wide-angle lens

Abstract

A wide-angle lens, wherein the wide-angle lens includes a lens group and an aperture, the multiple lenses in the lens group are arranged in sequence from the object side in a manner of sandwiching the aperture, when the maximum half field angle of the wide-angle lens as a whole is set to ω, the following relationship is satisfied: 98°<ω<120°, when the focal length of the wide-angle lens as a whole is set to f and the incident pupil diameter of the wide-angle lens as a whole is set to HEP, the following relationship is satisfied: f / HEP<2.3, the lens group includes a first lens, the first lens is arranged at the position closest to the object side, and the first lens is a negative lens with a concave surface facing the image side, when the effective radius of the image-side lens surface of the first lens is set to sd12 and the curvature radius of the image-side lens surface of the first lens is set to R12, the following relationship is satisfied: 0.890<sd12 / R12<0.970.

Description

Technical Field

[0001] The present invention relates to a wide-angle lens. Background Art

[0002] As a lens installed in a vehicle-mounted camera, etc., there has conventionally been a wide-angle lens comprising 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 in order from the object side, wherein the sixth lens and the seventh lens constitute a cemented lens (for example, see Patent Document 1).

[0003] Patent Document 1: Japanese Patent Application Publication No. 2018-60153

[0004] In practice, it is sometimes necessary to miniaturize a vehicle-mounted camera equipped with the wide-angle lens. In this case, the wide-angle lens must be miniaturized. However, miniaturization of the wide-angle lens tends to reduce the maximum half-field angle of the camera. Summary of the Invention

[0005] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a wide-angle lens that can achieve miniaturization while widening the maximum half-field angle.

[0006] In order to achieve the above-mentioned purpose, the present invention provides a wide-angle lens, wherein the wide-angle lens includes a lens group and an aperture, and the multiple lenses in the lens group are arranged in sequence from the object side in a manner of clamping the aperture, when the maximum half field angle of the wide-angle lens as a whole is set to ω, the following relationship is satisfied: 98°<ω<120°, when the focal length of the wide-angle lens as a whole is set to f and the incident pupil diameter of the wide-angle lens as a whole is set to HEP, the following relationship is satisfied: f / HEP<2.3, the lens group includes a first lens, the first lens is arranged at the position closest to the object side, and the first lens is a negative lens with a concave surface facing the image side, when the effective radius of the image-side lens surface of the first lens is set to sd12 and the curvature radius of the image-side lens surface of the first lens is set to R12, the following relationship is satisfied: 0.890<sd12 / R12<0.970.

[0007] According to the wide-angle lens of the present invention, when the maximum half-field angle of view of the entire wide-angle lens is set to ω, the following relationship is satisfied: 98° < ω < 120°. Thus, by setting the maximum half-field angle greater than 98°, the maximum half-field angle can be expanded. Furthermore, by setting the maximum half-field angle less than 120°, the peripheral portion of the image can be prevented from being darkened due to the light intensity ratio at the lens periphery being less than that at the center. This allows the wide-angle lens to be miniaturized while simultaneously expanding its maximum half-field angle.

[0008] Furthermore, when the focal length of the entire wide-angle lens is f and the entrance pupil diameter of the entire wide-angle lens is HEP, the relationship f / HEP < 2.3 is satisfied. This ensures the brightness of the wide-angle lens and makes it suitable for high-pixel imaging devices.

[0009] Furthermore, when the effective radius of the image-side lens surface of the first lens is sd12 and the radius of curvature of the image-side lens surface of the first lens is R12, the relationship 0.890 < sd12 / R12 < 0.970 is satisfied. Thus, by setting the ratio of the effective radius sd12 of the image-side lens surface of the first lens to the radius of curvature R12 to be greater than 0.890, the maximum half-angle of view can be increased, particularly to 98° or greater. Furthermore, by setting the ratio of the effective radius sd12 of the image-side lens surface of the first lens to the radius of curvature R12 to be less than 0.970, the angle formed between the peripheral portion of the image-side lens surface of the first lens and the tangent line can be suppressed from being too small, thereby preventing the image-side lens surface of the first lens from being unable to be polished.

[0010] Furthermore, in the wide-angle lens of the present invention, when the radius of curvature of the object-side lens surface of the first lens is set to R11 and the radius of curvature of the image-side lens surface of the first lens is set to R12, the relationship of 1.300 < (R11 + R12) / (R11 - R12) < 1.900 is preferably satisfied, and the relationship of 1.600 < (R11 + R12) / (R11 - R12) < 1.850 is more preferably satisfied.

[0011] According to the wide-angle lens of the present invention, when the curvature radius of the object-side lens surface of the first lens is R11 and the curvature radius is R12, respectively, the relationship of 1.300 < (R11 + R12) / (R11 - R12) < 1.900 is satisfied, and further, the relationship of 1.600 < (R11 + R12) / (R11 - R12) < 1.850 is satisfied. Therefore, by setting (R11+R12) / (R11-R12) to be greater than 1.300, the curvature radius of the image-side lens surface of the first lens can be prevented from being too small, thereby facilitating the molding of the image-side lens surface of the first lens. On the other hand, the curvature radius of the object-side lens surface of the first lens can be prevented from being too large, thereby preventing the diameter of the first lens from being too large, thereby achieving miniaturization of the wide-angle lens. Furthermore, by setting (R11+R12) / (R11-R12) to be less than 1.900, it is possible to ensure that the first lens has sufficient optical power, thereby facilitating the expansion of the maximum half-field-of-view angle of the first lens, and to ensure that the first lens has sufficient thickness to prevent the first lens from being damaged by impact, etc.

[0012] In addition, by further setting (R11+R12) / (R11-R12) to be greater than 1.600, the curvature radius of the image-side lens surface of the first lens can be further suppressed from being too small, thereby making it easier to shape the image-side lens surface of the first lens. On the other hand, the curvature radius of the object-side lens surface of the first lens can be further suppressed from being too large, thereby further suppressing the diameter of the first lens from being too large, thereby further achieving miniaturization of the wide-angle lens. In addition, by further setting (R11+R12) / (R11-R12) to be less than 1.850, it can be further ensured that the first lens has sufficient optical power, thereby making it easier to expand the maximum half field of view of the first lens, and it can be further ensured that the first lens has sufficient thickness to further suppress damage to the first lens caused by impact, etc.

[0013] Furthermore, in the wide-angle lens of the present invention, preferably, when the thickness of the first lens is T1 and the sag height of the image-side lens surface of the first lens is Sag12, the following relationship is satisfied: 0.700<T1 / Sag12<1.100.

[0014] According to the wide-angle lens of the present invention, by setting the ratio of the thickness T1 of the first lens to the sag height Sag12 of the image-side lens surface of the first lens to be greater than 0.700, it is possible to ensure that the first lens has a sufficient thickness to prevent the first lens from being damaged by impact; in addition, by setting the ratio of the thickness T1 of the first lens to the sag height Sag12 of the image-side lens surface of the first lens to be less than 1.100, it is possible to prevent the thickness of the first lens from being too thick, thereby preventing the ideal negative optical focal length from being obtained.

[0015] (Effects of the Invention)

[0016] According to the present invention, when the maximum half-field angle of view of the wide-angle lens as a whole is set to ω, the following relationship is satisfied: 98° < ω < 120°. Thus, by setting the maximum half-field angle to greater than 98°, the maximum half-field angle can be expanded. Furthermore, by setting the maximum half-field angle to less than 120°, the peripheral portion of the image can be prevented from being darkened due to the light intensity ratio at the lens periphery being less than the light intensity ratio at the center, thereby achieving miniaturization while expanding the maximum half-field angle of the wide-angle lens. Furthermore, when the focal length of the wide-angle lens as a whole is set to f and the entrance pupil diameter of the wide-angle lens as a whole is set to HEP, the relationship f / HEP < 2.3 is satisfied. This ensures the brightness of the wide-angle lens and makes the wide-angle lens suitable for high-pixel imaging elements. Furthermore, when the effective radius of the image-side lens surface of the first lens is set to sd12 and the radius of curvature of the image-side lens surface of the first lens is set to R12, the relationship 0.890 < sd12 / R12 < 0.970 is satisfied. Thus, by setting the ratio of the effective radius sd12 of the image-side lens surface of the first lens to the radius of curvature R12 to be greater than 0.890, the maximum half-field angle can be increased, and in particular, the maximum half-field angle can be increased to 98° or more. In addition, by setting the ratio of the effective radius sd12 of the image-side lens surface of the first lens to the radius of curvature R12 to be less than 0.970, the angle formed between the peripheral portion of the image-side lens surface of the first lens and the tangent line can be suppressed from being too small, thereby preventing the image-side lens surface of the first lens from being unable to be polished. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is an explanatory diagram showing a wide-angle lens according to Embodiment 1 of the present invention.

[0018] Figure 2A These are explanatory diagrams showing field curvature and distortion of the wide-angle lens according to the first embodiment of the present invention.

[0019] Figure 2B These are explanatory diagrams showing field curvature and distortion of the wide-angle lens according to the first embodiment of the present invention.

[0020] Figure 3A This is an explanatory diagram showing vertical axial chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to the first embodiment of the present invention.

[0021] Figure 3B This is an explanatory diagram showing spherical aberration (longitudinal aberration) of the wide-angle lens according to the first embodiment of the present invention.

[0022] Figures 4A to 4L These are explanatory diagrams showing lateral aberrations of the wide-angle lens according to the first embodiment of the present invention.

[0023] Figure 5 This is an explanatory diagram showing a wide-angle lens according to Embodiment 2 of the present invention.

[0024] Figure 6A These are explanatory diagrams showing field curvature and distortion of a wide-angle lens according to Embodiment 2 of the present invention.

[0025] Figure 6B These are explanatory diagrams showing field curvature and distortion of a wide-angle lens according to Embodiment 2 of the present invention.

[0026] Figure 7A This is an explanatory diagram showing vertical axial chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to the second embodiment of the present invention.

[0027] Figure 7B This is an explanatory diagram showing spherical aberration (longitudinal aberration) of the wide-angle lens according to the second embodiment of the present invention.

[0028] Figures 8A to 8L It is an explanatory diagram showing lateral aberration of the wide-angle lens according to the second embodiment of the present invention.

[0029] Figure 9 This is an explanatory diagram showing a wide-angle lens according to Embodiment 3 of the present invention.

[0030] Figure 10A These are explanatory diagrams showing field curvature and distortion of a wide-angle lens according to Embodiment 3 of the present invention.

[0031] Figure 10B These are explanatory diagrams showing field curvature and distortion of a wide-angle lens according to Embodiment 3 of the present invention.

[0032] Figure 11A This is an explanatory diagram showing vertical axial chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to the third embodiment of the present invention.

[0033] Figure 11B This is an explanatory diagram showing spherical aberration (longitudinal aberration) of the wide-angle lens according to the third embodiment of the present invention.

[0034] Figures 12A to 12L It is an explanatory diagram showing lateral aberration of the wide-angle lens according to the third embodiment of the present invention.

[0035] Figure 13 This is an explanatory diagram showing a wide-angle lens according to a fourth embodiment of the present invention.

[0036] Figure 14A It is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to the fourth embodiment of the present invention.

[0037] Figure 14B It is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to the fourth embodiment of the present invention.

[0038] Figure 15A This is an explanatory diagram showing vertical axial chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to the fourth embodiment of the present invention.

[0039] Figure 15B This is an explanatory diagram showing spherical aberration (longitudinal aberration) of the wide-angle lens according to the fourth embodiment of the present invention.

[0040] Figures 16A to 16L It is an explanatory diagram showing lateral aberration of the wide-angle lens according to the fourth embodiment of the present invention.

[0041] Figure 17 This is an explanatory diagram showing a wide-angle lens according to Embodiment 5 of the present invention.

[0042] Figure 18A It is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to the fifth embodiment of the present invention.

[0043] Figure 18B It is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to the fifth embodiment of the present invention.

[0044] Figure 19A This is an explanatory diagram showing vertical axial chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to the fifth embodiment of the present invention.

[0045] Figure 19B This is an explanatory diagram showing spherical aberration (longitudinal aberration) of the wide-angle lens according to the fifth embodiment of the present invention.

[0046] Figures 20A to 20L It is an explanatory diagram showing lateral aberration of the wide-angle lens according to the fifth embodiment of the present invention.

[0047] Figure 21 This is an explanatory diagram showing a wide-angle lens according to Embodiment 6 of the present invention.

[0048] Figure 22A It is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to the sixth embodiment of the present invention.

[0049] Figure 22B It is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to the sixth embodiment of the present invention.

[0050] Figure 23A This is an explanatory diagram showing vertical axial chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to the sixth embodiment of the present invention.

[0051] Figure 23B This is an explanatory diagram showing spherical aberration (longitudinal aberration) of the wide-angle lens according to the sixth embodiment of the present invention.

[0052] Figures 24A to 24L It is an explanatory diagram showing lateral aberration of the wide-angle lens according to the sixth embodiment of the present invention.

[0053] Figure 25 This is an explanatory diagram showing a wide-angle lens according to Embodiment 7 of the present invention.

[0054] Figure 26A It is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to the seventh embodiment of the present invention.

[0055] Figure 26B It is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to the seventh embodiment of the present invention.

[0056] Figure 27A This is an explanatory diagram showing vertical axial chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to Embodiment 7 of the present invention.

[0057] Figure 27B This is an explanatory diagram showing spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 7 of the present invention.

[0058] Figures 28A to 28L It is an explanatory diagram showing lateral aberration of the wide-angle lens according to Embodiment 7 of the present invention.

[0059] Figure 29 This is an explanatory diagram showing a wide-angle lens according to an eighth embodiment of the present invention.

[0060] Figure 30A It is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to the eighth embodiment of the present invention.

[0061] Figure 30B It is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to the eighth embodiment of the present invention.

[0062] Figure 31A This is an explanatory diagram showing vertical axial chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to the eighth embodiment of the present invention.

[0063] Figure 31B This is an explanatory diagram showing spherical aberration (longitudinal aberration) of the wide-angle lens according to the eighth embodiment of the present invention.

[0064] Figures 32A to 32L It is an explanatory diagram showing lateral aberration of the wide-angle lens according to the eighth embodiment of the present invention.

[0065] Figure 33 This is an explanatory diagram showing a wide-angle lens according to Embodiment 9 of the present invention.

