third lens group G3 includes one lens L31.

[0469] 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 Tables 52A and 52B, and each aberration diagram is shown in Figure 30 .

[0470] [Table 49]

[0471] Example 13

[0472] Sn R D Nd v d ED Hinf *1 -48.8594 1.0002 1.55332 71.68 6.23 0 / 3.07 *2 5.7237 1.1832 4.13 *3 -4.5681 1.0553 2.00178 19.32 4.10 *4 -5.8911 0.1212 4.01 *5 18.2743 1.4108 1.77250 49.50 4.14 *6 -6.5126 0.8200 4.15 7(St) ∞ DD[ *8 10.6105 1.6105 1.72903 54.04 4.91 *9 -10.5678 0.3004 5.11 *10 -5.3468 0.7502 1.82115 24.06 5.00 *11 1006.7591 0.1960 5.42 *12 23.8229 1.1928 1.53116 56.04 5.42 1.20 / 2.12 *13 -3.1860 ​ 6.14 1.46 / 2.60 *14 -6.4493 1.0001 1.68893 31.16 7.51 *15 9.8738 0.3675 9.42 16 ∞ 1.3800 1.51680 64.20 17 ∞ 0.2997

[0473] [Table 50]

[0474] Example 13

[0475] f 5.18 ​ 1.58 ​ 1.85 ​ 108.0

[0476] [Table 51]

[0477] Example 13

[0478] ​ 0.150m ​ 0.8202 0.7111 ​ 1.6615 1.7706

[0479] [Table 52A]

[0480] Example 13

[0481]

[0482] [Table 52B]

[0483] Example 13

[0484]

[0485] [Example 14]

[0486] A cross-sectional view of the structure of the imaging lens of Example 14 is shown in ​ . The imaging lens of Example 14 includes, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2 having a positive refractive power, and a third lens group G3 having a negative refractive power. The focusing group includes the second lens group G2, and when focusing from an infinite object to the nearest object, the focusing group moves toward the object side along the optical axis Z.

[0487] The first lens group G1 includes, in order from the object side to the image side, two lenses L11 to L12 and an aperture stop St. The second lens group G2 includes, in order from the object side to the image side, three lenses L21 to L23. The third lens group G3 includes one lens L31.

[0488] 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 Tables 56A and 56B, and each aberration diagram is shown in ​ .

[0489] [Table 53]

[0490] Example 14

[0491] ​ R D ​ ​ ​ ​ *1 -4.5596 0.7499 2.00178 19.32 4.35 *2 -6.5277 0.1001 4.03 1.80 *3 7.0787 1.2698 1.85135 40.10 3.77 1.40 *4 -9.9356 0.5004 3.44 ​ ∞ ​ *6 10.5463 1.0584 1.71300 53.94 2.72 (1.25) *7 -9.3369 0.3729 3.28 *8 -2.4312 0.7498 2.00178 19.32 3.34 *9 -3.5906 0.1002 3.96 *10 -2438.6672 0.8670 1.95150 29.83 4.04 0.05 / 0.12 *11 -3.2765 ​ 4.68 *12 -2.6841 0.7501 2.00178 19.32 5.02 *13 76.4206 0.1481 7.55 0.55 14 ∞ 1.3800 1.51680 64.20 15 ∞ 0.1502

[0492] [Table 54]

[0493] Example 14

[0494] f 4.69 ​ 1.21 ​ 1.85 ​ 108.0

[0495] [Table 55]

[0496] Example 14

[0497] ​ 0.150m ​ 0.5004 0.4287 ​ 0.5026 0.5743

[0498] [Table 56A]

[0499] Example 14

[0500]

[0501] [Table 56B]

[0502] Example 14

[0503] ​ 10 11 12 13 ​ -1.8599746E-01 -4.8435044E-03 -9.1063105E-03 -9.2496285E+03 A3 0.0000000E+00 -4.9323248E-17 -5.6288272E-17 -9.4620709E-18 A4 2.6801380E-02 4.1456689E-02 4.2912965E-03 -1.5744034E-03 A5 -1.5158025E-01 -9.2455675E-02 -2.4295038E-03 -6.5629293E-04 A6 1.4801765E-01 5.6891966E-02 -5.2291528E-05 6.7175201E-05 A7 7.1387520E-03 1.8093757E-02 -8.6262801E-06 3.3750281E-06 A8 -8.1667621E-02 -2.8201612E-02 2.6934413E-07 -5.1458805E-07 A9 1.7844678E-02 -8.5593159E-06 5.7755346E-08 -2.2203467E-08 A10 2.1059107E-02 6.0446971E-03 -6.3091985E-10 2.4070056E-09 A11 -6.3735697E-03 -3.7392428E-04 -6.2876542E-11 1.0083557E-10 A12 -3.1234120E-03 -7.2582815E-04 -3.3441986E-13 -8.0559340E-12 A13 9.8993678E-04 4.8029365E-05 -3.3343916E-13 -2.8196227E-13 A14 2.7816926E-04 5.1827593E-05 6.8253289E-15 1.9270925E-14 A15 -8.0390968E-05 -2.7236230E-06 1.1160052E-15 4.8136870E-16 A16 -1.4580633E-05 -2.1817048E-06 -1.8376455E-17 -3.0448353E-17 A17 3.3375770E-06 7.4761306E-08 -1.1320123E-18 -4.6101283E-19 A18 4.1109400E-07 4.9964783E-08 2.0446764E-20 2.7580079E-20 A19 -5.5998984E-08 -8.0850525E-10 2.5571634E-22 1.8895710E-22 A20 -4.755471 3E-09 -4.7988726E-10 -7.9157127E-24 -1.0567432E-23

[0504] [Example 15]

[0505] A cross-sectional view of the structure of the imaging lens of Example 15 is shown in ​ . The imaging lens of Example 15 includes, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2 having a positive refractive power, and a third lens group G3 having a negative refractive power. The focusing group includes the second lens group G2, and when focusing from an infinite object to the nearest object, the focusing group moves toward the object side along the optical axis Z.

[0506] The first lens group G1 includes, in order from the object side to the image side, two lenses L11 to L12 and an aperture stop St. The second lens group G2 includes, in order from the object side to the image side, two lenses L21 to L22. The third lens group G3 includes one lens L31.

[0507] 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 Tables 60A and 60B, and each aberration diagram is shown in ​ .

[0508] [Table 57]

[0509] Example 15

[0510] ​ R D ​ ​ ​ ​ *1 -4.1766 0.5864 1.63350 23.62 3.67 1.33 / 1.65 *2 -7.6334 0.0998 3.02 0.85 / 1.46 *3 4.3031 0.8564 1.80139 45.45 2.77 0.91 *4 -248.7443 0.3002 2.47 ​ ∞ ​ *6 6.9551 0.7529 1.55332 71.68 2.00 *7 -13.8733 0.5180 2.52 *8 -8.4052 0.7602 1.95150 29.83 2.78 *9 -1.7942 ​ 3.31 1.63 *10 -1.7974 0.6032 1.63350 23.62 3.63 *11 5.0005 0.4000 5.87 1.10 12 ∞ 1.3800 1.51680 64.20 13 ∞ 0.2339

[0511] [Table 58]

[0512] Example 15

[0513] f 3.83 ​ 1.54 ​ 1.85 ​ 107.8

[0514] [Table 59]

[0515] Example 15

[0516] ​ 0.150m ​ 0.2998 0.2708 ​ 0.2140 0.2430

[0517] [Table 60A]

[0518] Example 15

[0519]

[0520] [Table 60B]

[0521] Example 15

[0522] ​ 10 11 ​ 0.0000000E+00 0.0000000E+00 A3 -1.1417586E-17 -4.1018936E-18 A4 2.3721154E-02 -2.2981734E-02 A5 -5.0273465E-03 4.9855913E-03 A6 -6.3010079E-04 1.9000021E-04 A7 -4.2381067E-04 -1.2454970E-04 A8 7.6442438E-06 -1.5821344E-06 A9 4.4378992E-06 1.4327846E-06 A10 4.3345373E-09 9.6931255E-09 A11 -3.6054599E-08 -1.0176480E-08 A12 -1.0152700E-09 -3.6797377E-11 A13 2.1614011E-10 4.5030625E-11 A14 1.0859283E-11 6.9054214E-14 A15 -8.6571102E-13 -1.2119825E-13 A16 -5.3310451E-14 5.6364589E-19 A17 2.0315305E-15 1.8240909E-16 A18 1.2919331E-16 -2.3828082E-19 A19 -2.0800336E-18 -1.1831835E-19 A20 -1.2496291E-19 3.0516916E-22

[0523] [Example 16]

[0524] A cross-sectional view of the structure of the imaging lens of Example 16 is shown in ​ . The imaging lens of Example 16 includes, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, and a third lens group G3 having a negative refractive power. The focusing group includes the second lens group G2, and when focusing from an infinitely distant object to the nearest object, the focusing group moves toward the image side along the optical axis Z.

