Wide-angle lens

Abstract

A wide-angle lens, comprising a lens group and an aperture, wherein a plurality of lenses in the lens group are arranged sequentially from the object side in a manner that sandwiches the aperture, the lens group comprising: a first lens, the first lens being positioned closest to the object side and being a negative lens; and a second lens, the second lens being positioned adjacent to the first lens on the image side, the second lens being a negative lens with its concave surface facing the image side as an aspherical surface, wherein when the sag of the image-side lens surface of the second lens is set to Sag22 and the effective radius of the image-side lens surface of the second lens is set to sd22, the following relationship is satisfied: 0.720 < |Sag22 / sd22| < 0.900.

Description

Technical Field

[0001] This invention relates to a wide-angle lens. Background Technology

[0002] As a lens mounted on a vehicle camera, there is a conventional wide-angle lens that includes a first lens, a second lens, a third lens, a fourth lens, an aperture, a fifth lens, a sixth lens, and a seventh lens arranged sequentially from the object side, wherein the sixth lens and the seventh lens constitute a combined lens (see, for example, Patent Document 1).

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

[0004] In practice, it is sometimes necessary to miniaturize automotive cameras equipped with the aforementioned wide-angle lenses. In such cases, miniaturization of the wide-angle lens is required. However, miniaturization of the wide-angle lens can easily lead to the inability to ensure the lens's negative optical power, making it difficult to correct various aberrations. Furthermore, the miniaturization of wide-angle lenses also presents the problem of increased costs due to the difficulty in manufacturing the lenses. Summary of the Invention

[0005] The present invention was made in view of the above-mentioned problems, and its purpose is to provide a wide-angle lens that can ensure the negative optical power of the lens, thereby making it easy to correct various aberrations, easy to manufacture, thereby reducing costs, and easy to miniaturize.

[0006] To achieve the above objectives, the present invention provides a wide-angle lens, wherein the wide-angle lens includes a lens group and an aperture, and a plurality of lenses in the lens group are arranged sequentially from the object side in a manner that sandwiches the aperture. The lens group includes: a first lens, which is arranged at the position closest to the object side and is a negative lens; and a second lens, which is arranged adjacent to the image side of the first lens and is a negative lens with its concave surface facing the image side as an aspherical surface. When the sag of the image-side lens surface of the second lens is set to Sag22 and the effective radius of the image-side lens surface of the second lens is set to sd22, the following relationship is satisfied: 0.720 < |Sag22 / sd22| < 0.900.

[0007] According to the wide-angle lens of the present invention, when the sagitta of the image-side lens surface of the second lens is set to Sag22 and the effective radius of the image-side lens surface of the second lens is set to sd22, the relationship 0.720 < |Sag22 / sd22| < 0.900 is satisfied. Therefore, by setting the absolute value of Sag22 / sd22 to be greater than 0.720, sufficient negative optical power of the second lens can be ensured, thereby facilitating the correction of various aberrations; furthermore, by setting the absolute value of Sag22 / sd22 to be less than 0.900, the excessively small angle between the peripheral portion of the second lens and the tangent can be suppressed, thereby facilitating the manufacture of the second lens, reducing costs, and enabling miniaturization.

[0008] Furthermore, in the wide-angle lens of the present invention, it is preferable that the relationship -1.500 < f12 / f < -1.000 is satisfied when the combined focal distance of the first lens and the second lens is set to f12 and the focal distance of the wide-angle lens as a whole is set to f. More preferably, the relationship -1.500 < f12 / f < -1.200 is satisfied.

[0009] According to the wide-angle lens of the present invention, by setting the ratio of the combined focal distance f12 of the first lens and the second lens to the focal distance f of the wide-angle lens as greater than -1.500, the wide-angle lens can be further ensured to have sufficient negative optical power, thereby expanding the maximum half field of view of the wide-angle lens; in addition, by setting the ratio of the combined focal distance f12 of the first lens and the second lens to the focal distance f of the wide-angle lens as less than -1.000, it is easier to correct various aberrations; by further setting the ratio of the combined focal distance f12 of the first lens and the second lens to the focal distance f of the wide-angle lens as less than -1.200, it is even easier to correct various aberrations.

[0010] Furthermore, in the wide-angle lens of the present invention, it is preferable that when the radius of curvature of the object-side lens surface of the second lens is set to R21 and the radius of curvature of the image-side lens surface of the second lens is set to R22, the relationship 0.890 < (R21 + R22) / (R21 - R22) < 1.500 is satisfied, and more preferably the relationship 1.000 < (R21 + R22) / (R21 - R22) < 1.400 is satisfied.

[0011] According to the wide-angle lens of the present invention, by setting (R21+R22) / (R21-R22) to be greater than 0.890, the optical power of the second lens can be avoided to be too strong, and various aberrations can be easily corrected appropriately, thereby easily obtaining excellent optical characteristics; in addition, by setting (R21+R22) / (R21-R22) to be less than 1.500, it can be ensured that the second lens has sufficient negative optical power, thereby easily expanding the maximum half field of view of the wide-angle lens as a whole.

[0012] Furthermore, by setting (R21+R22) / (R21-R22) to be greater than 1.000, the optical power of the second lens can be further avoided, making it easier to properly correct various aberrations and thus more likely to obtain excellent optical characteristics. In addition, by setting (R21+R22) / (R21-R22) to be less than 1.400, the second lens can be further ensured to have sufficient negative optical power, thus making it easier to expand the maximum half field of view of the wide-angle lens as a whole.

[0013] (Invention Effects)

[0014] According to the present invention, when the sagitta of the image-side lens surface of the second lens is set to Sag22 and the effective radius of the image-side lens surface of the second lens is set to sd22, the relationship 0.720 < |Sag22 / sd22| < 0.900 is satisfied. Therefore, by setting the absolute value of Sag22 / sd22 to be greater than 0.720, sufficient negative optical power of the second lens can be ensured, thereby facilitating the correction of various aberrations. Furthermore, by setting the absolute value of Sag22 / sd22 to be less than 0.900, the excessively small angle between the peripheral portion of the second lens and the tangent can be suppressed, thereby facilitating the manufacture of the second lens, reducing costs, and enabling miniaturization. Attached Figure Description

[0015] Figure 1 This is an explanatory diagram showing the wide-angle lens according to Embodiment 1 of the present invention.

[0016] Figure 2A This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 1 of the present invention.

[0017] Figure 2B This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 1 of the present invention.

[0018] Figure 3A This is an explanatory diagram showing the transverse chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to Embodiment 1 of the present invention.

[0019] Figure 3B This is an explanatory diagram showing the spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 1 of the present invention.

[0020] Figures 4A to 4L This is an explanatory diagram showing the lateral aberration of the wide-angle lens according to Embodiment 1 of the present invention.

[0021] Figure 5 This is an explanatory diagram showing the wide-angle lens according to Embodiment 2 of the present invention.

[0022] Figure 6A This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 2 of the present invention.

[0023] Figure 6B This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 2 of the present invention.

[0024] Figure 7A This is an explanatory diagram showing the transverse chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to Embodiment 2 of the present invention.

[0025] Figure 7B This is an explanatory diagram showing the spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 2 of the present invention.

[0026] Figures 8A to 8L This is an explanatory diagram showing the lateral aberration of the wide-angle lens according to Embodiment 2 of the present invention.

[0027] Figure 9 This is an explanatory diagram showing the wide-angle lens of Embodiment 3 of the present invention.

[0028] Figure 10A This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 3 of the present invention.

[0029] Figure 10B This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 3 of the present invention.

[0030] Figure 11A This is an explanatory diagram showing the transverse chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to Embodiment 3 of the present invention.

[0031] Figure 11B This is an explanatory diagram showing the spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 3 of the present invention.

[0032] Figures 12A to 12L This is an explanatory diagram showing the lateral aberration of the wide-angle lens according to Embodiment 3 of the present invention.

[0033] Figure 13 This is an explanatory diagram showing the wide-angle lens of Embodiment 4 of the present invention.

[0034] Figure 14A This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 4 of the present invention.

[0035] Figure 14B This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 4 of the present invention.

[0036] Figure 15A This is an explanatory diagram showing the transverse chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to Embodiment 4 of the present invention.

[0037] Figure 15BThis is an explanatory diagram showing the spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 4 of the present invention.

[0038] Figures 16A to 16L This is an explanatory diagram showing the lateral aberration of the wide-angle lens according to Embodiment 4 of the present invention.

[0039] Figure 17 This is an explanatory diagram showing the wide-angle lens of Embodiment 5 of the present invention.

[0040] Figure 18A This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 5 of the present invention.

[0041] Figure 18B This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 5 of the present invention.

[0042] Figure 19A This is an explanatory diagram showing the transverse chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to Embodiment 5 of the present invention.

[0043] Figure 19B This is an explanatory diagram showing the spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 5 of the present invention.

[0044] Figures 20A to 20L This is an explanatory diagram showing the lateral aberration of the wide-angle lens according to Embodiment 5 of the present invention.

[0045] Figure 21 This is an explanatory diagram showing the wide-angle lens according to Embodiment 6 of the present invention.

[0046] Figure 22A This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 6 of the present invention.

[0047] Figure 22B This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 6 of the present invention.

[0048] Figure 23A This is an explanatory diagram showing the transverse chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to Embodiment 6 of the present invention.

[0049] Figure 23B This is an explanatory diagram showing the spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 6 of the present invention.

[0050] Figures 24A to 24L This is an explanatory diagram showing the lateral aberration of the wide-angle lens according to Embodiment 6 of the present invention.

[0051] Figure 25 This is an explanatory diagram showing the wide-angle lens of Embodiment 7 of the present invention.

[0052] Figure 26AThis is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 7 of the present invention.

[0053] Figure 26B This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 7 of the present invention.

[0054] Figure 27A This is an explanatory diagram showing the transverse chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to Embodiment 7 of the present invention.

[0055] Figure 27B This is an explanatory diagram showing the spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 7 of the present invention.