[0066] Figure 34A It is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to the ninth embodiment of the present invention.

[0067] Figure 34B It is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to the ninth embodiment of the present invention.

[0068] Figure 35A This is an explanatory diagram showing vertical axial chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to Embodiment 9 of the present invention.

[0069] Figure 35B This is an explanatory diagram showing spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 9 of the present invention.

[0070] Figures 36A to 36L It is an explanatory diagram showing lateral aberration of the wide-angle lens according to Embodiment 9 of the present invention.

[0071] (Explanation of Symbols)

[0072] 1000 wide-angle lens

[0073] 110 First lens

[0074] 120 Second lens

[0075] 130 Third lens

[0076] 140 Fourth lens

[0077] 150 Fifth lens

[0078] 160 Sixth lens

[0079] 170 Seventh Lens

[0080] 180 aperture

[0081] 190 shading sheet

[0082] 200 filters

[0083] 300 camera components DETAILED DESCRIPTION

[0084] Hereinafter, various embodiments of the wide-angle lens of the present invention will be described with reference to the accompanying drawings. In the following description, in the extending direction of the optical axis L, the object side is labeled L1 and the image side is labeled L2.

[0085] (Implementation 1)

[0086] Figure 1 1 is an explanatory diagram showing a wide-angle lens according to Embodiment 1 of the present invention. Figure 2A 1 is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to the first embodiment of the present invention. Figure 2B 1 is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to the first embodiment of the present invention. Figure 3A 1 is an explanatory diagram showing vertical axial chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to the first embodiment of the present invention. Figure 3B 1 is an explanatory diagram showing spherical aberration (longitudinal aberration) of the wide-angle lens according to the first embodiment of the present invention. Figures 4A to 4L This is an explanatory diagram showing the lateral aberration of the wide-angle lens according to the first embodiment of the present invention. Figure 2A 、 Figure 2B 、 Figure 3A、 Figure 3B 、 Figures 4A to 4L In the figure, the correlation curve of red light R (wavelength of 656nm) is marked with R, the correlation curve of green light G (wavelength of 588nm) is marked with G, and the correlation curve of blue light B (wavelength of 486nm) is marked with B. T is used to indicate correlation with the meridian plane, and S is used to indicate correlation with the sagittal plane. In addition, Figures 4A to 4L In the example, the maximum scale of the vertical axis is ±50.000 μm.

[0087] like Figure 1 As shown, the wide-angle lens 1000 includes, arranged in order from the object side (L1 side), a first lens 110 (i.e., the first lens 110 is arranged at the position closest to the object side), a second lens 120 (i.e., the second lens 120 is arranged adjacent to the image side of the first lens 110), 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 cemented lens.

[0088] Here, the first lens 110 is a lens (referred to as a negative lens) with a convex surface (first surface 1) facing the object side L1 and a concave surface (second surface 2) facing the image side L2, and has negative optical power. In this embodiment, the first lens 110 is a glass lens with a spherical first surface 1 and a spherical second surface 2.

[0089] The second lens 120 is a lens with negative optical power, with a convex surface (third surface 3) facing the object side L1 and a concave surface (fourth surface 4) facing the image side L2. In this embodiment, the second lens 120 is a plastic lens with aspherical third surface 3 and fourth surface 4.

[0090] The third lens 130 is a lens (referred to as a positive lens) with positive optical power, with its concave surface (fifth surface 5) facing the object side L1 and its convex surface (sixth surface 6) facing the image side L2. In this embodiment, the third lens 130 is a plastic lens with aspherical fifth and sixth surfaces 5 and 6.

[0091] The fourth lens 140 is a lens with positive refractive power, with its concave surface (the seventh surface 7) facing the object side L1 and its convex surface (the eighth surface 8) facing the image side L2. In this embodiment, the fourth lens 140 is a plastic lens with its seventh surface 7 and eighth surface 8 being aspherical.

[0092] The fifth lens 150 is a lens having positive refractive power, with its convex surface (the tenth surface 10 ) facing the object side L1 and its convex surface (the eleventh surface 11 ) facing the image side L2 . In this embodiment, the fifth lens 150 is formed of a glass lens.

[0093] The sixth lens 160 is a lens with negative refractive power, with its concave surface (the twelfth surface 12) facing the object side L1 and its concave surface (the thirteenth surface 13) facing the image side L2. It forms a cemented lens with the seventh lens 170. In this embodiment, the sixth lens 160 is a plastic lens with its twelfth surface 12 and thirteenth surface 13 being aspherical surfaces.

[0094] The seventh lens 170 is a lens with positive refractive power, with its convex surface (the 13th surface 13) facing the object side L1 and its convex surface (the 14th surface 14) facing the image side L2. In this embodiment, the seventh lens 170 is a plastic lens with its 13th surface 13 and 14th surface 14 being aspherical.

[0095] In addition, in this embodiment, if Figure 1 As shown, a light shielding sheet 190 is provided between the second lens 120 and the fourth lens 130 , a filter 200 is arranged on the image side of the seventh lens 170 , and an imaging element 300 is arranged on the image side of the filter 200 .

[0096] In this embodiment, the focal length f (Effective Focal Length) of the entire lens system is 1.023 mm, the object-image distance d (Total Track) is 13.611 mm, the F value (Image Space F / #) is 2.02, the maximum half field of view (Max. Field of Angle) is 115 degrees, and the entrance pupil diameter HEP is 0.507 mm.

[0097] Table 1 shows the physical properties of each surface of the wide-angle lens 1000 according to this embodiment, and Tables 2-1 and 2-2 show the aspheric coefficient of each surface of the wide-angle lens 1000 according to this embodiment.

[0098] (Table 1)

[0099]

[0100] In Table 1 above, the units of curvature radius, thickness, focal length, effective radius, and sagittal height are mm, Nd is the refractive index for light of 587.56 nm, νd is the Abbe number, and * indicates an aspheric surface.

[0101] (Table 2-1)

[0102] noodle c(1 / radius of curvature) K A4 A6 3 2.45778E-02 0.00000E+00 -7.34647E-04 0.00000E+00 4 8.18649E-01 -1.00000E+00 3.34909E-02 1.52429E-02 5 -8.48284E-02 0.00000E+00 -1.05901E-02 2.28744E-02 6 -3.50286E-01 0.00000E+00 4.60516E-02 1.35719E-02 7 -7.51052E-02 0.00000E+00 6.96916E-02 5.26973E-04 8 -3.86206E-01 0.00000E+00 4.85130E-02 1.07658E-02 12 -1.94439E-01 0.00000E+00 1.37213E-02 -3.80723E-02 13 9.82404E-01 -1.00000E+00 2.47704E-01 -2.97167E-01 14 -3.90445E-01 0.00000E+00 2.43790E-02 -1.73998E-02

[0103] (Table 2-2)

[0104] noodle 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

[0105] In Tables 2-1 and 2-2 above, when the lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, the curvature radius is set to a positive value, and when the lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side, the curvature radius is set to a negative value.

[0106] In addition, Tables 2-1 and 2-2 above show the aspherical coefficients A4, A6, A8, A10, A12, A14, and A16 when the aspherical shape of each surface is expressed by the following formula (Mathematical Formula 1). In the following formula, the sag (axis in the optical axis direction) is represented by Z, the height in the direction perpendicular to the optical axis (ray height) is represented by r, the conic coefficient is represented by K, and the inverse of the curvature radius is represented by c.

[0107] [Mathematical formula 1]

[0108]

[0109] Here, as described above, the maximum half-viewing angle ω of the wide-angle lens 1000 as a whole is 115 degrees, which satisfies the following condition 1-1:

[0110] 98°<ω<120°.

[0111] In condition 1-1, by setting the maximum half field angle ω to be greater than 98°, the maximum half field angle ω can be expanded. In addition, by setting the maximum half field angle ω to be less than 120°, it is possible to prevent the peripheral portion of the image from being darkened due to the light intensity ratio at the periphery of the lens 1000 being less than the light intensity ratio at the center, thereby expanding the maximum half field angle ω of the wide-angle lens 1000 while achieving miniaturization of the entire wide-angle lens 1000.

[0112] Furthermore, the focal length f of the wide-angle lens 1000 as a whole is 1.023 mm, and the entrance pupil diameter HEP is 0.507 mm. Therefore, the following conditions 1-2 are satisfied:

[0113] f / HEP<2.3.

[0114] In condition 1-2, by setting the ratio of the focal length f of the entire wide-angle lens 1000 to the entrance pupil diameter HEP to f / HEP<2.3, the brightness of the wide-angle lens 1000 can be ensured and the wide-angle lens 1000 can be applied to a high-pixel imaging element.

[0115] Furthermore, as can be seen from Table 1, the effective radius sd12 of the image-side lens surface of the first lens 110, i.e., the second surface 2, is 3.055 mm, and the curvature radius R12 of the second surface 2 of the first lens 110 is 3.350 mm. Therefore, the following conditions 1-3 are satisfied:

[0116] 0.890<sd12 / R12<0.970.

[0117] In condition 3, by setting the ratio of the effective radius sd12 of the second surface 2 of the first lens 110 to the radius of curvature R12 to be greater than 0.890, the half angle of view can be increased, and in particular, the half angle of view can be increased to 98° or greater. In addition, by setting the ratio of the effective radius sd12 of the second surface 2 of the first lens 110 to the radius of curvature R12 to be less than 0.970, the angle between the peripheral portion of the second surface 2 of the first lens 110 made of glass and the tangent line can be suppressed from being too small, thereby preventing the second surface 2 of the first lens 110 from being unable to be polished.

[0118] Furthermore, as shown in Table 1, the radius of curvature R11 of the object-side lens surface of the first lens 110, i.e., the first surface 1, is 11.420 mm, and the radius of curvature R12 of the image-side lens surface of the first lens 110, i.e., the second surface 2, is 3.350 mm. Therefore, the following conditions 1-4 are satisfied:

[0119] 1.300<(R11+R12) / (R11-R12)<1.900,

[0120] And also meet the following conditions 1-5:

[0121] 1.600<(R11+R12) / (R11-R12)<1.850.

[0122] In conditions 1-4, by setting (R11+R12) / (R11-R12) to be greater than 1.300, the radius of curvature R12 of the image-side lens surface of first lens 110, i.e., second surface 2, can be prevented from being too small, thereby facilitating molding of second surface 2 of first lens 110. Furthermore, the radius of curvature R11 of the object-side lens surface of first lens 110, i.e., first surface 1, can be prevented from being too large, thereby preventing the diameter of first lens 110 from being too large, thereby miniaturizing wide-angle lens 1000. Furthermore, by setting (R11+R12) / (R11-R12) to be less than 1.900, sufficient refractive power of first lens 110 can be ensured, thereby facilitating an increase in the maximum half-field angle ω of first lens 110. Furthermore, sufficient thickness of first lens 110 can be ensured to prevent damage to first lens 110 due to impact, etc.

[0123] Furthermore, in Condition 1-5, by further setting (R11+R12) / (R11-R12) to be greater than 1.600, the radius of curvature R12 of the image-side lens surface of the first lens 110, i.e., the second surface 2, can be further prevented from being too small, thereby facilitating molding of the second surface 2 of the first lens 110. Furthermore, the radius of curvature R11 of the object-side lens surface of the first lens 110, i.e., the first surface 1, can be further prevented from being too large, thereby further preventing the diameter of the first lens 110 from being too large, thereby further miniaturizing the wide-angle lens 1000. Furthermore, by further setting (R11+R12) / (R11-R12) to be less than 1.850, sufficient refractive power of the first lens 110 can be further ensured, thereby facilitating increasing the maximum half-angle of view ω of the first lens 110. Furthermore, sufficient thickness of the first lens 110 can be further ensured, further preventing damage to the first lens 110 due to impact, etc.

[0124] Furthermore, as can be seen from Table 1, the thickness T1 of the first lens 110 is 1.510 mm (the thickness T1 of the first lens 110 is defined as the distance between the object-side lens surface, i.e., the first surface 1, and the image-side lens surface, i.e., the second surface 2, of the first lens 110 in the optical axis direction), and the sag height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 11 is 1.974 mm. Therefore, the following conditions 1-6 are satisfied:

[0125] 0.700<T1 / Sag12<1.100.

[0126] Under conditions 1-6, by setting the ratio of the thickness T1 of the first lens 110 to the sagittal height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 110 to be greater than 0.700, it is possible to ensure that the first lens 110 has sufficient thickness to prevent the first lens 110 from being damaged by impact. In addition, by setting the ratio of the thickness T1 of the first lens 110 to the sagittal height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 110 to be less than 1.100, it is possible to prevent the first lens 110 from being too thick, thereby preventing the ideal negative optical power from being obtained.

[0127] Furthermore, in the wide-angle lens 1000 of this embodiment, the object-image distance d of the wide-angle lens 1000 is 13.611 mm, and the focal length f of the entire wide-angle lens 1000 is 1.023 mm. Therefore, the following conditions 1-7 are satisfied:

[0128] 11.000<d / f<15.000.

[0129] In conditions 1-7, by setting the ratio of the object-image distance d of the wide-angle lens 1000 to the focal length f of the entire wide-angle lens 1000 to be greater than 11.000, various aberrations can be easily corrected appropriately, thereby easily obtaining excellent optical characteristics; in addition, by setting the ratio of the object-image distance d of the wide-angle lens 1000 to the focal length f of the entire wide-angle lens 1000 to be less than 15.000, the wide-angle lens 1000 can be prevented from becoming too large while avoiding the entire length of the wide-angle lens 1000 from becoming too long.

[0130] In summary, in this embodiment, by constructing the wide-angle lens 1000 in the above manner, as shown in FIG. Figures 2A to 4L As shown, various aberrations such as curvature of field, chromatic aberration of magnification, and coma can be appropriately corrected, and miniaturization can be achieved while widening the maximum half angle of view ω.

