Wide-angle lens

Abstract

A wide-angle lens which can easily avoid the length of the entire lens system from becoming too long while ensuring optical performance. The wide-angle lens of the present invention includes, in order from the object side, a first lens, a second lens, a third lens, a fourth lens, an aperture, a fifth lens, a sixth lens, and a seventh lens, and when the object-image distance of the wide-angle lens is set as d and the entrance pupil diameter of the wide-angle lens is set as HEP, the following relationship is satisfied: d / HEP < 29.000.

Description

TECHNICAL FIELD

[0001] The present application relates to a wide-angle lens. BACKGROUND

[0002] As a wide-angle lens for a vehicle-mounted camera, there has been a wide-angle lens including, in order from an object side, a first lens, a second lens, a third lens, a fourth lens, an aperture, a fifth lens, a sixth lens, and a seventh lens (for example, refer to Patent Document 1).

[0003] Patent Document 1: Japanese Patent Laid-Open No. 2018-60153

[0004] In practice, sometimes the space for mounting the above-described wide-angle lens on a vehicle is limited in length in the optical axis direction of the wide-angle lens, and thus it is desirable to avoid the overall length of the wide-angle lens from becoming excessively long while ensuring the optical performance of the wide-angle lens. SUMMARY

[0005] The present application has been achieved in view of the above-described problems, and aims to provide a wide-angle lens that easily avoids the overall length of the lens system from becoming excessively long while ensuring the optical performance.

[0006] To achieve the above-described object, the present application provides a wide-angle lens including, in order from an object side, a first lens, a second lens, a third lens, a fourth lens, an aperture, a fifth lens, a sixth lens, and a seventh lens, and when an object-image distance of the wide-angle lens is set as d and an entrance pupil diameter of the wide-angle lens is set as HEP, the following relationship is satisfied: d / HEP < 29.000.

[0007] The wide-angle lens according to the present application satisfies the relationship d / HEP < 29.000 when an object-image distance of the wide-angle lens is set as d and an entrance pupil diameter of the wide-angle lens is set as HEP, and thus it is easy to avoid the overall length of the lens system from becoming excessively long while ensuring the optical performance.

[0008] Further, in the wide-angle lens of the present application, it is preferable to satisfy the following relationship: d / HEP < 27.000.

[0009] The wide-angle lens according to the present application satisfies the relationship d / HEP < 27.000, and thus it is even easier to avoid the overall length of the lens system from becoming excessively long while ensuring the optical performance.

[0010] Further, in the wide-angle lens of the present application, it is preferable to satisfy the following relationship when a focal distance of the entire wide-angle lens is set as f: 11.000 < d / f < 15.000.

[0011] The wide-angle lens according to the present application satisfies the relation d / f > 11.000 when the focal length of the entire wide-angle lens is set as f, and thus, various aberrations are easily corrected appropriately, and thus, excellent optical characteristics are easily obtained. On the other hand, the wide-angle lens according to the present application satisfies the relation d / f < 15.000 when the focal length of the entire wide-angle lens is set as f, and thus, the lens system is prevented from becoming too long, and the lens system is prevented from becoming too large.

[0012] Further, in the wide-angle lens according to the present application, it is preferable that the wide-angle lens satisfy the relation f / HEP < 2.3 when the focal length of the entire wide-angle lens is set as f.

[0013] The wide-angle lens according to the present application satisfies the relation f / HEP < 2.3 when the focal length of the entire wide-angle lens is set as f, and thus, the brightness is ensured, and thus, the wide-angle lens can be applied to a high-density imaging device.

[0014] Further, in the wide-angle lens according to the present application, it is preferable that the sixth lens and the seventh lens constitute a cemented lens, the first lens be a negative lens having a concave surface toward the image side, the second lens be a negative lens having a concave surface toward the image side, the third lens be a positive lens having a convex surface toward the image side, the fourth lens be a positive lens having a convex surface toward the image side, the fifth lens be a positive lens having a convex surface toward the object side and a convex surface toward the image side, the sixth lens be a negative lens having a concave surface toward the image side, the seventh lens be a positive lens having a convex surface toward the object side and a convex surface toward the image side, the combined focal length of the first lens, the second lens, the third lens, and the fourth lens be set as f1234, the combined focal length of the fifth lens, the sixth lens, and the seventh lens be set as f567, and the relation 0.800 < f1234 / f567 < 8.000 be satisfied.

[0015] In the wide-angle lens according to the present application, the sixth lens and the seventh lens constitute a cemented lens, the first lens is a negative lens with a concave surface facing the image side, the second lens is a negative lens with a concave surface facing the image side, the third lens is a positive lens with a convex surface facing the image side, the fourth lens is a positive lens with a convex surface facing the image side, the fifth lens is a positive lens with a convex surface facing the object side and a convex surface facing the image side, the sixth lens is a negative lens with a concave surface facing the image side, and the seventh lens is a positive lens with a convex surface facing the object side and a convex surface facing the image side; and when the combined focal length of the first lens, the second lens, the third lens, and the fourth lens is set as f1234 and the combined focal length of the fifth lens, the sixth lens, and the seventh lens is set as f567, the following relationship is satisfied: f1234 / f567 > 0.800. Thus, the power of the front lens group composed of the first lens, the second lens, the third lens, and the fourth lens can be prevented from being too strong, and thus various aberrations can be appropriately corrected, and thus excellent optical characteristics can be easily obtained. On the other hand, when the combined focal length of the first lens, the second lens, the third lens, and the fourth lens is set as f1234 and the combined focal length of the fifth lens, the sixth lens, and the seventh lens is set as f567, the following relationship is satisfied: f1234 / f567 < 8.000. Thus, the power of the front lens group composed of the first lens, the second lens, the third lens, and the fourth lens can be prevented from being too weak, and thus the diameters of the lenses of the front lens group can be reduced, and thus the entire lens system can be easily downsized.

[0016] In the wide-angle lens according to the present application, the sixth lens and the seventh lens constitute a cemented lens, the first lens is a negative lens with a concave surface facing the image side, the second lens is a negative lens with a concave surface facing the image side, the third lens is a positive lens with a convex surface facing the image side, the fourth lens is a positive lens with a convex surface facing the image side, the fifth lens is a positive lens with a convex surface facing the object side and a convex surface facing the image side, the sixth lens is a negative lens with a concave surface facing the image side, and the seventh lens is a positive lens with a convex surface facing the object side and a convex surface facing the image side; and when the combined focal length of the fifth lens, the sixth lens, and the seventh lens is set as f567 and the focal length of the entire wide-angle lens is set as f, the following relationship is satisfied: 2.800 < f567 / f < 3.850.

[0017] In the wide-angle lens according to the present application, when the focal length of the entire wide-angle lens is set as f, the following relationship is satisfied: f567 / f > 2.800. Thus, the power of the rear lens group composed of the fifth lens, the sixth lens, and the seventh lens can be prevented from being too strong, and thus various aberrations, particularly chromatic aberration, can be appropriately corrected, and thus excellent optical characteristics can be easily obtained. Also, when the focal length of the entire wide-angle lens is set as f, the following relationship is satisfied: f567 / f < 3.850. Thus, the diameters of the lenses and the object-image distance can be reduced, and thus the entire wide-angle lens can be more downsized.

[0018] Further, in the wide-angle lens of the present application, the sixth lens and the seventh lens constitute a combined lens, the first lens is a negative lens with a concave surface toward the image side, the second lens is a negative lens with a concave surface toward the image side, the third lens is a positive lens with a convex surface toward the image side, the fourth lens is a positive lens with a convex surface toward the image side, the fifth lens is a positive lens with a convex surface toward the object side and a convex surface toward the image side, the sixth lens is a negative lens with a concave surface toward the image side, and the seventh lens is a positive lens with a convex surface toward the object side and a convex surface toward the image side; when the combined focal length of the fifth lens, the sixth lens, and the seventh lens is set as f567 and the focal length of the entire wide-angle lens is set as f, the relationship f567 / f > 2.800 is satisfied, and thus, it is possible to avoid excessive power of the rear lens group constituted by the fifth lens, the sixth lens, and the seventh lens, and thereby, it is easy to appropriately correct various aberrations, particularly chromatic aberration, and thus, it is easy to obtain excellent optical characteristics; on the other hand, when the focal length of the entire wide-angle lens is set as f, the relationship f567 / f < 3.850 is satisfied, and thus, it is possible to reduce the diameters of the lenses and the object-image distance, and thereby, it is possible to more easily achieve the miniaturization of the entire lens system.

[0019] (EFFECT OF INVENTION)

[0020] According to the present application, when the object-image distance of the wide-angle lens is set as d and the entrance pupil diameter of the wide-angle lens is set as HEP, the relationship d / HEP < 29.000 is satisfied, and thus, it is possible to avoid the length of the entire lens system from becoming excessively long while ensuring optical performance. BRIEF DESCRIPTION OF DRAWINGS

[0021] FIG. 1 is a diagram showing the wide-angle lens of Embodiment 1 of the present application.

[0022] FIG. 2A is a diagram showing the field curvature and distortion of the wide-angle lens of Embodiment 1 of the present application.

[0023] FIG. 2B is a diagram showing the field curvature and distortion of the wide-angle lens of Embodiment 1 of the present application.

[0024] FIG. 3A is a diagram showing the sagittal chromatic aberration (lateral chromatic aberration) of the wide-angle lens of Embodiment 1 of the present application.

[0025] FIG. 3B is a diagram showing the spherical aberration (longitudinal aberration) of the wide-angle lens of Embodiment 1 of the present application.

[0026] FIG. 4A to FIG. 4L is a diagram showing the lateral aberration of the wide-angle lens of Embodiment 1 of the present application.

[0027] FIG. 5is a diagram showing a wide-angle lens according to Embodiment 2 of the present application.

[0028] FIG. 6A is a diagram showing field curvature and distortion of a wide-angle lens according to Embodiment 2 of the present application.

[0029] FIG. 6B is a diagram showing field curvature and distortion of a wide-angle lens according to Embodiment 2 of the present application.

[0030] FIG. 7A is a diagram showing lateral chromatic aberration (transverse chromatic aberration) of a wide-angle lens according to Embodiment 2 of the present application.

[0031] FIG. 7B is a diagram showing longitudinal chromatic aberration (spherical aberration) of a wide-angle lens according to Embodiment 2 of the present application.

[0032] FIG. 8A to FIG. 8L is a diagram showing lateral chromatic aberration of a wide-angle lens according to Embodiment 2 of the present application.

[0033] FIG. 9 is a diagram showing a wide-angle lens according to Embodiment 3 of the present application.

[0034] FIG. 10A is a diagram showing field curvature and distortion of a wide-angle lens according to Embodiment 3 of the present application.

[0035] FIG. 10B is a diagram showing field curvature and distortion of a wide-angle lens according to Embodiment 3 of the present application.

[0036] FIG. 11A is a diagram showing lateral chromatic aberration (transverse chromatic aberration) of a wide-angle lens according to Embodiment 3 of the present application.

[0037] FIG. 11B is a diagram showing longitudinal chromatic aberration (spherical aberration) of a wide-angle lens according to Embodiment 3 of the present application.

[0038] FIG. 12A to FIG. 12L is a diagram showing lateral chromatic aberration of a wide-angle lens according to Embodiment 3 of the present application.

[0039] FIG. 13 is a diagram showing a wide-angle lens according to Embodiment 4 of the present application.

[0040] FIG. 14A is a diagram showing field curvature and distortion of a wide-angle lens according to Embodiment 4 of the present application.

[0041] FIG. 14B is a diagram showing field curvature and distortion of a wide-angle lens according to Embodiment 4 of the present application.

[0042] FIG. 15Ais a diagram showing the sagittal aberration (longitudinal chromatic aberration) of the wide-angle lens of Embodiment 4 of the present application.

[0043] FIG. 15B is a diagram showing the lateral chromatic aberration of the wide-angle lens of Embodiment 4 of the present application.

[0044] FIG. 16A to FIG. 16L is a diagram showing the lateral chromatic aberration of the wide-angle lens of Embodiment 4 of the present application.

[0045] FIG. 17 is a diagram showing the lateral chromatic aberration of the wide-angle lens of Embodiment 4 of the present application.

[0046] FIG. 18A is a diagram showing the lateral chromatic aberration of the wide-angle lens of Embodiment 4 of the present application.

[0047] FIG. 18B is a diagram showing the lateral chromatic aberration of the wide-angle lens of Embodiment 4 of the present application.