[0056] Figures 28A to 28L This is an explanatory diagram showing the lateral aberration of the wide-angle lens according to Embodiment 7 of the present invention.

[0057] Figure 29 This is an explanatory diagram showing the wide-angle lens of Embodiment 8 of the present invention.

[0058] Figure 30A This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 8 of the present invention.

[0059] Figure 30B This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 8 of the present invention.

[0060] Figure 31A This is an explanatory diagram showing the transverse chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to Embodiment 8 of the present invention.

[0061] Figure 31B This is an explanatory diagram showing the spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 8 of the present invention.

[0062] Figures 32A to 32L This is an explanatory diagram showing the lateral aberration of the wide-angle lens according to Embodiment 8 of the present invention.

[0063] (Symbol Explanation)

[0064] 1000 wide-angle lens

[0065] 110 First Lens

[0066] 120 Second Lens

[0067] 130 Third Lens

[0068] 140 Fourth Lens

[0069] 150 Fifth Lens

[0070] 160 Sixth Lens

[0071] 170 Seventh Lens

[0072] 180 aperture

[0073] 190 light-blocking sheet

[0074] 200 filters

[0075] 300 camera elements Detailed Implementation

[0076] Hereinafter, various embodiments of the wide-angle lens of the present invention will be described with reference to the accompanying drawings. Furthermore, in the following description, the object side will be labeled L1 and the image side L2 in the direction of extension of the optical axis L.

[0077] (Implementation Method 1)

[0078] Figure 1 This is an explanatory diagram showing the wide-angle lens according to Embodiment 1 of the present invention. Figure 2A This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 1 of the present invention. Figure 2B This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 1 of the present invention. Figure 3A This is an explanatory diagram showing the transverse chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to Embodiment 1 of the present invention. Figure 3B This is an explanatory diagram showing the spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 1 of the present invention. Figures 4A to 4L This is an explanatory diagram illustrating the lateral aberration of the wide-angle lens according to Embodiment 1 of the present invention. Here, in Figure 2A , Figure 2B , Figure 3A , Figure 3B , Figures 4A to 4L In the diagram, the correlation curve for red light R (wavelength 656nm) is labeled R, the correlation curve for green light G (wavelength 588nm) is labeled G, and the correlation curve for blue light B (wavelength 486nm) is labeled B. T represents correlation with the meridional plane, and S represents correlation with the sagittal plane. Furthermore, in... Figures 4A to 4L In the figure, the maximum scale of the vertical axis is ±50.000 μm.

[0079] like Figure 1 As shown, the wide-angle lens 1000 includes a first lens 110 (i.e., the first lens 110 is positioned closest to the object side), a second lens 120 (i.e., the second lens 120 is positioned 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 arranged sequentially from the object side (L1 side), wherein the sixth lens 160 and the seventh lens 170 are bonded together with an adhesive to form a combined lens.

[0080] Here, the first lens 110 is a lens with negative optical power (referred to as a negative lens) whose convex surface (first surface 1) faces the object side L1 and whose concave surface (second surface 2) faces the image side L2. In this embodiment, the first lens 110 is a glass lens in which the first surface 1 and the second surface 2 are spherical.

[0081] The second lens 120 is a lens with negative optical power, having 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 surfaces for the third surface 3 and the fourth surface 4.

[0082] The third lens 130 is a lens with positive optical power (referred to as a positive lens) whose concave surface (fifth surface 5) faces the object side L1 and whose convex surface (sixth surface 6) faces the image side L2. In this embodiment, the third lens 130 is a plastic lens with aspherical fifth surface 5 and sixth surface 6.

[0083] The fourth lens 140 is a lens with positive optical power, having a concave surface (seventh surface 7) facing the object side L1 and a convex surface (eighth surface 8) facing the image side L2. In this embodiment, the fourth lens 140 is a plastic lens with aspherical surfaces for the seventh surface 7 and the eighth surface 8.

[0084] The fifth lens 150 is a lens with positive optical power, having a convex surface (tenth surface 10) facing the object side L1 and a convex surface (eleventh surface 11) facing the image side L2. In this embodiment, the fifth lens 150 is made of a glass lens.

[0085] The sixth lens 160 is a lens with negative optical power, having a concave surface (twelfth surface 12) facing the object side L1 and a concave surface (thirteenth surface 13) facing the image side L2, and forms a combined lens with the seventh lens 170. In this embodiment, the sixth lens 160 is a plastic lens with aspherical surfaces for the twelfth surface 12 and the thirteenth surface 13.

[0086] The seventh lens 170 is a lens with positive optical power, where the convex surface (thirteenth surface 13) faces the object side L1 and the convex surface (fourteenth surface 14) faces the image side L2. In this embodiment, the seventh lens 170 is a plastic lens where the thirteenth surface 13 and the fourteenth surface 14 are aspherical.

[0087] Furthermore, in this embodiment, such as Figure 1 As shown, a light-shielding plate 190 is provided between the second lens 120 and the fourth lens 130, a filter 200 is provided on the image side of the seventh lens 170, and an image sensor 300 is provided on the image side of the filter 200.

[0088] In this embodiment, the overall focal length f (Effective Focal Length) of the lens system is 1.023 mm, the object-to-image distance d (Total Track) is 13.611 mm, the image space F / # is 2.02, the maximum field of view is 115 degrees, and the entrance pupil diameter HEP is 0.507 mm.

[0089] Table 1 shows the physical properties of each facet of the wide-angle lens 1000 of this embodiment, and Tables 2-1 and 2-2 show the aspherical coefficients of each facet of the wide-angle lens 1000 of this embodiment.

[0090] (Table 1)

[0091]

[0092] In Table 1 above, the units for radius of curvature, thickness, focal distance, effective radius, and sag are mm, Nd is the refractive index of light at 587.56 nanometers, νd is the Abbe number, and * indicates an aspherical surface.

[0093] (Table 2-1)

[0094] 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

[0095] (Table 2-2)

[0096] 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

[0097] In Tables 2-1 and 2-2 above, when the lens surface is a convex surface protruding towards the object side or a concave surface recessed towards the object side, the radius of curvature is set to a positive value; when the lens surface is a convex surface protruding towards the image side or a concave surface recessed towards the image side, the radius of curvature is set to a negative value.

[0098] Furthermore, Tables 2-1 and 2-2 above show the aspherical coefficients A4, A6, A8, A10, A12, A14, and A16 for each aspherical surface shape, expressed by the following formula (Mathematical Formula 1). In the following formula, the sag (the axis in the direction of the optical axis) is set as Z, the height in the direction perpendicular to the optical axis (the height of the ray) is set as r, the conic coefficient is set as K, and the reciprocal of the radius of curvature is set as c.

[0099] [Mathematical Expression 1]

[0100]

[0101] Here, as shown in Table 1, in the wide-angle lens 1000, the sagitta Sag22 of the image-side lens surface (i.e., the fourth surface 4) of the second lens 120 is 1.176 mm, and the effective radius sd22 of the fourth surface 4 of the second lens 120 is 1.461 mm, which satisfies the following condition 1-1:

[0102] 0.720<|Sag22 / sd22|<0.900.

[0103] In condition 1-1, by setting the absolute value of Sag22 / sd22 to be greater than 0.720, it is ensured that the second lens 120 has sufficient negative optical power, thereby making it easy to correct various aberrations. In addition, by setting the absolute value of Sag22 / sd22 to be less than 0.900, it is possible to suppress the angle between the peripheral portion of the second lens 120 and the tangent from being too small, thereby making it easier to manufacture the second lens 120, thereby reducing the overall manufacturing cost of the wide-angle lens 1000 and making it easier to miniaturize the wide-angle lens 1000 as a whole.

[0104] Furthermore, as mentioned above, the overall focal distance f of the wide-angle lens 1000 is 1.023 mm. Table 1 shows that the combined focal distance f12 of the first lens 110 and the second lens 120 is -1.338 mm, thus satisfying the following conditions 1-2:

[0105] -1.500 < f12 / f < -1.000,

[0106] And it also meets the following conditions 1-3:

[0107] -1.500 < f12 / f < -1.200.

[0108] In conditions 1-2, by setting the ratio of the combined focal distance f12 of the first lens 110 and the second lens 120 to the focal distance f of the wide-angle lens 1000 as greater than -1.500, it is possible to further ensure that the wide-angle lens 1000 has sufficient negative optical power, thereby expanding the maximum half field of view of the wide-angle lens 1000; in addition, by setting the ratio of the combined focal distance f12 of the first lens 110 and the second lens 120 to the focal distance f of the wide-angle lens 1000 as less than -1.000, it is easier to correct various aberrations.

[0109] Furthermore, in conditions 1-3, by further setting the ratio of the combined focal distance f12 of the first lens 110 and the second lens 120 to the focal distance f of the wide-angle lens 1000 as a whole to less than -1.200, it becomes even easier to correct various aberrations.

[0110] Furthermore, as shown in Table 1, the radius of curvature R21 of the object-side lens surface (third surface 3) of the second lens 120 is 40.678 mm, and the radius of curvature R22 of the image-side lens surface (fourth surface 4) of the second lens 120 is 1.222 mm, which satisfies the following conditions 1-4:

[0111] 0.890<(R21+R22) / (R21-R22)<1.500,

[0112] And it also meets the following conditions 1-5:

[0113] 1.000<(R21+R22) / (R21-R22)<1.400.

[0114] In conditions 1-4, by setting (R21+R22) / (R21-R22) to be greater than 0.890, the optical power of the second lens 120 can be avoided to be too strong, and various aberrations can be easily corrected appropriately, thereby easily obtaining excellent optical characteristics. In addition, by setting (R21+R22) / (R21-R22) to be less than 1.500, it can be ensured that the second lens 120 has sufficient negative optical power, thereby easily expanding the maximum half field of view of the wide-angle lens 1000 as a whole.