[0131] (Implementation Method 2)

[0132] Figure 5 1 is an explanatory diagram showing a wide-angle lens according to Embodiment 2 of the present invention. Figure 6A 1 is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to the second embodiment of the present invention. Figure 6B 1 is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to the second embodiment of the present invention. Figure 7A 1 is an explanatory diagram showing vertical axial chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to Embodiment 2 of the present invention. Figure 7B 1 is an explanatory diagram showing spherical aberration (longitudinal aberration) of the wide-angle lens according to the second embodiment of the present invention. Figures 8A to 8L : is an explanatory diagram showing the lateral aberration of the wide-angle lens according to the second embodiment of the present invention. Figure 6A 、 Figure 6B 、 Figure 7A 、 Figure 7B 、 Figures 8A to 8L In the figure, the correlation curve of red light R (wavelength of 656nm) is marked with R, the correlation curve of green light G (wavelength of 588nm) is marked with G, and the correlation curve of blue light B (wavelength of 486nm) is marked with B. T is used to indicate correlation with the meridian plane, and S is used to indicate correlation with the sagittal plane. In addition, Figures 8A to 8L In the example, the maximum scale of the vertical axis is ±50.000 μm.

[0133] like Figure 5As shown, the wide-angle lens 1000 includes, arranged in order from the object side (L1 side), a first lens 110 (i.e., the first lens 110 is arranged at the position closest to the object side), a second lens 120 (i.e., the second lens 120 is arranged adjacent to the image side of the first lens 110), 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 cemented lens.

[0134] 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 optical power, whether they are glass lenses or plastic lenses, and whether the object-side and image-side surfaces 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 elaborated on here.

[0135] In addition, if Figure 5 As shown, similar to the first embodiment, a light shielding sheet 190 is provided between the second lens 120 and the fourth lens 130 , a filter 200 is arranged on the image side of the seventh lens 170 , and an imaging element 300 is arranged on the image side of the filter 200 .

[0136] In this embodiment, the focal length f (Effective Focal Length) of the entire lens system is 1.062 mm, the object-image distance d (Total Track) is 13.610 mm, the F value (Image Space F / #) is 2.02, the maximum half field of view (Max. Field of Angle) is 115 degrees, and the entrance pupil diameter HEP is 0.526 mm.

[0137] Table 3 shows the physical properties of each surface of the wide-angle lens 1000 according to this embodiment, and Tables 4-1 and 4-2 show the aspheric coefficients of each surface of the wide-angle lens 1000 according to this embodiment.

[0138] (Table 3)

[0139]

[0140] In Table 3 above, the units of the radius of curvature, thickness, focal length, effective radius, and sagittal height are mm, Nd is the refractive index for light of 587.56 nm, νd is the Abbe number, and * indicates an aspherical surface.

[0141] (Table 4-1)

[0142] noodle c(1 / radius of curvature) K A4 A6 3 2.19479E-02 0.00000E+00 -5.53459E-04 0.00000E+00 4 7.64121E-01 -1.00000E+00 4.76939E-02 1.87020E-03 5 -1.03144E-01 0.00000E+00 -4.63672E-04 2.39479E-02 6 -3.85243E-01 0.00000E+00 6.19526E-02 9.41258E-03 7 -2.07563E-01 0.00000E+00 8.01905E-02 -1.81445E-02 8 -4.45687E-01 0.00000E+00 5.32792E-02 -3.21513E-03 12 -1.43308E-01 0.00000E+00 2.59200E-02 -4.54679E-02 13 9.71678E-01 -1.00000E+00 2.67381E-01 -3.18917E-01 14 -4.11994E-01 0.00000E+00 2.93182E-02 -2.05884E-02

[0143] (Table 4-2)

[0144] noodle 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

[0145] In Tables 4-1 and 4-2 above, when the lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, the curvature radius is set to a positive value, and when the lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side, the curvature radius is set to a negative value.

[0146] In addition, in the above Table 4-1 and Table 2-2, the aspherical coefficients A4, A6, A8, A10, A12, A14, and A16 when the aspherical shape of each surface is expressed by the above Mathematical Formula 1 are shown.

[0147] Here, as described above, the maximum half-viewing angle ω of the wide-angle lens 1000 as a whole is 115 degrees, which satisfies the following condition 2-1:

[0148] 98°<ω<120°.

[0149] In condition 2-1, by setting the maximum half field angle ω to be greater than 98°, the maximum half field angle ω can be expanded. In addition, by setting the maximum half field angle ω to be less than 120°, it is possible to prevent the peripheral portion of the image from becoming darker due to the light intensity ratio at the periphery of the lens 1000 being less than the light intensity ratio at the center, thereby expanding the maximum half field angle ω of the wide-angle lens 1000 while achieving miniaturization of the entire wide-angle lens 1000.

[0150] Furthermore, the focal length f of the wide-angle lens 1000 as a whole is 1.023 mm, and the entrance pupil diameter HEP is 0.526 mm. Therefore, the following condition 2-2 is satisfied:

[0151] f / HEP<2.3.

[0152] In condition 2-2, by setting the ratio of the focal length f of the entire wide-angle lens 1000 to the entrance pupil diameter HEP to f / HEP<2.3, the brightness of the wide-angle lens 1000 can be ensured and the wide-angle lens 1000 can be applied to a high-pixel imaging element.

[0153] Furthermore, as shown in Table 3, the effective radius sd12 of the image-side lens surface of the first lens 110, i.e., the second surface 2, is 3.013 mm, and the curvature radius R12 of the second surface 2 of the first lens 110 is 3.310 mm. Therefore, the following conditions 2-3 are satisfied:

[0154] 0.890<sd12 / R12<0.970.

[0155] In condition 2-3, by setting the ratio of the effective radius sd12 of the second surface 2 of the first lens 110 to the radius of curvature R12 to be greater than 0.890, the half angle of view can be increased, and in particular, the half angle of view can be increased to 98° or greater. In addition, by setting the ratio of the effective radius sd12 of the second surface 2 of the first lens 110 to the radius of curvature R12 to be less than 0.970, the angle between the peripheral portion of the second surface 2 of the first lens 110 made of glass and the tangent line can be suppressed from being too small, thereby preventing the second surface 2 of the first lens 110 from being unable to be polished.

[0156] Furthermore, as shown in Table 3, the radius of curvature R11 of the object-side lens surface of the first lens 110, i.e., the first surface 1, is 11.363 mm, and the radius of curvature R12 of the image-side lens surface of the first lens 110, i.e., the second surface 2, is 3.310 mm. Therefore, the following conditions 2-4 are satisfied:

[0157] 1.300<(R11+R12) / (R11-R12)<1.900,

[0158] And also meet the following conditions 2-5:

[0159] 1.600<(R11+R12) / (R11-R12)<1.850.

[0160] In condition 2-4, by setting (R11+R12) / (R11-R12) to be greater than 1.300, the radius of curvature R12 of the image-side lens surface of first lens 110, i.e., second surface 2, can be prevented from being too small, thereby facilitating molding of second surface 2 of first lens 110. Furthermore, the radius of curvature R11 of the object-side lens surface of first lens 110, i.e., first surface 1, can be prevented from being too large, thereby preventing the diameter of first lens 110 from being too large, thereby miniaturizing wide-angle lens 1000. Furthermore, by setting (R11+R12) / (R11-R12) to be less than 1.900, sufficient refractive power of first lens 110 can be ensured, thereby facilitating an increase in the maximum half-field angle ω of first lens 110. Furthermore, sufficient thickness of first lens 110 can be ensured to prevent damage to first lens 110 due to impact, etc.

[0161] Furthermore, in condition 2-5, by further setting (R11+R12) / (R11-R12) to be greater than 1.600, the radius of curvature R12 of the image-side lens surface of the first lens 110, i.e., the second surface 2, can be further prevented from being too small, thereby facilitating molding of the second surface 2 of the first lens 110. Furthermore, the radius of curvature R11 of the object-side lens surface of the first lens 110, i.e., the first surface 1, can be further prevented from being too large, thereby further preventing the diameter of the first lens 110 from being too large, thereby further miniaturizing the wide-angle lens 1000. Furthermore, by further setting (R11+R12) / (R11-R12) to be less than 1.850, sufficient refractive power of the first lens 110 can be further ensured, thereby facilitating increasing the maximum half-angle of view ω of the first lens 110. Furthermore, sufficient thickness of the first lens 110 can be further ensured, further preventing damage to the first lens 110 due to impact, etc.

[0162] Furthermore, as shown in Table 3, the thickness T1 of the first lens 110 is 1.561 mm (the thickness T1 of the first lens 110 is defined as the distance between the object-side lens surface, i.e., the first surface 1, and the image-side lens surface, i.e., the second surface 2, of the first lens 110 in the optical axis direction), and the sag height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 11 is 1.940 mm. Therefore, the following conditions 2-6 are satisfied:

[0163] 0.700<T1 / Sag12<1.100.

[0164] Under condition 2-6, by setting the ratio of the thickness T1 of the first lens 110 to the sagittal height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 110 to be greater than 0.700, it is possible to ensure that the first lens 110 has sufficient thickness to prevent the first lens 110 from being damaged by impact. In addition, by setting the ratio of the thickness T1 of the first lens 110 to the sagittal height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 110 to be less than 1.100, it is possible to prevent the first lens 110 from being too thick, thereby preventing the ideal negative optical focal length from being obtained.

[0165] In addition, in the wide-angle lens 1000 of this embodiment, the object-image distance d of the wide-angle lens 1000 is 13.610 mm, and the focal length f of the entire wide-angle lens 1000 is 1.062 mm. Therefore, the following conditions 2-7 are satisfied:

[0166] 11.000<d / f<15.000.

[0167] In condition 2-7, by setting the ratio of the object-image distance d of the wide-angle lens 1000 to the focal length f of the entire wide-angle lens 1000 to be greater than 11.000, various aberrations can be easily corrected appropriately, thereby easily obtaining excellent optical characteristics; in addition, by setting the ratio of the object-image distance d of the wide-angle lens 1000 to the focal length f of the entire wide-angle lens 1000 to be less than 15.000, the wide-angle lens 1000 can be prevented from becoming too large while avoiding the entire length of the wide-angle lens 1000 from becoming too long.

[0168] In summary, in this embodiment, by constructing the wide-angle lens 1000 in the above manner, as shown in FIG. Figures 6A to 8L As shown, various aberrations such as curvature of field, chromatic aberration of magnification, and coma can be appropriately corrected, and miniaturization can be achieved while widening the maximum half angle of view ω.

[0169] (Implementation 3)

[0170] Figure 9 1 is an explanatory diagram showing a wide-angle lens according to Embodiment 3 of the present invention. Figure 10A 1 is an explanatory diagram showing field curvature and distortion of a wide-angle lens according to Embodiment 3 of the present invention. Figure 10B 1 is an explanatory diagram showing field curvature and distortion of a wide-angle lens according to Embodiment 3 of the present invention. Figure 11A 1 is an explanatory diagram showing vertical axial chromatic aberration (lateral chromatic aberration) of a wide-angle lens according to Embodiment 3 of the present invention. Figure 11B 1 is an explanatory diagram showing spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 3 of the present invention. Figures 12A to 12L : is an explanatory diagram showing the lateral aberration of the wide-angle lens according to the third embodiment of the present invention. Figure 10A 、 Figure 10B 、 Figure 11A 、 Figure 11B 、 Figures 12A to 12L In the figure, the correlation curve of red light R (wavelength of 656nm) is marked with R, the correlation curve of green light G (wavelength of 588nm) is marked with G, and the correlation curve of blue light B (wavelength of 486nm) is marked with B. T is used to indicate correlation with the meridian plane, and S is used to indicate correlation with the sagittal plane. In addition, Figures 12A to 12L In the example, the maximum scale of the vertical axis is ±50.000 μm.

[0171] like Figure 9As shown, the wide-angle lens 1000 includes, arranged in order from the object side (L1 side), a first lens 110 (i.e., the first lens 110 is arranged at the position closest to the object side), a second lens 120 (i.e., the second lens 120 is arranged adjacent to the image side of the first lens 110), 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 cemented lens.

[0172] 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 optical power, whether they are glass lenses or plastic lenses, and whether the object-side and image-side surfaces 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 elaborated on here.

[0173] In addition, if Figure 9 As shown, similar to the first embodiment, a light shielding sheet 190 is provided between the second lens 120 and the fourth lens 130 , a filter 200 is arranged on the image side of the seventh lens 170 , and an imaging element 300 is arranged on the image side of the filter 200 .

[0174] In this 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 of view (Max. Field of Angle) is 109 degrees, and the entrance pupil diameter HEP is 0.508 mm.

[0175] Table 5 shows the physical properties of each surface of the wide-angle lens 1000 according to this embodiment, and Tables 6-1 and 6-2 show the aspheric coefficient of each surface of the wide-angle lens 1000 according to this embodiment.

[0176] (Table 5)

[0177]

[0178] In Table 5 above, the units of the curvature radius, thickness, focal length, effective radius, and sagittal height are mm, Nd is the refractive index for light of 587.56 nm, νd is the Abbe number, and * indicates an aspherical surface.

[0179] (Table 6-1)

[0180] noodle c(1 / radius of curvature) K A4 A6 3 2.85248E-02 0.00000E+00 -7.73953E-04 -2.76248E-05 4 7.20578E-01 -1.00000E+00 1.69157E-02 2.83585E-02 5 -1.69997E-01 0.00000E+00 4.77013E-03 1.28269E-02 6 -4.12314E-01 0.00000E+00 4.38590E-02 3.36563E-03 7 -1.57044E-01 0.00000E+00 5.20793E-02 -9.74604E-03 8 -4.17218E-01 0.00000E+00 3.75209E-02 -1.18387E-03 12 -2.45256E-01 0.00000E+00 1.12258E-02 -2.18878E-02 13 9.36158E-01 -1.00000E+00 1.84892E-01 -2.17248E-01 14 -4.35910E-01 0.00000E+00 6.08264E-02 -6.37284E-02

[0181] (Table 6-2)

[0182] noodle 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

[0183] In Tables 6-1 and 6-2 above, when the lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, the curvature radius is set to a positive value, and when the lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side, the curvature radius is set to a negative value.

[0184] In addition, in the above Table 6-1 and Table 6-2, the aspherical coefficients A4, A6, A8, A10, A12, A14, and A16 when the aspherical shape of each surface is expressed by the above Mathematical Formula 1 are shown.

[0185] Here, as described above, the maximum half-viewing angle ω of the wide-angle lens 1000 as a whole is 109 degrees, which satisfies the following condition 3-1:

[0186] 98°<ω<120°.