[0048] FIG. 19A is a diagram showing the lateral chromatic aberration of the wide-angle lens of Embodiment 4 of the present application.

[0049] FIG. 19B is a diagram showing the lateral chromatic aberration of the wide-angle lens of Embodiment 4 of the present application.

[0050] FIG. 20A to FIG. 20L is a diagram showing the lateral chromatic aberration of the wide-angle lens of Embodiment 4 of the present application.

[0051] FIG. 18A is a diagram showing the lateral chromatic aberration of the wide-angle lens of Embodiment 4 of the present application.

[0052] FIG. 18B is a diagram showing the lateral chromatic aberration of the wide-angle lens of Embodiment 4 of the present application.

[0053] FIG. 19A is a diagram showing the lateral chromatic aberration of the wide-angle lens of Embodiment 4 of the present application.

[0054] FIG. 19B is a diagram showing the lateral chromatic aberration of the wide-angle lens of Embodiment 4 of the present application.

[0055] FIG. 20A to FIG. 20L is a diagram showing the lateral chromatic aberration of the wide-angle lens of Embodiment 4 of the present application.

[0056] FIG. 20A to FIG. 20L is a diagram showing the lateral chromatic aberration of the wide-angle lens of Embodiment 4 of the present application.

[0057] FIG. 17 is a diagram showing a field curvature and distortion of the wide-angle lens according to Embodiment 7 of the present application.

[0058] FIG. 17 is a diagram showing a field curvature and distortion of the wide-angle lens according to Embodiment 7 of the present application.

[0059] FACE is a diagram showing a field curvature and distortion of the wide-angle lens according to Embodiment 7 of the present application.

[0060] FIG. 18A to FIG. 20L is a diagram showing a lateral chromatic aberration (transverse chromatic aberration) of the wide-angle lens according to Embodiment 7 of the present application.

[0061] FIG. 21 is a diagram showing a longitudinal chromatic aberration (longitudinal chromatic aberration) of the wide-angle lens according to Embodiment 7 of the present application.

[0062] FIG. 22A is a diagram showing a lateral chromatic aberration (transverse chromatic aberration) of the wide-angle lens according to Embodiment 7 of the present application.

[0063] FIG. 22B is a diagram showing a field curvature and distortion of the wide-angle lens according to Embodiment 8 of the present application.

[0064] FIG. 23A is a diagram showing a field curvature and distortion of the wide-angle lens according to Embodiment 8 of the present application.

[0065] FIG. 23B is a diagram showing a field curvature and distortion of the wide-angle lens according to Embodiment 8 of the present application.

[0066] FIG. 24A to FIG. 24L is a diagram showing a lateral chromatic aberration (transverse chromatic aberration) of the wide-angle lens according to Embodiment 8 of the present application.

[0067] FIG. 22A is a diagram showing a longitudinal chromatic aberration (longitudinal chromatic aberration) of the wide-angle lens according to Embodiment 8 of the present application.

[0068] FIG. 22B is a diagram showing a lateral chromatic aberration (transverse chromatic aberration) of the wide-angle lens according to Embodiment 8 of the present application.

[0069] FIG. 23A is a diagram showing a field curvature and distortion of the wide-angle lens according to Embodiment 9 of the present application.

[0070] FIG. 23B is a diagram showing a field curvature and distortion of the wide-angle lens according to Embodiment 9 of the present application.

[0071] FIG. 24A to FIG. 24L is a diagram showing a field curvature and distortion of the wide-angle lens according to Embodiment 9 of the present application.

[0072] FIG. 24A to FIG. 24Lis a diagram showing the sagittal aberration (longitudinal chromatic aberration) of the wide-angle lens of Embodiment 9 of the present application.

[0073] FIG. 21 is a diagram showing the lateral chromatic aberration of the wide-angle lens of Embodiment 9 of the present application.

[0074] FIG. 21 is a diagram showing the lateral chromatic aberration of the wide-angle lens of Embodiment 9 of the present application.

[0075] (Symbol explanation)

[0076] 1000 Wide-angle lens

[0077] 110 First lens

[0078] 120 Second lens

[0079] 130 Third lens

[0080] 140 Fourth lens

[0081] 150 Fifth lens

[0082] 160 Sixth lens

[0083] 170 Seventh lens

[0084] 180 Aperture

[0085] 190 Shutter

[0086] 200 Filter

[0087] 300 Imaging element DETAILED DESCRIPTION

[0088] Hereinafter, each embodiment of the wide-angle lens of the present application will be described with reference to the accompanying drawings. Also, in the following description, in the direction of extension of the optical axis L, L1 is marked on the object side, and L2 is marked on the image side.

[0089] (Embodiment 1)

[0090] FACE is a diagram showing the sagittal aberration (longitudinal chromatic aberration) of the wide-angle lens of Embodiment 9 of the present application. FIG. 22A to FIG. 24L is a diagram showing the sagittal aberration (longitudinal chromatic aberration) of the wide-angle lens of Embodiment 9 of the present application. FIG. 25 is a diagram showing the sagittal aberration (longitudinal chromatic aberration) of the wide-angle lens of Embodiment 9 of the present application. FIG. 26A is a diagram showing the sagittal aberration (longitudinal chromatic aberration) of the wide-angle lens of Embodiment 9 of the present application. FIG. 26B is a diagram showing the sagittal aberration (longitudinal chromatic aberration) of the wide-angle lens of Embodiment 9 of the present application. FIG. 27Ais an explanatory view showing the lateral aberration of the wide-angle lens of Embodiment 1 of the present application. Here, in FIG. 27B , FIG. 28A to FIG. 28L , FIG. 26A , FIG. 26B , FIG. 27A , the correlation curve for red light R (wavelength: 656 nm) is denoted by R, the correlation curve for green light G (wavelength: 588 nm) is denoted by G, the correlation curve for blue light B (wavelength: 486 nm) is denoted by B, T indicates the tangential direction, and S indicates the sagittal direction, and in FIG. 27B , the maximum scale of the vertical axis is ±50.000 μm.

[0091] As shown in FIG. 28A to FIG. 28L , the wide-angle lens 1000 includes, in order from the object side (L1 side), a first lens 110, a second lens 120, a third lens 130, a fourth lens 140, an aperture 180, a fifth lens 150, a sixth lens 160, and a seventh lens 170, wherein the sixth lens 160 and the seventh lens 170 are bonded together by an adhesive to constitute a cemented lens.

[0092] Here, the first lens 110 is a lens having a negative refractive power (referred to simply as a negative lens) in which a convex surface (first surface 1) faces the object side L1 and a concave surface (second surface 2) faces the image side L2. In the present embodiment, the first lens 110 is a glass lens in which the first surface 1 and the second surface 2 are spherical.

[0093] The second lens 120 is a lens having a negative refractive power in which a convex surface (third surface 3) faces the object side L1 and a concave surface (fourth surface 4) faces the image side L2. In the present embodiment, the second lens 120 is a plastic lens in which the third surface 3 and the fourth surface 4 are aspherical.

[0094] The third lens 130 is a lens having a positive refractive power (referred to simply as a positive lens) in which a concave surface (fifth surface 5) faces the object side L1 and a convex surface (sixth surface 6) faces the image side L2. In the present embodiment, the third lens 130 is a plastic lens in which the fifth surface 5 and the sixth surface 6 are aspherical.

[0095] The fourth lens 140 is a lens having a positive refractive power in which a concave surface (seventh surface 7) faces the object side L1 and a convex surface (eighth surface 8) faces the image side L2. In the present embodiment, the fourth lens 140 is a plastic lens in which the seventh surface 7 and the eighth surface 8 are aspherical.

[0096] The fifth lens 150 is a lens having a positive refractive power in which a convex surface (tenth surface 10) faces the object side L1 and a convex surface (eleventh surface 11) faces the image side L2. In the present embodiment, the fifth lens 150 is constituted by a glass lens.

[0097] The sixth lens 160 is a lens having negative refractive power with a concave surface (twelfth surface 12) toward the object side LI and a concave surface (thirteenth surface 13) toward the image side L2, and constitutes a cemented lens with the seventh lens 170. In the present embodiment, the sixth lens 160 is a plastic lens with the twelfth surface 12 and the thirteenth surface 13 being aspherical surfaces.

[0098] The seventh lens 170 is a lens having positive refractive power with a convex surface (thirteenth surface 13) toward the object side LI and a convex surface (fourteenth surface 14) toward the image side L2. In the present embodiment, the seventh lens 170 is a plastic lens with the thirteenth surface 13 and the fourteenth surface 14 being aspherical surfaces.

[0099] Further, in the present embodiment, as shown in FIG. 1, a light shield 190 is provided between the second lens 120 and the fourth lens 130, a filter 200 is disposed on the image side of the seventh lens 170, and an image pickup element 300 is disposed on the image side of the filter 200. FIG. 28A to FIG. 28L

[0100] In the present embodiment, the effective focal length f of the entire lens system is 1.023 mm, the total track d is 13.611 mm, the image space F / # is 2.02, the maximum field of angle is 115 degrees, and the entrance pupil diameter HEP is 0.507 mm.

[0101] The physical properties of each surface of the wide-angle lens 1000 of the present embodiment are shown in Table 1, and the aspherical coefficients of each surface of the wide-angle lens 1000 of the present embodiment are shown in Table 2-1 and Table 2-2.

[0102] (Table 1)

[0103]

[0104] In Table 1 above, the units of the radius of curvature, the thickness, and the effective focal length are mm, Nd is the refractive index for a light ray of 587.56 nm, νd is the Abbe number, and * indicates an aspherical surface.

[0105] (Table 2-1)

[0106]

[0107] (Table 2-2)

[0108] FIG. 25 A8 A10 A12 A14 A16 3 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 4 -3.29328E-03 2.82298E-03 -4.88754E-04 0.00000E+00 0.00000E+00 5 -5.12306E-03 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 6 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 7 4.37857E-03 2.92148E-03 0.00000E+00 0.00000E+00 0.00000E+00 8 -5.94177E-03 1.11565E-02 0.00000E+00 0.00000E+00 0.00000E+00 12 1.79956E-02 -7.87537E-04 -1.30556E-03 0.00000E+00 0.00000E+00 13 1.73181E-01 -4.77496E-02 4.65741E-03 0.00000E+00 0.00000E+00 14 1.34046E-02 -4.35536E-03 5.73510E-04 0.00000E+00 0.00000E+00

[0109] ​In Tables 2-1 and 2-2 above, the curvature radius is set to a positive value in the case where the lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, and is set to a negative value in the case where the lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side.

[0110] Further, in Tables 2-1 and 2-2 above, aspherical coefficients A4, A6, A8, A10, A12, A14, A16 at the time of expressing the aspherical shape of each surface by the following equation (Mathematical Formula 1) are shown. In the following equation, the sag amount (axial direction of the optical axis) is set to Z, the height in the direction perpendicular to the optical axis (height of the light ray) is set to r, the conic coefficient is set to K, and the reciprocal of the curvature radius is set to c.

[0111] [Mathematical Formula 1]

[0112]

[0113] Here, in the wide-angle lens 1000, the object-image distance d is 13.611 mm, and the entrance pupil diameter HEP is 0.507 mm, and thus the following condition 1 is satisfied:

[0114] d / HEP < 29.000

[0115] In the condition 1, if d / HEP is 29.000 or more, it is not easy to avoid the length of the entire lens system from becoming excessively long while securing the optical performance.

[0116] On the contrary, in the present embodiment, since the condition 1 is satisfied, it is easy to avoid the length of the entire lens system from becoming excessively long while securing the optical performance.

[0117] In particular, in the present embodiment, since the relationship of d / HEP < 27.000 is satisfied, it is even easier to avoid the length of the entire lens system from becoming excessively long while securing the optical performance.

[0118] Further, in the wide-angle lens 1000, the object-image distance d is 13.611 mm, and the focal distance f of the entire lens system is 1.023 mm, and thus the following condition 2 is satisfied:

[0119] 11.000 < d / f < 15.000

[0120] In the condition 2, if d / f is 11.000 or less, it is not easy to appropriately correct various aberrations, and on the other hand, if d / f is 15.000 or more, the length of the entire lens system becomes excessively long.

[0121] On the contrary, in the present embodiment, since the condition 2 is satisfied, it is easy to appropriately correct various aberrations, it is easy to obtain excellent optical characteristics, and it is possible to suppress the lens system from becoming too large while avoiding the length of the entire lens system from becoming too long.