[0115] Furthermore, in conditions 1-5, by further setting (R21+R22) / (R21-R22) to be greater than 1.000, it is possible to further avoid excessive optical power of the second lens 120, and it is easier to properly correct various aberrations, thereby making it easier to obtain excellent optical characteristics. In addition, by further setting (R21+R22) / (R21-R22) to be less than 1.400, it is possible to further ensure that the second lens 120 has sufficient negative optical power, thereby making it easier to expand the maximum half field of view of the wide-angle lens as a whole 1000.

[0116] 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 distance f of the wide-angle lens 1000 as a whole is 1.023 mm. Therefore, the following conditions 1-6 are satisfied:

[0117] 11.000 < d / f < 15.000.

[0118] In conditions 1-6, by setting the ratio of the object-image distance d of the wide-angle lens 1000 to the focal distance f of the wide-angle lens 1000 as 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 distance f of the wide-angle lens 1000 as less than 15.000, the overall length of the wide-angle lens 1000 can be prevented from becoming too long, while suppressing the wide-angle lens 1000 from becoming too large.

[0119] In summary, in this embodiment, by constructing the wide-angle lens 1000 in the manner described above, as follows... Figures 2A to 4L As shown, it can appropriately correct various aberrations such as field curvature, magnification chromatic aberration, and coma aberration, and can ensure the overall negative optical power of the wide-angle lens 1000. This makes it easy to correct various aberrations and easy to manufacture the wide-angle lens 1000, thereby reducing the manufacturing cost of the wide-angle lens 1000 and making it easy to miniaturize the wide-angle lens 1000 as a whole.

[0120] (Implementation Method 2)

[0121] Figure 5 This is an explanatory diagram showing the wide-angle lens according to Embodiment 2 of the present invention. Figure 6A This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 2 of the present invention. Figure 6B This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 2 of the present invention. Figure 7A This is an explanatory diagram showing the transverse chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to Embodiment 2 of the present invention. Figure 7B This is an explanatory diagram showing the spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 2 of the present invention. Figures 8A to 8L This is an explanatory diagram illustrating the lateral aberration of the wide-angle lens according to Embodiment 2 of the present invention. Here, in Figure 6A , Figure 6B , Figure 7A , Figure 7B , Figures 8A to 8L In the diagram, the correlation curve for red light R (wavelength 656nm) is labeled R, the correlation curve for green light G (wavelength 588nm) is labeled G, and the correlation curve for blue light B (wavelength 486nm) is labeled B. T represents correlation with the meridional plane, and S represents correlation with the sagittal plane. Furthermore, in... Figures 8A to 8L In the figure, the maximum scale of the vertical axis is ±50.000 μm.

[0122] like Figure 5 As shown, the wide-angle lens 1000 includes a first lens 110 (i.e., the first lens 110 is positioned closest to the object side), a second lens 120 (i.e., the second lens 120 is positioned 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 arranged sequentially from the object side (L1 side), wherein the sixth lens 160 and the seventh lens 170 are bonded together with an adhesive to form a combined lens.

[0123] 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, whether the object-side surface and the image-side surface are convex or concave, and whether they are spherical or aspherical) is the same as that of the wide-angle lens in Embodiment 1, it will not be elaborated on here.

[0124] In addition, such as Figure 5 As shown, similar to Embodiment 1, a light-shielding sheet 190 is provided between the second lens 120 and the fourth lens 130, a filter 200 is provided on the image side of the seventh lens 170, and an image sensor 300 is provided on the image side of the filter 200.

[0125] In this embodiment, the overall focal length f (Effective Focal Length) of the lens system is 1.062 mm, the object-to-image distance d (Total Track) is 13.610 mm, the image space F / # is 2.02, the maximum field of view is 115 degrees, and the entrance pupil diameter HEP is 0.526 mm.

[0126] Table 3 shows the physical properties of each facet of the wide-angle lens 1000 of this embodiment, and Tables 4-1 and 4-2 show the aspherical coefficients of each facet of the wide-angle lens 1000 of this embodiment.

[0127] (Table 3)

[0128]

[0129] In Table 3 above, the units for radius of curvature, thickness, focal distance, effective radius, and sag are mm, Nd is the refractive index of light at 587.56 nanometers, νd is the Abbe number, and * indicates an aspherical surface.

[0130] (Table 4-1)

[0131] 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

[0132] (Table 4-2)

[0133] 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

[0134] In Tables 4-1 and 4-2 above, when the lens surface is a convex surface protruding towards the object side or a concave surface recessed towards the object side, the radius of curvature is set to a positive value; when the lens surface is a convex surface protruding towards the image side or a concave surface recessed towards the image side, the radius of curvature is set to a negative value.

[0135] Furthermore, Tables 4-1 and 2-2 above show the aspherical coefficients A4, A6, A8, A10, A12, A14, and A16 when each face has an aspherical shape, as represented by the mathematical formula 1 above.

[0136] Here, as shown in Table 3, in the wide-angle lens 1000, the sagitta Sag22 of the image-side lens surface (i.e., the fourth surface 4) of the second lens 120 is 1.106 mm, and the effective radius sd22 of the fourth surface 4 of the second lens 120 is 1.418 mm, which satisfies the following condition 2-1:

[0137] 0.720<|Sag22 / sd22|<0.900.

[0138] In condition 2-1, by setting the absolute value of Sag22 / sd22 to be greater than 0.720, it is ensured that the second lens 120 has sufficient negative optical power, thereby making it easy to correct various aberrations. In addition, by setting the absolute value of Sag22 / sd22 to be less than 0.900, it is possible to suppress the angle between the peripheral portion of the second lens 120 and the tangent from being too small, thereby making it easier to manufacture the second lens 120, thereby reducing the overall manufacturing cost of the wide-angle lens 1000 and making it easier to miniaturize the wide-angle lens 1000 as a whole.

[0139] Furthermore, as mentioned above, the overall focal distance f of the wide-angle lens 1000 is 1.062 mm. Table 3 shows that the combined focal distance f12 of the first lens 110 and the second lens 120 is -1.406 mm, which satisfies the following condition 2-2:

[0140] -1.500 < f12 / f < -1.000,

[0141] And it also meets the following conditions 2-3:

[0142] -1.500 < f12 / f < -1.200.

[0143] In condition 2-2, by setting the ratio of the combined focal distance f12 of the first lens 110 and the second lens 120 to the focal distance f of the wide-angle lens 1000 as greater than -1.500, it is possible to further ensure that the wide-angle lens 1000 has sufficient negative optical power, thereby expanding the maximum half field of view of the wide-angle lens 1000; in addition, by setting the ratio of the combined focal distance f12 of the first lens 110 and the second lens 120 to the focal distance f of the wide-angle lens 1000 as less than -1.000, it is easier to correct various aberrations.

[0144] Furthermore, in conditions 2-3, by further setting the ratio of the combined focal distance f12 of the first lens 110 and the second lens 120 to the focal distance f of the wide-angle lens 1000 as a whole to less than -1.200, it becomes even easier to correct various aberrations.

[0145] Furthermore, as shown in Table 3, the radius of curvature R21 of the object-side lens surface (third surface 3) of the second lens 120 is 45.562 mm, and the radius of curvature R22 of the image-side lens surface (fourth surface 4) of the second lens 120 is 1.309 mm, which satisfies the following conditions 2-4:

[0146] 0.890<(R21+R22) / (R21-R22)<1.500,

[0147] And it also meets the following conditions 2-5:

[0148] 1.000<(R21+R22) / (R21-R22)<1.400.

[0149] In conditions 2-4, by setting (R21+R22) / (R21-R22) to be greater than 0.890, the optical power of the second lens 120 can be avoided to be too strong, and various aberrations can be easily corrected appropriately, thereby easily obtaining excellent optical characteristics. In addition, by setting (R21+R22) / (R21-R22) to be less than 1.500, it can be ensured that the second lens 120 has sufficient negative optical power, thereby easily expanding the maximum half field of view of the wide-angle lens 1000 as a whole.

[0150] Furthermore, in conditions 2-5, by further setting (R21+R22) / (R21-R22) to be greater than 1.000, it is possible to further avoid excessive optical power of the second lens 120, making it easier to properly correct various aberrations and thus more likely to obtain excellent optical characteristics. In addition, by further setting (R21+R22) / (R21-R22) to be less than 1.400, it is possible to further ensure that the second lens 120 has sufficient negative optical power, thus making it easier to expand the maximum half field of view of the wide-angle lens as a whole 1000.

[0151] Furthermore, 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 distance f of the wide-angle lens 1000 as a whole is 1.062 mm. Therefore, the following conditions 2-6 are satisfied:

[0152] 11.000 < d / f < 15.000.

[0153] In conditions 2-6, by setting the ratio of the object-image distance d of the wide-angle lens 1000 to the focal distance f of the wide-angle lens 1000 as 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 distance f of the wide-angle lens 1000 as less than 15.000, the overall length of the wide-angle lens 1000 can be prevented from becoming too long, while suppressing the wide-angle lens 1000 from becoming too large.

[0154] In summary, in this embodiment, by constructing the wide-angle lens 1000 in the manner described above, as follows... Figures 6A to 8L As shown, it can appropriately correct various aberrations such as field curvature, magnification chromatic aberration, and coma aberration, and can ensure the overall negative optical power of the wide-angle lens 1000. This makes it easy to correct various aberrations and easy to manufacture the wide-angle lens 1000, thereby reducing the manufacturing cost of the wide-angle lens 1000 and making it easy to miniaturize the wide-angle lens 1000 as a whole.

[0155] (Implementation Method 3)

[0156] Figure 9 This is an explanatory diagram showing the wide-angle lens according to Embodiment 3 of the present invention. Figure 10A This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 3 of the present invention. Figure 10B This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 3 of the present invention. Figure 11A This is an explanatory diagram showing the transverse chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to Embodiment 3 of the present invention. Figure 11B This is an explanatory diagram showing the spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 3 of the present invention. Figures 12A to 12L This is an explanatory diagram illustrating the lateral aberration of the wide-angle lens according to Embodiment 3 of the present invention. Here, in Figure 10A , Figure 10B , Figure 11A , Figure 11B , Figures 12A to 12L In the diagram, the correlation curve for red light R (wavelength 656nm) is labeled R, the correlation curve for green light G (wavelength 588nm) is labeled G, and the correlation curve for blue light B (wavelength 486nm) is labeled B. T represents correlation with the meridional plane, and S represents correlation with the sagittal plane. Furthermore, in... Figures 12A to 12L In the figure, the maximum scale of the vertical axis is ±50.000 μm.