[0187] In condition 3-1, by setting the maximum half field angle ω to be greater than 98°, the maximum half field angle ω can be expanded. In addition, by setting the maximum half field angle ω to be less than 120°, it is possible to prevent the peripheral portion of the image from becoming darker due to the light intensity ratio at the periphery of the lens 1000 being less than the light intensity ratio at the center, thereby expanding the maximum half field angle ω of the wide-angle lens 1000 while achieving miniaturization of the entire wide-angle lens 1000.

[0188] Furthermore, the focal length f of the wide-angle lens 1000 as a whole is 1.026 mm, and the entrance pupil diameter HEP is 0.508 mm. Therefore, the following condition 3-2 is satisfied:

[0189] f / HEP<2.3.

[0190] In condition 3-2, by setting the ratio of the focal length f of the entire wide-angle lens 1000 to the entrance pupil diameter HEP to f / HEP<2.3, the brightness of the wide-angle lens 1000 can be ensured and the wide-angle lens 1000 can be applied to a high-pixel imaging element.

[0191] Furthermore, as shown in Table 5, the effective radius sd12 of the image-side lens surface of the first lens 110, i.e., the second surface 2, is 2.863 mm, and the curvature radius R12 of the second surface 2 of the first lens 110 is 3.204 mm. Therefore, the following condition 3-3 is satisfied:

[0192] 0.890<sd12 / R12<0.970.

[0193] In condition 3-3, by setting the ratio of the effective radius sd12 of the second surface 2 of the first lens 110 to the radius of curvature R12 to be greater than 0.890, the half angle of view can be increased, and in particular, the half angle of view can be increased to 98° or greater. In addition, by setting the ratio of the effective radius sd12 of the second surface 2 of the first lens 110 to the radius of curvature R12 to be less than 0.970, the angle between the peripheral portion of the second surface 2 of the first lens 110 made of glass and the tangent line can be suppressed from being too small, thereby preventing the second surface 2 of the first lens 110 from being unable to be polished.

[0194] Furthermore, as shown in Table 5, the radius of curvature R11 of the object-side lens surface of the first lens element 110, i.e., the first surface 1, is 11.171 mm, and the radius of curvature R12 of the image-side lens surface of the first lens element 110, i.e., the second surface 2, is 3.204 mm. Therefore, the following conditions 3-4 are satisfied:

[0195] 1.300<(R11+R12) / (R11-R12)<1.900,

[0196] And also meet the following conditions 3-5:

[0197] 1.600<(R11+R12) / (R11-R12)<1.850.

[0198] In condition 3-4, by setting (R11+R12) / (R11-R12) to be greater than 1.300, the radius of curvature R12 of the image-side lens surface of first lens 110, i.e., second surface 2, can be prevented from being too small, thereby facilitating molding of second surface 2 of first lens 110. Furthermore, the radius of curvature R11 of the object-side lens surface of first lens 110, i.e., first surface 1, can be prevented from being too large, thereby preventing the diameter of first lens 110 from being too large, thereby miniaturizing wide-angle lens 1000. Furthermore, by setting (R11+R12) / (R11-R12) to be less than 1.900, sufficient refractive power of first lens 110 can be ensured, thereby facilitating an increase in the maximum half-angle of view ω of first lens 110. Furthermore, sufficient thickness of first lens 110 can be ensured to prevent damage to first lens 110 due to impact, etc.

[0199] Furthermore, in Condition 3-5, by further setting (R11+R12) / (R11-R12) to be greater than 1.600, the radius of curvature R12 of the image-side lens surface of the first lens 110, i.e., the second surface 2, can be further prevented from being too small, thereby facilitating molding of the second surface 2 of the first lens 110. Furthermore, the radius of curvature R11 of the object-side lens surface of the first lens 110, i.e., the first surface 1, can be further prevented from being too large, thereby further preventing the diameter of the first lens 110 from being too large, thereby further miniaturizing the wide-angle lens 1000. Furthermore, by further setting (R11+R12) / (R11-R12) to be less than 1.850, sufficient refractive power of the first lens 110 can be further ensured, thereby facilitating increasing the maximum half-angle of view ω of the first lens 110. Furthermore, sufficient thickness of the first lens 110 can be further ensured, further preventing damage to the first lens 110 due to impact, etc.

[0200] Furthermore, as shown in Table 5, the thickness T1 of the first lens 110 is 1.300 mm (the thickness T1 of the first lens 110 is defined as the distance between the object-side lens surface, i.e., the first surface 1, and the image-side lens surface, i.e., the second surface 2, of the first lens 110 in the optical axis direction), and the sag height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 11 is 1.766 mm. Therefore, the following conditions 3-6 are satisfied:

[0201] 0.700<T1 / Sag12<1.100.

[0202] Under condition 3-6, by setting the ratio of the thickness T1 of the first lens 110 to the sagittal height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 110 to be greater than 0.700, it is possible to ensure that the first lens 110 has sufficient thickness to prevent the first lens 110 from being damaged by impact. In addition, by setting the ratio of the thickness T1 of the first lens 110 to the sagittal height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 110 to be less than 1.100, it is possible to prevent the first lens 110 from being too thick, thereby preventing the ideal negative optical focal length from being obtained.

[0203] Furthermore, in the wide-angle lens 1000 of this embodiment, the object-image distance d of the wide-angle lens 1000 is 13.403 mm, and the focal length f of the entire wide-angle lens 1000 is 1.026 mm. Therefore, the following conditions 3-7 are satisfied:

[0204] 11.000<d / f<15.000.

[0205] In condition 3-7, by setting the ratio of the object-image distance d of the wide-angle lens 1000 to the focal length f of the entire wide-angle lens 1000 to be greater than 11.000, various aberrations can be easily corrected appropriately, thereby easily obtaining excellent optical characteristics; in addition, by setting the ratio of the object-image distance d of the wide-angle lens 1000 to the focal length f of the entire wide-angle lens 1000 to be less than 15.000, the wide-angle lens 1000 can be prevented from becoming too large while avoiding the entire length of the wide-angle lens 1000 from becoming too long.

[0206] In summary, in this embodiment, by constructing the wide-angle lens 1000 in the above manner, as shown in FIG. Figures 10A to 12L As shown, various aberrations such as curvature of field, chromatic aberration of magnification, and coma can be appropriately corrected, and miniaturization can be achieved while widening the maximum half angle of view ω.

[0207] (Implementation 4)

[0208] Figure 13 1 is an explanatory diagram showing a wide-angle lens according to a fourth embodiment of the present invention. Figure 14A 1 is an explanatory diagram showing field curvature and distortion of a wide-angle lens according to a fourth embodiment of the present invention. Figure 14B 1 is an explanatory diagram showing field curvature and distortion of a wide-angle lens according to a fourth embodiment of the present invention. Figure 15A 1 is an explanatory diagram showing vertical axial chromatic aberration (lateral chromatic aberration) of a wide-angle lens according to Embodiment 4 of the present invention. Figure 15B 1 is an explanatory diagram showing spherical aberration (longitudinal aberration) of a wide-angle lens according to Embodiment 4 of the present invention. Figures 16A to 16L : is an explanatory diagram showing the lateral aberration of the wide-angle lens according to the fourth embodiment of the present invention. Figure 14A 、 Figure 14B 、 Figure 15A 、 Figure 15B 、 Figures 16A to 16L In the figure, the correlation curve of red light R (wavelength of 656nm) is marked with R, the correlation curve of green light G (wavelength of 588nm) is marked with G, and the correlation curve of blue light B (wavelength of 486nm) is marked with B. T is used to indicate correlation with the meridian plane, and S is used to indicate correlation with the sagittal plane. In addition, Figures 16A to 16L In the example, the maximum scale of the vertical axis is ±50.000 μm.

[0209] like Figure 13As shown, the wide-angle lens 1000 includes, arranged in order from the object side (L1 side), a first lens 110 (i.e., the first lens 110 is arranged at the position closest to the object side), a second lens 120 (i.e., the second lens 120 is arranged adjacent to the image side of the first lens 110), 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 cemented lens.

[0210] 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 optical power, whether they are glass lenses or plastic lenses, and whether the object-side and image-side surfaces 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 elaborated on here.

[0211] In addition, if Figure 13 As shown, similar to the first embodiment, a light shielding sheet 190 is provided between the second lens 120 and the fourth lens 130 , a filter 200 is arranged on the image side of the seventh lens 170 , and an imaging element 300 is arranged on the image side of the filter 200 .

[0212] In this embodiment, the focal length f (Effective Focal Length) of the entire lens system is 1.011 mm, the object-image distance d (Total Track) is 13.404 mm, the F value (Image Space F / #) is 2.03, the maximum half field of view (Max. Field of Angle) is 109 degrees, and the entrance pupil diameter HEP is 0.498 mm.

[0213] Table 7 shows the physical properties of each surface of the wide-angle lens 1000 according to this embodiment, and Tables 8-1 and 8-2 show the aspheric coefficient of each surface of the wide-angle lens 1000 according to this embodiment.

[0214] (Table 7)

[0215]

[0216] In Table 7 above, the units of the curvature radius, thickness, focal length, effective radius, and sagittal height are mm, Nd is the refractive index for light of 587.56 nm, νd is the Abbe number, and * indicates an aspherical surface.

[0217] (Table 8-1)

[0218] noodle c(1 / radius of curvature) K A4 A6 3 4.33971E-02 0.00000E+00 -6.82448E-03 3.73911E-03 4 7.74346E-01 -5.39587E+00 2.32631E-01 -1.17492E-01 5 -7.38477E-02 0.00000E+00 2.29113E-02 4.37979E-03 6 -3.05528E-01 0.00000E+00 4.74057E-02 -5.28192E-03 7 -4.98442E-02 0.00000E+00 4.27102E-02 -4.22032E-04 8 -3.13660E-01 0.00000E+00 3.38907E-02 3.26534E-03 12 -2.41789E-01 0.00000E+00 -3.09436E-02 3.41185E-02 13 1.05668E+00 -1.00000E+00 5.66189E-04 -1.14232E-02 14 -4.86390E-01 0.00000E+00 7.16605E-02 -6.17165E-02

[0219] (Table 8-2)

[0220] noodle 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

[0221] In Tables 8-1 and 8-2 above, when the lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, the curvature radius is set to a positive value, and when the lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side, the curvature radius is set to a negative value.

[0222] In addition, in the above Table 8-1 and Table 8-2, the aspherical coefficients A4, A6, A8, A10, A12, A14, and A16 when the aspherical shape of each surface is expressed by the above Mathematical Formula 1 are shown.

[0223] Here, as described above, the maximum half-viewing angle ω of the wide-angle lens 1000 as a whole is 109 degrees, which satisfies the following condition 4-1:

[0224] 98°<ω<120°.

[0225] In condition 4-1, by setting the maximum half field angle ω to be greater than 98°, the maximum half field angle ω can be expanded. In addition, by setting the maximum half field angle ω to be less than 120°, it is possible to prevent the peripheral portion of the image from becoming darker due to the light intensity ratio at the periphery of the lens 1000 being less than the light intensity ratio at the center, thereby expanding the maximum half field angle ω of the wide-angle lens 1000 while achieving miniaturization of the entire wide-angle lens 1000.

[0226] Furthermore, the focal length f of the wide-angle lens 1000 as a whole is 1.011 mm, and the entrance pupil diameter HEP is 0.498 mm. Therefore, the following condition 4-2 is satisfied:

[0227] f / HEP<2.3.

[0228] In condition 4-2, by setting the ratio of the focal length f of the entire wide-angle lens 1000 to the entrance pupil diameter HEP to f / HEP<2.3, the brightness of the wide-angle lens 1000 can be ensured and the wide-angle lens 1000 can be used in a high-pixel imaging element.

[0229] Furthermore, as shown in Table 7, the effective radius sd12 of the image-side lens surface of the first lens 110, i.e., the second surface 2, is 2.623 mm, and the curvature radius R12 of the second surface 2 of the first lens 110 is 2.910 mm. Therefore, the following condition 4-3 is satisfied:

[0230] 0.890<sd12 / R12<0.970.

[0231] In condition 4-3, by setting the ratio of the effective radius sd12 of the second surface 2 of the first lens 110 to the radius of curvature R12 to be greater than 0.890, the half angle of view can be increased, and in particular, the half angle of view can be increased to 98° or greater. In addition, by setting the ratio of the effective radius sd12 of the second surface 2 of the first lens 110 to the radius of curvature R12 to be less than 0.970, the angle between the peripheral portion of the second surface 2 of the first lens 110 made of glass and the tangent line can be suppressed from being too small, thereby preventing the second surface 2 of the first lens 110 from being unable to be polished.

[0232] Furthermore, as shown in Table 7, the radius of curvature R11 of the object-side lens surface of the first lens 110, i.e., the first surface 1, is 11.850 mm, and the radius of curvature R12 of the image-side lens surface of the first lens 110, i.e., the second surface 2, is 2.910 mm. Therefore, the following condition 4-4 is satisfied:

[0233] 1.300<(R11+R12) / (R11-R12)<1.900,

[0234] And also meet the following conditions 4-5:

[0235] 1.600<(R11+R12) / (R11-R12)<1.850.

[0236] In condition 4-4, by setting (R11+R12) / (R11-R12) to be greater than 1.300, the radius of curvature R12 of the image-side lens surface of first lens 110, i.e., second surface 2, can be prevented from being too small, thereby facilitating molding of second surface 2 of first lens 110. Furthermore, the radius of curvature R11 of the object-side lens surface of first lens 110, i.e., first surface 1, can be prevented from being too large, thereby preventing the diameter of first lens 110 from being too large, thereby miniaturizing wide-angle lens 1000. Furthermore, by setting (R11+R12) / (R11-R12) to be less than 1.900, sufficient refractive power of first lens 110 can be ensured, thereby facilitating an increase in the maximum half-field angle ω of first lens 110. Furthermore, sufficient thickness of first lens 110 can be ensured to prevent damage to first lens 110 due to impact, etc.

[0237] Furthermore, in Condition 4-5, by further setting (R11+R12) / (R11-R12) to be greater than 1.600, the radius of curvature R12 of the image-side lens surface of the first lens 110, i.e., the second surface 2, can be further prevented from being too small, thereby facilitating molding of the second surface 2 of the first lens 110. Furthermore, the radius of curvature R11 of the object-side lens surface of the first lens 110, i.e., the first surface 1, can be further prevented from being too large, thereby further preventing the diameter of the first lens 110 from being too large, thereby further miniaturizing the wide-angle lens 1000. Furthermore, by further setting (R11+R12) / (R11-R12) to be less than 1.850, sufficient refractive power of the first lens 110 can be further ensured, thereby facilitating increasing the maximum half-angle of view ω of the first lens 110. Furthermore, sufficient thickness of the first lens 110 can be further ensured, further preventing damage to the first lens 110 due to impact, etc.