[0525] The first lens group G1 includes, in order from the object side to the image side, lenses L11 to L14, an aperture stop St, and a lens L15. The second lens group G2 includes, in order from the object side to the image side, two lenses L21 and L22. The third lens group G3 includes, in order from the object side to the image side, two lenses L31 and L32.

[0526] 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 Tables 64A and 64B, and the aberration diagrams are shown in ​ .

[0527] [Table 61]

[0528] Example 16

[0529] ​ R D ​ ​ ​ ​ *1 2604.1624 1.0307 1.69350 53.20 10.95 4.36 *2 4.6879 2.7816 7.52 3 15.1597 1.8534 1.81600 46.62 6.95 4 -16.9889 0.6206 6.33 *5 -5.8859 1.1196 1.85135 40.10 5.92 *6 -9.6033 0.2203 5.60 7 16.9982 1.2761 1.64850 53.02 5.63 8 -16.4573 1.2496 5.53 ​ ∞ 1.4233 *10 9.8571 1.3844 1.73077 40.50 5.00 *11 -16.9954 ​ 5.33 12 -14.8550 1.3684 1.43875 94.66 5.64 13 -4.6429 2.2767 1.95906 17.47 5.84 14 -12.1712 ​ 7.60 *15 -34992.7611 1.2764 1.80139 45.45 8.14 0.03 / 1.35 / 2.35 / 3.62 *16 -7.3511 1.0349 8.42 2.35 / 4.04 *17 -7.1998 1.1342 1.68948 31.02 8.46 *18 24.1588 1.0000 10.74 1.02 19 ∞ 1.3800 1.51680 64.20 20 ∞ 0.6366

[0530] [Table 62]

[0531] Example 16

[0532] f 5.93 ​ 2.55 ​ 1.85 ​ 106.6

[0533] [Table 63]

[0534] Example 16

[0535] ​ 0.150m ​ 0.6925 0.9258 ​ 0.2906 0.0573

[0536] [Table 64A]

[0537] Example 16

[0538]

[0539] [Table 64B]

[0540] Example 16

[0541] ​ 17 18 ​ 1.2735921E+00 -2.6960463E+03 A3 -1.4103622E-17 2.0486435E-17 A4 1.5602855E-03 -5.8068077E-05 A5 -2.9477598E-04 -1.1318606E-04 A6 -1.1794752E-05 3.5055245E-06 A7 8.2679643E-09 -4.6304653E-07 A8 9.0211931E-08 -5.1761862E-08 A9 1.5866724E-09 1.5069989E-09 A10 -4.3978694E-10 3.1275551E-10 A11 -8.4095535E-12 -1.7292132E-12 A12 1.3934328E-12 -1.0613378E-12 A13 2.5396168E-14 -3.1412916E-15 A14 -2.8824787E-15 2.1503687E-15 A15 -4.4979969E-17 1.3092821E-17 A16 3.7726031E-18 -2.5762005E-18 A17 4.2863504E-20 -1.6381166E-20 A18 -2.8461558E-2l 1.682632lE-21 A19 -1.6821843E-23 7.3858930E-24 A20 9.4435681E-25 -4.5991 776E-25

[0542] [Example 17]

[0543] A cross-sectional view of the structure of the imaging lens of Example 17 is shown in ​ . The imaging lens of Example 17 includes, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2 having a positive refractive power, and a third lens group G3 having a negative refractive power. The focusing group includes the second lens group G2, and when focusing from an infinite object to the nearest object, the focusing group moves toward the object side along the optical axis Z

[0544] The first lens group G1 includes, in order from the object side to the image side, lenses L11 to L13, an aperture stop St, and lenses L14 to L16. The second lens group G2 includes one lens L21. The third lens group G3 includes two lenses L31 to L32 in order from the object side to the image side.

[0545] Regarding the imaging lens of Example 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 Tables 68A and 68B, and each aberration diagram is shown in ​ .

[0546] [Table 65]

[0547] Example 17

[0548] ​ R D ​ ​ ​ ​ *1 86.4215 0.8167 1.69350 53.20 11.47 *2 4.6987 1.9973 8.02 3 25.0095 2.4606 2.00272 19.32 7.76 4 112.8184 0.1138 6.13 *5 18.9462 0.9882 1.80610 40.73 5.78 1.69 *6 45.4549 1.3482 5.01 ​ ∞ 1.0177 8 -27.1688 0.7162 1.98613 16.48 5.21 9 57.0931 0.1029 5.46 *10 68.6420 1.8889 1.76802 49.24 5.55 *11 -8.2059 0.0999 5.89 *12 12.7982 0.8506 1.69350 53.20 6.78 (3.26) *13 22.0496 ​ 7.03 14 19.6545 2.7347 1.62041 60.29 8.27 15 -10.2569 ​ 8.70 *16 -178.7388 1.3683 1.58313 59.46 8.64 *17 -10.0287 0.6522 8.78 18 -9.0651 0.6998 2.00069 25.46 8.76 19 -4551.9398 2.8474 9.62 20 ∞ 1.3800 1.51680 64.20 21 ∞ 0.7072

[0549] [Table 66]

[0550] Example 17

[0551] f 5.75 ​ 4.46 ​ 1.86 ​ 107.0

[0552] [Table 67]

[0553] Example 17

[0554] ​ 0.150m ​ 1.1998 1.0334 ​ 1.0000 1.1664

[0555] [Table 68A]

[0556] Example 17

[0557]

[0558]

[0559] [Table 68B]

[0560] Example 17

[0561] ​ 16 17 ​ 1.0000000E+00 1.0000000E+00 A3 -2.6020852E-19 6.9388939E-19 A4 -4.8257580E-04 2.4231588E-03 A5 1.8535519E-04 -4.9582443E-04 A6 4.1875714E-06 8.5526156E-05 A7 -1.6773510E-05 3.0756623E-05 A8 -9.8371608E-07 -1.3198820E-05 A9 6.6521517E-07 -1.2475873E-06 A10 3.1362003E-08 5.8670001E-07 A11 -1.5688034E-08 3.0758521E-08 A12 -2.8539526E-10 -1.4026653E-08 A13 2.2832384E-10 -4.6476014E-10 A14 -3.2834481E-12 2.0000231E-10 A15 -2.0075665E-12 4.2060656E-12 A16 9.0551584E-14 -1.7034895E-12 A17 9.7705505E-15 -2.0919415E-14 A18 -7.0550021E-16 8.0140628E-15 A19 -2.0196558E-17 4.3944269E-17 A20 1.9259437E-18 -1.6044904E-17

[0562] [Example 18]

[0563] A cross-sectional view of the structure of the imaging lens of Example 18 is shown in ​ . The imaging lens of Example 18 includes, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2 having a positive refractive power, and a third lens group G3 having a negative refractive power. The focusing group includes the second lens group G2, and when focusing from an infinitely distant object to the nearest object, the focusing group moves toward the object side along the optical axis Z.