[0122] Further, in the wide-angle lens 1000, the focal length f of the entire lens system is 1.023 mm, and the entrance pupil diameter HEP is 0.507 mm, and thus the following condition 3 is satisfied:

[0123] f / HEP < 2.3

[0124] In the condition 3, if f / HEP is 2.3 or more, it is not easy to secure the brightness.

[0125] On the contrary, in the present embodiment, since the condition 3 is satisfied, it is possible to secure the brightness, and thus it is possible to be applied to a high-density imaging device.

[0126] Further, in the wide-angle lens 1000, the combined focal length f1234 of the first lens 110, the second lens 120, the third lens 130, and the fourth lens 140 is 3.148 mm, and the combined focal length f567 of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.740 mm, and thus the following condition 4 is satisfied:

[0127] 0.800 < f1234 / f567 < 8.000

[0128] In the condition 4, if f1234 / f567 is 0.800 or less, the power of the front lens group composed of the first lens, the second lens, the third lens, and the fourth lens is too strong, it is not easy to appropriately correct various aberrations, on the other hand, if f1234 / f567 is 8.000 or more, the power of the front lens group composed of the first lens, the second lens, the third lens, and the fourth lens is too weak, it is not easy to reduce the diameter of each lens of the front lens group, and it is not easy to achieve the miniaturization of the entire wide-angle lens.

[0129] On the contrary, in the present embodiment, since the condition 4 is satisfied, it has the advantages that it is easy to appropriately correct various aberrations and it is easy to achieve miniaturization.

[0130] Further, in the wide-angle lens 1000, the combined focal length f567 of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.740 mm, and the focal length f of the entire lens system is 1.023 mm, and thus the following condition 5 is satisfied:

[0131] 2.800 < f567 / f < 3.850.

[0132] In condition 5, if f567 / f is below 2.800, the optical focal length of the rear lens group consisting of the fifth, sixth, and seventh lenses will be too strong, making it difficult to properly correct various aberrations, especially chromatic aberration. On the other hand, if f567 / f is above 3.850, it will be difficult to reduce the diameter of each lens and the distance between the object and the image, making it difficult to achieve overall miniaturization of the wide-angle lens.

[0133] In contrast, in this embodiment, since condition 5 is satisfied, it has the advantages of being able to easily correct various aberrations, especially chromatic aberrations, and being easier to miniaturize.

[0134] In summary, in this embodiment, by constructing the wide-angle lens 1000 in the manner described above, as follows... FIG. 25 As shown, it is easy to ensure optical performance while avoiding the overall length of the lens system becoming too long.

[0135] (Implementation Method 2)

[0136] FACE This is an explanatory diagram showing the wide-angle lens according to Embodiment 2 of the present invention. FIG. 26A to FIG. 28L This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 2 of the present invention. FIG. 29 This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 2 of the present invention. FIG. 30A This is an explanatory diagram showing the transverse chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to Embodiment 2 of the present invention. FIG. 30B This is an explanatory diagram showing the spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 2 of the present invention. FIG. 31A This is an explanatory diagram illustrating the lateral aberration of the wide-angle lens according to Embodiment 2 of the present invention. Here, in FIG. 31B , FIG. 32A to FIG. 32L , FIG. 30A , FIG. 30B , FIG. 31A In the diagram, the correlation curve for red light R (wavelength 656 nm) is labeled R, the correlation curve for green light G (wavelength 588 nm) is labeled G, and the correlation curve for blue light B (wavelength 486 nm) is labeled B. T represents correlation with the meridional plane, and S represents correlation with the sagittal plane. Furthermore, in... FIG. 31B In the figure, the maximum scale of the vertical axis is ±50.000 μm.

[0137] like FIG. 32A to FIG. 32L As shown, the wide-angle lens 1000 includes a first lens 110, a second lens 120, a third lens 130, a fourth lens 140, an aperture 180, a fifth lens 150, a sixth lens 160, and a seventh lens 170 arranged sequentially from the object side (L1 side). The sixth lens 160 and the seventh lens 170 are bonded together with an adhesive to form a joint lens.

[0138] In this embodiment, since the basic structure of the wide-angle lens 1000 (i.e., whether the first lens 110, the second lens 120, the third lens 130, the fourth lens 140, the fifth lens 150, the sixth lens 160, and the seventh lens 170 have positive or negative refractive power, are glass or plastic lenses, the object-side surface and the image-side surface are convex or concave, and are spherical or aspherical) is the same as that of the wide-angle lens in Embodiment 1, detailed description thereof will not be repeated here.

[0139] Further, as shown in FIG. 1, like Embodiment 1, a light-shielding sheet 190 is provided between the second lens 120 and the fourth lens 130, a filter 200 is disposed on the image side of the seventh lens 170, and an image pickup element 300 is disposed on the image side of the filter 200. FIG. 24A to FIG. 24L

[0140] In this embodiment, the effective focal length f of the entire lens system is 1.062 mm, the total track d is 13.610 mm, the image space F / # is 2.02, the maximum field of angle is 115 degrees, and the entrance pupil diameter HEP is 0.526 mm.

[0141] The physical properties of each surface of the wide-angle lens 1000 of this embodiment are shown in Table 3, and the aspherical coefficients of each surface of the wide-angle lens 1000 of this embodiment are shown in Table 4-1 and Table 4-2.

[0142] (Table 3)

[0143]

[0144] In Table 3 above, the units of the radius of curvature, the thickness, and the effective focal length are mm, Nd is the refractive index for a light ray of 587.56 nm, νd is the Abbe number, and * indicates that it is an aspherical surface.

[0145] (Table 4-1)

[0146]

[0147] (Table 4-2)

[0148] FIG. 29 A8 A10 A12 A14 A16 3 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 4 1.18832E-02 -3.21383E-03 7.23623E-04 0.00000E+00 0.00000E+00 5 -7.11892E-03 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 6 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 7 1.48329E-02 -9.20347E-04 0.00000E+00 0.00000E+00 0.00000E+00 8 3.16264E-03 4.17741E-03 0.00000E+00 0.00000E+00 0.00000E+00 12 -7.44565E-04 -1.42901E-03 0.00000E+00 0.00000E+00 0.00000E+00 13 1.80337E-01 -4.80759E-02 4.57265E-03 0.00000E+00 0.00000E+00 14 1.50208E-02 -4.69107E-03 5.90742E-04 0.00000E+00 0.00000E+00

[0149] ​In Tables 4-1 and 4-2 above, the curvature radius is set to a positive value in the case where the lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, and is set to a negative value in the case where the lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side.

[0150] Further, in Tables 4-1 and 4-2 above, the aspheric coefficients A4, A6, A8, A10, A12, A14, and A16 at the time of expressing the aspheric shape of each surface by the above Mathematical Formula 1 are shown.

[0151] Here, in the wide-angle lens 1000, the object-image distance d is 13.610 mm, and the entrance pupil diameter HEP is 0.526 mm, and thus the following Condition 1 is satisfied:

[0152] d / HEP < 29.000

[0153] In Condition 1, if d / HEP is 29.000 or more, it is not easy to avoid the length of the entire lens system from becoming excessively long while securing optical performance.

[0154] On the contrary, in the present embodiment, since Condition 1 is satisfied, it is easy to avoid the length of the entire lens system from becoming excessively long while securing optical performance.

[0155] In particular, in the present embodiment, since the relationship of d / HEP < 27.000 is satisfied, it is even easier to avoid the length of the entire lens system from becoming excessively long while securing optical performance.

[0156] Further, in the wide-angle lens 1000, the object-image distance d is 13.610 mm, and the focal distance f of the entire lens system is 1.062 mm, and thus the following Condition 2 is satisfied:

[0157] 11.000 < d / f < 15.000

[0158] In Condition 2, if d / f is 11.000 or less, it is not easy to appropriately correct various aberrations, and on the other hand, if d / f is 15.000 or more, the length of the entire lens system becomes excessively long.

[0159] On the contrary, in the present embodiment, since Condition 2 is satisfied, it is easy to appropriately correct various aberrations, it is easy to obtain excellent optical characteristics, and it is possible to suppress the entire lens system from becoming excessively large while avoiding the length of the entire lens system from becoming excessively long.

[0160] Further, in the wide-angle lens 1000, the focal distance f of the entire lens system is 1.062 mm, and the entrance pupil diameter HEP is 0.526 mm, and thus the following Condition 3 is satisfied:

[0161] f / HEP < 2.3

[0162] In the condition 3, if f / HEP is 2.3 or more, it is difficult to secure the brightness.

[0163] On the contrary, in the present embodiment, since the condition 3 is satisfied, the brightness can be secured, and thus the imaging device can be applied to high densification.

[0164] Further, in the wide-angle lens 1000, the combined focal distance f1234 of the first lens 110, the second lens 120, the third lens 130, and the fourth lens 140 is 4.237 mm, and the combined focal distance f567 of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.640 mm, and thus the following condition 4 is satisfied:

[0165] 0.800 < f1234 / f567 < 8.000

[0166] In the condition 4, if f1234 / f567 is 0.800 or less, the power of the front lens group composed of the first lens, the second lens, the third lens, and the fourth lens is too strong, and it is difficult to appropriately correct various aberrations, and on the other hand, if f1234 / f567 is 8.000 or more, the power of the front lens group composed of the first lens, the second lens, the third lens, and the fourth lens is too weak, and it is difficult to reduce the diameter of each lens of the front lens group, and it is difficult to achieve the miniaturization of the entire wide-angle lens.

[0167] On the contrary, in the present embodiment, since the condition 4 is satisfied, it has the advantages that it is easy to appropriately correct various aberrations and easy to achieve miniaturization.

[0168] Further, in the wide-angle lens 1000, the combined focal distance f567 of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.640 mm, and the focal distance f of the entire lens system is 1.062 mm, and thus the following condition 5 is satisfied:

[0169] 2.800 < f567 / f < 3.850.

[0170] In the condition 5, if f567 / f is 2.800 or less, the power of the rear lens group composed of the fifth lens, the sixth lens, and the seventh lens is too strong, and it is difficult to appropriately correct various aberrations, particularly chromatic aberration, and on the other hand, if f567 / f is 3.850 or more, it is difficult to reduce the diameter of each lens and the object-image distance, and it is difficult to achieve the miniaturization of the entire wide-angle lens.

[0171] On the contrary, in the present embodiment, since the condition 5 is satisfied, it has the advantages that it is easy to appropriately correct various aberrations, particularly chromatic aberration, and it is easier to achieve miniaturization.

[0172] As described above, in the present embodiment, by configuring the wide-angle lens 1000 in the above-described manner, it is possible to easily avoid the length of the entire lens system from becoming excessively long while ensuring optical performance, as shown in FIG. 10. FIG. 29

[0173] (Embodiment 3)

[0174] FACE FIG. 10 is a diagram showing a wide-angle lens according to Embodiment 3 of the present application, c (1 / radius of curvature) FIG. 11 is a diagram showing field curvature and distortion of the wide-angle lens according to Embodiment 3 of the present application, FACE FIG. 12 is a diagram showing field curvature and distortion of the wide-angle lens according to Embodiment 3 of the present application, FIG. 30A to FIG. 32L FIG. 13 is a diagram showing the axial chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to Embodiment 3 of the present application, FIG. 33 FIG. 14 is a diagram showing the spherical aberration (longitudinal chromatic aberration) of the wide-angle lens according to Embodiment 3 of the present application, FIG. 34A FIG. 15 is a diagram showing the lateral chromatic aberration of the wide-angle lens according to Embodiment 3 of the present application. Here, in FIG. 34B FIG. 35A FIG. 35B FIG. 36A to FIG. 36L FIG. 34A In FIGS. 13 to 15, the relevant curve for red light R (wavelength: 656 nm) is labeled R, the relevant curve for green light G (wavelength: 588 nm) is labeled G, the relevant curve for blue light B (wavelength: 486 nm) is labeled B, T indicates the tangential direction, and S indicates the sagittal direction. FIG. 34B

[0175] As shown in FIG. 10, the wide-angle lens 1000 includes, in order from the object side (L1 side), a first lens 110, a second lens 120, a third lens 130, a fourth lens 140, an aperture 180, a fifth lens 150, a sixth lens 160, and a seventh lens 170, wherein the sixth lens 160 and the seventh lens 170 are bonded together by an adhesive to constitute a bonded lens. FIG. 35A

[0176] Here, since the basic structure of the wide-angle lens 1000 in the present embodiment (i.e., whether the first lens 110, the second lens 120, the third lens 130, the fourth lens 140, the fifth lens 150, the sixth lens 160, and the seventh lens 170 have positive or negative refractive power, are glass or plastic lenses, whether the object-side surface and the image-side surface are convex or concave, and whether they are spherical or aspherical) is the same as that of the wide-angle lens in Embodiment 1, further detailed explanation is not given here.