[0157] like Figure 9As shown, the wide-angle lens 1000 includes a first lens 110 (i.e., the first lens 110 is positioned closest to the object side), a second lens 120 (i.e., the second lens 120 is positioned 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 arranged sequentially from the object side (L1 side), wherein the sixth lens 160 and the seventh lens 170 are bonded together with an adhesive to form a combined lens.

[0158] 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, whether the object-side surface and the image-side surface are convex or concave, and whether they are spherical or aspherical) is the same as that of the wide-angle lens in Embodiment 1, it will not be elaborated on here.

[0159] In addition, such as Figure 9 As shown, similar to Embodiment 1, a light-shielding sheet 190 is provided between the second lens 120 and the fourth lens 130, a filter 200 is provided on the image side of the seventh lens 170, and an image sensor 300 is provided on the image side of the filter 200.

[0160] In this embodiment, the overall focal length f (Effective Focal Length) of the lens system is 1.026 mm, the object-to-image distance d (Total Track) is 13.403 mm, the image space F / # is 2.02, the maximum field of view is 109 degrees, and the entrance pupil diameter HEP is 0.508 mm.

[0161] Table 5 shows the physical properties of each facet of the wide-angle lens 1000 of this embodiment, and Tables 6-1 and 6-2 show the aspherical coefficients of each facet of the wide-angle lens 1000 of this embodiment.

[0162] (Table 5)

[0163]

[0164] In Table 5 above, the units for radius of curvature, thickness, focal distance, effective radius, and sag are mm, Nd is the refractive index of light at 587.56 nanometers, νd is the Abbe number, and * indicates an aspherical surface.

[0165] (Table 6-1)

[0166] 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

[0167] (Table 6-2)

[0168] 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

[0169] In Tables 6-1 and 6-2 above, when the lens surface is a convex surface protruding towards the object side or a concave surface recessed towards the object side, the radius of curvature is set to a positive value; when the lens surface is a convex surface protruding towards the image side or a concave surface recessed towards the image side, the radius of curvature is set to a negative value.

[0170] Furthermore, Tables 6-1 and 6-2 above show the aspherical coefficients A4, A6, A8, A10, A12, A14, and A16 when each face has an aspherical shape, as represented by the mathematical formula 1 above.

[0171] Here, as shown in Table 5, in the wide-angle lens 1000, the sagitta Sag22 of the image-side lens surface (i.e., the fourth surface 4) of the second lens 120 is 1.147 mm, and the effective radius sd22 of the fourth surface 4 of the second lens 120 is 1.498 mm, which satisfies the following condition 3-1:

[0172] 0.720<|Sag22 / sd22|<0.900.

[0173] In condition 3-1, by setting the absolute value of Sag22 / sd22 to be greater than 0.720, it is ensured that the second lens 120 has sufficient negative optical power, thereby making it easy to correct various aberrations. In addition, by setting the absolute value of Sag22 / sd22 to be less than 0.900, it is possible to suppress the angle between the peripheral portion of the second lens 120 and the tangent from being too small, thereby making it easier to manufacture the second lens 120, thereby reducing the overall manufacturing cost of the wide-angle lens 1000 and making it easier to miniaturize the wide-angle lens 1000 as a whole.

[0174] Furthermore, as mentioned above, the overall focal distance f of the wide-angle lens 1000 is 1.026 mm. Table 5 shows that the combined focal distance f12 of the first lens 110 and the second lens 120 is -1.467 mm, which satisfies condition 3-2:

[0175] -1.500 < f12 / f < -1.000,

[0176] And it also meets the following condition 3-3:

[0177] -1.500 < f12 / f < -1.200.

[0178] In condition 3-2, by setting the ratio of the combined focal distance f12 of the first lens 110 and the second lens 120 to the focal distance f of the wide-angle lens 1000 as greater than -1.500, it is possible to further ensure that the wide-angle lens 1000 has sufficient negative optical power, thereby expanding the maximum half field of view of the wide-angle lens 1000; in addition, by setting the ratio of the combined focal distance f12 of the first lens 110 and the second lens 120 to the focal distance f of the wide-angle lens 1000 as less than -1.000, it is easier to correct various aberrations.

[0179] Furthermore, in condition 3-3, by further setting the ratio of the combined focal distance f12 of the first lens 110 and the second lens 120 to the focal distance f of the wide-angle lens 1000 as a whole to less than -1.200, it becomes even easier to correct various aberrations.

[0180] Furthermore, as shown in Table 5, the radius of curvature R21 of the object-side lens surface (third surface 3) of the second lens 120 is 35.057 mm, and the radius of curvature R22 of the image-side lens surface (fourth surface 4) of the second lens 120 is 1.388 mm, which satisfies the following conditions 3-4:

[0181] 0.890<(R21+R22) / (R21-R22)<1.500,

[0182] And it also meets the following conditions 3-5:

[0183] 1.000<(R21+R22) / (R21-R22)<1.400.

[0184] In conditions 3-4, by setting (R21+R22) / (R21-R22) to be greater than 0.890, the optical power of the second lens 120 can be avoided, and various aberrations can be easily corrected appropriately, thereby easily obtaining excellent optical characteristics. In addition, by setting (R21+R22) / (R21-R22) to be less than 1.500, it can be ensured that the second lens 120 has sufficient negative optical power, thereby easily expanding the maximum half field of view of the wide-angle lens 1000 as a whole.

[0185] Furthermore, in conditions 3-5, by further setting (R21+R22) / (R21-R22) to be greater than 1.000, it is possible to further avoid excessive optical power of the second lens 120, making it easier to properly correct various aberrations and thus more likely to obtain excellent optical characteristics. In addition, by further setting (R21+R22) / (R21-R22) to be less than 1.400, it is possible to further ensure that the second lens 120 has sufficient negative optical power, thus making it easier to expand the maximum half field of view of the wide-angle lens as a whole 1000.

[0186] 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 distance f of the wide-angle lens 1000 as a whole is 1.026 mm. Therefore, the following conditions 3-6 are satisfied:

[0187] 11.000 < d / f < 15.000.

[0188] In conditions 3-6, by setting the ratio of the object-image distance d of the wide-angle lens 1000 to the focal distance f of the wide-angle lens 1000 as 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 distance f of the wide-angle lens 1000 as less than 15.000, the overall length of the wide-angle lens 1000 can be prevented from becoming too long, while suppressing the wide-angle lens 1000 from becoming too large.

[0189] In summary, in this embodiment, by constructing the wide-angle lens 1000 in the manner described above, as follows... Figures 10A to 12L As shown, it can appropriately correct various aberrations such as field curvature, magnification chromatic aberration, and coma aberration, and can ensure the overall negative optical power of the wide-angle lens 1000. This makes it easy to correct various aberrations and easy to manufacture the wide-angle lens 1000, thereby reducing the manufacturing cost of the wide-angle lens 1000 and making it easy to miniaturize the wide-angle lens 1000 as a whole.

[0190] (Implementation Method 4)

[0191] Figure 13 This is an explanatory diagram showing the wide-angle lens according to Embodiment 4 of the present invention. Figure 14A This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 4 of the present invention. Figure 14B This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 4 of the present invention. Figure 15A This is an explanatory diagram showing the transverse chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to Embodiment 4 of the present invention. Figure 15B This is an explanatory diagram showing the spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 4 of the present invention. Figures 16A to 16L This is an explanatory diagram illustrating the lateral aberration of the wide-angle lens according to Embodiment 4 of the present invention. Here, in Figure 14A , Figure 14B , Figure 15A , Figure 15B , Figures 16A to 16L In the diagram, the correlation curve for red light R (wavelength 656nm) is labeled R, the correlation curve for green light G (wavelength 588nm) is labeled G, and the correlation curve for blue light B (wavelength 486nm) is labeled B. T represents correlation with the meridional plane, and S represents correlation with the sagittal plane. Furthermore, in... Figures 16A to 16L In the figure, the maximum scale of the vertical axis is ±50.000 μm.

[0192] like Figure 13 As shown, the wide-angle lens 1000 includes a first lens 110 (i.e., the first lens 110 is positioned closest to the object side), a second lens 120 (i.e., the second lens 120 is positioned 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 arranged sequentially from the object side (L1 side), wherein the sixth lens 160 and the seventh lens 170 are bonded together with an adhesive to form a combined lens.

[0193] 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, whether the object-side surface and the image-side surface are convex or concave, and whether they are spherical or aspherical) is the same as that of the wide-angle lens in Embodiment 1, it will not be elaborated on here.

[0194] In addition, such as Figure 13 As shown, similar to Embodiment 1, a light-shielding sheet 190 is provided between the second lens 120 and the fourth lens 130, a filter 200 is provided on the image side of the seventh lens 170, and an image sensor 300 is provided on the image side of the filter 200.

[0195] In this embodiment, the overall focal length f (Effective Focal Length) of the lens system is 1.011 mm, the object-to-image distance d (Total Track) is 13.404 mm, the image space F / # is 2.03, the maximum field of view is 109 degrees, and the entrance pupil diameter HEP is 0.498 mm.

[0196] Table 7 shows the physical properties of each facet of the wide-angle lens 1000 of this embodiment, and Tables 8-1 and 8-2 show the aspherical coefficients of each facet of the wide-angle lens 1000 of this embodiment.

[0197] (Table 7)

[0198]

[0199] In Table 7 above, the units for radius of curvature, thickness, focal distance, effective radius, and sag are mm, Nd is the refractive index of light at 587.56 nanometers, νd is the Abbe number, and * indicates an aspherical surface.