[0564] The first lens group G1 includes, in order from the object side to the image side, lenses L11 to L13, an aperture stop St, and lenses L14 to L16. The second lens group G2 includes a single lens L21. The third lens group G3 includes two lenses L31 to L32 in order from the object side to the image side.

[0565] Regarding the imaging lens of Example 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 Tables 72A and 72B, and the aberration diagrams are shown in ​ .

[0566] [Table 69]

[0567] Example 18

[0568] ​ R D ​ ​ ​ ​ *1 209.8548 0.7998 1.69350 53.20 11.44 *2 4.8528 1.9809 8.05 3 29.1198 2.0867 2.00069 25.46 7.72 4 170.4272 0.0999 6.29 *5 19.5688 0.8159 1.80610 40.73 5.93 1.72 *6 45.8972 1.5816 5.24 ​ ∞ 1.0004 8 -69.5044 0.7017 2.10420 17.02 5.27 9 48.1658 0.0998 5.45 *10 84.3797 1.8202 1.76802 49.24 5.52 *11 -8.2949 0.0998 5.81 *12 12.7785 0.8367 1.61881 63.85 6.59 (2.64) *13 22.3471 ​ 6.89 14 43.6406 2.4467 1.69680 55.46 8.22 15 -10.7829 ​ 8.76 *16 -127.3272 1.7764 1.69350 53.20 8.92 *17 -9.8499 0.5778 9.22 18 -8.9431 0.7002 1.92286 20.88 9.17 19 2968494.4385 2.9422 10.04 20 ∞ 1.3800 1.51680 64.20 21 ∞ 0.7094

[0569] [Table 70]

[0570] Example 18

[0571] f 5.75 ​ 4.56 ​ 1.86 ​ 108.4

[0572] [Table 71]

[0573] Example 18

[0574] ​ 0.150m ​ 1.5311 1.3317 ​ 0.9998 1.1992

[0575] [Table 72A]

[0576] Example 18

[0577]

[0578]

[0579] [Table 72B]

[0580] Example 18

[0581] ​ 16 17 ​ 1.0000000E+00 1.0000000E+00 A3 -3.4694470E-19 1.7347235E-19 A4 -6.4853930E-04 1.7309040E-03 A5 1.7296261E-04 -5.9020461E-04 A6 3.8278605E-05 1.3205076E-04 A7 -1.5036211E-05 3.6055645E-05 A8 -3.3404612E-06 -1.5278769E-05 A9 5.7626427E-07 -1.3959699E-06 A10 1.2328150E-07 6.4649355E-07 A11 -1.3240501E-08 3.3318240E-08 A12 -2.4549122E-09 -1.5146693E-08 A13 1.8912507E-10 -4.9181155E-10 A14 2.8295304E-11 2.1371053E-10 A15 -1.6407523E-12 4.3728001E-12 A16 -1.8649311E-13 -1.8089937E-12 A17 7.9107796E-15 -2.1450866E-14 A18 6.3753599E-16 8.4735386E-15 A19 -1.6249768E-17 4.4578866E-17 A20 -8.3738328E-19 -1.6898058E-17

[0582] [Example 19]

[0583] A cross-sectional view of the structure of the imaging lens of Example 19 is shown in ​ . The imaging lens of Example 19 includes, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2 having a positive refractive power, and a third lens group G3 having a negative refractive power. The focusing group includes the second lens group G2, and when focusing from an infinitely distant object to the nearest object, the focusing group moves toward the object side along the optical axis Z.

[0584] The first lens group G1 includes, in order from the object side to the image side, lenses L11 to L12, an aperture stop St, and lenses L13 to L15. The second lens group G2 includes one lens L21. The third lens group G3 includes two lenses L31 to L32 in order from the object side to the image side.

[0585] Regarding the imaging lens of Example 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 Tables 76A and 76B, and each aberration diagram is shown in ​ .

[0586] [Table 73]

[0587] Example 19

[0588] ​ R D ​ ​ ​ ​ *1 262.7694 1.0584 1.76802 49.24 10.85 *2 4.8317 1.8962 7.39 *3 9.4996 2.2297 1.68948 31.02 6.59 2.65 *4 28.2179 1.4410 4.78 ​ ∞ 1.0586 6 -64.6071 0.6560 2.10420 17.02 5.39 7 52.8543 0.0998 5.60 *8 65.9432 2.1177 1.76802 49.24 5.69 *9 -8.1281 0.0998 6.10 *10 13.2083 0.8458 1.69350 53.20 6.93 (3.1) *11 22.4824 ​ 7.21 12 18.3518 3.7265 1.49700 81.61 8.51 13 -8.2933 ​ 9.24 *14 -177.2737 1.7368 1.55332 71.68 9.15 *15 -9.7710 0.8853 9.54 16 -8.2927 0.7399 1.92286 20.88 9.35 17 3898046.9983 2.1113 10.42 18 ∞ 1.3800 1.51680 64.20 19 ∞ 0.7079

[0589] [Table 74]

[0590] Example 19

[0591] f 5.75 ​ 3.73 ​ 1.87 ​ 108.6

[0592] [Table 75]

[0593] Example 19

[0594] ​ 0.150m ​ 1.1998 1.0186 ​ 0.9998 1.1810

[0595] [Table 76A]

[0596] Example 19

[0597]

[0598] [Table 76B]

[0599] Example 19

[0600] ​ 14 15 ​ 1.0000000E+00 1.0000000E+00 A3 -7.8062556E-19 1.2143064E-18 A4 -9.2678506E-04 1.8504522E-03 A5 -2.0259214E-05 -7.2952571E-04 A6 6.1828951E-05 1.2782093E-04 A7 -9.1738262E-06 3.8399437E-05 A8 -5.3039832E-06 -1.6035175E-05 A9 4.2059999E-07 -1.4016369E-06 A10 2.0590270E-07 7.0591029E-07 A11 -1.0474585E-08 3.2411556E-08 A12 -4.4196566E-09 -1.7055972E-08 A13 1.5795219E-10 -4.6945990E-10 A14 5.6234846E-11 2.4702727E-10 A15 -1.4271443E-12 4.1232369E-12 A16 -4.2312584E-13 -2.1389521E-12 A17 7.0977043E-15 -2.0054974E-14 A18 1.7417120E-15 1.0217868E-14 A19 -1.4925166E-17 4.1416811E-17 A20 -3.0269430E-18 -2.0724265E-17

[0601] [Example 20]

[0602] A cross-sectional view of the structure of the imaging lens of Example 20 is shown in ​ . The imaging lens of Example 20 includes, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2 having a positive refractive power, and a third lens group G3 having a negative refractive power. The focusing group includes the second lens group G2, and when focusing from an infinitely distant object to the nearest object, the focusing group moves toward the object side along the optical axis Z.

[0603] The first lens group G1 includes, in order from the object side to the image side, lenses L11 to L12, an aperture stop St, and lenses L13 to L15. The second lens group G2 includes one lens L21. The third lens group G3 includes three lenses L31 to L33 in order from the object side to the image side.

[0604] Regarding the imaging lens of Example 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 Tables 80A and 80B, and the aberration diagrams are shown in ​ .