[0177] ​​​​​​​Further, as FIG. 35B As shown in FIG. 1, the wide-angle lens 1000 according to the present embodiment includes a first lens 110, a second lens 120, a third lens 130, a fourth lens 140, a fifth lens 150, a sixth lens 160, a seventh lens 170, an eighth lens 180, a ninth lens 190, and a tenth lens 200. The first lens 110 is a positive lens having a convex surface on the object side. The second lens 120 is a negative lens having a concave surface on the image side. The third lens 130 is a positive lens having a convex surface on the image side. The fourth lens 140 is a positive lens having a convex surface on the object side. The fifth lens 150 is a negative lens having a concave surface on the image side. The sixth lens 160 is a positive lens having a convex surface on the image side. The seventh lens 170 is a positive lens having a convex surface on the object side. The eighth lens 180 is a negative lens having a concave surface on the image side. The ninth lens 190 is a positive lens having a convex surface on the image side. The tenth lens 200 is a positive lens having a convex surface on the object side.

[0178] In the present embodiment, the focal length f (Effective Focal Length) of the entire lens system is 1.026 mm, the object-image distance d (Total Track) is 13.403 mm, the F value (Image Space F / #) is 2.02, the maximum half field angle (Max. Field of Angle) is 109 degrees, and the entrance pupil diameter HEP is 0.508 mm.

[0179] The physical properties of each surface of the wide-angle lens 1000 according to the present embodiment are shown in Table 5, and the aspheric coefficients of each surface of the wide-angle lens 1000 according to the present embodiment are shown in Table 6-1 and Table 6-2.

[0180] (Table 5)

[0181]

[0182] In Table 5 above, the units of the radius of curvature, the thickness, and the focal length are mm, Nd is the refractive index for a light ray of 587.56 nm, νd is the Abbe number, and * indicates an aspheric surface.

[0183] (Table 6-1)

[0184]

[0185] (Table 6-2)

[0186] FIG. 36A to FIG. 36L A8 A10 A12 A14 A16 3 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 4 -1.08170E-02 3.74135E-03 0.00000E+00 0.00000E+00 0.00000E+00 5 -6.95368E-04 2.73435E-05 0.00000E+00 0.00000E+00 0.00000E+00 6 2.29705E-03 -1.23857E-05 0.00000E+00 0.00000E+00 0.00000E+00 7 8.85677E-03 -7.73714E-05 0.00000E+00 0.00000E+00 0.00000E+00 8 4.43504E-03 9.66329E-04 0.00000E+00 0.00000E+00 0.00000E+00 12 3.37862E-04 9.82658E-03 -3.53648E-03 -1.65685E-04 0.00000E+00 13 1.49413E-01 -7.49877E-02 2.96657E-02 -5.71297E-03 0.00000E+00 14 5.78846E-02 -2.66940E-02 6.28648E-03 -5.86821E-04 0.00000E+00

[0187] In Table 6-1 and Table 6-2 above, the radius of curvature is set to a positive value in the case where the lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, and the radius of curvature is set to a negative value in the case where the lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side.

[0188] Further, in Table 6-1 and Table 6-2 above, the aspheric coefficients A4, A6, A8, A10, A12, A14, and A16 at the time of expressing the aspheric shape of each surface by the above mathematical expression 1 are shown.

[0189] Here, in the wide-angle lens 1000, the object-image distance d is 13.403 mm, and the entrance pupil diameter HEP is 0.508 mm, and thus the following condition 1 is satisfied:

[0190] d / HEP < 29.000

[0191] In the condition 1, if d / HEP is 29.000 or more, it is not easy to avoid the length of the entire lens system from becoming too long while securing optical performance.

[0192] On the contrary, in the present embodiment, since the condition 1 is satisfied, it is easy to avoid the length of the entire lens system from becoming too long while securing optical performance.

[0193] In particular, in the present embodiment, since the relation of d / HEP < 27.000 is satisfied, it is easier to avoid the length of the entire lens system from becoming too long while securing optical performance.

[0194] Further, in the wide-angle lens 1000, the object-image distance d is 13.403 mm, and the focal distance f of the entire lens system is 1.026 mm, and thus the following condition 2 is satisfied:

[0195] 11.000 < d / f < 15.000

[0196] In the condition 2, if d / f is 11.000 or less, it is not easy to properly correct various aberrations, and on the other hand, if d / f is 15.000 or more, the length of the entire lens system becomes too long.

[0197] On the contrary, in the present embodiment, since the condition 2 is satisfied, it is easy to properly correct various aberrations, it is easy to obtain excellent optical characteristics, and it is possible to suppress the entire lens system from becoming too large while avoiding the length of the entire lens system from becoming too long.

[0198] Further, in the wide-angle lens 1000, the focal distance f of the entire lens system is 1.026 mm, and the incident pupil diameter HEP is 0.508 mm, and thus the following condition 3 is satisfied:

[0199] f / HEP < 2.3

[0200] In the condition 3, if f / HEP is 2.3 or more, it is not easy to secure brightness.

[0201] On the contrary, in the present embodiment, since the condition 3 is satisfied, it is possible to secure brightness, and thus it is possible to be applied to a high-density imaging element.

[0202] Further, in the wide-angle lens 1000, the combined focal distance f1234 of the first lens 110, the second lens 120, the third lens 130, and the fourth lens 140 is 3.572 mm, and the combined focal distance f567 of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.663 mm, and thus the following condition 4 is satisfied:

[0203] 0.800 < f1234 / f567 < 8.000

[0204] In the condition 4, if f1234 / f567 is 0.800 or less, the power of the front lens group composed of the first lens, the second lens, the third lens, and the fourth lens is too strong, and it is difficult to appropriately correct various aberrations. On the other hand, if f1234 / f567 is 8.000 or more, the power of the front lens group composed of the first lens, the second lens, the third lens, and the fourth lens is too weak, and it is difficult to reduce the diameter of each lens of the front lens group and to achieve the miniaturization of the wide-angle lens as a whole.

[0205] On the contrary, in the present embodiment, since the condition 4 is satisfied, it has the advantages that it is easy to appropriately correct various aberrations and to achieve the miniaturization.

[0206] Further, in the wide-angle lens 1000, the composite focal length f567 of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.663 mm, and the focal length f of the lens system as a whole is 1.026 mm, and thus the following condition 5 is satisfied:

[0207] 2.800 < f567 / f < 3.850.

[0208] In the condition 5, if f567 / f is 2.800 or less, the power of the rear lens group composed of the fifth lens, the sixth lens, and the seventh lens is too strong, and it is difficult to appropriately correct various aberrations, particularly chromatic aberration. On the other hand, if f567 / f is 3.850 or more, it is difficult to reduce the diameter of each lens and the object-image distance, and to achieve the miniaturization of the wide-angle lens as a whole.

[0209] On the contrary, in the present embodiment, since the condition 5 is satisfied, it has the advantages that it is easy to appropriately correct various aberrations, particularly chromatic aberration, and to achieve the miniaturization more easily.

[0210] As described above, in the present embodiment, by constituting the wide-angle lens 1000 in the above-described manner, as shown in FIG. 17, it is easy to avoid the length of the lens system as a whole from becoming too long while ensuring the optical performance. FIG. 28A to FIG. 28L

[0211] (Embodiment 4)

[0212] FIG. 33 FIG. 16 is a view showing the wide-angle lens according to Embodiment 4 of the present application, FIG. 33 FIG. 17 is a view showing the field curvature and the distortion of the wide-angle lens according to Embodiment 4 of the present application, FACE FIG. 18 is a view showing the field curvature and the distortion of the wide-angle lens according to Embodiment 4 of the present application, FIG. 34A to FIG. 36L ​is a graph showing the lateral chromatic aberration (transverse chromatic aberration) of the wide-angle lens of Embodiment 4 of the present application, ​ is a graph showing the longitudinal chromatic aberration (longitudinal chromatic aberration) of the wide-angle lens of Embodiment 4 of the present application, ​ is a graph showing the lateral chromatic aberration of the wide-angle lens of Embodiment 4 of the present application. Here, in ​ , ​ , ​ , ​ , ​ , the relevant curve for red light R (wavelength 656 nm) is labeled R, the relevant curve for green light G (wavelength 588 nm) is labeled G, the relevant curve for blue light B (wavelength 486 nm) is labeled B, T indicates the meridional plane, S indicates the sagittal plane, and in ​ , the maximum scale of the vertical axis is ±50.000 μm.

[0213] As shown in ​ , the wide-angle lens 1000 includes, in order from the object side (L1 side), a first lens 110, a second lens 120, a third lens 130, a fourth lens 140, an aperture 180, a fifth lens 150, a sixth lens 160, and a seventh lens 170, wherein the sixth lens 160 and the seventh lens 170 are bonded together by an adhesive to form a bonded lens.

[0214] Here, since the basic structure of the wide-angle lens 1000 in this embodiment (i.e., whether the first lens 110, the second lens 120, the third lens 130, the fourth lens 140, the fifth lens 150, the sixth lens 160, and the seventh lens 170 have positive or negative refractive power, are glass or plastic lenses, whether the object side surface and the image side surface are convex or concave, and whether they are spherical or aspherical) is the same as that of the wide-angle lens in Embodiment 1, it will not be described in detail here.

[0215] Further, as shown in ​ , as in Embodiment 1, a light shield 190 is provided between the second lens 120 and the fourth lens 130, a filter 200 is disposed on the image side of the seventh lens 170, and an image pickup element 300 is disposed on the image side of the filter 200.

[0216] In this embodiment, the effective focal length f of the entire lens system is 1.011 mm, the total track d is 13.404 mm, the image space F / # is 2.03, the maximum field of angle is 109 degrees, and the entrance pupil diameter HEP is 0.498 mm.

[0217] The physical properties of each surface of the wide-angle lens 1000 of the present embodiment are shown in Table 7, and the aspheric coefficients of each surface of the wide-angle lens 1000 of the present embodiment are shown in Table 8-1 and Table 8-2.

[0218] (Table 7)

[0219]

[0220] In Table 7 above, the units of the radius of curvature, the thickness, and the focal distance are mm, Nd is the refractive index for a light ray of 587.56 nm, νd is the Abbe number, and * indicates an aspheric surface.

[0221] (Table 8-1)

[0222]

[0223] (Table 8-2)

[0224] ​ A8 A10 A12 A14 A16 3 -1.15147E-03 1.50789E-04 -7.30801E-06 0.00000E+00 0.00000E+00 4 7.01048E-02 -7.98133E-03 -4.17335E-03 0.00000E+00 0.00000E+00 5 1.21716E-02 -8.91664E-03 0.00000E+00 0.00000E+00 0.00000E+00 6 2.05279E-02 -2.11693E-02 5.41203E-03 0.00000E+00 0.00000E+00 7 6.15517E-03 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 8 8.49340E-03 3.83965E-03 -2.61241E-03 0.00000E+00 0.00000E+00 12 -5.25642E-02 5.03801E-02 -2.60337E-02 5.67639E-03 0.00000E+00 13 1.93193E-02 -2.02628E-02 1.27147E-02 -3.03203E-03 0.00000E+00 14 5.37377E-02 -2.41958E-02 5.72598E-03 -5.29799E-04 0.00000E+00

[0225] In Table 8-1 and Table 8-2 above, the radius of curvature is set to a positive value in the case where the lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, and the radius of curvature is set to a negative value in the case where the lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side.

[0226] Further, in Table 8-1 and Table 8-2 above, the aspheric coefficients A4, A6, A8, A10, A12, A14, and A16 at the time of expressing the aspheric shape of each surface by the above mathematical expression 1 are shown.

[0227] Here, in the wide-angle lens 1000, the object-image distance d is 13.404 mm, and the entrance pupil diameter HEP is 0.498 mm, and thus the following condition 1 is satisfied:

[0228] d / HEP < 29.000

[0229] In condition 1, if d / HEP is 29.000 or more, it is not easy to avoid the length of the entire lens system from becoming excessively long while ensuring optical performance.