[0238] Furthermore, as shown in Table 7, the thickness T1 of the first lens 110 is 1.800 mm (the thickness T1 of the first lens 110 is defined as the distance between the object-side lens surface, i.e., the first surface 1, and the image-side lens surface, i.e., the second surface 2, of the first lens 110 in the optical axis direction), and the sag height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 11 is 1.649 mm. Therefore, the following conditions 4-6 are satisfied:

[0239] 0.700<T1 / Sag12<1.100.

[0240] Under conditions 4-6, by setting the ratio of the thickness T1 of the first lens 110 to the sagittal height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 110 to be greater than 0.700, it is possible to ensure that the first lens 110 has a sufficient thickness to prevent the first lens 110 from being damaged by impact. In addition, by setting the ratio of the thickness T1 of the first lens 110 to the sagittal height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 110 to be less than 1.100, it is possible to prevent the first lens 110 from being too thick, thereby preventing the ideal negative optical focal length from being obtained.

[0241] Furthermore, in the wide-angle lens 1000 of this embodiment, the object-image distance d of the wide-angle lens 1000 is 13.404 mm, and the focal length f of the entire wide-angle lens 1000 is 1.011 mm. Therefore, the following conditions 4-7 are satisfied:

[0242] 11.000<d / f<15.000.

[0243] In conditions 4-7, by setting the ratio of the object-image distance d of the wide-angle lens 1000 to the focal length f of the entire wide-angle lens 1000 to be greater than 11.000, various aberrations can be easily corrected appropriately, thereby easily obtaining excellent optical characteristics; in addition, by setting the ratio of the object-image distance d of the wide-angle lens 1000 to the focal length f of the entire wide-angle lens 1000 to be less than 15.000, the wide-angle lens 1000 can be prevented from becoming too large while avoiding the entire length of the wide-angle lens 1000 from becoming too long.

[0244] In summary, in this embodiment, by constructing the wide-angle lens 1000 in the above manner, as shown in FIG. Figures 14A to 16L As shown, various aberrations such as curvature of field, chromatic aberration of magnification, and coma can be appropriately corrected, and miniaturization can be achieved while widening the maximum half angle of view ω.

[0245] (Implementation 5)

[0246] Figure 17 1 is an explanatory diagram showing a wide-angle lens according to a fifth embodiment of the present invention. Figure 18A 1 is an explanatory diagram showing field curvature and distortion of a wide-angle lens according to Embodiment 5 of the present invention. Figure 18B 1 is an explanatory diagram showing field curvature and distortion of a wide-angle lens according to Embodiment 5 of the present invention. Figure 19A 1 is an explanatory diagram showing vertical axial chromatic aberration (lateral chromatic aberration) of a wide-angle lens according to Embodiment 5 of the present invention. Figure 19B 1 is an explanatory diagram showing spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 5 of the present invention. Figures 20A to 20L : is an explanatory diagram showing the lateral aberration of the wide-angle lens according to the fifth embodiment of the present invention. Figure 18A 、 Figure 18B 、 Figure 19A 、 Figure 19B 、 Figures 20A to 20L In the figure, the correlation curve of red light R (wavelength of 656nm) is marked with R, the correlation curve of green light G (wavelength of 588nm) is marked with G, and the correlation curve of blue light B (wavelength of 486nm) is marked with B. T is used to indicate correlation with the meridian plane, and S is used to indicate correlation with the sagittal plane. In addition, Figures 20A to 20L In the example, the maximum scale of the vertical axis is ±50.000 μm.

[0247] like Figure 17As shown, the wide-angle lens 1000 includes, arranged in order from the object side (L1 side), a first lens 110 (i.e., the first lens 110 is arranged at the position closest to the object side), a second lens 120 (i.e., the second lens 120 is arranged adjacent to the image side of the first lens 110), 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 cemented lens.

[0248] 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 optical power, whether they are glass lenses or plastic lenses, and whether the object-side and image-side surfaces 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 elaborated on here.

[0249] In addition, if Figure 17 As shown, similar to the first embodiment, a light shielding sheet 190 is provided between the second lens 120 and the fourth lens 130 , a filter 200 is arranged on the image side of the seventh lens 170 , and an imaging element 300 is arranged on the image side of the filter 200 .

[0250] In this embodiment, the focal length f (Effective Focal Length) of the entire lens system is 1.021 mm, the object-image distance d (Total Track) is 13.398 mm, the F value (Image Space F / #) is 2, the maximum half field of view (Max. Field of Angle) is 108 degrees, and the entrance pupil diameter HEP is 0.511 mm.

[0251] Table 9 shows the physical properties of each surface of the wide-angle lens 1000 according to this embodiment, and Tables 10-1 and 10-2 show the aspheric coefficient of each surface of the wide-angle lens 1000 according to this embodiment.

[0252] (Table 9)

[0253]

[0254] In Table 9 above, the units of the radius of curvature, thickness, focal length, effective radius, and sagittal height are mm, Nd is the refractive index for light of 587.56 nm, νd is the Abbe number, and * indicates an aspherical surface.

[0255] (Table 10-1)

[0256] noodle c(1 / radius of curvature) K A4 A6 3 4.73738E-02 0.00000E+00 -5.16461E-03 2.97096E-03 4 8.15727E-01 -3.85594E+00 2.02517E-01 -7.83664E-02 5 -2.43593E-02 0.00000E+00 7.18080E-04 1.54312E-02 6 -2.77185E-01 0.00000E+00 1.27000E-02 1.84355E-02 7 2.82614E-02 0.00000E+00 1.29430E-02 2.83444E-02 8 -2.75058E-01 0.00000E+00 5.20665E-03 2.87756E-02 12 -1.74511E-01 0.00000E+00 -2.22912E-02 -2.24026E-04 13 1.09890E+00 -1.00000E+00 5.45916E-02 -8.55229E-02 14 -4.33708E-01 0.00000E+00 5.56964E-02 -4.87201E-02

[0257] (Table 10-2)

[0258] noodle 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

[0259] In Tables 10-1 and 10-2 above, when the lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, the curvature radius is set to a positive value, and when the lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side, the curvature radius is set to a negative value.

[0260] In addition, in the above Table 10-1 and Table 10-2, the aspherical coefficients A4, A6, A8, A10, A12, A14, and A16 when the aspherical shape of each surface is represented by the above Mathematical Formula 1 are shown.

[0261] Here, as described above, the maximum half-field angle ω of the wide-angle lens 1000 as a whole is 108 degrees, which satisfies the following condition 5-1:

[0262] 98°<ω<120°.

[0263] In condition 5-1, by setting the maximum half field angle ω to be greater than 98°, the maximum half field angle ω can be expanded. In addition, by setting the maximum half field angle ω to be less than 120°, it is possible to prevent the peripheral portion of the image from becoming darker due to the light intensity ratio at the periphery of the lens 1000 being less than the light intensity ratio at the center, thereby expanding the maximum half field angle ω of the wide-angle lens 1000 while achieving miniaturization of the entire wide-angle lens 1000.

[0264] Furthermore, the focal length f of the wide-angle lens 1000 as a whole is 1.021 mm, and the entrance pupil diameter HEP is 0.511 mm. Therefore, the following condition 5-2 is satisfied:

[0265] f / HEP<2.3.

[0266] In condition 5-2, by setting the ratio of the focal length f of the entire wide-angle lens 1000 to the entrance pupil diameter HEP to f / HEP<2.3, the brightness of the wide-angle lens 1000 can be ensured and the wide-angle lens 1000 can be used in a high-pixel imaging element.

[0267] Furthermore, as shown in Table 9, the effective radius sd12 of the image-side lens surface of the first lens 110, i.e., the second surface 2, is 2.623 mm, and the radius of curvature R12 of the second surface 2 of the first lens 110 is 2.810 mm. Therefore, the following condition 5-3 is satisfied:

[0268] 0.890<sd12 / R12<0.970.

[0269] In condition 5-3, by setting the ratio of the effective radius sd12 of the second surface 2 of the first lens 110 to the radius of curvature R12 to be greater than 0.890, the half angle of view can be increased, and in particular, the half angle of view can be increased to 98° or greater. In addition, by setting the ratio of the effective radius sd12 of the second surface 2 of the first lens 110 to the radius of curvature R12 to be less than 0.970, the angle between the peripheral portion of the second surface 2 of the first lens 110 made of glass and the tangent line can be suppressed from being too small, thereby preventing the second surface 2 of the first lens 110 from being unable to be polished.

[0270] Furthermore, as shown in Table 9, the radius of curvature R11 of the object-side lens surface of the first lens 110, i.e., the first surface 1, is 11.850 mm, and the radius of curvature R12 of the image-side lens surface of the first lens 110, i.e., the second surface 2, is 2.810 mm. Therefore, the following condition 5-4 is satisfied:

[0271] 1.300<(R11+R12) / (R11-R12)<1.900,

[0272] And also meet the following conditions 5-5:

[0273] 1.600<(R11+R12) / (R11-R12)<1.850.

[0274] In condition 5-4, by setting (R11+R12) / (R11-R12) to be greater than 1.300, the radius of curvature R12 of the image-side lens surface of first lens 110, i.e., second surface 2, can be prevented from being too small, thereby facilitating molding of second surface 2 of first lens 110. Furthermore, the radius of curvature R11 of the object-side lens surface of first lens 110, i.e., first surface 1, can be prevented from being too large, thereby preventing the diameter of first lens 110 from being too large, thereby miniaturizing wide-angle lens 1000. Furthermore, by setting (R11+R12) / (R11-R12) to be less than 1.900, sufficient refractive power of first lens 110 can be ensured, thereby facilitating an increase in the maximum half-field angle ω of first lens 110. Furthermore, sufficient thickness of first lens 110 can be ensured to prevent damage to first lens 110 due to impact, etc.

[0275] Furthermore, in Condition 5-5, by further setting (R11+R12) / (R11-R12) to be greater than 1.600, the radius of curvature R12 of the image-side lens surface of the first lens 110, i.e., the second surface 2, can be further prevented from being too small, thereby facilitating molding of the second surface 2 of the first lens 110. Furthermore, the radius of curvature R11 of the object-side lens surface of the first lens 110, i.e., the first surface 1, can be further prevented from being too large, thereby further preventing the diameter of the first lens 110 from being too large, thereby further miniaturizing the wide-angle lens 1000. Furthermore, by further setting (R11+R12) / (R11-R12) to be less than 1.850, sufficient refractive power of the first lens 110 can be further ensured, thereby facilitating increasing the maximum half-angle of view ω of the first lens 110. Furthermore, sufficient thickness of the first lens 110 can be further ensured, further preventing damage to the first lens 110 due to impact, etc.

[0276] Furthermore, as shown in Table 9, the thickness T1 of the first lens 110 is 1.800 mm (the thickness T1 of the first lens 110 is defined as the distance between the object-side lens surface, i.e., the first surface 1, and the image-side lens surface, i.e., the second surface 2, of the first lens 110 in the optical axis direction), and the sag height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 11 is 1.802 mm. Therefore, the following conditions 5-6 are satisfied:

[0277] 0.700<T1 / Sag12<1.100.

[0278] Under conditions 5-6, by setting the ratio of the thickness T1 of the first lens 110 to the sagittal height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 110 to be greater than 0.700, it is possible to ensure that the first lens 110 has sufficient thickness to prevent the first lens 110 from being damaged by impact. In addition, by setting the ratio of the thickness T1 of the first lens 110 to the sagittal height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 110 to be less than 1.100, it is possible to prevent the first lens 110 from being too thick, thereby preventing the ideal negative optical focal length from being obtained.

[0279] Furthermore, in the wide-angle lens 1000 of this embodiment, the object-image distance d of the wide-angle lens 1000 is 13.398 mm, and the focal length f of the entire wide-angle lens 1000 is 1.021 mm. Therefore, the following conditions 5-7 are satisfied:

[0280] 11.000<d / f<15.000.

[0281] In conditions 5-7, by setting the ratio of the object-image distance d of the wide-angle lens 1000 to the focal length f of the entire wide-angle lens 1000 to be greater than 11.000, various aberrations can be appropriately corrected, thereby easily obtaining excellent optical characteristics; in addition, by setting the ratio of the object-image distance d of the wide-angle lens 1000 to the focal length f of the entire wide-angle lens 1000 to be less than 15.000, the wide-angle lens 1000 can be prevented from becoming too large while avoiding the entire length of the wide-angle lens 1000 from becoming too long.

[0282] In summary, in this embodiment, by constructing the wide-angle lens 1000 in the above manner, as shown in FIG. Figures 18A to 20L As shown, various aberrations such as curvature of field, chromatic aberration of magnification, and coma can be appropriately corrected, and miniaturization can be achieved while widening the maximum half angle of view ω.

[0283] (Implementation 6)

[0284] Figure 21 1 is an explanatory diagram showing a wide-angle lens according to a sixth embodiment of the present invention. Figure 22A 1 is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to the sixth embodiment of the present invention. Figure 22B 1 is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to the sixth embodiment of the present invention. Figure 23A 1 is an explanatory diagram showing vertical axial chromatic aberration (lateral chromatic aberration) of a wide-angle lens according to Embodiment 6 of the present invention. Figure 23B 1 is an explanatory diagram showing spherical aberration (longitudinal aberration) of a wide-angle lens according to Embodiment 6 of the present invention. Figures 24A to 24L : is an explanatory diagram showing the lateral aberration of the wide-angle lens according to the sixth embodiment of the present invention. Figure 22A 、 Figure 22B 、 Figure 23A 、 Figure 23B 、 Figures 24A to 24L In the figure, the correlation curve of red light R (wavelength of 656nm) is marked with R, the correlation curve of green light G (wavelength of 588nm) is marked with G, and the correlation curve of blue light B (wavelength of 486nm) is marked with B. T is used to indicate correlation with the meridian plane, and S is used to indicate correlation with the sagittal plane. In addition, Figures 24A to 24L In the example, the maximum scale of the vertical axis is ±50.000 μm.