[0605] [Table 77]

[0606] Example 20

[0607] ​ R D ​ ​ ​ ​ *1 300.0139 1.0413 1.76802 49.24 10.63 *2 4.7553 2.2318 7.24 *3 8.8629 1.6748 1.68948 31.02 6.04 2.52 *4 30.0245 1.3990 4.72 ​ ∞ 1.0042 6 -59.3154 0.5998 1.94595 17.98 5.37 7 35.2754 0.1002 5.57 *8 66.7997 2.0184 1.76802 49.24 5.65 *9 -8.3302 0.0998 6.02 *10 12.7601 1.0030 1.58313 59.46 6.83 (2.63) *11 25.6861 ​ 7.20 12 50.7043 2.2505 1.88100 40.14 8.23 13 -12.7412 ​ 8.69 *14 -218.1780 1.3032 1.49710 81.56 8.73 *15 -9.6677 0.3593 9.02 16 -14.4378 0.6998 2.10420 17.02 9.01 17 33.1903 1.8098 1.77250 49.62 9.60 18 ∞ 2.9515 10.27 19 ∞ 1.3800 1.51680 64.20 20 ∞ 0.7021

[0608] [Table 78]

[0609] Example 20

[0610] f 5.74 ​ 4.56 ​ 1.87 ​ 107.8

[0611] [Table 79]

[0612] Example 20

[0613] ​ 0.150m ​ 1.3381 1.1661 ​ 1.0186 1.1906

[0614] [Table 80A]

[0615] Example 20

[0616]

[0617] [Table 80B]

[0618] Example 20

[0619] ​ 14 15 ​ 1.0000000E+00 1.0000000E+00 A3 -1.4528309E-18 6.9388939E-19 A4 -4.5821204E-04 2.7458741E-03 A5 -9.0894067E-05 -6.5873548E-04 A6 5.2012299E-06 5.3341935E-05 A7 -3.2820389E-06 3.6673664E-05 A8 -1.9507436E-06 -1.2505141E-05 A9 1.4283251E-07 -1.3780405E-06 A10 8.8164739E-08 6.0300028E-07 A11 -2.7135721E-09 3.2338207E-08 A12 -1.8719881E-09 -1.5128136E-08 A13 2.9012785E-11 -4.7124084E-10 A14 2.1886295E-11 2.2350273E-10 A15 -1.7903486E-13 4.1416960E-12 A16 -1.4135693E-13 -1.9572761E-12 A17 5.9695887E-16 -2.0087977E-14 A18 4.5246004E-16 9.4111580E-15 A19 -8.5209488E-19 4.1266386E-17 A20 -5.0113093E-19 -1.9159017E-17

[0620] [Example 21]

[0621] A cross-sectional view of the structure of the imaging lens of Example 21 is shown in ​ . The imaging lens of Example 21 includes, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2 having a positive refractive power, and a third lens group G3 having a negative refractive power. The focusing group includes the second lens group G2, and when focusing from an infinitely distant object to the nearest object, the focusing group moves toward the object side along the optical axis Z.

[0622] The first lens group G1 includes, in order from the object side to the image side, lenses L11 to L12, an aperture stop St, and lenses L13 to L15. The second lens group G2 includes one lens L21. The third lens group G3 includes three lenses L31 to L33 in order from the object side to the image side.

[0623] Regarding the imaging lens of Example 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 Tables 84A and 84B, and each aberration diagram is shown in ​ .

[0624] [Table 81]

[0625] Example 21

[0626] ​ R D ​ ​ ​ ​ *1 245.6990 0.7998 1.76802 49.24 12.69 *2 5.0439 4.1599 9.03 *3 13.1800 2.1243 1.80610 40.73 7.58 2.59 *4 -21.6209 1.2053 7.02 ​ ∞ 1.4405 *6 -13.0477 0.8203 1.68948 31.02 5.09 *7 15.2010 0.1230 5.44 *8 20.0509 2.0074 1.76802 49.24 5.47 *9 -8.0006 0.4019 5.84 10 53.6085 0.6225 1.75520 27.53 6.67 11 20.6203 ​ 6.97 12 63.3218 3.0590 1.71300 53.94 8.22 13 -8.5686 ​ 9.01 *14 -80.3447 1.2468 1.69350 53.20 9.03 *15 -12.6157 0.1428 9.29 16 -15.0417 0.6998 1.84666 23.78 9.30 17 10.3172 3.1729 1.71300 53.94 10.16 18 -128.1759 2.9038 10.16 19 ∞ 1.3800 1.51680 64.20 20 ∞ 0.6952

[0627] [Table 82]

[0628] Example 21

[0629] f 5.75 ​ 4.51 ​ 1.97 ​ 109.8

[0630] [Table 83]

[0631] Example 21

[0632] ​ 0.150m ​ 1.3984 1.2164 ​ 0.9998 1.1818

[0633] [Table 84A]

[0634] Example 21

[0635]

[0636] [Table 84B]

[0637] Example 21

[0638] ​ 14 15 ​ 1.0000000E+00 1.0000000E+00 A3 5.2041704E-19 1.7347235E-19 A4 -8.5130526E-04 4.8444631E-04 A5 1.6636945E-04 -2.1117428E-04 A6 5.8093429E-05 9.8218554E-05 A7 -1.5563652E-05 1.4455607E-05 A8 -4.0663184E-06 -1.0762855E-05 A9 5.9375969E-07 -5.7477205E-07 A10 1.4246194E-07 4.7956156E-07 A11 -1.3615825E-08 1.3784195E-08 A12 -2.9352710E-09 -1.1887896E-08 A13 1.9332667E-10 -2.0314331E-10 A14 3.7426457E-11 1.7631764E-10 A15 -1.6600537E-12 1.7976840E-12 A16 -2.9054784E-13 -1.5547434E-12 A17 7.8984429E-15 -8.7634385E-15 A18 1.2584889E-15 7.5200209E-15 A19 -1.5983618E-17 1.8087039E-17 A20 -2.3333170E-18 -1.5373337E-17

[0639] [Example 22]

[0640] A cross-sectional view of the structure of the imaging lens of Example 22 is shown in ​ . The imaging lens of Example 22 includes, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2 having a positive refractive power, and a third lens group G3 having a positive refractive power. The focusing group includes the second lens group G2, and when focusing from an infinite object to the nearest object, the focusing group moves toward the object side along the optical axis Z.

[0641] The first lens group G1 includes, in order from the object side to the image side, lenses L11 to L13, an aperture stop St, and a lens L14. The second lens group G2 includes one lens L21. The third lens group G3 includes four lenses L31 to L34 in order from the object side to the image side.

[0642] Regarding the imaging lens of Example 22, the basic lens data is shown in Table 85, the specifications are shown in Table 86, the variable surface intervals are shown in Table 87, the aspherical coefficients are shown in Tables 88A and 88B, and each aberration diagram is shown in ​ .

[0643] [Table 85]

[0644] Example 22

[0645] ​ R D ​ ​ ​ ​ *1 79.5168 0.7998 1.59201 67.02 10.84 4.36 *2 5.9928 0.6249 8.69 3.23 3 14.1393 0.7445 1.49700 81.61 8.53 4 3.7904 1.1687 6.19 *5 5.7132 1.8602 1.69350 53.20 5.92 *6 24.1925 1.3642 4.75 ​ ∞ 1.0406 *8 44.1000 1.7342 1.76802 49.24 5.09 *9 -11.8104 ​ 5.17 (2.2) 10 -11021.8453 2.2280 1.77250 49.62 6.71 11 -7.9023 ​ 7.45 12 -11.8907 0.6999 1.92286 20.88 7.74 13 13.5831 2.8235 1.83481 42.72 8.64 14 -20.3968 0.1002 9.43 *15 -192.3878 1.1731 1.85135 40.10 9.61 *16 -10.4589 0.4574 10.06 3.1 *17 -15.8706 1.1430 1.68948 31.02 10.57 3.73 *18 -144.9070 2.7809 11.49 1.02 / 2.39 19 ∞ 1.3800 1.51680 64.20 20 ∞ 0.7092

[0646] [Table 86]

[0647] Example 22

[0648] f 5.74 ​ 4.40 ​ 1.86 ​ 108.6

[0649] [Table 87]

[0650] Example 22

[0651] ​ 0.150m ​ 1.2826 1.0966 ​ 1.0002 1.1862

[0652] [Table 88A]

[0653] Example 22

[0654]

[0655] [Table 88B]

[0656] Example 22

[0657] ​ 17 18 ​ 1.0000000E+00 1.0000000E+00 A3 8.6736174E-19 -2.3852448E-19 A4 5.2881854E-04 7.5517705E-04 A5 2.8975245E-04 -4.0336521E-05 A6 -1.5689966E-04 -5.7965779E-05 A7 -1.5263140E-05 5.1096167E-06 A8 1.2288964E-05 1.2043681E-06 A9 5.8027885E-07 -2.2573948E-07 A10 -5.0044401E-07 -7.5381310E-10 A11 -1.3576988E-08 5.0033124E-09 A12 1.1945009E-08 -7.6490990E-10 A13 1.9442148E-10 -6.3891834E-11 A14 -1.7423282E-10 2.1502247E-11 A15 -1.6683315E-12 4.7726874E-13 A16 1.5301359E-12 -2.7675023E-13 A17 7.8887434E-15 -1.9425780E-15 A18 -7.4332744E-15 1.7608035E-15 A19 -1.5818592E-17 3.3356960E-18 A20 1.5347766E-17 -4.4675684E-18

[0658] [Example 23]

[0659] A cross-sectional view of the structure of the imaging lens of Example 23 is shown in ​ . The imaging lens of Example 23 includes, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2 having a positive refractive power, and a third lens group G3 having a positive refractive power. The focusing group includes the second lens group G2, and when focusing from an infinite object to the nearest object, the focusing group moves toward the object side along the optical axis Z.