[0200] (Table 8-1)

[0201] 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

[0202] (Table 8-2)

[0203] 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

[0204] In Tables 8-1 and 8-2 above, when the lens surface is a convex surface protruding towards the object side or a concave surface recessed towards the object side, the radius of curvature is set to a positive value; when the lens surface is a convex surface protruding towards the image side or a concave surface recessed towards the image side, the radius of curvature is set to a negative value.

[0205] Furthermore, Tables 8-1 and 8-2 above show the aspherical coefficients A4, A6, A8, A10, A12, A14, and A16 when each face has an aspherical shape, as represented by the mathematical formula 1 above.

[0206] Here, as shown in Table 7, in the wide-angle lens 1000, the sagitta Sag22 of the image-side lens surface (i.e., the fourth surface 4) of the second lens 120 is 1.058 mm, and the effective radius sd22 of the fourth surface 4 of the second lens 120 is 1.435 mm, which satisfies the following condition 4-1:

[0207] 0.720<|Sag22 / sd22|<0.900.

[0208] In condition 4-1, by setting the absolute value of Sag22 / sd22 to be greater than 0.720, it is ensured that the second lens 120 has sufficient negative optical power, thereby making it easy to correct various aberrations. In addition, by setting the absolute value of Sag22 / sd22 to be less than 0.900, it is possible to suppress the angle between the peripheral portion of the second lens 120 and the tangent from being too small, thereby making it easier to manufacture the second lens 120, thereby reducing the overall manufacturing cost of the wide-angle lens 1000 and making it easier to miniaturize the wide-angle lens 1000 as a whole.

[0209] Furthermore, as mentioned above, the overall focal distance f of the wide-angle lens 1000 is 1.011 mm. Table 7 shows that the combined focal distance f12 of the first lens 110 and the second lens 120 is -1.347 mm, which satisfies the following condition 4-2:

[0210] -1.500 < f12 / f < -1.000,

[0211] And it also meets the following condition 4-3:

[0212] -1.500 < f12 / f < -1.200.

[0213] In condition 4-2, by setting the ratio of the combined focal distance f12 of the first lens 110 and the second lens 120 to the focal distance f of the wide-angle lens 1000 as a whole to be greater than -1.500, it is possible to further ensure that the wide-angle lens 1000 has sufficient negative optical power, thereby expanding the maximum half field of view of the wide-angle lens 1000; in addition, by setting the ratio of the combined focal distance f12 of the first lens 110 and the second lens 120 to the focal distance f of the wide-angle lens 1000 as a whole to be less than -1.000, it is easier to correct various aberrations.

[0214] Furthermore, in condition 4-3, by further setting the ratio of the combined focal distance f12 of the first lens 110 and the second lens 120 to the focal distance f of the wide-angle lens 1000 as a whole to less than -1.200, it becomes even easier to correct various aberrations.

[0215] Furthermore, as shown in Table 7, the radius of curvature R21 of the object-side lens surface (third surface 3) of the second lens 120 is 23.043 mm, and the radius of curvature R22 of the image-side lens surface (fourth surface 4) of the second lens 120 is 1.291 mm, which satisfies the following condition 4-4:

[0216] 0.890<(R21+R22) / (R21-R22)<1.500,

[0217] And it also meets the following conditions 4-5:

[0218] 1.000<(R21+R22) / (R21-R22)<1.400.

[0219] In condition 4-4, by setting (R21+R22) / (R21-R22) to be greater than 0.890, the optical power of the second lens 120 can be avoided to be too strong, and various aberrations can be easily corrected appropriately, thereby easily obtaining excellent optical characteristics. In addition, by setting (R21+R22) / (R21-R22) to be less than 1.500, it can be ensured that the second lens 120 has sufficient negative optical power, thereby easily expanding the maximum half field of view of the wide-angle lens 1000 as a whole.

[0220] Furthermore, in conditions 4-5, by further setting (R21+R22) / (R21-R22) to be greater than 1.000, it is possible to further avoid excessive optical power of the second lens 120, making it easier to properly correct various aberrations and thus more likely to obtain excellent optical characteristics. In addition, by further setting (R21+R22) / (R21-R22) to be less than 1.400, it is possible to further ensure that the second lens 120 has sufficient negative optical power, thus making it easier to expand the maximum half field of view of the wide-angle lens as a whole 1000.

[0221] 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 distance f of the wide-angle lens 1000 as a whole is 1.011 mm. Therefore, the following conditions 4-6 are satisfied:

[0222] 11.000 < d / f < 15.000.

[0223] In conditions 4-6, by setting the ratio of the object-image distance d of the wide-angle lens 1000 to the focal distance f of the wide-angle lens 1000 as 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 distance f of the wide-angle lens 1000 as less than 15.000, the overall length of the wide-angle lens 1000 can be prevented from becoming too long, while suppressing the wide-angle lens 1000 from becoming too large.

[0224] In summary, in this embodiment, by constructing the wide-angle lens 1000 in the manner described above, as follows... Figures 14A to 16L As shown, it can appropriately correct various aberrations such as field curvature, magnification chromatic aberration, and coma aberration, and can ensure the overall negative optical power of the wide-angle lens 1000. This makes it easy to correct various aberrations and easy to manufacture the wide-angle lens 1000, thereby reducing the manufacturing cost of the wide-angle lens 1000 and making it easy to miniaturize the wide-angle lens 1000 as a whole.

[0225] (Implementation Method 5)

[0226] Figure 17 This is an explanatory diagram showing the wide-angle lens according to Embodiment 5 of the present invention. Figure 18A This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 5 of the present invention. Figure 18B This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 5 of the present invention. Figure 19A This is an explanatory diagram showing the transverse chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to Embodiment 5 of the present invention. Figure 19B This is an explanatory diagram showing the spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 5 of the present invention. Figures 20A to 20LThis is an explanatory diagram illustrating the lateral aberration of the wide-angle lens according to Embodiment 5 of the present invention. Here, in Figure 18A , Figure 18B , Figure 19A , Figure 19B , Figures 20A to 20L In the diagram, the correlation curve for red light R (wavelength 656nm) is labeled R, the correlation curve for green light G (wavelength 588nm) is labeled G, and the correlation curve for blue light B (wavelength 486nm) is labeled B. T represents correlation with the meridional plane, and S represents correlation with the sagittal plane. Furthermore, in... Figures 20A to 20L In the figure, the maximum scale of the vertical axis is ±50.000 μm.

[0227] like Figure 17 As shown, the wide-angle lens 1000 includes a first lens 110 (i.e., the first lens 110 is positioned closest to the object side), a second lens 120 (i.e., the second lens 120 is positioned 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 arranged sequentially from the object side (L1 side), wherein the sixth lens 160 and the seventh lens 170 are bonded together with an adhesive to form a combined lens.

[0228] 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, whether the object-side surface and the image-side surface are convex or concave, and whether they are spherical or aspherical) is the same as that of the wide-angle lens in Embodiment 1, it will not be elaborated on here.

[0229] In addition, such as Figure 17 As shown, similar to Embodiment 1, a light-shielding sheet 190 is provided between the second lens 120 and the fourth lens 130, a filter 200 is provided on the image side of the seventh lens 170, and an image sensor 300 is provided on the image side of the filter 200.

[0230] In this embodiment, the overall focal length f (Effective Focal Length) of the lens system is 1.021 mm, the object-to-image distance d (Total Track) is 13.398 mm, the image space F / # is 2, the maximum field of view is 108 degrees, and the entrance pupil diameter HEP is 0.511 mm.

[0231] Table 9 shows the physical properties of each facet of the wide-angle lens 1000 of this embodiment, and Tables 10-1 and 10-2 show the aspherical coefficients of each facet of the wide-angle lens 1000 of this embodiment.

[0232] (Table 9)

[0233]

[0234] In Table 9 above, the units for radius of curvature, thickness, focal distance, effective radius, and sag are mm, Nd is the refractive index of light at 587.56 nanometers, νd is the Abbe number, and * indicates an aspherical surface.

[0235] (Table 10-1)

[0236] 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

[0237] (Table 10-2)

[0238] 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

[0239] In Tables 10-1 and 10-2 above, when the lens surface is a convex surface protruding towards the object side or a concave surface recessed towards the object side, the radius of curvature is set to a positive value; when the lens surface is a convex surface protruding towards the image side or a concave surface recessed towards the image side, the radius of curvature is set to a negative value.

[0240] Furthermore, Tables 10-1 and 10-2 above show the aspherical coefficients A4, A6, A8, A10, A12, A14, and A16 when the aspherical shape of each face is represented by the mathematical formula 1 above.

[0241] Here, as shown in Table 9, in the wide-angle lens 1000, the sagitta Sag22 of the image-side lens surface (i.e., the fourth surface 4) of the second lens 120 is 1.206 mm, and the effective radius sd22 of the fourth surface 4 of the second lens 120 is 1.460 mm, which satisfies the following condition 5-1:

[0242] 0.720<|Sag22 / sd22|<0.900.

[0243] In condition 5-1, by setting the absolute value of Sag22 / sd22 to be greater than 0.720, it is ensured that the second lens 120 has sufficient negative optical power, thereby making it easy to correct various aberrations. In addition, by setting the absolute value of Sag22 / sd22 to be less than 0.900, it is possible to suppress the angle between the peripheral portion of the second lens 120 and the tangent from being too small, thereby making it easier to manufacture the second lens 120, thereby reducing the overall manufacturing cost of the wide-angle lens 1000 and making it easier to miniaturize the wide-angle lens 1000 as a whole.

[0244] Furthermore, as mentioned above, the overall focal distance f of the wide-angle lens 1000 is 1.021 mm. Table 9 shows that the combined focal distance f12 of the first lens 110 and the second lens 120 is -1.258 mm, which satisfies the following condition 5-2:

[0245] -1.500 < f12 / f < -1.000,

[0246] And it also meets the following condition 5-3:

[0247] -1.500 < f12 / f < -1.200.

[0248] In condition 5-2, by setting the ratio of the combined focal distance f12 of the first lens 110 and the second lens 120 to the focal distance f of the wide-angle lens 1000 as greater than -1.500, it is possible to further ensure that the wide-angle lens 1000 has sufficient negative optical power, thereby expanding the maximum half field of view of the wide-angle lens 1000; in addition, by setting the ratio of the combined focal distance f12 of the first lens 110 and the second lens 120 to the focal distance f of the wide-angle lens 1000 as less than -1.000, it is easier to correct various aberrations.