[0285] like Figure 21As shown, the wide-angle lens 1000 includes, arranged in order from the object side (L1 side), a first lens 110 (i.e., the first lens 110 is arranged at the position closest to the object side), a second lens 120 (i.e., the second lens 120 is arranged adjacent to the image side of the first lens 110), 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 cemented lens.

[0286] 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 optical power, whether they are glass lenses or plastic lenses, and whether the object-side and image-side surfaces 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 elaborated on here.

[0287] In addition, if Figure 21 As shown, similar to the first embodiment, a light shielding sheet 190 is provided between the second lens 120 and the fourth lens 130 , a filter 200 is arranged on the image side of the seventh lens 170 , and an imaging element 300 is arranged on the image side of the filter 200 .

[0288] In this embodiment, the focal length f (Effective Focal Length) of the entire lens system is 1.018 mm, the object-image distance d (Total Track) is 13.383 mm, the F value (Image Space F / #) is 2, the maximum half field of view (Max. Field of Angle) is 108 degrees, and the entrance pupil diameter HEP is 0.509 mm.

[0289] Table 11 shows the physical properties of each surface of the wide-angle lens 1000 according to this embodiment, and Tables 12-1 and 12-2 show the aspheric coefficient of each surface of the wide-angle lens 1000 according to this embodiment.

[0290] (Table 11)

[0291]

[0292] In Table 11 above, the units of the radius of curvature, thickness, focal length, effective radius, and sagittal height are mm, Nd is the refractive index for light of 587.56 nm, νd is the Abbe number, and * indicates an aspherical surface.

[0293] (Table 12-1)

[0294] noodle c(1 / radius of curvature) K A4 A6 3 1.09306E-01 0.00000E+00 -4.51092E-03 2.92728E-03 4 8.39842E-01 -3.71100E+00 2.15910E-01 -7.58275E-02 5 -7.07214E-02 0.00000E+00 -5.47555E-03 1.09203E-02 6 -2.61938E-01 0.00000E+00 1.43606E-02 2.26240E-02 7 -4.49438E-02 0.00000E+00 1.40010E-02 4.01310E-02 8 -3.68664E-01 0.00000E+00 1.66786E-02 2.21644E-02 12 -2.77778E-01 0.00000E+00 -2.23667E-02 7.48072E-03 13 1.03842E+00 -1.00000E+00 4.72309E-02 -6.05266E-02 14 -4.67071E-01 0.00000E+00 5.78738E-02 -4.73130E-02

[0295] (Table 12-2)

[0296] noodle 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

[0297] In Tables 12-1 and 12-2 above, when the lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, the curvature radius is set to a positive value, and when the lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side, the curvature radius is set to a negative value.

[0298] In addition, in the above Table 12-1 and Table 12-2, the aspherical coefficients A4, A6, A8, A10, A12, A14, and A16 when the aspherical shape of each surface is expressed by the above Mathematical Formula 1 are shown.

[0299] Here, as described above, the maximum half-viewing angle ω of the wide-angle lens 1000 as a whole is 108 degrees, which satisfies the following condition 6-1:

[0300] 98°<ω<120°.

[0301] In condition 6-1, by setting the maximum half field angle ω to be greater than 98°, the maximum half field angle ω can be expanded. In addition, by setting the maximum half field angle ω to be less than 120°, it is possible to prevent the peripheral portion of the image from becoming darker due to the light intensity ratio at the periphery of the lens 1000 being less than the light intensity ratio at the center, thereby expanding the maximum half field angle ω of the wide-angle lens 1000 while achieving miniaturization of the entire wide-angle lens 1000.

[0302] Furthermore, the focal length f of the wide-angle lens 1000 as a whole is 1.018 mm, and the entrance pupil diameter HEP is 0.509 mm. Therefore, the following condition 6-2 is satisfied:

[0303] f / HEP<2.3.

[0304] In condition 6-2, by setting the ratio of the focal length f of the entire wide-angle lens 1000 to the entrance pupil diameter HEP to f / HEP<2.3, the brightness of the wide-angle lens 1000 can be ensured and the wide-angle lens 1000 can be used in a high-pixel imaging element.

[0305] Furthermore, as shown in Table 11, the effective radius sd12 of the image-side lens surface of the first lens 110, i.e., the second surface 2, is 2.691 mm, and the radius of curvature R12 of the second surface 2 of the first lens 110 is 2.910 mm. Therefore, the following condition 6-3 is satisfied:

[0306] 0.890<sd12 / R12<0.970.

[0307] In condition 6-3, by setting the ratio of the effective radius sd12 of the second surface 2 of the first lens 110 to the radius of curvature R12 to be greater than 0.890, the half angle of view can be increased, and in particular, the half angle of view can be increased to 98° or greater. In addition, by setting the ratio of the effective radius sd12 of the second surface 2 of the first lens 110 to the radius of curvature R12 to be less than 0.970, the angle between the peripheral portion of the second surface 2 of the first lens 110 made of glass and the tangent line can be suppressed from being too small, thereby preventing the second surface 2 of the first lens 110 from being unable to be polished.

[0308] Furthermore, as can be seen from Table 11, the radius of curvature R11 of the object-side lens surface of the first lens 110, i.e., the first surface 1, is 12.500 mm, and the radius of curvature R12 of the image-side lens surface of the first lens 110, i.e., the second surface 2, is 2.910 mm. Therefore, the following condition 6-4 is satisfied:

[0309] 1.300<(R11+R12) / (R11-R12)<1.900,

[0310] And also meet the following conditions 6-5:

[0311] 1.600<(R11+R12) / (R11-R12)<1.850.

[0312] In condition 6-4, by setting (R11+R12) / (R11-R12) to be greater than 1.300, the radius of curvature R12 of the image-side lens surface of first lens 110, i.e., second surface 2, can be prevented from being too small, thereby facilitating molding of second surface 2 of first lens 110. Furthermore, the radius of curvature R11 of the object-side lens surface of first lens 110, i.e., first surface 1, can be prevented from being too large, thereby preventing the diameter of first lens 110 from being too large, thereby miniaturizing wide-angle lens 1000. Furthermore, by setting (R11+R12) / (R11-R12) to be less than 1.900, sufficient refractive power of first lens 110 can be ensured, thereby facilitating an increase in the maximum half-field angle ω of first lens 110. Furthermore, sufficient thickness of first lens 110 can be ensured to prevent damage to first lens 110 due to impact, etc.

[0313] Furthermore, in condition 6-5, by further setting (R11+R12) / (R11-R12) to be greater than 1.600, the radius of curvature R12 of the image-side lens surface of the first lens 110, i.e., the second surface 2, can be further prevented from being too small, thereby facilitating molding of the second surface 2 of the first lens 110. Furthermore, the radius of curvature R11 of the object-side lens surface of the first lens 110, i.e., the first surface 1, can be further prevented from being too large, thereby further preventing the diameter of the first lens 110 from being too large, thereby further miniaturizing the wide-angle lens 1000. Furthermore, by further setting (R11+R12) / (R11-R12) to be less than 1.850, sufficient refractive power of the first lens 110 can be further ensured, thereby facilitating increasing the maximum half-angle of view ω of the first lens 110. Furthermore, sufficient thickness of the first lens 110 can be further ensured, further preventing damage to the first lens 110 due to impact, etc.

[0314] Furthermore, as can be seen from Table 11, the thickness T1 of the first lens 110 is 1.700 mm (the thickness T1 of the first lens 110 is defined as the distance between the object-side lens surface, i.e., the first surface 1, and the image-side lens surface, i.e., the second surface 2, of the first lens 110 in the optical axis direction), and the sag height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 110 is 1.803 mm. Therefore, the following condition 6-6 is satisfied:

[0315] 0.700<T1 / Sag12<1.100.

[0316] Under condition 6-6, by setting the ratio of the thickness T1 of the first lens 110 to the sagittal height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 110 to be greater than 0.700, it is possible to ensure that the first lens 110 has sufficient thickness to prevent damage to the first lens 110 caused by impact. Furthermore, by setting the ratio of the thickness T1 of the first lens 110 to the sagittal height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 110 to be less than 1.100, it is possible to prevent the first lens 110 from being too thick, thereby preventing the inability to obtain the desired negative focal length. Furthermore, in the wide-angle lens 1000 of this embodiment, the object-image distance d of the wide-angle lens 1000 is 13.383 mm, and the focal length f of the wide-angle lens 1000 as a whole is 1.018 mm. Therefore, the following condition 6-7 is satisfied:

[0317] 11.000<d / f<15.000.

[0318] In conditions 6-7, by setting the ratio of the object-image distance d of the wide-angle lens 1000 to the focal length f of the entire wide-angle lens 1000 to be greater than 11.000, various aberrations can be easily corrected appropriately, thereby easily obtaining excellent optical characteristics; in addition, by setting the ratio of the object-image distance d of the wide-angle lens 1000 to the focal length f of the entire wide-angle lens 1000 to be less than 15.000, the wide-angle lens 1000 can be prevented from becoming too large while avoiding the entire length of the wide-angle lens 1000 from becoming too long.

[0319] In summary, in this embodiment, by constructing the wide-angle lens 1000 in the above manner, as shown in FIG. Figures 22A to 24L As shown, various aberrations such as curvature of field, chromatic aberration of magnification, and coma can be appropriately corrected, and miniaturization can be achieved while widening the maximum half angle of view ω.

[0320] (Implementation 7)

[0321] Figure 25 1 is an explanatory diagram showing a wide-angle lens according to a seventh embodiment of the present invention. Figure 26A 1 is an explanatory diagram showing field curvature and distortion of a wide-angle lens according to Embodiment 7 of the present invention. Figure 26B 1 is an explanatory diagram showing field curvature and distortion of a wide-angle lens according to Embodiment 7 of the present invention. Figure 27A 1 is an explanatory diagram showing vertical axial chromatic aberration (lateral chromatic aberration) of a wide-angle lens according to Embodiment 7 of the present invention. Figure 27B 1 is an explanatory diagram showing spherical aberration (longitudinal aberration) of a wide-angle lens according to Embodiment 7 of the present invention. Figures 28A to 28L : is an explanatory diagram showing the lateral aberration of the wide-angle lens according to the seventh embodiment of the present invention. Figure 26A 、 Figure 26B 、 Figure 27A 、 Figure 27B 、 Figures 28A to 28L In the figure, the correlation curve of red light R (wavelength of 656nm) is marked with R, the correlation curve of green light G (wavelength of 588nm) is marked with G, and the correlation curve of blue light B (wavelength of 486nm) is marked with B. T is used to indicate correlation with the meridian plane, and S is used to indicate correlation with the sagittal plane. In addition, Figures 28A to 28L In the example, the maximum scale of the vertical axis is ±50.000 μm.

[0322] like Figure 25 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, which are arranged in sequence from the object side (L1 side), wherein the sixth lens 160 and the seventh lens 170 are bonded together by an adhesive to form a cemented lens.

[0323] Here, since the basic structure of the wide-angle lens 1000 in this embodiment (i.e., the first lens 110 (i.e., the first lens 110 is arranged at the position closest to the object side), the second lens 120 (i.e., the second lens 120 is arranged adjacent to the image side of the first lens 110), whether 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 optical 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 the wide-angle lens in Embodiment 1, it will not be elaborated on in detail here.

[0324] In addition, if Figure 25 As shown, similar to the first embodiment, a light shielding sheet 190 is provided between the second lens 120 and the fourth lens 130 , a filter 200 is arranged on the image side of the seventh lens 170 , and an imaging element 300 is arranged on the image side of the filter 200 .

[0325] In this embodiment, the focal length f (Effective Focal Length) of the entire lens system is 1.019 mm, the object-image distance d (Total Track) is 13.381 mm, the F value (Image Space F / #) is 2.0163, the maximum half field of view (Max. Field of Angle) is 108 degrees, and the entrance pupil diameter HEP is 0.505 mm.

[0326] Table 13 shows the physical properties of each surface of the wide-angle lens 1000 according to this embodiment, and Tables 14-1 and 14-2 show the aspheric coefficient of each surface of the wide-angle lens 1000 according to this embodiment.

[0327] (Table 13)

[0328]

[0329] In Table 11 above, the units of the radius of curvature, thickness, focal length, effective radius, and sagittal height are mm, Nd is the refractive index for light of 587.56 nm, νd is the Abbe number, and * indicates an aspherical surface.

[0330] (Table 14-1)

[0331] noodle c(1 / radius of curvature) K A4 A6 3 1.09439E-01 0.00000E+00 -4.39546E-03 2.94241E-03 4 8.39842E-01 -3.71100E+00 2.15910E-01 -7.58275E-02 5 -8.48248E-02 0.00000E+00 -5.99821E-03 9.40179E-03 6 -2.61938E-01 0.00000E+00 1.43606E-02 2.26240E-02 7 -4.49438E-02 0.00000E+00 1.40010E-02 4.01310E-02 8 -3.68664E-01 0.00000E+00 1.66786E-02 2.21644E-02 12 -2.77778E-01 0.00000E+00 -2.23667E-02 7.48072E-03 13 1.03842E+00 -1.00000E+00 4.72309E-02 -6.05266E-02 14 -4.67071E-01 0.00000E+00 5.76337E-02 -4.72421E-02

[0332] (Table 14-2)

[0333] noodle 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

[0334] In Tables 14-1 and 14-2 above, when the lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, the curvature radius is set to a positive value, and when the lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side, the curvature radius is set to a negative value.

[0335] In addition, in the above Table 14-1 and Table 14-2, the aspherical coefficients A4, A6, A8, A10, A12, A14, and A16 when the aspherical shape of each surface is represented by the above Mathematical Formula 1 are shown.

[0336] Here, as described above, the maximum half-field angle ω of the wide-angle lens 1000 as a whole is 108 degrees, which satisfies the following condition 7-1:

[0337] 98°<ω<120°.

[0338] In condition 7-1, by setting the maximum half field angle ω to be greater than 98°, the maximum half field angle ω can be expanded. In addition, by setting the maximum half field angle ω to be less than 120°, it is possible to prevent the peripheral part of the image from being darkened due to the light intensity ratio at the periphery of the lens 1000 being less than the light intensity ratio at the center, thereby expanding the maximum half field angle ω of the wide-angle lens 1000 while achieving the miniaturization of the entire wide-angle lens 1000.

[0339] Furthermore, the focal length f of the wide-angle lens 1000 as a whole is 1.019 mm, and the entrance pupil diameter HEP is 0.505 mm. Therefore, the following condition 7-2 is satisfied:

[0340] f / HEP<2.3.