[0660] The first lens group G1 includes, in order from the object side to the image side, lenses L11 to L13, an aperture stop St, and lenses L14 to L16. The second lens group G2 includes one lens L21. The third lens group G3 includes two lenses L31 to L32 in order from the object side to the image side.

[0661] Regarding the imaging lens of Example 23, the basic lens data is shown in Table 89, the specifications are shown in Table 90, the variable surface intervals are shown in Table 91, the aspherical coefficients are shown in Tables 92A and 92B, and each aberration diagram is shown in ​ .

[0662] [Table 89]

[0663] Example 23

[0664] ​ R D ​ ​ ​ ​ *1 254.1892 0.8001 1.49710 81.56 11.62 4.78 *2 5.9749 1.0933 8.85 3.68 3 25.0116 0.6998 1.49700 81.61 8.68 4 4.0701 1.5259 6.40 *5 5.6514 1.9915 1.76802 49.24 5.90 *6 26.9995 1.6907 4.78 ​ ∞ 1.0221 *8 117.9003 1.5943 1.76802 49.24 5.04 *9 -11.7829 0.1410 5.03 (2.12) 10 13.8209 1.8351 1.80420 46.50 5.65 11 -17.2013 0.7002 1.92286 20.88 6.00 12 15.3911 ​ 6.42 13 59.6537 2.5902 1.71300 53.94 8.40 14 -10.7330 ​ 9.31 *15 -151.4341 1.1661 1.69350 53.20 10.06 *16 -12.7981 0.2369 10.62 3.54 *17 -21.4071 0.7998 1.68948 31.02 11.15 3.51 *18 -292.6618 2.2429 11.97 1.08 / 2.56 19 1.3800 1.51680 64.20 20 ∞ 0.7117

[0665] [Table 90]

[0666] Example 23

[0667] f 5.75 ​ 3.86 ​ 1.86 ​ 114.2

[0668] [Table 91]

[0669] Example 23

[0670] ​ 0.150m ​ 1.5273 1.2068 ​ 1.2998 1.6203

[0671] [Table 92A]

[0672] Example 23

[0673]

[0674] [Table 92B]

[0675] Example 23

[0676] ​ 17 18 ​ 1.0000000E+00 1.0000000E+00 A3 4.9873300E-19 -1.9515639E-19 A4 -2.8930658E-03 3.4328670E-04 A5 -1.2019175E-05 -2.2242335E-05 A6 2.6702450E-04 -2.3526373E-05 A7 2.5193898E-06 2.1619138E-06 A8 -1.2672262E-05 5.8285556E-07 A9 -5.3626904E-08 -8.2334120E-08 A10 3.8173874E-07 -9.4815814E-09 A11 3.2777373E-10 1.9633000E-09 A12 -7.5031578E-09 -9.6056849E-11 A13 5.7772350E-12 -2.7962988E-11 A14 9.5145763E-11 5.3152709E-12 A15 -1.2792636E-13 2.3562712E-13 A16 -7.4909320E-13 -7.3791686E-14 A17 9.3877359E-16 -1.0923428E-15 A18 3.3300554E-15 4.6200208E-16 A19 -2.4702084E-18 2.1550272E-18 A20 -6.3849889E-1 8 -1.1202312E-18

[0677] [Example 24]

[0678] A cross-sectional view of the structure of the imaging lens of Example 24 is shown in ​ . The imaging lens of Example 24 includes, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2 having a positive refractive power, and a third lens group G3 having a negative refractive power. The focusing group includes the second lens group G2, and when focusing from an infinite object to the nearest object, the focusing group moves toward the object side along the optical axis Z.

[0679] The first lens group G1 includes, in order from the object side to the image side, lenses L11 to L13, an aperture stop St, and lenses L14 to L16. The second lens group G2 includes one lens L21. The third lens group G3 includes two lenses L31 to L32 in order from the object side to the image side.

[0680] Regarding the imaging lens of Example 24, the basic lens data is shown in Table 93, the specifications are shown in Table 94, the variable surface intervals are shown in Table 95, the aspherical coefficients are shown in Tables 96A and 96B, and each aberration diagram is shown in ​ .

[0681] [Table 93]

[0682] Example 24

[0683] ​ R D ​ ​ ​ ​ *1 52.2697 0.9723 1.69350 53.20 10.58 *2 4.5215 2.0953 7.18 3 50.4760 1.2207 1.92119 23.96 6.80 4 -156.2324 0.0997 6.05 *5 17.7989 0.9253 1.80610 40.73 5.59 1.83 *6 22.0718 1.5167 4.98 ​ ∞ 1.0134 8 -104.5029 0.8110 2.10420 17.02 5.46 9 33.4251 0.0998 5.69 *10 36.9426 1.9364 1.76802 49.24 5.77 *11 -8.4557 0.0998 6.14 *12 12.9019 0.8041 1.49710 81.56 7.01 (3.49) *13 21.4995 ​ 7.31 14 18.1497 3.4597 1.59282 68.62 8.65 15 -8.9091 ​ 9.19 *16 -300.0328 1.0246 1.55332 71.68 8.84 *17 -11.8663 0.7688 9.01 18 -8.8786 0.6998 1.92286 20.88 8.96 19 -10500025.1347 2.8513 9.86 20 ∞ 1.3800 1.51680 64.20 21 ∞ 0.7000

[0684] [Table 94]

[0685] Example 24

[0686] f 5.75 ​ 4.46 ​ 1.86 ​ 108.4

[0687] [Table 95]

[0688] Example 24

[0689] ​ 0.150m ​ 1.2727 1.1189 ​ 1.2312 1.3850

[0690] [Table 96A]

[0691] Example 24

[0692]

[0693]

[0694] [Table 96B]

[0695] Example 24

[0696] ​ 16 17 ​ 1.0000000E+00 1.0000000E+00 A3 -3.4694470E-19 1.9081958E-18 A4 -1.8793690E-03 7.0074950E-04 A5 -3.7481549E-06 -6.0548037E-04 A6 1.2629869E-04 1.7179441E-04 A7 -1.1439962E-05 3.5956599E-05 A8 -7.2106676E-06 -1.4360180E-05 A9 6.5834947E-07 -1.3932161E-06 A10 2.0745319E-07 5.2341013E-07 A11 -1.8289306E-08 3.2940659E-08 A12 -3.2196094E-09 -1.0770327E-08 A13 2.9109059E-10 -4.8035264E-10 A14 2.6095377E-11 1.3261509E-10 A15 -2.7012455E-12 4.2239406E-12 A16 -8.0765793E-14 -9.6337309E-13 A17 1.3595416E-14 -2.0547337E-14 A18 -1.8514810E-16 3.7805129E-15 A19 -2.8674013E-17 4.2483626E-17 A20 1.3323679E-18 -6.1111259E-18

[0697] [Example 25]

[0698] A cross-sectional view of the structure of the imaging lens of Example 25 is shown in ​ . The imaging lens of Example 25 includes, in order from the object side to the image side, a first lens group G1 having a positive refractive power, a second lens group G2 having a positive refractive power, and a third lens group G3 having a negative refractive power. The focusing group includes the second lens group G2, and when focusing from an infinitely distant object to the nearest object, the focusing group moves toward the object side along the optical axis Z.