[0249] Furthermore, in condition 5-3, by further setting the ratio of the combined focal distance f12 of the first lens 110 and the second lens 120 to the focal distance f of the wide-angle lens 1000 as a whole to less than -1.200, it becomes even easier to correct various aberrations.

[0250] Furthermore, as shown in Table 9, the radius of curvature R21 of the object-side lens surface (third surface 3) of the second lens 120 is 21.109 mm, and the radius of curvature R22 of the image-side lens surface (fourth surface 4) of the second lens 120 is 1.226 mm, which satisfies the following condition 5-4:

[0251] 0.890<(R21+R22) / (R21-R22)<1.500,

[0252] And it also meets the following condition 5-5:

[0253] 1.000<(R21+R22) / (R21-R22)<1.400.

[0254] In condition 5-4, by setting (R21+R22) / (R21-R22) to be greater than 0.890, the optical power of the second lens 120 can be avoided to be too strong, and various aberrations can be easily corrected appropriately, thereby easily obtaining excellent optical characteristics. In addition, by setting (R21+R22) / (R21-R22) to be less than 1.500, it can be ensured that the second lens 120 has sufficient negative optical power, thereby easily expanding the maximum half field of view of the wide-angle lens 1000 as a whole.

[0255] Furthermore, in condition 5-5, by further setting (R21+R22) / (R21-R22) to be greater than 1.000, it is possible to further avoid excessive optical power of the second lens 120, making it easier to properly correct various aberrations and thus more likely to obtain excellent optical characteristics. In addition, by further setting (R21+R22) / (R21-R22) to be less than 1.400, it is possible to further ensure that the second lens 120 has sufficient negative optical power, thus making it easier to expand the maximum half field of view of the wide-angle lens as a whole 1000.

[0256] 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 distance f of the wide-angle lens 1000 as a whole is 1.021 mm. Therefore, the following conditions 5-6 are satisfied:

[0257] 11.000 < d / f < 15.000.

[0258] In conditions 5-6, by setting the ratio of the object-image distance d of the wide-angle lens 1000 to the focal distance f of the wide-angle lens 1000 as 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 distance f of the wide-angle lens 1000 as less than 15.000, the overall length of the wide-angle lens 1000 can be prevented from becoming too long, while suppressing the wide-angle lens 1000 from becoming too large.

[0259] In summary, in this embodiment, by constructing the wide-angle lens 1000 in the manner described above, as follows... Figures 18A to 20L As shown, it can appropriately correct various aberrations such as field curvature, magnification chromatic aberration, and coma aberration, and can ensure the overall negative optical power of the wide-angle lens 1000. This makes it easy to correct various aberrations and easy to manufacture the wide-angle lens 1000, thereby reducing the manufacturing cost of the wide-angle lens 1000 and making it easy to miniaturize the wide-angle lens 1000 as a whole.

[0260] (Implementation Method 6)

[0261] Figure 21This is an explanatory diagram showing the wide-angle lens according to Embodiment 6 of the present invention. Figure 22A This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 6 of the present invention. Figure 22B This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 6 of the present invention. Figure 23A This is an explanatory diagram showing the transverse chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to Embodiment 6 of the present invention. Figure 23B This is an explanatory diagram showing the spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 6 of the present invention. Figures 24A to 24L This is an explanatory diagram illustrating the lateral aberration of the wide-angle lens according to Embodiment 6 of the present invention. Here, in Figure 22A , Figure 22B , Figure 23A , Figure 23B , Figures 24A to 24L In the diagram, the correlation curve for red light R (wavelength 656nm) is labeled R, the correlation curve for green light G (wavelength 588nm) is labeled G, and the correlation curve for blue light B (wavelength 486nm) is labeled B. T represents correlation with the meridional plane, and S represents correlation with the sagittal plane. Furthermore, in... Figures 24A to 24L In the figure, the maximum scale of the vertical axis is ±50.000 μm.

[0262] like Figure 21 As shown, the wide-angle lens 1000 includes a first lens 110 (i.e., the first lens 110 is positioned closest to the object side), a second lens 120 (i.e., the second lens 120 is positioned 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 arranged sequentially from the object side (L1 side), wherein the sixth lens 160 and the seventh lens 170 are bonded together with an adhesive to form a combined lens.

[0263] 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, whether the object-side surface and the image-side surface are convex or concave, and whether they are spherical or aspherical) is the same as that of the wide-angle lens in Embodiment 1, it will not be elaborated on here.

[0264] In addition, such as Figure 21 As shown, similar to Embodiment 1, a light-shielding sheet 190 is provided between the second lens 120 and the fourth lens 130, a filter 200 is provided on the image side of the seventh lens 170, and an image sensor 300 is provided on the image side of the filter 200.

[0265] In this embodiment, the overall focal length f (Effective Focal Length) of the lens system is 1.018 mm, the object-to-image distance d (Total Track) is 13.383 mm, the image space F / # is 2, the maximum field of view is 108 degrees, and the entrance pupil diameter HEP is 0.509 mm.

[0266] Table 11 shows the physical properties of each facet of the wide-angle lens 1000 of this embodiment, and Tables 12-1 and 12-2 show the aspherical coefficients of each facet of the wide-angle lens 1000 of this embodiment.

[0267] (Table 11)

[0268]

[0269] In Table 11 above, the units for radius of curvature, thickness, focal distance, effective radius, and sag are mm, Nd is the refractive index of light at 587.56 nanometers, νd is the Abbe number, and * indicates an aspherical surface.

[0270] (Table 12-1)

[0271] 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

[0272] (Table 12-2)

[0273] 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

[0274] In Tables 12-1 and 12-2 above, when the lens surface is a convex surface protruding towards the object side or a concave surface recessed towards the object side, the radius of curvature is set to a positive value; when the lens surface is a convex surface protruding towards the image side or a concave surface recessed towards the image side, the radius of curvature is set to a negative value.

[0275] Furthermore, Tables 12-1 and 12-2 above show the aspherical coefficients A4, A6, A8, A10, A12, A14, and A16 when each face has an aspherical shape, as represented by the mathematical formula 1 above.

[0276] Here, as shown in Table 11, in the wide-angle lens 1000, the sagitta Sag22 of the image-side lens surface (i.e., the fourth surface 4) of the second lens 120 is 1.100 mm, and the effective radius sd22 of the fourth surface 4 of the second lens 120 is 1.350 mm, which satisfies the following condition 6-1:

[0277] 0.720<|Sag22 / sd22|<0.900.

[0278] In condition 6-1, by setting the absolute value of Sag22 / sd22 to be greater than 0.720, it is ensured that the second lens 120 has sufficient negative optical power, thereby making it easy to correct various aberrations. In addition, by setting the absolute value of Sag22 / sd22 to be less than 0.900, it is possible to suppress the angle between the peripheral portion of the second lens 120 and the tangent from being too small, thereby making it easier to manufacture the second lens 120, thereby reducing the overall manufacturing cost of the wide-angle lens 1000 and making it easier to miniaturize the wide-angle lens 1000 as a whole.

[0279] Furthermore, as mentioned above, the overall focal distance f of the wide-angle lens 1000 is 1.018 mm. Table 11 shows that the combined focal distance f12 of the first lens 110 and the second lens 120 is -1.310 mm, which satisfies the following condition 6-2:

[0280] -1.500 < f12 / f < -1.000,

[0281] And it also meets the following condition 6-3:

[0282] -1.500 < f12 / f < -1.200.

[0283] In condition 6-2, by setting the ratio of the combined focal distance f12 of the first lens 110 and the second lens 120 to the focal distance f of the wide-angle lens 1000 as a whole to be greater than -1.500, it is possible to further ensure that the wide-angle lens 1000 has sufficient negative optical power, thereby expanding the maximum half field of view of the wide-angle lens 1000; in addition, by setting the ratio of the combined focal distance f12 of the first lens 110 and the second lens 120 to the focal distance f of the wide-angle lens 1000 as a whole to be less than -1.000, it is easier to correct various aberrations.

[0284] Furthermore, in condition 6-3, by further setting the ratio of the combined focal distance f12 of the first lens 110 and the second lens 120 to the focal distance f of the wide-angle lens 1000 as a whole to less than -1.200, it becomes even easier to correct various aberrations.

[0285] Furthermore, as shown in Table 11, the radius of curvature R21 of the object-side lens surface (third surface 3) of the second lens 120 is 9.149 mm, and the radius of curvature R22 of the image-side lens surface (fourth surface 4) of the second lens 120 is 1.191 mm, which satisfies the following condition 6-4:

[0286] 0.890<(R21+R22) / (R21-R22)<1.500,

[0287] And it also meets the following condition 6-5:

[0288] 1.000<(R21+R22) / (R21-R22)<1.400.

[0289] In condition 6-4, by setting (R21+R22) / (R21-R22) to be greater than 0.890, the optical power of the second lens 120 can be avoided to be too strong, and various aberrations can be easily corrected appropriately, thereby easily obtaining excellent optical characteristics. In addition, by setting (R21+R22) / (R21-R22) to be less than 1.500, it can be ensured that the second lens 120 has sufficient negative optical power, thereby easily expanding the maximum half field of view of the wide-angle lens 1000 as a whole.

[0290] Furthermore, in condition 6-5, by further setting (R21+R22) / (R21-R22) to be greater than 1.000, it is possible to further avoid excessive optical power of the second lens 120, making it easier to properly correct various aberrations and thus more likely to obtain excellent optical characteristics. In addition, by further setting (R21+R22) / (R21-R22) to be less than 1.400, it is possible to further ensure that the second lens 120 has sufficient negative optical power, thus making it easier to expand the maximum half field of view of the wide-angle lens as a whole 1000.

[0291] 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 distance f of the wide-angle lens 1000 as a whole is 1.018 mm. Therefore, the following condition 6-6 is satisfied:

[0292] 11.000 < d / f < 15.000.