[0230] On the contrary, in the present embodiment, since condition 1 is satisfied, it is easy to avoid the length of the entire lens system from becoming excessively long while ensuring optical performance.

[0231] In particular, in the present embodiment, since the relationship d / HEP < 27.000 is satisfied, it is even easier to avoid the length of the entire lens system from becoming excessively long while ensuring optical performance.

[0232] Further, in the wide-angle lens 1000, the object-image distance d is 13.404 mm, and the focal distance f of the entire lens system is 1.011 mm, and thus the following condition 2 is satisfied:

[0233] 11.000 < d / f < 15.000

[0234] In the condition 2, if d / f is 11.000 or less, it is not easy to appropriately correct various aberrations, and on the other hand, if d / f is 15.000 or more, the length of the entire lens system becomes too long.

[0235] On the contrary, in the present embodiment, since the condition 2 is satisfied, it is easy to appropriately correct various aberrations, it is easy to obtain excellent optical characteristics, and it is possible to suppress the entire lens system from becoming too large while avoiding the length of the entire lens system from becoming too long.

[0236] Further, in the wide-angle lens 1000, the focal distance f of the entire lens system is 1.011 mm, and the incident pupil diameter HEP is 0.498 mm, and thus the following condition 3 is satisfied:

[0237] f / HEP < 2.3

[0238] In the condition 3, if f / HEP is 2.3 or more, it is not easy to secure the brightness.

[0239] On the contrary, in the present embodiment, since the condition 3 is satisfied, it is possible to secure the brightness, and thus it is possible to be applied to a high-density imaging element.

[0240] Further, in the wide-angle lens 1000, the combined focal distance f1234 of the first lens 110, the second lens 120, the third lens 130, and the fourth lens 140 is 6.571 mm, and the combined focal distance f567 of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.355 mm, and thus the following condition 4 is satisfied:

[0241] 0.800 < f1234 / f567 < 8.000

[0242] In the condition 4, if f1234 / f567 is 0.800 or less, the power of the front lens group composed of the first lens, the second lens, the third lens, and the fourth lens is too strong, it is not easy to appropriately correct various aberrations, and on the other hand, if f1234 / f567 is 8.000 or more, the power of the front lens group composed of the first lens, the second lens, the third lens, and the fourth lens is too weak, it is not easy to reduce the diameter of each lens of the front lens group, and it is not easy to achieve the miniaturization of the entire wide-angle lens.

[0243] On the contrary, in the present embodiment, since the condition 4 is satisfied, there are advantages that various aberrations are easily and appropriately corrected and miniaturization is easily achieved.

[0244] Further, in the wide-angle lens 1000, the composite focal length f567 of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.355 mm, and the focal length f of the entire lens system is 1.011 mm, and thus the following condition 5 is satisfied:

[0245] 2.800 < f567 / f < 3.850.

[0246] In the condition 5, if f567 / f is 2.800 or less, the power of the rear lens group composed of the fifth lens, the sixth lens, and the seventh lens is too strong, and it is not easy to appropriately correct various aberrations, particularly, chromatic aberration. On the other hand, if f567 / f is 3.850 or more, it is not easy to reduce the diameter of each lens and the object-image distance, and it is not easy to achieve miniaturization of the entire wide-angle lens.

[0247] On the contrary, in the present embodiment, since the condition 5 is satisfied, there are advantages that various aberrations, particularly, chromatic aberration are easily and appropriately corrected and miniaturization is more easily achieved.

[0248] As described above, in the present embodiment, by constituting the wide-angle lens 1000 in the above-described manner, as shown in FIG. 17, it is easy to avoid the length of the entire lens system from becoming too long while ensuring optical performance. ​

[0249] (Embodiment 5)

[0250] ​ is a view showing a wide-angle lens of Embodiment 5 of the present application, ​ is a view showing field curvature and distortion of the wide-angle lens of Embodiment 5 of the present application, ​ is a view showing field curvature and distortion of the wide-angle lens of Embodiment 5 of the present application, ​ is a view showing the sagittal chromatic aberration (lateral chromatic aberration) of the wide-angle lens of Embodiment 5 of the present application, ​ is a view showing the spherical aberration (longitudinal aberration) of the wide-angle lens of Embodiment 5 of the present application, ​ is a view showing the lateral aberration of the wide-angle lens of Embodiment 5 of the present application. Here, in ​ , ​ , ​ , ​ , ​ ​In the graph, the correlation curve for red light R (wavelength: 656 nm) is labeled R, the correlation curve for green light G (wavelength: 588 nm) is labeled G, the correlation curve for blue light B (wavelength: 486 nm) is labeled B, T indicates the correlation with the meridional plane, and S indicates the correlation with the sagittal plane, and, in the graph, ​ In the graph, the maximum scale of the vertical axis is ± 50.000 μm.

[0251] As shown in FIG. 10A, the wide-angle lens 1000 according to the present embodiment includes, in order from the object side (L1 side), a first lens 110, a second lens 120, a third lens 130, a fourth lens 140, an aperture 180, a fifth lens 150, a sixth lens 160, and a seventh lens 170, wherein the sixth lens 160 and the seventh lens 170 are bonded together by an adhesive to constitute a bonded lens. ​

[0252] In this embodiment, the basic structure of the wide-angle lens 1000 (i.e., whether the first lens 110, the second lens 120, the third lens 130, the fourth lens 140, the fifth lens 150, the sixth lens 160, and the seventh lens 170 have positive or negative refractive power, whether they are glass lenses or plastic lenses, whether the object-side surface and the image-side surface are convex or concave, and whether they are spherical or aspherical) is the same as that of the wide-angle lens in Embodiment 1, and thus will not be described in detail here.

[0253] In addition, as shown in FIG. 10A, like in Embodiment 1, a light-shielding plate 190 is provided between the second lens 120 and the fourth lens 130, a filter 200 is disposed on the image side of the seventh lens 170, and an image pickup element 300 is disposed on the image side of the filter 200. ​ In the present embodiment, the effective focal length f of the entire lens system is 1.021 mm, the total track d is 13.398 mm, the image space F / # is 2, the maximum field of angle is 108 degrees, and the entrance pupil diameter HEP is 0.511 mm.

[0254] The physical properties of each surface of the wide-angle lens 1000 according to the present embodiment are shown in Table 9, and the aspherical coefficients of each surface of the wide-angle lens 1000 according to the present embodiment are shown in Table 10-1 and Table 10-2.

[0255] ( Table 9 )

[0256]

[0257]

[0258] ​​In Table 9 above, the units of the curvature radius, the thickness, and the focal distance are mm, Nd is the refractive index for a light ray of 587.56 nm, νd is the Abbe number, and * indicates an aspheric surface.

[0259] (Table 10-1)

[0260]

[0261] (Table 10-2)

[0262] ​ A8 A10 A12 A14 A16 3 -1.12779E-03 1.69605E-04 -9.24708E-06 0.00000E+00 0.00000E+00 4 5.54759E-02 -1.43828E-02 -3.40212E-05 0.00000E+00 0.00000E+00 5 4.27755E-03 -5.97392E-03 0.00000E+00 0.00000E+00 0.00000E+00 6 1.27283E-03 -1.01399E-02 2.46941E-03 0.00000E+00 0.00000E+00 7 -2.19533E-02 8.91100E-03 0.00000E+00 0.00000E+00 0.00000E+00 8 -2.59952E-02 1.31396E-02 0.00000E+00 0.00000E+00 0.00000E+00 12 -5.53989E-03 2.10400E-02 -2.03506E-02 6.17103E-03 0.00000E+00 13 7.91865E-02 -3.44941E-02 3.84031E-03 7.90842E-04 0.00000E+00 14 4.18221E-02 -1.79457E-02 3.88481E-03 -3.05248E-04 0.00000E+00

[0263] In Table 10-1 and Table 10-2 above, the curvature radius is set to a positive value in the case where the lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, and is set to a negative value in the case where the lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side.

[0264] Further, in Table 10-1 and Table 10-2 above, the aspheric coefficients A4, A6, A8, A10, A12, A14, and A16 at the time of expressing the aspheric shape of each surface by Mathematical Formula 1 above are shown.

[0265] Here, in the wide-angle lens 1000, the object-image distance d is 13.398 mm, and the entrance pupil diameter HEP is 0.511 mm, and thus, the following Condition 1 is satisfied:

[0266] d / HEP < 29.000

[0267] In Condition 1, if d / HEP is 29.000 or more, it is not easy to avoid the length of the entire lens system from becoming excessively long while securing optical performance.

[0268] On the contrary, in the present embodiment, since Condition 1 is satisfied, it is easy to avoid the length of the entire lens system from becoming excessively long while securing optical performance.

[0269] In particular, in the present embodiment, since the relationship of d / HEP < 27.000 is satisfied, it is even easier to avoid the length of the entire lens system from becoming excessively long while securing optical performance.

[0270] Further, in the wide-angle lens 1000, the object-image distance d is 13.398 mm, and the focal distance f of the entire lens system is 1.021 mm, and thus, the following Condition 2 is satisfied:

[0271] 11.000 < d / f < 15.000

[0272] In condition 2, if d / f is 11.000 or less, it is difficult to appropriately correct various aberrations, on the other hand, if d / f is 15.000 or more, the length of the entire lens system becomes too long.

[0273] On the contrary, in the present embodiment, since condition 2 is satisfied, it is easy to appropriately correct various aberrations, it is easy to obtain excellent optical characteristics, and it is possible to suppress the lens system from becoming too large while avoiding the length of the entire lens system from becoming too long.

[0274] Further, in the wide-angle lens 1000, the focal length f of the entire lens system is 1.021 mm, and the entrance pupil diameter HEP is 0.511 mm, and therefore, the following condition 3 is satisfied:

[0275] f / HEP < 2.3

[0276] In condition 3, if f / HEP is 2.3 or more, it is difficult to secure brightness.

[0277] On the contrary, in the present embodiment, since condition 3 is satisfied, it is possible to secure brightness, and therefore, it is possible to apply to a high-density imaging element.

[0278] Further, in the wide-angle lens 1000, the combined focal length f1234 of the first lens 110, the second lens 120, the third lens 130, and the fourth lens 140 is 4.142 mm, and the combined focal length f567 of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.679 mm, and therefore, the following condition 4 is satisfied:

[0279] 0.800 < f1234 / f567 < 8.000

[0280] In condition 4, if f1234 / f567 is 0.800 or less, the power of the front lens group composed of the first lens, the second lens, the third lens, and the fourth lens is too strong, it is difficult to appropriately correct various aberrations, on the other hand, if f1234 / f567 is 8.000 or more, the power of the front lens group composed of the first lens, the second lens, the third lens, and the fourth lens is too weak, it is difficult to reduce the diameter of each lens of the front lens group, and it is difficult to achieve miniaturization of the entire wide-angle lens.

[0281] On the contrary, in the present embodiment, since condition 4 is satisfied, it has the advantages that it is easy to appropriately correct various aberrations and it is easy to achieve miniaturization.

[0282] Further, in the wide-angle lens 1000, the composite focal distance f567 of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.679 mm, and the focal distance f of the entire lens system is 1.021 mm, and thus the following condition 5 is satisfied:

[0283] 2.800 < f567 / f < 3.850.

[0284] In the condition 5, if f567 / f is 2.800 or less, the power of the rear lens group composed of the fifth lens, the sixth lens, and the seventh lens is too strong, and it is not easy to appropriately correct various aberrations, particularly chromatic aberration, and on the other hand, if f567 / f is 3.850 or more, it is not easy to reduce the diameter of each lens and the object-image distance, and it is not easy to achieve the miniaturization of the entire wide-angle lens.

[0285] On the contrary, in the present embodiment, since the condition 5 is satisfied, it has the advantages that it is easy to appropriately correct various aberrations, particularly chromatic aberration, and it is easier to achieve miniaturization.