[0699] The first lens group G1 includes, in order from the object side to the image side, lenses L11 to L12, an aperture stop St, and lenses L13 to L15. The second lens group G2 includes, in order from the object side to the image side, two lenses L21 to L22. The third lens group G3 includes, in order from the object side to the image side, two lenses L31 to L32.

[0700] Regarding the imaging lens of Example 25, the basic lens data is shown in Table 97, the specifications are shown in Table 98, the variable surface intervals are shown in Table 99, the aspherical coefficients are shown in Tables 100A and 100B, and each aberration diagram is shown in ​ .

[0701] [Table 97]

[0702] Example 25

[0703] ​ R D ​ ​ ​ ​ *1 299.9930 1.1139 1.69350 53.20 10.32 *2 4.5222 2.0949 6.94 *3 11.6505 1.3235 1.68948 31.02 5.72 2.44 *4 26.6250 1.4871 4.62 ​ ∞ 1.0002 6 52.8893 0.6958 1.92286 20.88 5.67 7 20.5788 0.1037 5.87 *8 36.6608 2.4550 1.76802 49.24 5.94 *9 -8.1581 0.0999 6.34 *10 13.2813 0.9856 1.76802 49.24 6.88 (1.99) *11 21.6431 ​ 7.14 12 32.3339 3.1840 1.72916 54.67 8.15 13 -8.2519 0.1075 8.71 14 -10.7421 0.7001 1.98613 16.48 8.55 15 -21.5232 ​ 8.85 *16 -23.1619 0.8373 1.58313 59.46 8.99 *17 -11.9105 0.5865 9.4l 2.09 / 3.11 18 -17.8193 0.6998 1.98613 16.48 9.57 19 -127.7478 2.8515 10.15 20 ∞ 1.3800 1.51680 64.20 21 ∞ 0.7039

[0704] [Table 98]

[0705] Example 25

[0706] f 5.74 ​ 4.47 ​ 1.86 ​ 109.4

[0707] [Table 99]

[0708] Example 25

[0709] ​ 0.150m ​ 1.2622 1.0289 ​ 1.3136 1.5469

[0710] [Table 100A]

[0711] Example 25

[0712]

[0713]

[0714] [Table 100B]

[0715] Example 25

[0716] ​ 16 17 ​ 1.0000000E+00 1.0000000E+00 A3 -3.4694470E-19 -3.4694470E-19 A4 -4.6664991E-04 2.3284159E-03 A5 8.1271070E-05 -4.4942832E-04 A6 9.3059222E-05 1.3177733E-04 A7 -1.6983526E-05 2.4637194E-05 A8 -8.6966112E-06 -1.7049535E-05 A9 7.5190070E-07 -9.0536150E-07 A10 3.6129795E-07 7.2907597E-07 A11 -1.8428223E-08 2.1572207E-08 A12 -8.4671611E-09 -1.6901579E-08 A13 2.7419349E-10 -3.2208802E-10 A14 1.1970806E-10 2.3389725E-10 A15 -2.4488836E-12 2.8958759E-12 A16 -1.0158844E-12 -1.9335785E-12 A17 1.2052774E-14 -1.4303671E-14 A18 4.7777798E-15 8.8262280E-15 A19 -2.5124755E-17 2.9788943E-17 A20 -9.5897697E-18 -1.7136874E-17

[0717] The corresponding values of conditional expressions (1) to (26) of the imaging lenses of Examples 1 to 25 are shown in Tables 101 to 109. In the column of the corresponding values of conditional expressions (16) and (17), the surface numbers of the surfaces having specific intersections are marked with "S" and shown in parentheses before the corresponding values. For a surface having multiple inflection points on one surface, the corresponding values are separated by " / ". However, in the column of the corresponding values of conditional expressions (16) and (17), the description of the corresponding values that do not satisfy each conditional expression is omitted, and for a surface having no corresponding value that satisfies each conditional expression, "none" is recorded after the surface number. The corresponding values of the examples shown in Tables 101 to 109 can be used as the upper or lower limits of the conditional expressions to set the preferred range of the conditional expressions.

[0718] [Table 101]

[0719]

[0720] [Table 102]

[0721]

[0722] [Table 103]

[0723]

[0724] [Table 104]

[0725]

[0726] [Table 105]

[0727]

[0728] [Table 106]

[0729]

[0730] [Table 107]

[0731]

[0732] [Table 108]

[0733]

[0734] [Table 109]

[0735]

[0736] The imaging lenses of Examples 1 to 25 are all configured to be small, and the maximum full viewing angle in the state of focusing on an infinite object is 100 degrees or more, and are configured to be wide-angle. And, the F value of some of the examples is less than 2. The imaging lenses of Examples 1 to 25 correct various aberrations well and maintain high optical performance.

[0737] Next, a description will be given of the imaging device according to an embodiment of the present invention. In ​ and ​ figures are shown of the appearance of the camera 30 as an imaging device according to an embodiment of the present invention. ​ represents a perspective view of the camera 30 as viewed from the front side, ​ represents a perspective view of the camera 30 as viewed from the back side. The camera 30 is a so-called mirrorless digital camera and includes the imaging lens 1 according to an embodiment of the present invention accommodated in a lens barrel.

[0738] The camera 30 includes a camera body 31. A shutter button 32 and a power button 33 are provided on the upper surface of the camera body 31. Further, an operation unit 34, an operation unit 35, and a display unit 36 are provided on the back surface of the camera body 31. The display unit 36 can display the captured image and the image existing within the perspective before shooting.

[0739] An imaging element 38 is provided within the camera body 31. The imaging element 38 outputs a captured image signal corresponding to the subject image formed by the imaging lens 1. As the imaging element 38, for example, a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor) etc. can be used. A signal processing circuit (not shown) and a recording medium (not shown) etc. are provided within the camera body 31. The signal processing circuit processes the captured image signal output from the imaging element 38 to generate an image. The recording medium is used to record the generated image. In the camera 30, a still image or a moving image can be captured by pressing the shutter button 32, and the image data obtained by this capture is recorded in the above-mentioned recording medium.

[0740] As described above, the technology of the present invention has been described by way of embodiments and examples, but the technology of the present invention is not limited to the above-mentioned embodiments and examples, and various modifications can be made. For example, the curvature radius, surface interval, refractive index, Abbe number, aspherical coefficient, etc. of each lens are not limited to the values shown in the above-mentioned respective examples, and other values can be adopted.

[0741] The aberration diagrams of the above-mentioned embodiments are shown for the d-line, C-line, and F-line, but the technology of the present invention is not limited to this wavelength range, and can also be applied to imaging lenses with an expanded or reduced wavelength range. Thus, the imaging device of the present invention is not limited to a camera corresponding to the visible light region. The technology of the present invention can also be applied to, for example, a camera for the visible light region, a camera for the SWIR (Short Wave Infra-Red) region, a multi-spectral camera, a hyperspectral camera, a thermal imaging camera, etc.

[0742] In ​ a lens-fixed camera in which the imaging lens is fixed to the camera body is shown, but the imaging device of the present invention can also be a lens-interchangeable camera in which the imaging lens can be detachably mounted on the camera body. Further, the imaging device of the present invention can be configured as various types such as a camera other than the mirrorless type, a film camera, a video camera, a camera for FA (Factory Automation), a camera for MV (Machine Vision), a surveillance camera, a vehicle-mounted camera, and a movie camera.

[0743] Regarding the above-described embodiments and examples, the following supplementary notes are further disclosed.