[0341] In condition 7-2, by setting the ratio of the focal length f of the entire wide-angle lens 1000 to the entrance pupil diameter HEP to f / HEP<2.3, the brightness of the wide-angle lens 1000 can be ensured and the wide-angle lens 1000 can be used in a high-pixel imaging element.

[0342] Furthermore, as shown in Table 13, the effective radius sd12 of the image-side lens surface of the first lens 110, i.e., the second surface 2, is 2.800 mm, and the curvature radius R12 of the second surface 2 of the first lens 110 is 2.910 mm. Therefore, the following condition 7-3 is satisfied:

[0343] 0.890<sd12 / R12<0.970.

[0344] In condition 7-3, by setting the ratio of the effective radius sd12 of the second surface 2 of the first lens 110 to the radius of curvature R12 to be greater than 0.890, the half angle of view can be increased, and in particular, the half angle of view can be increased to 98° or greater. In addition, by setting the ratio of the effective radius sd12 of the second surface 2 of the first lens 110 to the radius of curvature R12 to be less than 0.970, the angle between the peripheral portion of the second surface 2 of the first lens 110 made of glass and the tangent line can be suppressed from being too small, thereby preventing the second surface 2 of the first lens 110 from being unable to be polished.

[0345] Furthermore, as can be seen from Table 13, the radius of curvature R11 of the object-side lens surface of the first lens 110, i.e., the first surface 1, is 12.500 mm, and the radius of curvature R12 of the image-side lens surface of the first lens 110, i.e., the second surface 2, is 2.910 mm. Therefore, the following condition 7-4 is satisfied:

[0346] 1.300<(R11+R12) / (R11-R12)<1.900,

[0347] And also meet the following conditions 7-5:

[0348] 1.600<(R11+R12) / (R11-R12)<1.850.

[0349] In condition 7-4, by setting (R11+R12) / (R11-R12) to be greater than 1.300, the radius of curvature R12 of the image-side lens surface of first lens 110, i.e., second surface 2, can be prevented from being too small, thereby facilitating molding of second surface 2 of first lens 110. Furthermore, the radius of curvature R11 of the object-side lens surface of first lens 110, i.e., first surface 1, can be prevented from being too large, thereby preventing the diameter of first lens 110 from being too large, thereby miniaturizing wide-angle lens 1000. Furthermore, by setting (R11+R12) / (R11-R12) to be less than 1.900, sufficient refractive power of first lens 110 can be ensured, thereby facilitating an increase in the maximum half-field angle ω of first lens 110. Furthermore, sufficient thickness of first lens 110 can be ensured to prevent damage to first lens 110 due to impact, etc.

[0350] Furthermore, in condition 7-5, by further setting (R11+R12) / (R11-R12) to be greater than 1.600, the radius of curvature R12 of the image-side lens surface of the first lens 110, i.e., the second surface 2, can be further prevented from being too small, thereby facilitating molding of the second surface 2 of the first lens 110. Furthermore, the radius of curvature R11 of the object-side lens surface of the first lens 110, i.e., the first surface 1, can be further prevented from being too large, thereby further preventing the diameter of the first lens 110 from being too large, thereby further miniaturizing the wide-angle lens 1000. Furthermore, by further setting (R11+R12) / (R11-R12) to be less than 1.850, sufficient refractive power of the first lens 110 can be further ensured, thereby facilitating increasing the maximum half-angle of view ω of the first lens 110. Furthermore, sufficient thickness of the first lens 110 can be further ensured, further preventing damage to the first lens 110 due to impact, etc.

[0351] Furthermore, as can be seen from Table 13, the thickness T1 of the first lens 110 is 1.700 mm (the thickness T1 of the first lens 110 is defined as the distance between the object-side lens surface, i.e., the first surface 1, and the image-side lens surface, i.e., the second surface 2, of the first lens 110 in the optical axis direction), and the sag height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 11 is 2.117 mm. Therefore, the following conditions 7-6 are satisfied:

[0352] 0.700<T1 / Sag12<1.100.

[0353] Under condition 7-6, by setting the ratio of the thickness T1 of the first lens 110 to the sagittal height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 110 to be greater than 0.700, it is possible to ensure that the first lens 110 has sufficient thickness to prevent the first lens 110 from being damaged by impact. In addition, by setting the ratio of the thickness T1 of the first lens 110 to the sagittal height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 110 to be less than 1.100, it is possible to prevent the first lens 110 from being too thick, thereby preventing the ideal negative optical focal length from being obtained.

[0354] Furthermore, in the wide-angle lens 1000 of this embodiment, the object-image distance d of the wide-angle lens 1000 is 13.381 mm, and the focal length f of the entire wide-angle lens 1000 is 1.019 mm. Therefore, the following condition 7-7 is satisfied:

[0355] 11.000<d / f<15.000.

[0356] In condition 7-7, by setting the ratio of the object-image distance d of the wide-angle lens 1000 to the focal length f of the entire wide-angle lens 1000 to be greater than 11.000, various aberrations can be easily corrected appropriately, thereby easily obtaining excellent optical characteristics; in addition, by setting the ratio of the object-image distance d of the wide-angle lens 1000 to the focal length f of the entire wide-angle lens 1000 to be less than 15.000, the wide-angle lens 1000 can be prevented from becoming too large while avoiding the overall length of the wide-angle lens 1000 from becoming too long.

[0357] In summary, in this embodiment, by constructing the wide-angle lens 1000 in the above manner, as shown in FIG. Figures 26A to 28L As shown, various aberrations such as curvature of field, chromatic aberration of magnification, and coma can be appropriately corrected, and miniaturization can be achieved while widening the maximum half angle of view ω.

[0358] (Implementation 8)

[0359] Figure 29 1 is an explanatory diagram showing a wide-angle lens according to an eighth embodiment of the present invention. Figure 30A 1 is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to the eighth embodiment of the present invention. Figure 30B 1 is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to the eighth embodiment of the present invention. Figure 31A 1 is an explanatory diagram showing vertical axial chromatic aberration (lateral chromatic aberration) of a wide-angle lens according to Embodiment 8 of the present invention. Figure 31B 1 is an explanatory diagram showing spherical aberration (longitudinal aberration) of the wide-angle lens according to the eighth embodiment of the present invention. Figures 32A to 32L : is an explanatory diagram showing the lateral aberration of the wide-angle lens according to the eighth embodiment of the present invention. Figure 30A 、 Figure 30B 、 Figure 31A 、 Figure 31B 、 Figures 32A to 32L In the figure, the correlation curve of red light R (wavelength of 656nm) is marked with R, the correlation curve of green light G (wavelength of 588nm) is marked with G, and the correlation curve of blue light B (wavelength of 486nm) is marked with B. T is used to indicate correlation with the meridian plane, and S is used to indicate correlation with the sagittal plane. In addition, Figures 32A to 32L In the example, the maximum scale of the vertical axis is ±50.000 μm.

[0360] like Figure 29As shown, the wide-angle lens 1000 includes, arranged in order from the object side (L1 side), a first lens 110 (i.e., the first lens 110 is arranged at the position closest to the object side), a second lens 120 (i.e., the second lens 120 is arranged adjacent to the image side of the first lens 110), 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 cemented lens.

[0361] 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 optical power, whether they are glass lenses or plastic lenses, and whether the object-side and image-side surfaces 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 elaborated on here.

[0362] In addition, if Figure 29 As shown, similar to the first embodiment, a light shielding sheet 190 is provided between the second lens 120 and the fourth lens 130 , a filter 200 is arranged on the image side of the seventh lens 170 , and an imaging element 300 is arranged on the image side of the filter 200 .

[0363] In this embodiment, the focal length f (Effective Focal Length) of the entire lens system is 1.019 mm, the object-image distance d (Total Track) is 13.397 mm, the F value (Image Space F / #) is 2.012, the maximum half field of view (Max. Field of Angle) is 108.004 degrees, and the entrance pupil diameter HEP is 0.506 mm.

[0364] Table 15 shows the physical properties of each surface of the wide-angle lens 1000 according to this embodiment, and Tables 16-1 and 16-2 show the aspheric coefficient of each surface of the wide-angle lens 1000 according to this embodiment.

[0365] (Table 15)

[0366]

[0367] In Table 15 above, the units of the radius of curvature, thickness, focal length, effective radius, and sagittal height are mm, Nd is the refractive index for light of 587.56 nm, νd is the Abbe number, and * indicates an aspherical surface.

[0368] (Table 16-1)

[0369] noodle c(1 / radius of curvature) K A4 A6 3 1.29990E-01 0.00000E+00 1.79733E-03 -1.14149E-03 4 8.08669E-01 -4.00000E+00 2.15100E-01 -8.02378E-02 5 -1.51355E-01 0.00000E+00 -1.09624E-02 -8.73052E-03 6 -2.85185E-01 0.00000E+00 4.64269E-03 4.90763E-03 7 -7.91052E-02 0.00000E+00 1.02155E-02 7.50888E-03 8 -3.09828E-01 0.00000E+00 7.49234E-03 1.54584E-03 12 -2.58792E-01 0.00000E+00 -3.14257E-02 2.35226E-03 13 1.02041E+00 -1.00000E+00 3.07479E-02 -4.89661E-02 14 -4.64857E-01 0.00000E+00 4.79842E-02 -2.97957E-02

[0370] (Table 16-2)

[0371] noodle 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

[0372] In Tables 16-1 and 16-2 above, when the lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, the curvature radius is set to a positive value, and when the lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side, the curvature radius is set to a negative value.

[0373] In addition, in the above Table 16-1 and Table 16-2, the aspherical coefficients A4, A6, A8, A10, A12, A14, and A16 when the aspherical shape of each surface is represented by the above Mathematical Formula 1 are shown.

[0374] Here, as described above, the maximum half-field angle ω of the wide-angle lens 1000 as a whole is 108.004 degrees, which satisfies the following condition 8-1:

[0375] 98°<ω<120°.

[0376] In condition 8-1, by setting the maximum half field angle ω to be greater than 98°, the maximum half field angle ω can be expanded. In addition, by setting the maximum half field angle ω to be less than 120°, it is possible to prevent the peripheral portion of the image from becoming darker due to the light intensity ratio at the periphery of the lens 1000 being less than the light intensity ratio at the center, thereby expanding the maximum half field angle ω of the wide-angle lens 1000 while achieving miniaturization of the entire wide-angle lens 1000.

[0377] Furthermore, the focal length f of the wide-angle lens 1000 as a whole is 1.019 mm, and the entrance pupil diameter HEP is 0.506 mm. Therefore, the following condition 8-2 is satisfied:

[0378] f / HEP<2.3.

[0379] In condition 8-2, by setting the ratio of the focal length f of the entire wide-angle lens 1000 to the entrance pupil diameter HEP to f / HEP<2.3, the brightness of the wide-angle lens 1000 can be ensured and the wide-angle lens 1000 can be used in a high-pixel imaging element.

[0380] Furthermore, as can be seen from Table 15, the effective radius sd12 of the image-side lens surface of the first lens 110, i.e., the second surface 2, is 2.731 mm, and the radius of curvature R12 of the second surface 2 of the first lens 110 is 2.910 mm. Therefore, the following condition 8-3 is satisfied:

[0381] 0.890<sd12 / R12<0.970.

[0382] In condition 8-3, by setting the ratio of the effective radius sd12 of the second surface 2 of the first lens 110 to the radius of curvature R12 to be greater than 0.890, the half angle of view can be increased, and in particular, the half angle of view can be increased to 98° or greater. In addition, by setting the ratio of the effective radius sd12 of the second surface 2 of the first lens 110 to the radius of curvature R12 to be less than 0.970, the angle between the peripheral portion of the second surface 2 of the first lens 110 made of glass and the tangent line can be suppressed from being too small, thereby preventing the second surface 2 of the first lens 110 from being unable to be polished.

[0383] Furthermore, as can be seen from Table 15, the radius of curvature R11 of the object-side lens surface of the first lens 110, i.e., the first surface 1, is 12.100 mm, and the radius of curvature R12 of the image-side lens surface of the first lens 110, i.e., the second surface 2, is 2.910 mm. Therefore, the following condition 8-4 is satisfied:

[0384] 1.300<(R11+R12) / (R11-R12)<1.900,

[0385] And also meet the following conditions 8-5:

[0386] 1.600<(R11+R12) / (R11-R12)<1.850.

[0387] In condition 8-4, by setting (R11+R12) / (R11-R12) to be greater than 1.300, the radius of curvature R12 of the image-side lens surface of first lens 110, i.e., second surface 2, can be prevented from being too small, thereby facilitating molding of second surface 2 of first lens 110. Furthermore, the radius of curvature R11 of the object-side lens surface of first lens 110, i.e., first surface 1, can be prevented from being too large, thereby preventing the diameter of first lens 110 from being too large, thereby miniaturizing wide-angle lens 1000. Furthermore, by setting (R11+R12) / (R11-R12) to be less than 1.900, sufficient refractive power of first lens 110 can be ensured, thereby facilitating an increase in the maximum half-angle of view ω of first lens 110. Furthermore, sufficient thickness of first lens 110 can be ensured to prevent damage to first lens 110 due to impact, etc.

[0388] Furthermore, in condition 8-5, by further setting (R11+R12) / (R11-R12) to be greater than 1.600, the radius of curvature R12 of the image-side lens surface of the first lens 110, i.e., the second surface 2, can be further prevented from being too small, thereby facilitating molding of the second surface 2 of the first lens 110. Furthermore, the radius of curvature R11 of the object-side lens surface of the first lens 110, i.e., the first surface 1, can be further prevented from being too large, thereby further preventing the diameter of the first lens 110 from being too large, thereby further miniaturizing the wide-angle lens 1000. Furthermore, by further setting (R11+R12) / (R11-R12) to be less than 1.850, sufficient refractive power of the first lens 110 can be further ensured, thereby facilitating increasing the maximum half-angle of view ω of the first lens 110. Furthermore, sufficient thickness of the first lens 110 can be further ensured, further preventing damage to the first lens 110 due to impact, etc.