[0293] In condition 6-6, by setting the ratio of the object-image distance d of the wide-angle lens 1000 to the focal distance f of the wide-angle lens 1000 as 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 distance f of the wide-angle lens 1000 as less than 15.000, the overall length of the wide-angle lens 1000 can be prevented from becoming too long, while the wide-angle lens 1000 can be suppressed from becoming too large.

[0294] In summary, in this embodiment, by constructing the wide-angle lens 1000 in the manner described above, as follows... Figures 22A to 24L As shown, it can appropriately correct various aberrations such as field curvature, magnification chromatic aberration, and coma aberration, and can ensure the overall negative optical power of the wide-angle lens 1000. This makes it easy to correct various aberrations and easy to manufacture the wide-angle lens 1000, thereby reducing the manufacturing cost of the wide-angle lens 1000 and making it easy to miniaturize the wide-angle lens 1000 as a whole.

[0295] (Implementation Method 7)

[0296] Figure 25 This is an explanatory diagram showing the wide-angle lens according to Embodiment 7 of the present invention. Figure 26A This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 7 of the present invention. Figure 26B This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 7 of the present invention. Figure 27A This is an explanatory diagram showing the transverse chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to Embodiment 7 of the present invention. Figure 27B This is an explanatory diagram showing the spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 7 of the present invention. Figures 28A to 28L This is an explanatory diagram illustrating the lateral aberration of the wide-angle lens according to Embodiment 7 of the present invention. Here, in Figure 26A , Figure 26B , Figure 27A , Figure 27B , Figures 28A to 28L In the diagram, the correlation curve for red light R (wavelength 656nm) is labeled R, the correlation curve for green light G (wavelength 588nm) is labeled G, and the correlation curve for blue light B (wavelength 486nm) is labeled B. T represents correlation with the meridional plane, and S represents correlation with the sagittal plane. Furthermore, in... Figures 28A to 28L In the figure, the maximum scale of the vertical axis is ±50.000 μm.

[0297] 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 arranged sequentially from the object side (L1 side). The sixth lens 160 and the seventh lens 170 are bonded together with an adhesive to form a joint lens.

[0298] Here, since the basic structure of the wide-angle lens 1000 in this embodiment (i.e., whether the first lens 110 (i.e., the first lens 110 is positioned closest to the object side), the second lens 120 (i.e., the second lens 120 is positioned adjacent to the image side of the first lens 110), 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, are glass lenses or plastic lenses, and whether the object-side surface and the image-side surface are convex or concave, and whether they are spherical or aspherical) is the same as that of the wide-angle lens in Embodiment 1, it will not be elaborated in detail here.

[0299] In addition, such as Figure 25As shown, similar to Embodiment 1, a light-shielding sheet 190 is provided between the second lens 120 and the fourth lens 130, a filter 200 is provided on the image side of the seventh lens 170, and an image sensor 300 is provided on the image side of the filter 200.

[0300] In this embodiment, the overall focal length f (Effective Focal Length) of the lens system is 1.019 mm, the object-to-image distance d (Total Track) is 13.381 mm, the image space F / # is 2.0163, the maximum field of view is 108 degrees, and the entrance pupil diameter HEP is 0.505 mm.

[0301] Table 13 shows the physical properties of each facet of the wide-angle lens 1000 of this embodiment, and Tables 14-1 and 14-2 show the aspherical coefficients of each facet of the wide-angle lens 1000 of this embodiment.

[0302] (Table 13)

[0303]

[0304] In Table 11 above, the units for radius of curvature, thickness, focal distance, effective radius, and sag are mm, Nd is the refractive index of light at 587.56 nanometers, νd is the Abbe number, and * indicates an aspherical surface.

[0305] (Table 14-1)

[0306] 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

[0307] (Table 14-2)

[0308] 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

[0309] In Tables 14-1 and 14-2 above, when the lens surface is a convex surface protruding towards the object side or a concave surface recessed towards the object side, the radius of curvature is set to a positive value; when the lens surface is a convex surface protruding towards the image side or a concave surface recessed towards the image side, the radius of curvature is set to a negative value.

[0310] Furthermore, Tables 14-1 and 14-2 above show the aspherical coefficients A4, A6, A8, A10, A12, A14, and A16 when the aspherical shape of each face is represented by the mathematical formula 1 above.

[0311] Here, as shown in Table 13, in the wide-angle lens 1000, the sagitta Sag22 of the image-side lens surface (i.e., the fourth surface 4) of the second lens 120 is 1.100 mm, and the effective radius sd22 of the fourth surface 4 of the second lens 120 is 1.350 mm, which satisfies the following condition 7-1:

[0312] 0.720<|Sag22 / sd22|<0.900.

[0313] In condition 7-1, by setting the absolute value of Sag22 / sd22 to be greater than 0.720, it is ensured that the second lens 120 has sufficient negative optical power, thereby making it easy to correct various aberrations. In addition, by setting the absolute value of Sag22 / sd22 to be less than 0.900, it is possible to suppress the angle between the peripheral portion of the second lens 120 and the tangent from being too small, thereby making it easier to manufacture the second lens 120, thereby reducing the overall manufacturing cost of the wide-angle lens 1000 and making it easier to miniaturize the wide-angle lens 1000 as a whole.

[0314] Furthermore, as mentioned above, the overall focal distance f of the wide-angle lens 1000 is 1.019 mm. Table 13 shows that the combined focal distance f12 of the first lens 110 and the second lens 120 is -1.310 mm, which satisfies the following condition 7-2:

[0315] -1.500 < f12 / f < -1.000,

[0316] And it also meets the following condition 7-3:

[0317] -1.500 < f12 / f < -1.200.

[0318] In condition 7-2, by setting the ratio of the combined focal distance f12 of the first lens 110 and the second lens 120 to the focal distance f of the wide-angle lens 1000 as a whole to be greater than -1.500, it is possible to further ensure that the wide-angle lens 1000 has sufficient negative optical power, thereby expanding the maximum half field of view of the wide-angle lens 1000; in addition, by setting the ratio of the combined focal distance f12 of the first lens 110 and the second lens 120 to the focal distance f of the wide-angle lens 1000 as a whole to be less than -1.000, it is easier to correct various aberrations.

[0319] Furthermore, in condition 7-3, by further setting the ratio of the combined focal distance f12 of the first lens 110 and the second lens 120 to the focal distance f of the wide-angle lens 1000 as a whole to less than -1.200, it becomes even easier to correct various aberrations.

[0320] Furthermore, as shown in Table 13, the radius of curvature R21 of the object-side lens surface (third surface 3) of the second lens 120 is 9.138 mm, and the radius of curvature R22 of the image-side lens surface (fourth surface 4) of the second lens 120 is 1.191 mm, which satisfies the following condition 7-4:

[0321] 0.890<(R21+R22) / (R21-R22)<1.500,

[0322] And it also meets the following condition 7-5:

[0323] 1.000<(R21+R22) / (R21-R22)<1.400.

[0324] In condition 7-4, by setting (R21+R22) / (R21-R22) to be greater than 0.890, the optical power of the second lens 120 can be avoided to be too strong, and various aberrations can be easily corrected appropriately, thereby easily obtaining excellent optical characteristics. In addition, by setting (R21+R22) / (R21-R22) to be less than 1.500, it can be ensured that the second lens 120 has sufficient negative optical power, thereby easily expanding the maximum half field of view of the wide-angle lens 1000 as a whole.

[0325] Furthermore, in condition 7-5, by further setting (R21+R22) / (R21-R22) to be greater than 1.000, it is possible to further avoid excessive optical power of the second lens 120, making it easier to properly correct various aberrations and thus more likely to obtain excellent optical characteristics. In addition, by further setting (R21+R22) / (R21-R22) to be less than 1.400, it is possible to further ensure that the second lens 120 has sufficient negative optical power, thus making it easier to expand the maximum half field of view of the wide-angle lens as a whole 1000.

[0326] 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 distance f of the wide-angle lens 1000 as a whole is 1.019 mm. Therefore, the following conditions 7-6 are satisfied:

[0327] 11.000 < d / f < 15.000.

[0328] In conditions 7-6, by setting the ratio of the object-image distance d of the wide-angle lens 1000 to the focal distance f of the wide-angle lens 1000 as 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 distance f of the wide-angle lens 1000 as less than 15.000, the overall length of the wide-angle lens 1000 can be prevented from becoming too long, while suppressing the wide-angle lens 1000 from becoming too large.

[0329] In summary, in this embodiment, by constructing the wide-angle lens 1000 in the manner described above, as follows... Figures 26A to 28L As shown, it can appropriately correct various aberrations such as field curvature, magnification chromatic aberration, and coma aberration, and can ensure the overall negative optical power of the wide-angle lens 1000. This makes it easy to correct various aberrations and easy to manufacture the wide-angle lens 1000, thereby reducing the manufacturing cost of the wide-angle lens 1000 and making it easy to miniaturize the wide-angle lens 1000 as a whole.

[0330] (Implementation Method 8)

[0331] Figure 29 This is an explanatory diagram showing the wide-angle lens according to Embodiment 8 of the present invention. Figure 30A This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 8 of the present invention. Figure 30B This is an explanatory diagram showing the field curvature and distortion of the wide-angle lens according to Embodiment 8 of the present invention. Figure 31A This is an explanatory diagram showing the transverse chromatic aberration (lateral chromatic aberration) of the wide-angle lens according to Embodiment 8 of the present invention. Figure 31B This is an explanatory diagram showing the spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 8 of the present invention. Figures 32A to 32L This is an explanatory diagram illustrating the lateral aberration of the wide-angle lens according to Embodiment 8 of the present invention. Here, in Figure 30A , Figure 30B , Figure 31A , Figure 31B , Figures 32A to 32L In the diagram, the correlation curve for red light R (wavelength 656nm) is labeled R, the correlation curve for green light G (wavelength 588nm) is labeled G, and the correlation curve for blue light B (wavelength 486nm) is labeled B. T represents correlation with the meridional plane, and S represents correlation with the sagittal plane. Furthermore, in... Figures 32A to 32L In the figure, the maximum scale of the vertical axis is ±50.000 μm.