[0744] [Supplementary Note 1]

[0745] An imaging lens that sequentially includes a first lens group, a second lens group, and a third lens group having positive refractive power from the object side to the image side,

[0746] During focusing, the first lens group and the third lens group are fixed relative to the image plane, and the second lens group moves along the optical axis,

[0747] The lens closest to the object side is a negative meniscus lens, and at least one of the second lens and the third lens from the object side is a lens other than a negative meniscus lens,

[0748] The aperture stop is disposed on the image side of the second lens from the object side,

[0749] When the distance on the optical axis from the lens surface closest to the object side of the first lens group to the lens surface closest to the image side of the third lens group and the sum of the back focal length of the entire system in terms of air-equivalent distance are set as TL,

[0750] The maximum image height is set as Y,

[0751] The focal length of the entire system in the state of focusing on an infinitely distant object is set as f,

[0752] 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 expressions (1) and (2):

[0753] 1 < TL / Y < 4.5 (1)

[0754] -0.18 < (Y - f×tanωm) / (f×tanωm) < -0.02 (2).

[0755] [Supplementary Note 2]

[0756] The imaging lens according to Supplementary Note 1, wherein

[0757] In a cross-section including the optical axis, when the radius of the circle passing through three points formed by a point on the optical axis of the lens surface and two points at the outermost ends of the effective diameter is set as Rc of the lens surface,

[0758] When the sign of Rc is set as positive when the point on the optical axis is closer to the object side than the center of the circle and negative when the point on the optical axis is closer to the image side than the center of the circle,

[0759] The number of lenses with an aspherical shape for the lens surface on the object side included in the third lens group and a negative sign for Rc of the lens surface on the object side is one or two.

[0760] [Supplementary Note 3]

[0761] The imaging lens according to Supplementary Note 1 or 2, wherein

[0762] The number of lenses included in the imaging lens is five or more and ten or less.

[0763] [Supplementary Note 4]

[0764] The imaging lens according to any one of Supplementary Notes 1 to 3, wherein

[0765] When the unit of ωm is degrees, the imaging lens satisfies the following conditional expression (3):

[0766] 47 < ωm < 60 (3).

[0767] [Supplementary Note 5]

[0768] The imaging lens according to any one of Supplementary Note Items 1 to 4, wherein

[0769] When the focal length of the first lens group is set to fG1, the imaging lens satisfies the following conditional expression (4):

[0770] 0.01 < f / fG1 < 1.6 (4).

[0771] [Supplementary Note 6]

[0772] The imaging lens according to any one of Supplementary Notes 1 to 5, wherein

[0773] When the distance on the optical axis from the lens surface closest to the object of the first lens group to the aperture in the state of focusing on an infinitely distant object is set to dL1St, the imaging lens satisfies the following conditional expression (5):

[0774] 0.1 < dLlSt / Y < 2.1 (5).

[0775] [Supplementary Note 7]

[0776] The imaging lens according to any one of Supplementary Notes 1 to 6, wherein

[0777] When the angle formed by the principal ray of the maximum image height incident on the image plane and the axis parallel to the optical axis in the state of focusing on an infinitely distant object is set to CRA,

[0778] When the unit of CRA is degrees, the imaging lens satisfies the following conditional expression (6):

[0779] 16 < |CRA| < 69 (6).

[0780] [Supplementary Note 8]

[0781] The imaging lens according to any one of Supplementary Notes 1 to 7, wherein,

[0782] When the back focal length of the entire system in terms of air equivalent distance is set to Bf, the imaging lens satisfies the conditional expression (7) shown below:

[0783] 0.06 < Bf / TL < 0.3 (7).

[0784] [Supplementary Note 9]

[0785] The imaging lens according to any one of Supplementary Notes 1 to 8, wherein,

[0786] When the unit of f is set to millimeters,

[0787] When the open F value in the state of focusing on an infinitely distant object is set to Fno, the imaging lens satisfies the conditional expression (8) shown below:

[0788] 1.7 < f / Fno < 4.1 (8).

[0789] [Supplementary Note 10]

[0790] The imaging lens according to any one of Supplementary Notes 1 to 9, wherein,

[0791] When the focal length of the second lens group is set to fG2, the imaging lens satisfies the conditional expression (9) shown below:

[0792] 0.24 < |f / fG2| < 2.4 (9).

[0793] [Supplementary Note 11]

[0794] The imaging lens according to any one of Supplementary Notes 1 to 10, wherein,

[0795] One or two single lenses with negative refractive power and one or two single lenses with positive refractive power are arranged on the object side of the diaphragm,

[0796] The number of lenses arranged on the object side of the diaphragm is 4 or less.

[0797] [Supplementary Note 12]

[0798] The imaging lens according to any one of Supplementary Notes 1 to 11, wherein,

[0799] When a positive lens is arranged adjacent to the image side of the diaphragm,

[0800] When the Abbe number of the positive lens adjacent to the image side of the diaphragm with respect to the d-line is set as vrp, the imaging lens satisfies the conditional expression (10) shown below:

[0801] 34 < vrp < 87 (10).

[0802] [Supplementary Note 13]

[0803] According to the imaging lens described in any one of Supplementary Notes 1 to 12, wherein,

[0804] when the positive lens is disposed adjacent to the object side of the diaphragm,

[0805] when the Abbe number of the positive lens adjacent to the object side of the diaphragm with respect to the d-line is set as vfp, the imaging lens satisfies the conditional expression (11) shown below:

[0806] 23 < vfp < 61 (11).

[0807] [Supplementary Note 14]

[0808] According to the imaging lens described in any one of Supplementary Notes 1 to 13, wherein,

[0809] when the positive lens is disposed adjacent to the object side of the diaphragm and the Lffn lens having a negative refractive power is disposed adjacent to the object side of the positive lens,

[0810] when the Abbe number of the Lffn lens with respect to the d-line is set as vffn, the imaging lens satisfies the conditional expression (12) shown below:

[0811] 16 < vffn < 100 (12).

[0812] [Supplementary Note 15]

[0813] According to the imaging lens described in any one of Supplementary Notes 1 to 14, wherein,

[0814] in a cross-section including the optical axis, when the radius of the circle passing through three points consisting of the point on the optical axis of the lens surface and the two outermost points of the effective diameter is set as Rc of the lens surface,

[0815] when the sign of Rc is set as positive when the point on the optical axis is closer to the object side than the center of the circle and set as negative when the point on the optical axis is closer to the image side than the center of the circle,

[0816] the first lens group successively includes a negative partial group and one positive lens continuously from the object side to the image side,

[0817] the negative partial group includes one or two negative lenses having the same sign for the Rc of the object-side lens surface and the Rc of the image-side lens surface,

[0818] At least one lens surface included in the negative lens group is an aspherical shape,

[0819] When the average value of the refractive indices of all the lenses included in the negative lens group with respect to the d-line is set as N1nave,

[0820] and the average value of the Abbe numbers of all the lenses included in the negative lens group with respect to the d-line is set as v1nave, the imaging lens satisfies the following conditional expressions (13) and (14):

[0821] 1.45 < N1nave < 2.3 (13)

[0822] 16 < v1nave < 85 (14).

[0823] [Supplementary Note 16]

[0824] The imaging lens according to any one of Supplementary Notes 1 to 15, wherein

[0825] when the combined focal length of all the lenses on the object side of the diaphragm is set as fGf in the state of focusing on an infinitely distant object,

[0826] and the combined focal length of all the lenses on the image side of the diaphragm is set as fGr in the state of focusing on an infinitely distant object, the imaging lens satisfies the following conditional expression (15):

[0827] -10 < fGf / fGr < 31 (15).

[0828] [Supplementary Note 17]

[0829] The imaging lens according to any one of Supplementary Notes 1 to 16, wherein

[0830] the lens surface closest to the image side of the second lens group is a convex shape.