[0286] As described above, in the present embodiment, by constituting the wide-angle lens 1000 in the above-described manner, as shown in FIG. 17, it is easy to avoid the length of the entire lens system from becoming too long while ensuring optical performance. ​

[0287] (Embodiment 6)

[0288] ​ is a diagram showing the wide-angle lens of Embodiment 6 of the present application, ​ is a diagram showing the field curvature and distortion of the wide-angle lens of Embodiment 6 of the present application, ​ is a diagram showing the field curvature and distortion of the wide-angle lens of Embodiment 6 of the present application, ​ is a diagram showing the transverse chromatic aberration (lateral chromatic aberration) of the wide-angle lens of Embodiment 6 of the present application, ​ is a diagram showing the spherical aberration (longitudinal aberration) of the wide-angle lens of Embodiment 6 of the present application, ​ is a diagram showing the lateral aberration of the wide-angle lens of Embodiment 6 of the present application. Here, in ​ , ​ , ​ , ​ , ​ , the relevant curve for red light R (wavelength 656 nm) is labeled R, the relevant curve for green light G (wavelength 588 nm) is labeled G, the relevant curve for blue light B (wavelength 486 nm) is labeled B, T indicates the tangential direction, and S indicates the sagittal direction, and in ​ , the maximum scale of the vertical axis is ±50.000 μm.​

[0289] As ​ illustrated, the wide-angle lens 1000 includes, in order from the object side (L1 side), a first lens 110, a second lens 120, a third lens 130, a fourth lens 140, an aperture 180, a fifth lens 150, a sixth lens 160, and a seventh lens 170, wherein the sixth lens 160 and the seventh lens 170 are bonded together by an adhesive to constitute a bonded lens.

[0290] Here, since the basic structure of the wide-angle lens 1000 in the present embodiment (i.e., whether the first lens 110, the second lens 120, the third lens 130, the fourth lens 140, the fifth lens 150, the sixth lens 160, and the seventh lens 170 have positive or negative refractive power, are glass lenses or plastic lenses, whether the object-side surface and the image-side surface are convex or concave, and whether they are spherical or aspherical) is the same as that of the wide-angle lens in Embodiment 1, detailed explanation is not given here.

[0291] Further, as ​ illustrated, as in Embodiment 1, a light-shielding sheet 190 is provided between the second lens 120 and the fourth lens 130, a filter 200 is disposed on the image side of the seventh lens 170, and an image pickup element 300 is disposed on the image side of the filter 200.

[0292] In the present embodiment, the effective focal length f of the entire lens system is 1.018 mm, the total track d is 13.383 mm, the image space F / # is 2, the maximum field of angle is 108 degrees, and the entrance pupil diameter HEP is 0.509 mm.

[0293] The physical properties of each surface of the wide-angle lens 1000 of the present embodiment are shown in Table 11, and the aspherical coefficients of each surface of the wide-angle lens 1000 of the present embodiment are shown in Table 12-1 and Table 12-2.

[0294] (Table 11)

[0295]

[0296] In the above Table 11, the units of the radius of curvature, the thickness, and the effective focal length are mm, Nd is the refractive index for a light ray of 587.56 nm, νd is the Abbe number, and * indicates that it is an aspherical surface.

[0297] (Table 12-1)

[0298]

[0299] (Table 12-2)

[0300] ​ A8 A10 A12 A14 A16 3 -1.14938E-03 1.63223E-04 -7.82147E-06 0.00000E+00 0.00000E+00 4 5.61909E-02 -1.28652E-02 -3.10366E-04 0.00000E+00 0.00000E+00 5 2.71037E-03 -6.63668E-03 0.00000E+00 0.00000E+00 0.00000E+00 6 -3.16016E-03 -9.85165E-03 2.97746E-03 0.00000E+00 0.00000E+00 7 -1.96461E-02 8.38631E-03 0.00000E+00 0.00000E+00 0.00000E+00 8 -1.03312E-02 1.03923E-02 0.00000E+00 0.00000E+00 0.00000E+00 12 -8.59213E-03 1.81642E-02 -1.67818E-02 5.17215E-03 0.00000E+00 13 5.15225E-02 -2.02257E-02 1.88707E-03 3.30690E-04 0.00000E+00 14 4.12895E-02 -1.76625E-02 3.69776E-03 -2.59955E-04 0.00000E+00

[0301] In Tables 12-1 and 12-2 above, the curvature radius is set to a positive value in the case where the lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, and is set to a negative value in the case where the lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side.

[0302] Further, in Tables 12-1 and 12-2 above, aspherical coefficients A4, A6, A8, A10, A12, A14, A16 at the time of expressing the aspherical shape of each surface by Mathematical Formula 1 above are shown.

[0303] Here, in the wide-angle lens 1000, the object-image distance d is 13.383 mm, and the entrance pupil diameter HEP is 0.509 mm, and thus, the following Condition 1 is satisfied:

[0304] d / HEP < 29.000

[0305] In Condition 1, if d / HEP is 29.000 or more, it is not easy to avoid the length of the entire lens system from becoming excessively long while securing optical performance.

[0306] On the contrary, in the present embodiment, since Condition 1 is satisfied, it is easy to avoid the length of the entire lens system from becoming excessively long while securing optical performance.

[0307] In particular, in the present embodiment, since the relationship of d / HEP < 27.000 is satisfied, it is even easier to avoid the length of the entire lens system from becoming excessively long while securing optical performance.

[0308] Further, in the wide-angle lens 1000, the object-image distance d is 13.383 mm, and the focal distance f of the entire lens system is 1.018 mm, and thus, the following Condition 2 is satisfied:

[0309] 11.000 < d / f < 15.000

[0310] In Condition 2, if d / f is 11.000 or less, it is not easy to appropriately correct various aberrations, and on the other hand, if d / f is 15.000 or more, the length of the entire lens system becomes excessively long.

[0311] On the contrary, in the present embodiment, since Condition 2 is satisfied, it is easy to appropriately correct various aberrations, it is easy to obtain excellent optical characteristics, and it is possible to suppress the entire lens system from becoming excessively large while avoiding the length of the entire lens system from becoming excessively long.

[0312] Further, in the wide-angle lens 1000, the focal distance f of the entire lens system is 1.018 mm, and the entrance pupil diameter HEP is 0.509 mm, and thus the following condition 3 is satisfied:

[0313] f / HEP < 2.3

[0314] In the condition 3, if f / HEP is 2.3 or more, it is not easy to secure the luminance.

[0315] On the contrary, in the present embodiment, since the condition 3 is satisfied, the luminance can be secured, and thus the wide-angle lens can be applied to a high-density imaging device.

[0316] Further, in the wide-angle lens 1000, the combined focal distance f1234 of the first lens 110, the second lens 120, the third lens 130, and the fourth lens 140 is 4.528 mm, and the combined focal distance f567 of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.546 mm, and thus the following condition 4 is satisfied:

[0317] 0.800 < f1234 / f567 < 8.000

[0318] In the condition 4, if f1234 / f567 is 0.800 or less, the power of the front lens group composed of the first lens, the second lens, the third lens, and the fourth lens is too strong, and it is not easy to appropriately correct various aberrations, and on the other hand, if f1234 / f567 is 8.000 or more, the power of the front lens group composed of the first lens, the second lens, the third lens, and the fourth lens is too weak, and it is not easy to reduce the diameter of each lens of the front lens group, and it is not easy to achieve the miniaturization of the entire wide-angle lens.

[0319] On the contrary, in the present embodiment, since the condition 4 is satisfied, it has the advantages that it is easy to appropriately correct various aberrations and easy to achieve miniaturization.

[0320] Further, in the wide-angle lens 1000, the combined focal distance f567 of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.546 mm, and the focal distance f of the entire lens system is 1.018 mm, and thus the following condition 5 is satisfied:

[0321] 2.800 < f567 / f < 3.850.

[0322] In condition 5, if f567 / f is below 2.800, the optical focal length of the rear lens group consisting of the fifth, sixth, and seventh lenses will be too strong, making it difficult to properly correct various aberrations, especially chromatic aberration. On the other hand, if f567 / f is above 3.850, it will be difficult to reduce the diameter of each lens and the distance between the object and the image, making it difficult to achieve overall miniaturization of the wide-angle lens.

[0323] In contrast, in this embodiment, since condition 5 is satisfied, it has the advantages of being able to easily correct various aberrations, especially chromatic aberrations, and being easier to miniaturize.

[0324] In summary, in this embodiment, by constructing the wide-angle lens 1000 in the manner described above, as follows... ​ As shown, it is easy to ensure optical performance while avoiding the overall length of the lens system becoming too long.

[0325] (Implementation Method 7)

[0326] ​ This is an explanatory diagram showing the wide-angle lens according to Embodiment 7 of the present invention. ​ This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 7 of the present invention. ​ This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 7 of the present invention. ​ This is an explanatory diagram showing the transverse chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to Embodiment 7 of the present invention. ​ This is an explanatory diagram showing the spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 7 of the present invention. ​ This is an explanatory diagram illustrating the lateral aberration of the wide-angle lens according to Embodiment 7 of the present invention. Here, in ​ , ​ , ​ , ​ , ​ In the diagram, the correlation curve for red light R (wavelength 656nm) is labeled R, the correlation curve for green light G (wavelength 588nm) is labeled G, and the correlation curve for blue light B (wavelength 486nm) is labeled B. T represents correlation with the meridional plane, and S represents correlation with the sagittal plane. Furthermore, in... ​ In the figure, the maximum scale of the vertical axis is ±50.000 μm.

[0327] like ​ As shown, the wide-angle lens 1000 includes a first lens 110, a second lens 120, a third lens 130, a fourth lens 140, an aperture 180, a fifth lens 150, a sixth lens 160, and a seventh lens 170 arranged sequentially from the object side (L1 side). The sixth lens 160 and the seventh lens 170 are bonded together with an adhesive to form a joint lens.

[0328] In this embodiment, since the basic structure of the wide-angle lens 1000 (i.e., whether the first lens 110, the second lens 120, the third lens 130, the fourth lens 140, the fifth lens 150, the sixth lens 160, and the seventh lens 170 have positive or negative refractive power, are glass or plastic lenses, the object-side surface and the image-side surface are convex or concave, and are spherical or aspherical) is the same as that of the wide-angle lens in Embodiment 1, detailed description thereof will not be repeated here.

[0329] Further, as shown in FIG. 1, like Embodiment 1, a light-shielding sheet 190 is provided between the second lens 120 and the fourth lens 130, a filter 200 is disposed on the image side of the seventh lens 170, and an image pickup element 300 is disposed on the image side of the filter 200. ​

[0330] In this embodiment, the effective focal length f of the entire lens system is 1.019 mm, the total track d is 13.381 mm, the image space F / # is 2.0163, the maximum field of angle is 108 degrees, and the entrance pupil diameter HEP is 0.505 mm.

[0331] The physical properties of each surface of the wide-angle lens 1000 of this embodiment are shown in Table 13, and the aspherical coefficients of each surface of the wide-angle lens 1000 of this embodiment are shown in Table 14-1 and Table 14-2.

[0332] (Table 13)

[0333]

[0334] In Table 11 above, the units of the radius of curvature, the thickness, and the effective focal length are mm, Nd is the refractive index for a light ray of 587.56 nm, νd is the Abbe number, and * indicates that it is an aspherical surface.

[0335] (Table 14-1)

[0336]

[0337] (Table 14-2)

[0338] ​ A8 A10 A12 A14 A16 3 -1.15296E-03 1.63212E-04 -7.75247E-06 0.00000E+00 0.00000E+00 4 5.61909E-02 -1.28652E-02 -3.10366E-04 0.00000E+00 0.00000E+00 5 3.12004E-03 -6.74245E-03 0.00000E+00 0.00000E+00 0.00000E+00 6 -3.16016E-03 -9.85165E-03 2.97746E-03 0.00000E+00 0.00000E+00 7 -1.96461E-02 8.38631E-03 0.00000E+00 0.00000E+00 0.00000E+00 8 -1.03312E-02 1.03923E-02 0.00000E+00 0.00000E+00 0.00000E+00 12 -8.59213E-03 1.81642E-02 -1.67818E-02 5.17215E-03 0.00000E+00 13 5.15225E-02 -2.02257E-02 1.88707E-03 3.30690E-04 0.00000E+00 14 4.13120E-02 -1.76585E-02 3.69817E-03 -2.61279E-04 0.00000E+00

[0339] ​In Tables 14-1 and 14-2 above, the curvature radius is set to a positive value in the case where the lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, and is set to a negative value in the case where the lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side.

[0340] Further, in Tables 14-1 and 14-2 above, the aspheric coefficients A4, A6, A8, A10, A12, A14, and A16 at the time of expressing the aspheric shape of each surface by the above Mathematical Formula 1 are shown.