[0332] like Figure 29 As shown, the wide-angle lens 1000 includes a first lens 110 (i.e., the first lens 110 is positioned closest to the object side), a second lens 120 (i.e., the second lens 120 is positioned 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 arranged sequentially from the object side (L1 side), wherein the sixth lens 160 and the seventh lens 170 are bonded together with an adhesive to form a combined lens.

[0333] 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, whether the object-side surface and the image-side surface are convex or concave, and whether they are spherical or aspherical) is the same as that of the wide-angle lens in Embodiment 1, it will not be elaborated on here.

[0334] In addition, such as Figure 29 As shown, similar to Embodiment 1, a light-shielding sheet 190 is provided between the second lens 120 and the fourth lens 130, a filter 200 is provided on the image side of the seventh lens 170, and an image sensor 300 is provided on the image side of the filter 200.

[0335] In this embodiment, the overall focal length f (Effective Focal Length) of the lens system is 1.019 mm, the object-to-image distance d (Total Track) is 13.397 mm, the image space F / # is 2.012, the maximum field of view is 108.004 degrees, and the entrance pupil diameter HEP is 0.506 mm.

[0336] Table 15 shows the physical properties of each facet of the wide-angle lens 1000 of this embodiment, and Tables 16-1 and 16-2 show the aspherical coefficients of each facet of the wide-angle lens 1000 of this embodiment.

[0337] (Table 15)

[0338]

[0339] In Table 15 above, the units for radius of curvature, thickness, focal distance, effective radius, and sag are mm, Nd is the refractive index of light at 587.56 nanometers, νd is the Abbe number, and * indicates an aspherical surface.

[0340] (Table 16-1)

[0341] 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

[0342] (Table 16-2)

[0343] 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

[0344] In Tables 16-1 and 16-2 above, when the lens surface is a convex surface protruding towards the object side or a concave surface recessed towards the object side, the radius of curvature is set to a positive value; when the lens surface is a convex surface protruding towards the image side or a concave surface recessed towards the image side, the radius of curvature is set to a negative value.

[0345] Furthermore, Tables 16-1 and 16-2 above show the aspherical coefficients A4, A6, A8, A10, A12, A14, and A16 when each face has an aspherical shape, as represented by the mathematical formula 1 above.

[0346] Here, as shown in Table 15, in the wide-angle lens 1000, the sagitta Sag22 of the image-side lens surface (i.e., the fourth surface 4) of the second lens 120 is 1.095 mm, and the effective radius sd22 of the fourth surface 4 of the second lens 120 is 1.419 mm, which satisfies the following condition 8-1:

[0347] 0.720<|Sag22 / sd22|<0.900.

[0348] In condition 8-1, by setting the absolute value of Sag22 / sd22 to be greater than 0.720, it is ensured that the second lens 120 has sufficient negative optical power, thereby making it easy to correct various aberrations. In addition, by setting the absolute value of Sag22 / sd22 to be less than 0.900, it is possible to suppress the angle between the peripheral portion of the second lens 120 and the tangent from being too small, thereby making it easier to manufacture the second lens 120, thereby reducing the overall manufacturing cost of the wide-angle lens 1000 and making it easier to miniaturize the wide-angle lens 1000 as a whole.

[0349] Furthermore, as mentioned above, the overall focal distance f of the wide-angle lens 1000 is 1.019 mm. Table 15 shows that the combined focal distance f12 of the first lens 110 and the second lens 120 is -1.415 mm, which satisfies the following condition 8-2:

[0350] -1.500 < f12 / f < -1.000,

[0351] And it also meets the following condition 8-3:

[0352] -1.500 < f12 / f < -1.200.

[0353] In condition 8-2, by setting the ratio of the combined focal distance f12 of the first lens 110 and the second lens 120 to the focal distance f of the wide-angle lens 1000 as a whole to be greater than -1.500, it is possible to further ensure that the wide-angle lens 1000 has sufficient negative optical power, thereby expanding the maximum half field of view of the wide-angle lens 1000; in addition, by setting the ratio of the combined focal distance f12 of the first lens 110 and the second lens 120 to the focal distance f of the wide-angle lens 1000 as a whole to be less than -1.000, it is easier to correct various aberrations.

[0354] Furthermore, in condition 8-3, by further setting the ratio of the combined focal distance f12 of the first lens 110 and the second lens 120 to the focal distance f of the wide-angle lens 1000 as a whole to less than -1.200, it becomes even easier to correct various aberrations.

[0355] Furthermore, as shown in Table 15, the radius of curvature R21 of the object-side lens surface (third surface 3) of the second lens 120 is 7.693 mm, and the radius of curvature R22 of the image-side lens surface (fourth surface 4) of the second lens 120 is 1.237 mm, which satisfies the following condition 8-4:

[0356] 0.890<(R21+R22) / (R21-R22)<1.500,

[0357] And it also meets the following condition 8-5:

[0358] 1.000<(R21+R22) / (R21-R22)<1.400.

[0359] In condition 8-4, by setting (R21+R22) / (R21-R22) to be greater than 0.890, the optical power of the second lens 120 can be avoided to be too strong, and various aberrations can be easily corrected appropriately, thereby easily obtaining excellent optical characteristics. In addition, by setting (R21+R22) / (R21-R22) to be less than 1.500, it can be ensured that the second lens 120 has sufficient negative optical power, thereby easily expanding the maximum half field of view of the wide-angle lens 1000 as a whole.

[0360] Furthermore, in condition 8-5, by further setting (R21+R22) / (R21-R22) to be greater than 1.000, it is possible to further avoid excessive optical power of the second lens 120, and it is easier to properly correct various aberrations, thereby making it easier to obtain excellent optical characteristics. In addition, by further setting (R21+R22) / (R21-R22) to be less than 1.400, it is possible to further ensure that the second lens 120 has sufficient negative optical power, thereby making it easier to expand the maximum half field of view of the wide-angle lens as a whole 1000.

[0361] 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 distance f of the wide-angle lens 1000 as a whole is 1.019 mm. Therefore, the following conditions 8-6 are satisfied:

[0362] 11.000 < d / f < 15.000.

[0363] In conditions 8-6, by setting the ratio of the object-image distance d of the wide-angle lens 1000 to the focal distance f of the wide-angle lens 1000 as 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 distance f of the wide-angle lens 1000 as less than 15.000, the overall length of the wide-angle lens 1000 can be prevented from becoming too long, while the wide-angle lens 1000 can be suppressed from becoming too large.

[0364] In summary, in this embodiment, by constructing the wide-angle lens 1000 in the manner described above, as follows... Figures 30A to 32L As shown, it can appropriately correct various aberrations such as field curvature, magnification chromatic aberration, and coma aberration, and can ensure the overall negative optical power of the wide-angle lens 1000. This makes it easy to correct various aberrations and easy to manufacture the wide-angle lens 1000, thereby reducing the manufacturing cost of the wide-angle lens 1000 and making it easy to miniaturize the wide-angle lens 1000 as a whole.

[0365] The present invention has been described above by way of example with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above embodiments.

[0366] For example, in the above embodiments, the shape of the first surface 1 of the first lens 110, the shape of the third surface 3 of the second lens 120, the shape of the fifth surface 5 of the third lens 130, the shape of the seventh surface 7 of the fourth lens 140, and the shape of the twelfth surface 12 of the sixth lens 160 can be appropriately changed as needed.

[0367] Furthermore, in the above embodiments, the first lens 110 and the fifth lens 150 may also be made 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 also be made of glass lenses.

[0368] Furthermore, in the above embodiment, the case where the wide-angle lens 1000 has seven lenses as a lens group has been described, but the number of lenses of the wide-angle lens 1000 is not limited to seven, and may be set to six or less or eight or more depending on actual needs.

Claims

1. A wide-angle lens, characterized in that, The wide-angle lens includes a lens group and an aperture, wherein multiple lenses in the lens group are arranged sequentially from the object side in a manner that sandwiches the aperture. The lens group comprises seven lenses, and the seven lenses and the aperture are arranged sequentially from the object side in the order of first lens, second lens, third lens, fourth lens, aperture, fifth lens, sixth lens, and seventh lens. The first lens is positioned closest to the object side, and it is a negative lens with its convex surface facing the object side and its concave surface facing the image side. The second lens is disposed adjacent to the first lens on the image side, and the second lens is a negative lens with its convex surface facing the object side and its concave surface facing the image side as an aspherical surface. The third lens is a positive lens with its concave surface facing the object side and its convex surface facing the image side. The fourth lens is a positive lens with its convex surface facing the image side. The fifth lens is a positive lens with its convex surface facing the object side and its convex surface facing the image side. The sixth lens is a negative lens with its concave surface facing the object side and its concave surface facing the image side. The seventh lens is a positive lens with its convex surface facing the object side and its convex surface facing the image side. The sixth lens and the seventh lens constitute a combined lens. When the sagitta of the image-side lens surface of the second lens is set to Sag22 and the effective radius of the image-side lens surface of the second lens is set to sd22, the following relationship is satisfied: 0.720<|Sag22 / sd22|<0.

900.

2. The wide-angle lens as described in claim 1, characterized in that, When the combined focal distance between the first lens and the second lens is set to f12, and the focal distance of the entire wide-angle lens is set to f, the following relationship is satisfied: -1.500 < f12 / f < -1.

000.

3. The wide-angle lens as described in claim 2, characterized in that, -1.500 < f12 / f < -1.

200.

4. The wide-angle lens as described in any one of claims 1 to 3, characterized in that, When the radius of curvature of the object-side lens surface of the second lens is set to R21 and the radius of curvature of the image-side lens surface of the second lens is set to R22, the following relationship is satisfied: 0.890<(R21+R22) / (R21-R22)<1.

500.

5. The wide-angle lens as described in claim 4, characterized in that, 1.000<(R21+R22) / (R21-R22)<1.

400.

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

Images