[0831] [Supplementary Note 18]

[0832] The imaging lens according to any one of Supplementary Notes 1 to 17, wherein

[0833] the imaging lens includes at least one lens surface having an inflection point,

[0834] and when the distance on the optical axis from the lens surface closest to the object side of the first lens group to the lens surface closest to the image side of the third lens group is set as DL,

[0835] In a state where the object is focused at infinity, at least one of the intersections of the lens surface having an inflection point with the optical axis is a specific intersection, and the specific intersection is within a range of 0.3×DL toward the image side from the intersection of the lens surface closest to the object side of the first lens group with the optical axis, or within a range of 0.3×DL toward the object side from the intersection of the lens surface closest to the image side of the third lens group with the optical axis.

[0836] [Note 19]

[0837] The imaging lens according to Note 18, wherein,

[0838] When the refractive power of the lens surface having the specific intersection is set to φa,

[0839] when the refractive power of the imaging lens in a state where the object is focused at infinity is set to φ,

[0840] at least one of the lens surfaces having the specific intersection satisfies the following conditional expression (16):

[0841] -2 < φa / φ < 3 (16).

[0842] [Note 20]

[0843] An imaging device including the imaging lens according to any one of Notes 1 to 19.

Claims

1. An imaging lens, which sequentially includes a first lens group, a second lens group, and a third lens group having positive refractive power from the object side to the image side. During focusing, the first lens group and the third lens group are fixed relative to the image plane, and the second lens group moves along the optical axis. The lens closest to the object side is a negative meniscus lens, and at least one of the second lens and the third lens from the object side is a lens other than a negative meniscus lens. The aperture stop is disposed closer to the image side than the second lens from the object side. When the distance on the optical axis from the lens surface closest to the object side of the first lens group to the lens surface closest to the image side of the third lens group and the sum of the back focal length of the entire system in terms of air equivalent distance are set as TL. The maximum image height is set as Y. The focal length of the entire system in the state of focusing on an infinite object is set as f. When the maximum half angle of view in the state of focusing on an infinite object is set as ωm, the imaging lens satisfies the following conditional expressions (1) and (2): 1 < TL / Y < 4.5 (1) -0.18 < (Y - f×tanωm) / (f×tanωm) < -0.02 (2).

2. The imaging lens according to claim 1, wherein In a cross section including the optical axis, when the radius of the circle passing through three points formed by the point on the optical axis of the lens surface and the two points at the outermost ends of the effective diameter is set as Rc of the lens surface. When the sign of Rc is set as positive when the point on the optical axis is closer to the object side than the center of the circle, and negative when the point on the optical axis is closer to the image side than the center of the circle. The number of lenses with an aspherical shape for the lens surface on the object side included in the third lens group and a negative sign for Rc of the lens surface on the object side is one or two.

3. The imaging lens according to claim 1 or 2, wherein The number of lenses included in the imaging lens is five or more and ten or less.

4. The imaging lens according to claim 1 or 2, wherein When the unit of ωm is set as degrees, the imaging lens satisfies the following conditional expression (3): 47 < ωm < 60 (3).

5. The imaging lens according to claim 1 or 2, wherein When the focal length of the first lens group is set as fG1, the imaging lens satisfies the following conditional expression (4): 0.01 < f / fG1 < 1.6 (4).

6. The imaging lens according to claim 1 or 2, wherein When the distance on the optical axis from the lens surface closest to the object side of the first lens group to the aperture stop in the state of focusing on an infinite object is set as dL1St. 0.1 < dL1St / Y < 2.1 (5).

7. The imaging lens according to claim 1 or 2, wherein When the angle formed by the principal ray of the maximum image height incident on the image plane and the axis parallel to the optical axis in the state of focusing on an infinite object is set as CRA. When the unit of CRA is set as degrees, the imaging lens satisfies the following conditional expression (6): 16 < |CRA| < 69 (6).

8. The imaging lens according to claim 1 or 2, wherein when the back focal length of the entire system in terms of air equivalent distance is set as Bf, the imaging lens satisfies the conditional expression (7) shown below: 0.06 < Bf / TL < 0.3 (7).

9. The imaging lens according to claim 1 or 2, wherein when the unit of f is set to millimeters, and the open F number in the state of focusing on an infinite object is set as Fno, the imaging lens satisfies the conditional expression (8) shown below: 1.7 < f / Fno < 4.1 (8).

10. The imaging lens according to claim 1 or 2, wherein when the focal length of the second lens group is set as fG2, the imaging lens satisfies the conditional expression (9) shown below: 0.24 < |f / fG2| < 2.4 (9).

11. The imaging lens according to claim 1 or 2, wherein one or two single lenses with negative refractive power and one or two single lenses with positive refractive power are arranged on the object side of the aperture stop, and the number of lenses arranged on the object side of the aperture stop is 4 or less.

12. The imaging lens according to claim 1 or 2, wherein when a positive lens is arranged adjacent to the image side of the aperture stop, and the Abbe number based on the d line of the positive lens arranged adjacent to the image side of the aperture stop is set as vrp, the imaging lens satisfies the conditional expression (10) shown below: 34 < vrp < 87 (10).

13. The imaging lens according to claim 1 or 2, wherein when a positive lens is arranged adjacent to the object side of the aperture stop, and the Abbe number based on the d line of the positive lens arranged adjacent to the object side of the aperture stop is set as vfp, the imaging lens satisfies the conditional expression (11) shown below: 23 < vfp < 61 (11).

14. The imaging lens according to claim 1 or 2, wherein when a positive lens is arranged adjacent to the object side of the aperture stop and a lens Lffn with negative refractive power is arranged adjacent to the object side of the positive lens, and the Abbe number based on the d line of the lens Lffn is set as vffn, the imaging lens satisfies the conditional expression (12) shown below: 16 < vffn < 100 (12).

15. The imaging lens according to claim 1, wherein in a cross section including the optical axis, when the radius of the circle passing through three points formed by the point on the optical axis of the lens surface and the two outermost points of the effective diameter is set as Rc of the lens surface, and the sign of Rc is set as positive when the point on the optical axis is closer to the object side than the center of the circle and negative when the point on the optical axis is closer to the image side than the center of the circle, the first lens group continuously includes a negative partial group and one positive lens in order from the object side to the image side, the negative partial group includes one or two negative lenses with the same sign of Rc of the object-side lens surface and the image-side lens surface, at least one lens surface included in the negative partial group is an aspherical shape, when the average value of the refractive indices of all the lenses included in the negative partial group with respect to the d line is set as N1nave, When the average value of the Abbe numbers of the d-line reference of all the lenses included in the negative lens group is set as v1nave, the imaging lens satisfies the conditional expressions (13) and (14) shown below: 1.45 < N1nave < 2.3 (13) 16 < v1nave < 85 (14).

16. The imaging lens according to claim 1 or 2, wherein when the combined focal length of all the lenses on the object side of the diaphragm in a state of focusing on an infinitely distant object is set as fGf, and the combined focal length of all the lenses on the image side of the diaphragm in a state of focusing on an infinitely distant object is set as fGr, the imaging lens satisfies the conditional expression (15) shown below: -10 < fGf / fGr < 31 (15).

17. The imaging lens according to claim 1 or 2, wherein the lens surface closest to the image side of the second lens group is a convex shape.

18. The imaging lens according to claim 1 or 2, wherein the imaging lens includes at least one lens surface having an inflection point, when the distance on the optical axis from the lens surface closest to the object side of the first lens group to the lens surface closest to the image side of the third lens group is set as DL, in a state of focusing on an infinitely distant object, at least one of the intersections of the lens surface having the inflection point and the optical axis is a specific intersection, and the specific intersection is within the range of 0.3×DL toward the image side from the intersection of the lens surface closest to the object side of the first lens group and the optical axis, or within the range of 0.3×DL toward the object side from the intersection of the lens surface closest to the image side of the third lens group and the optical axis.

19. The imaging lens according to claim 18, wherein when the refractive power of the lens surface having the specific intersection is set as φa, and the refractive power of the imaging lens in a state of focusing on an infinitely distant object is set as φ, at least one of the lens surfaces having the specific intersection satisfies the conditional expression (16) shown below: -2 < φa / φ < 3 (16).

20. An imaging device including the imaging lens according to any one of claims 1 to 19.

Images