[0341] Here, in the wide-angle lens 1000, the object-image distance d is 13.381 mm, and the entrance pupil diameter HEP is 0.505 mm, and thus the following Condition 1 is satisfied:

[0342] d / HEP < 29.000

[0343] In Condition 1, if d / HEP is 29.000 or more, it is not easy to avoid the length of the entire lens system from becoming excessively long while securing optical performance.

[0344] On the contrary, in the present embodiment, since Condition 1 is satisfied, it is easy to avoid the length of the entire lens system from becoming excessively long while securing optical performance.

[0345] In particular, in the present embodiment, since the relationship of d / HEP < 27.000 is satisfied, it is even easier to avoid the length of the entire lens system from becoming excessively long while securing optical performance.

[0346] Further, in the wide-angle lens 1000, the object-image distance d is 13.381 mm, and the focal distance f of the entire lens system is 1.019 mm, and thus the following Condition 2 is satisfied:

[0347] 11.000 < d / f < 15.000

[0348] In Condition 2, if d / f is 11.000 or less, it is not easy to appropriately correct various aberrations, and on the other hand, if d / f is 15.000 or more, the length of the entire lens system becomes excessively long.

[0349] On the contrary, in the present embodiment, since Condition 2 is satisfied, it is easy to appropriately correct various aberrations, it is easy to obtain excellent optical characteristics, and it is possible to suppress the entire lens system from becoming excessively large while avoiding the length of the entire lens system from becoming excessively long.

[0350] Further, in the wide-angle lens 1000, the focal distance f of the entire lens system is 1.019 mm, and the entrance pupil diameter HEP is 0.505 mm, and thus the following Condition 3 is satisfied:

[0351] f / HEP < 2.3

[0352] In the condition 3, if f / HEP is 2.3 or more, it is difficult to secure the brightness.

[0353] On the contrary, in the present embodiment, since the condition 3 is satisfied, the brightness can be secured, and thus the imaging device can be applied to high densification.

[0354] Further, in the wide-angle lens 1000, the combined focal distance f1234 of the first lens 110, the second lens 120, the third lens 130, and the fourth lens 140 is 4.815 mm, and the combined focal distance f567 of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.557 mm, and thus the following condition 4 is satisfied:

[0355] 0.800 < f1234 / f567 < 8.000

[0356] In the condition 4, if f1234 / f567 is 0.800 or less, the power of the front lens group composed of the first lens, the second lens, the third lens, and the fourth lens is too strong, and it is difficult to appropriately correct various aberrations, and on the other hand, if f1234 / f567 is 8.000 or more, the power of the front lens group composed of the first lens, the second lens, the third lens, and the fourth lens is too weak, and it is difficult to reduce the diameter of each lens of the front lens group, and it is difficult to achieve the miniaturization of the entire wide-angle lens.

[0357] On the contrary, in the present embodiment, since the condition 4 is satisfied, it has the advantages that it is easy to appropriately correct various aberrations and easy to achieve miniaturization.

[0358] Further, in the wide-angle lens 1000, the combined focal distance f567 of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.557 mm, and the focal distance f of the entire lens system is 1.019 mm, and thus the following condition 5 is satisfied:

[0359] 2.800 < f567 / f < 3.850.

[0360] In the condition 5, if f567 / f is 2.800 or less, the power of the rear lens group composed of the fifth lens, the sixth lens, and the seventh lens is too strong, and it is difficult to appropriately correct various aberrations, particularly chromatic aberration, and on the other hand, if f567 / f is 3.850 or more, it is difficult to reduce the diameter of each lens and the object-image distance, and it is difficult to achieve the miniaturization of the entire wide-angle lens.

[0361] On the contrary, in the present embodiment, since the condition 5 is satisfied, it has the advantages that it is easy to appropriately correct various aberrations, particularly chromatic aberration, and it is easier to achieve miniaturization.

[0362] As described above, in the present embodiment, the wide-angle lens 1000 is configured in the above-described manner, so that it is easy to avoid the length of the entire lens system from becoming excessively long while ensuring optical performance. ​ As shown, it is easy to avoid the length of the entire lens system from becoming excessively long while ensuring optical performance.

[0363] (Embodiment 8)

[0364] ​ is a diagram illustrating the field curvature and distortion of the wide-angle lens of the present embodiment 8, ​ is a diagram illustrating the field curvature and distortion of the wide-angle lens of the present embodiment 8, ​ is a diagram illustrating the field curvature and distortion of the wide-angle lens of the present embodiment 8, ​ is a diagram illustrating the lateral chromatic aberration (transverse chromatic aberration) of the wide-angle lens of the present embodiment 8, ​ is a diagram illustrating the spherical aberration (longitudinal aberration) of the wide-angle lens of the present embodiment 8, ​ is a diagram illustrating the lateral aberration of the wide-angle lens of the present embodiment 8. Here, in ​ , ​ , ​ , ​ , ​ , the relevant curve for red light R (wavelength: 656 nm) is labeled R, the relevant curve for green light G (wavelength: 588 nm) is labeled G, the relevant curve for blue light B (wavelength: 486 nm) is labeled B, T indicates the tangential direction, and S indicates the sagittal direction, and in ​ , the maximum scale of the vertical axis is ±50.000 μm.

[0365] As shown in ​ , the wide-angle lens 1000 includes, in order from the object side (L1 side), a first lens 110, a second lens 120, a third lens 130, a fourth lens 140, an aperture 180, a fifth lens 150, a sixth lens 160, and a seventh lens 170, wherein the sixth lens 160 and the seventh lens 170 are bonded together by an adhesive to constitute a cemented lens.

[0366] Here, since the basic structure of the wide-angle lens 1000 in the present embodiment (i.e., whether the first lens 110, the second lens 120, the third lens 130, the fourth lens 140, the fifth lens 150, the sixth lens 160, and the seventh lens 170 have positive or negative refractive power, are glass lenses or plastic lenses, whether the object-side surface and the image-side surface are convex or concave, and whether they are spherical or aspherical) is the same as that of the wide-angle lens in Embodiment 1, it will not be described in detail here.

[0367] Further, as ​ As shown in FIG. 1, the wide-angle lens 1000 according to the present embodiment includes a first lens 110, a second lens 120, a third lens 130, a fourth lens 140, a fifth lens 150, a sixth lens 160, a seventh lens 170, an eighth lens 180, a ninth lens 190, and a tenth lens 200. The first lens 110 is a positive lens having a convex surface on the object side and a concave surface on the image side. The second lens 120 is a negative lens having a concave surface on the object side and a convex surface on the image side. The third lens 130 is a positive lens having a convex surface on the object side and a concave surface on the image side. The fourth lens 140 is a positive lens having a convex surface on the object side and a concave surface on the image side. The fifth lens 150 is a negative lens having a concave surface on the object side and a convex surface on the image side. The sixth lens 160 is a positive lens having a convex surface on the object side and a concave surface on the image side. The seventh lens 170 is a positive lens having a convex surface on the object side and a concave surface on the image side. The eighth lens 180 is a positive lens having a convex surface on the object side and a concave surface on the image side. The ninth lens 190 is a positive lens having a convex surface on the object side and a concave surface on the image side. The tenth lens 200 is a positive lens having a convex surface on the object side and a concave surface on the image side.

[0368] In the present embodiment, the focal distance f (Effective Focal Length) of the entire lens system is 1.030 mm, the object-image distance d (Total Track) is 13.609 mm, the F value (Image Space F / #) is 2, the maximum half field angle (Max. Field of Angle) is 106 degrees, and the entrance pupil diameter HEP is 0.515 mm.

[0369] The physical properties of each surface of the wide-angle lens 1000 according to the present embodiment are shown in Table 15, and the aspheric coefficients of each surface of the wide-angle lens 1000 according to the present embodiment are shown in Table 16-1 and Table 16-2.

[0370] ( Table 15 )

[0371]

[0372] In Table 15 above, the units of the radius of curvature, the thickness, and the focal distance are mm, Nd is the refractive index for a light ray of 587.56 nm, νd is the Abbe number, and * indicates an aspheric surface.

[0373] ( Table 16-1 )

[0374] ​ ​ K A4 A6 3 -4.38390E-02 0.00000E+00 1.02948E-02 -1.01140E-03 4 7.88668E-01 -1.13571E+00 5.66499E-02 1.84231E-03 5 2.82343E-01 0.00000E+00 -2.18543E-02 5.16357E-03 6 1.17050E-01 0.00000E+00 -6.48711E-02 -8.41810E-03 7 2.24418E-01 0.00000E+00 3.04785E-02 1.99197E-02 8 -1.03429E-01 0.00000E+00 9.05286E-02 3.48783E-02 12 -1.83670E-01 0.00000E+00 -3.32106E-02 4.95833E-02 13 9.17180E-01 -3.67711E+00 1.58393E-01 -3.03404E-02 14 -5.07238E-01 -6.42125E-01 3.25791E-02 -8.99922E-03

[0375] ( Table 16-2 )

[0376] ​ A8 A10 A12 A14 A16 3 2.82136E-05 8.57444E-16 0.00000E+00 0.00000E+00 0.00000E+00 4 3.99185E-02 -2.56858E-02 9.68214E-03 0.00000E+00 0.00000E+00 5 -3.88312E-04 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 6 3.26148E-03 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 7 -6.50576E-03 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 8 4.33217E-03 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 12 -4.63097E-02 2.53604E-02 -5.68334E-03 0.00000E+00 0.00000E+00 13 -2.77646E-02 2.45247E-02 -5.43979E-03 0.00000E+00 0.00000E+00 14 4.06471E-03 -7.04269E-04 4.21913E-05 0.00000E+00 0.00000E+00

[0377] In Table 16-1 and Table 16-2 above, the radius of curvature is set to a positive value in the case where the lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, and the radius of curvature is set to a negative value in the case where the lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side.

[0378] Further, in Table 16-1 and Table 16-2 above, the aspheric coefficients A4, A6, A8, A10, A12, A14, and A16 of each surface when the aspheric shape is expressed by Mathematical Formula 1 above are shown.

[0379] Here, in the wide-angle lens 1000, the object-image distance d is 13.609 mm, and the entrance pupil diameter HEP is 0.515 mm, and thus the following Condition 1 is satisfied:

[0380] d / HEP < 29.000

[0381] In the condition 1, if d / HEP is 29.000 or more, it is not easy to avoid the length of the entire lens system from becoming too long while securing the optical performance.

[0382] On the contrary, in the present embodiment, since the condition 1 is satisfied, it is easy to avoid the length of the entire lens system from becoming too long while securing the optical performance.

[0383] In particular, in the present embodiment, since the relation of d / HEP < 27.000 is satisfied, it is more easy to avoid the length of the entire lens system from becoming too long while securing the optical performance.

[0384] Further, in the wide-angle lens 1000, the object-image distance d is 13.609 mm, and the focal distance f of the entire lens system is 1.030 mm, and thus the following condition 2 is satisfied:

[0385] 11.000 < d / f < 15.000

[0386] In the condition 2, if d / f is 11.000 or less, it is not easy to properly correct various aberrations, and on the other hand, if d / f is 15.000 or more, the length of the entire lens system becomes too long.

[0387] On the contrary, in the present embodiment, since the condition 2 is satisfied, it is easy to properly correct various aberrations, it is easy to obtain excellent optical characteristics, and it is possible to suppress the entire lens system from becoming too large while avoiding the length of the entire lens system from becoming too long.

[0388] Further, in the wide-angle lens 1000, the focal distance f of the entire lens system is 1.030 mm, and the entrance pupil diameter HEP is 0.515 mm, and thus the following condition 3 is satisfied:

[0389] f / HEP < 2.3

[0390] In the condition 3, if f / HEP is 2.3 or more, it is not easy to secure the brightness.

[0391] On the contrary, in the present embodiment, since the condition 3 is satisfied, it is possible to secure the brightness, and thus it is possible to be applied to a high-density imaging element.

[0392] Further, in the wide-angle lens 1000, the combined focal distance f1234 of the first lens 110, the second lens 120, the third lens 130, and the fourth lens 140 is 21.864 mm, and the combined focal distance f567 of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.125 mm, and thus the following condition 4 is satisfied:

[0393] 0.800 < f1234 / f567 < 8.000

[0394] In Condition 4, if f1234 / f567 is 0.800 or less, the power of the front lens group composed of the first lens, the second lens, the third lens, and the fourth lens is too strong, and it is difficult to appropriately correct various aberrations. On the other hand, if f1234 / f567 is 8.000 or more, the power of the front lens group composed of the first lens, the second lens, the third lens, and the fourth lens is too weak, and it is difficult to reduce the diameters of the respective lenses of the front lens group and to achieve the miniaturization of the entire wide-angle lens.