[0389] Furthermore, as can be seen from Table 15, the thickness T1 of the first lens 110 is 1.730 mm (the thickness T1 of the first lens 110 is defined as the distance between the object-side lens surface, i.e., the first surface 1, and the image-side lens surface, i.e., the second surface 2, of the first lens 110 in the optical axis direction), and the sag height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 11 is 1.905 mm. Therefore, the following conditions 8-6 are satisfied:

[0390] 0.700<T1 / Sag12<1.100.

[0391] Under condition 8-6, by setting the ratio of the thickness T1 of the first lens 110 to the sagittal height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 110 to be greater than 0.700, it is possible to ensure that the first lens 110 has sufficient thickness to prevent the first lens 110 from being damaged by impact. In addition, by setting the ratio of the thickness T1 of the first lens 110 to the sagittal height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 110 to be less than 1.100, it is possible to prevent the first lens 110 from being too thick, thereby preventing the ideal negative optical focal length from being obtained.

[0392] Furthermore, in the wide-angle lens 1000 of this embodiment, the object-image distance d of the wide-angle lens 1000 is 13.397 mm, and the focal length f of the entire wide-angle lens 1000 is 1.019 mm. Therefore, the following conditions 8-7 are satisfied:

[0393] 11.000<d / f<15.000.

[0394] In condition 8-7, by setting the ratio of the object-image distance d of the wide-angle lens 1000 to the focal length f of the entire wide-angle lens 1000 to be greater than 11.000, various aberrations can be appropriately corrected, thereby easily obtaining excellent optical characteristics; in addition, by setting the ratio of the object-image distance d of the wide-angle lens 1000 to the focal length f of the entire wide-angle lens 1000 to be less than 15.000, the wide-angle lens 1000 can be prevented from becoming too large while avoiding the overall length of the wide-angle lens 1000 from becoming too long.

[0395] In summary, in this embodiment, by constructing the wide-angle lens 1000 in the above manner, as shown in FIG. Figures 30A to 32L As shown, various aberrations such as curvature of field, chromatic aberration of magnification, and coma can be appropriately corrected, and miniaturization can be achieved while widening the maximum half angle of view ω.

[0396] (Implementation 9)

[0397] Figure 33 1 is an explanatory diagram showing a wide-angle lens according to Embodiment 9 of the present invention. Figure 34A 1 is an explanatory diagram showing field curvature and distortion of a wide-angle lens according to Embodiment 9 of the present invention. Figure 34B 1 is an explanatory diagram showing field curvature and distortion of a wide-angle lens according to Embodiment 9 of the present invention. Figure 35A 1 is an explanatory diagram showing vertical axial chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to Embodiment 9 of the present invention. Figure 35B 1 is an explanatory diagram showing spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 9 of the present invention. Figures 36A to 36L : is an explanatory diagram showing the lateral aberration of the wide-angle lens according to the ninth embodiment of the present invention. Figure 34A 、 Figure 34B 、 Figure 35A 、 Figure 35B 、 Figures 36A to 36L In the figure, the correlation curve of red light R (wavelength of 656nm) is marked with R, the correlation curve of green light G (wavelength of 588nm) is marked with G, and the correlation curve of blue light B (wavelength of 486nm) is marked with B. T is used to indicate correlation with the meridian plane, and S is used to indicate correlation with the sagittal plane. In addition, Figures 36A to 36L In the example, the maximum scale of the vertical axis is ±50.000 μm.

[0398] like Figure 33As shown, the wide-angle lens 1000 includes, arranged in order from the object side (L1 side), a first lens 110 (i.e., the first lens 110 is arranged at the position closest to the object side), a second lens 120 (i.e., the second lens 120 is arranged adjacent to the image side of the first lens 110), 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 cemented lens.

[0399] 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 optical power, whether they are glass lenses or plastic lenses, and whether the object-side and image-side surfaces 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 elaborated on here.

[0400] In addition, if Figure 33 As shown, similar to the first embodiment, a light shielding sheet 190 is provided between the second lens 120 and the fourth lens 130 , a filter 200 is arranged on the image side of the seventh lens 170 , and an imaging element 300 is arranged on the image side of the filter 200 .

[0401] In this embodiment, the focal length 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 of view (Max. Field of Angle) is 106 degrees, and the entrance pupil diameter HEP is 0.515 mm.

[0402] Table 17 shows the physical properties of each surface of the wide-angle lens 1000 according to this embodiment, and Tables 18-1 and 18-2 show the aspheric coefficient of each surface of the wide-angle lens 1000 according to this embodiment.

[0403] (Table 17)

[0404]

[0405] In Table 17 above, the units of the radius of curvature, thickness, focal length, effective radius, and sagittal height are mm, Nd is the refractive index for light of 587.56 nm, νd is the Abbe number, and * indicates an aspherical surface.

[0406] (Table 18-1)

[0407] noodle c(1 / radius of curvature) 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

[0408] (Table 18-2)

[0409] noodle 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

[0410] In Tables 18-1 and 18-2 above, when the lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, the curvature radius is set to a positive value, and when the lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side, the curvature radius is set to a negative value.

[0411] In addition, in the above Table 18-1 and Table 18-2, the aspherical coefficients A4, A6, A8, A10, A12, A14, and A16 when the aspherical shape of each surface is represented by the above mathematical formula 1 are shown.

[0412] Here, as described above, the maximum half-field angle ω of the wide-angle lens 1000 as a whole is 106 degrees, which satisfies the following condition 9-1:

[0413] 98°<ω<120°.

[0414] In condition 9-1, by setting the maximum half field angle ω to be greater than 98°, the maximum half field angle ω can be expanded. In addition, by setting the maximum half field angle ω to be less than 120°, it is possible to prevent the peripheral portion of the image from becoming darker due to the light intensity ratio at the periphery of the lens 1000 being less than the light intensity ratio at the center, thereby expanding the maximum half field angle ω of the wide-angle lens 1000 while achieving miniaturization of the entire wide-angle lens 1000.

[0415] Furthermore, the focal length f of the wide-angle lens 1000 as a whole is 1.030 mm, and the entrance pupil diameter HEP is 0.515 mm. Therefore, the following condition 9-2 is satisfied:

[0416] f / HEP<2.3.

[0417] In condition 9-2, by setting the ratio of the focal length f of the entire wide-angle lens 1000 to the entrance pupil diameter HEP to f / HEP<2.3, the brightness of the wide-angle lens 1000 can be ensured and the wide-angle lens 1000 can be used in a high-pixel imaging element.

[0418] Furthermore, as can be seen from Table 17, the effective radius sd12 of the image-side lens surface of the first lens 110, i.e., the second surface 2, is 2.907 mm, and the radius of curvature R12 of the second surface 2 of the first lens 110 is 3.168 mm. Therefore, the following condition 9-3 is satisfied:

[0419] 0.890<sd12 / R12<0.970.

[0420] In condition 9-3, by setting the ratio of the effective radius sd12 of the second surface 2 of the first lens 110 to the radius of curvature R12 to be greater than 0.890, the half angle of view can be increased, and in particular, the half angle of view can be increased to 98° or greater. In addition, by setting the ratio of the effective radius sd12 of the second surface 2 of the first lens 110 to the radius of curvature R12 to be less than 0.970, the angle between the peripheral portion of the second surface 2 of the first lens 110 made of glass and the tangent line can be suppressed from being too small, thereby preventing the second surface 2 of the first lens 110 from being unable to be polished.

[0421] Furthermore, as can be seen from Table 17, the radius of curvature R11 of the object-side lens surface of the first lens 110, i.e., the first surface 1, is 12.641 mm, and the radius of curvature R12 of the image-side lens surface of the first lens 110, i.e., the second surface 2, is 3.168 mm. Therefore, the following condition 9-4 is satisfied:

[0422] 1.300<(R11+R12) / (R11-R12)<1.900,

[0423] And also meet the following conditions 9-5:

[0424] 1.600<(R11+R12) / (R11-R12)<1.850.

[0425] In condition 9-4, by setting (R11+R12) / (R11-R12) to be greater than 1.300, the radius of curvature R12 of the image-side lens surface of first lens 110, i.e., second surface 2, can be prevented from being too small, thereby facilitating molding of second surface 2 of first lens 110. Furthermore, the radius of curvature R11 of the object-side lens surface of first lens 110, i.e., first surface 1, can be prevented from being too large, thereby preventing the diameter of first lens 110 from being too large, thereby miniaturizing wide-angle lens 1000. Furthermore, by setting (R11+R12) / (R11-R12) to be less than 1.900, sufficient refractive power of first lens 110 can be ensured, thereby facilitating an increase in the maximum half-field angle ω of first lens 110. Furthermore, sufficient thickness of first lens 110 can be ensured to prevent damage to first lens 110 due to impact, etc.

[0426] Furthermore, in condition 9-5, by further setting (R11+R12) / (R11-R12) to be greater than 1.600, the radius of curvature R12 of the image-side lens surface of the first lens 110, i.e., the second surface 2, can be further prevented from being too small, thereby facilitating molding of the second surface 2 of the first lens 110. Furthermore, the radius of curvature R11 of the object-side lens surface of the first lens 110, i.e., the first surface 1, can be further prevented from being too large, thereby further preventing the diameter of the first lens 110 from being too large, thereby further miniaturizing the wide-angle lens 1000. Furthermore, by further setting (R11+R12) / (R11-R12) to be less than 1.850, sufficient refractive power of the first lens 110 can be further ensured, thereby facilitating increasing the maximum half-angle of view ω of the first lens 110. Furthermore, sufficient thickness of the first lens 110 can be further ensured, further preventing damage to the first lens 110 due to impact, etc.

[0427] Furthermore, as can be seen from Table 17, the thickness T1 of the first lens 110 is 1.659 mm (the thickness T1 of the first lens 110 is defined as the distance between the object-side lens surface, i.e., the first surface 1, and the image-side lens surface, i.e., the second surface 2, of the first lens 110 in the optical axis direction), and the sag height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 11 is 1.908 mm. Therefore, the following conditions 9-6 are satisfied:

[0428] 0.700<T1 / Sag12<1.100.

[0429] Under condition 9-6, by setting the ratio of the thickness T1 of the first lens 110 to the sagittal height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 110 to be greater than 0.700, it is possible to ensure that the first lens 110 has sufficient thickness to prevent the first lens 110 from being damaged by impact. In addition, by setting the ratio of the thickness T1 of the first lens 110 to the sagittal height Sag12 of the image-side lens surface, i.e., the second surface 2, of the first lens 110 to be less than 1.100, it is possible to prevent the first lens 110 from being too thick, thereby preventing the ideal negative optical focal length from being obtained.

[0430] Furthermore, in the wide-angle lens 1000 of this embodiment, the object-image distance d of the wide-angle lens 1000 is 13.609 mm, and the focal length f of the entire wide-angle lens 1000 is 1.030 mm. Therefore, the following condition 9-7 is satisfied:

[0431] 11.000<d / f<15.000.

[0432] In condition 9-7, by setting the ratio of the object-image distance d of the wide-angle lens 1000 to the focal length f of the entire wide-angle lens 1000 to be greater than 11.000, various aberrations can be easily corrected appropriately, thereby easily obtaining excellent optical characteristics; in addition, by setting the ratio of the object-image distance d of the wide-angle lens 1000 to the focal length f of the entire wide-angle lens 1000 to be less than 15.000, the wide-angle lens 1000 can be prevented from becoming too large while avoiding the overall length of the wide-angle lens 1000 from becoming too long.

[0433] In summary, in this embodiment, by constructing the wide-angle lens 1000 in the above manner, as shown in FIG. Figures 34A to 36L As shown, various aberrations such as curvature of field, chromatic aberration of magnification, and coma can be appropriately corrected, and miniaturization can be achieved while widening the maximum half angle of view ω.

[0434] The present invention is described above by way of example with reference to the accompanying drawings. It is apparent that the specific implementation of the present invention is not limited to the above-mentioned embodiments.

[0435] For example, in the above embodiment, 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.

[0436] Furthermore, in the above embodiment, the first lens 110 and the fifth lens 150 may be formed of plastic lenses, and the second lens 120 , the third lens 130 , the fourth lens 140 , the sixth lens 160 and the seventh lens 170 may be formed of glass lenses.

[0437] In the above embodiment, the wide-angle lens 1000 is described as having seven lenses as a lens group. However, the number of lenses in the wide-angle lens 1000 is not limited to seven, and may be six or less or eight or more according to actual needs.

Claims

1. A wide-angle lens, characterized in that: The wide-angle lens includes a lens group and an aperture, wherein the lens group includes seven lenses, and the seven lenses and the aperture are arranged in the order of a first lens, a second lens, a third lens, a fourth lens, the aperture, a fifth lens, a sixth lens, and a seventh lens from the object side. The first lens is a negative lens, The second lens is a negative lens, The third lens is a positive lens, The fourth lens is a positive lens, The fifth lens is a positive lens, The sixth lens is a negative lens, The seventh lens is a positive lens, When the maximum half-angle of view of the wide-angle lens as a whole is denoted as ω, the following relationship is satisfied: 98°<ω<120°, When the focal length of the entire wide-angle lens is defined as f and the entrance pupil diameter of the entire wide-angle lens is defined as HEP, the following relationship is satisfied: f / HEP<2.3, The lens group includes a first lens, which is arranged at a position closest to the object side and is a negative lens with a concave surface facing the image side. When the effective radius of the image-side lens surface of the first lens is sd12 and the curvature radius of the image-side lens surface of the first lens is R12, the following relationship is satisfied: 0.890<sd12 / R12<0.970, When the thickness of the first lens is set to T1 and the sag height of the image-side lens surface of the first lens is set to Sag12, the following relationship is satisfied: 0.700<T1 / Sag12<1.

100.

2. The wide-angle lens according to claim 1, wherein When the curvature radius of the object-side lens surface of the first lens is set to R11 and the curvature radius of the image-side lens surface of the first lens is set to R12, the following relationship is satisfied: 1.300<(R11+R12) / (R11-R12)<1.

900.

3. The wide-angle lens according to claim 2, wherein: 1.600<(R11+R12) / (R11-R12)<1.

850.

4. The wide-angle lens according to any one of claims 1 to 3, wherein: 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. The seventh lens is a positive lens with a convex surface facing the object side and a convex surface facing the image side. The sixth lens and the seventh lens constitute a cemented lens.

5. The wide-angle lens according to claim 4, wherein: The first lens and the fifth lens are glass lenses respectively. The second lens, the third lens, the fourth lens, the sixth lens, and the seventh lens are plastic lenses, respectively.

Images