[0395] On the contrary, in the present embodiment, since Condition 4 is satisfied, there are advantages that it is easy to appropriately correct various aberrations and to achieve the miniaturization.

[0396] Further, in the wide-angle lens 1000, the composite focal length f567 of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.125 mm, and the focal length f of the entire lens system is 1.030 mm, and thus Condition 5 below is satisfied:

[0397] 2.800 < f567 / f < 3.850.

[0398] In Condition 5, if f567 / f is 2.800 or less, the power of the rear lens group composed of the fifth lens, the sixth lens, and the seventh lens is too strong, and it is difficult to appropriately correct various aberrations, particularly chromatic aberration. On the other hand, if f567 / f is 3.850 or more, it is difficult to reduce the diameters of the respective lenses and the object-image distance, and to achieve the miniaturization of the entire wide-angle lens.

[0399] On the contrary, in the present embodiment, since Condition 5 is satisfied, there are advantages that it is easy to appropriately correct various aberrations, particularly chromatic aberration, and to achieve the miniaturization more easily.

[0400] As described above, in the present embodiment, by constituting the wide-angle lens 1000 in the above-described manner, as shown in FIG. 17, it is easy to avoid the length of the entire lens system from becoming too long while ensuring the optical performance. ​

[0401] (Embodiment 9)

[0402] ​ is a view that shows the wide-angle lens of Embodiment 9 of the present application, ​ is a view that shows the field curvature and the distortion of the wide-angle lens of Embodiment 9 of the present application, ​ is a view that shows the field curvature and the distortion of the wide-angle lens of Embodiment 9 of the present application, ​ ​is a graph showing the lateral chromatic aberration (transverse chromatic aberration) of the wide-angle lens of Embodiment 9 of the present application, ​ is a graph showing the longitudinal chromatic aberration (longitudinal chromatic aberration) of the wide-angle lens of Embodiment 9 of the present application, ​ is a graph showing the lateral chromatic aberration of the wide-angle lens of Embodiment 9 of the present application. Here, in ​ , ​ , ​ , ​ , ​ , the relevant curve for red light R (wavelength: 656 nm) is labeled R, the relevant curve for green light G (wavelength: 588 nm) is labeled G, the relevant curve for blue light B (wavelength: 486 nm) is labeled B, T indicates the tangential direction, S indicates the sagittal direction, and in ​ , the maximum scale of the vertical axis is ±50.000 μm.

[0403] As shown in ​ , the wide-angle lens 1000 includes, in order from the object side (L1 side), a first lens 110, a second lens 120, a third lens 130, a fourth lens 140, an aperture 180, a fifth lens 150, a sixth lens 160, and a seventh lens 170, wherein the sixth lens 160 and the seventh lens 170 are bonded together by an adhesive to form a bonded lens.

[0404] Here, since the basic structure of the wide-angle lens 1000 in this embodiment (i.e., whether the first lens 110, the second lens 120, the third lens 130, the fourth lens 140, the fifth lens 150, the sixth lens 160, and the seventh lens 170 have positive or negative refractive power, are glass or plastic lenses, whether the object side surface and the image side surface are convex or concave, and whether they are spherical or aspherical) is the same as that of the wide-angle lens in Embodiment 1, it will not be described in detail here.

[0405] Further, as shown in ​ , as in Embodiment 1, a light shield 190 is provided between the second lens 120 and the fourth lens 130, a filter 200 is disposed on the image side of the seventh lens 170, and an image pickup element 300 is disposed on the image side of the filter 200.

[0406] In the present embodiment, the effective focal length f of the entire lens system is 1.019 mm, the total track d is 13.397 mm, the image space F / # is 2.012, the maximum field of angle is 108.004 degrees, and the entrance pupil diameter HEP is 0.506 mm.

[0407] The physical properties of each surface of the wide-angle lens 1000 of the present embodiment are shown in Table 17, and the aspheric coefficients of each surface of the wide-angle lens 1000 of the present embodiment are shown in Table 18-1 and Table 18-2.

[0408] (Table 17)

[0409]

[0410] In Table 17 above, the units of the radius of curvature, the thickness, and the focal length are mm, Nd is the refractive index for a light ray of 587.56 nm, νd is the Abbe number, and * indicates an aspheric surface.

[0411] (Table 18-1)

[0412]

[0413] (Table 18-2)

[0414] ​ A8 A10 A12 A14 A16 3 -6.11588E-05 1.50045E-05 3.90615E-08 0.00000E+00 0.00000E+00 4 4.96308E-02 -1.37651E-02 1.87863E-04 0.00000E+00 0.00000E+00 5 2.50539E-03 -1.94316E-04 -2.18386E-04 0.00000E+00 0.00000E+00 6 2.37631E-03 4.68175E-04 1.19525E-03 0.00000E+00 0.00000E+00 7 1.14133E-02 6.53638E-04 0.00000E+00 0.00000E+00 0.00000E+00 8 1.36753E-02 -1.98505E-03 0.00000E+00 0.00000E+00 0.00000E+00 12 3.38366E-03 -2.00010E-03 6.86525E-04 0.00000E+00 0.00000E+00 13 2.79270E-02 -5.22149E-03 -1.20343E-04 0.00000E+00 0.00000E+00 14 2.26165E-02 -7.19858E-03 9.87041E-04 0.00000E+00 0.00000E+00

[0415] In Table 18-1 and Table 18-2 above, the radius of curvature is set to a positive value in the case where the lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, and is set to a negative value in the case where the lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side.

[0416] Further, in Table 18-1 and Table 18-2 above, the aspheric coefficients A4, A6, A8, A10, A12, A14, and A16 at the time of expressing the aspheric shape of each surface by the above mathematical expression 1 are shown.

[0417] Here, in the wide-angle lens 1000, the total track d is 13.397 mm, and the entrance pupil diameter HEP is 0.506 mm, and thus, the following condition 1 is satisfied:

[0418] d / HEP < 29.000

[0419] In condition 1, if d / HEP is 29.000 or more, it is not easy to avoid the length of the entire lens system from becoming too long while ensuring optical performance.

[0420] On the contrary, in the present embodiment, since the condition 1 is satisfied, it is easy to avoid the length of the entire lens system from becoming too long while securing the optical performance.

[0421] In particular, in the present embodiment, since the relation of d / HEP < 27.000 is satisfied, it is easier to avoid the length of the entire lens system from becoming too long while securing the optical performance.

[0422] Further, in the wide-angle lens 1000, the object-image distance d is 13.397 mm, and the focal distance f of the entire lens system is 1.019 mm, and thus the following condition 2 is satisfied:

[0423] 11.000 < d / f < 15.000

[0424] In the condition 2, if d / f is 11.000 or less, it is not easy to properly correct various aberrations, and on the other hand, if d / f is 15.000 or more, the length of the entire lens system becomes too long.

[0425] On the contrary, in the present embodiment, since the condition 2 is satisfied, it is easy to properly correct various aberrations, it is easy to obtain excellent optical characteristics, and it is possible to suppress the entire lens system from becoming too large while avoiding the length of the entire lens system from becoming too long.

[0426] Further, in the wide-angle lens 1000, the focal distance f of the entire lens system is 1.019 mm, and the incident pupil diameter HEP is 0.506 mm, and thus the following condition 3 is satisfied:

[0427] f / HEP < 2.3

[0428] In the condition 3, if f / HEP is 2.3 or more, it is not easy to secure the brightness.

[0429] On the contrary, in the present embodiment, since the condition 3 is satisfied, it is possible to secure the brightness, and thus it is possible to be applied to a high-density imaging element.

[0430] Further, in the wide-angle lens 1000, the combined focal distance f1234 of the first lens 110, the second lens 120, the third lens 130, and the fourth lens 140 is 26.363 mm, and the combined focal distance f567 of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.374 mm, and thus the following condition 4 is satisfied:

[0431] 0.800 < f1234 / f567 < 8.000

[0432] In the condition 4, if f1234 / f567 is 0.800 or less, the power of the front lens group composed of the first lens, the second lens, the third lens, and the fourth lens is too strong, and it is difficult to appropriately correct various aberrations. On the other hand, if f1234 / f567 is 8.000 or more, the power of the front lens group composed of the first lens, the second lens, the third lens, and the fourth lens is too weak, and it is difficult to reduce the diameter of each lens of the front lens group and to achieve the miniaturization of the wide-angle lens as a whole.

[0433] On the contrary, in the present embodiment, since the condition 4 is satisfied, it has the advantages that it is easy to appropriately correct various aberrations and to achieve the miniaturization.

[0434] Further, in the wide-angle lens 1000, the composite focal length f567 of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.374 mm, and the focal length f of the lens system as a whole is 1.019 mm, and thus the following condition 5 is satisfied:

[0435] 2.800 < f567 / f < 3.850.

[0436] In the condition 5, if f567 / f is 2.800 or less, the power of the rear lens group composed of the fifth lens, the sixth lens, and the seventh lens is too strong, and it is difficult to appropriately correct various aberrations, particularly chromatic aberration. On the other hand, if f567 / f is 3.850 or more, it is difficult to reduce the diameter of each lens and the object-image distance, and to achieve the miniaturization of the wide-angle lens as a whole.

[0437] On the contrary, in the present embodiment, since the condition 5 is satisfied, it has the advantages that it is easy to appropriately correct various aberrations, particularly chromatic aberration, and to achieve the miniaturization more easily.

[0438] As described above, in the present embodiment, by constituting the wide-angle lens 1000 in the above-described manner, as shown in FIG. 10, it is easy to avoid the length of the lens system as a whole from becoming too long while ensuring the optical performance. ​

[0439] The present application has been described above by way of example with reference to the accompanying drawings, and it is obvious that the concrete implementation of the present application is not limited to the above-described embodiments.

[0440] For example, in the above-described embodiments, the shape of the first surface 1 of the first lens 110, the shape of the third surface 3 of the second lens 120, the shape of the fifth surface 5 of the third lens 130, the shape of the seventh surface 7 of the fourth lens 140, and the shape of the twelfth surface 12 of the sixth lens 160 can be appropriately changed as needed.

[0441] ​Further, in the above-described embodiments, the first lens 110 and the fifth lens 150 can also be constituted by plastic lenses, and the second lens 120, the third lens 130, the fourth lens 140, the sixth lens 160, and the seventh lens 170 can also be constituted by glass lenses.

Claims

1. A wide-angle lens, characterized in that, It includes a first lens, a second lens, a third lens, a fourth lens, an aperture, a fifth lens, a sixth lens, and a seventh lens arranged sequentially from the object side, and the number of lenses with optical power is seven. The sixth lens and the seventh lens constitute a combined lens. The first lens is a negative lens with its concave surface facing the image side. The second lens is a negative lens with its concave surface facing the image side. The third lens is a positive lens with its convex surface facing the image side. The fourth lens is a positive lens with its convex surface facing the image side. The fifth lens is a positive lens with its convex surface facing the object side and its convex surface facing the image side. The sixth lens is a negative lens with its concave surface facing the image side. The seventh lens is a positive lens with its convex surface facing the object side and its convex surface facing the image side. When the object-image distance of the wide-angle lens is set to d and the entrance pupil diameter of the wide-angle lens is set to HEP, the following relationship is satisfied: d / HEP < 29.000 When the combined focal distance of the first lens, the second lens, the third lens, and the fourth lens is set to f1234, and the combined focal distance of the fifth lens, the sixth lens, and the seventh lens is set to f567, the following relationship is satisfied: 0.800 < f1234 / f567 < 8.000 When the focal distance of the entire wide-angle lens is set to f, the following relationship is satisfied: 11.000 < d / f < 15.

000.

2. The wide-angle lens as described in claim 1, characterized in that, The following relationship must be satisfied: d / HEP < 27.

000.

3. The wide-angle lens as described in claim 1 or 2, characterized in that, The following relationship must be satisfied: f / HEP < 2.

3.

4. The wide-angle lens as described in claim 1, characterized in that, The following relationship must be satisfied: 2.800 < f567 / f < 3.

850.

5. The wide-angle lens as described in claim 1, characterized in that, The first lens and the fifth lens are both glass lenses. The second lens, the third lens, the fourth lens, the sixth lens, and the seventh lens are all plastic lenses.

Images