Wide-angle lens

Abstract

A wide-angle lens which easily corrects various aberrations and realizes miniaturization. The wide-angle lens of the present invention is composed of a first lens, a second lens, a third lens, a fourth lens, an aperture, a fifth lens, a sixth lens, and a seventh lens which are arranged in this order from the object side, the sixth lens and the seventh lens constitute a cemented lens, the first lens and the second lens are each a negative lens with a concave surface facing the image side, the third lens and the fourth lens are each a positive lens with a convex surface facing the image side, the fifth lens is a positive lens with a convex surface facing the object side and a convex surface facing the image side, the sixth lens is a negative lens with a concave surface facing the image side, the seventh lens is a positive lens with a convex surface facing the object side and a convex surface facing the image side, and when the combined focal length of the first lens, the second lens, the third lens, and the fourth lens is set as f1234 and the combined focal length of the fifth lens, the sixth lens, and the seventh lens is set as f567, the following relationship is satisfied: 0.800 < f1234 / f567 < 3.000.

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 the vehicle-mounted camera equipped with the aforementioned wide-angle lens. In such cases, it is necessary to miniaturize the aforementioned wide-angle lens. However, when miniaturizing the aforementioned wide-angle lens, it is easy to make it difficult to correct various aberrations. 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 easily correct various aberrations and can be easily miniaturized.

[0006] To achieve the above objectives, the present invention provides a wide-angle lens comprising, sequentially arranged from the object side, a first lens, a second lens, a third lens, a fourth lens, an aperture, a fifth lens, a sixth lens, and a seventh lens. The sixth lens and the seventh lens constitute a combined lens. The first lens is a negative lens with its concave surface facing the image side, the second lens is a negative lens with its concave surface facing the image side, the third lens is a positive lens with its convex surface facing the image side, the fourth lens is a positive lens with its convex surface facing the image side, the fifth lens is a positive lens with its convex surface facing both the object side and the image side, the sixth lens is a negative lens with its concave surface facing the image side, and the seventh lens is a positive lens with its convex surface facing both the object side and the image side. When the combined focal distance of the first lens, the second lens, the third lens, and the fourth lens is set to f1234, and the combined focal distance of the fifth lens, the sixth lens, and the seventh lens is set to f567, the following relationship is satisfied: 0.800 < f1234 / f567 < 3.000.

[0007] According to the wide-angle lens of the present invention, when the combined focal distance of the first, second, third, and fourth lenses is set to f1234 and the combined focal distance of the fifth, sixth, and seventh lenses is set to f567, the relationship f1234 / f567 > 0.800 is satisfied. Therefore, excessive optical power of the front lens group composed of the first, second, third, and fourth lenses can be avoided, thereby making it easier to appropriately correct various aberrations and achieve excellent optical characteristics. Furthermore, when the combined focal distance of the first, second, third, and fourth lenses is set to f1234 and the combined focal distance of the fifth, sixth, and seventh lenses is set to f567, the relationship f1234 / f567 < 3.000 is satisfied. Therefore, excessive optical power of the front lens group composed of the first, second, third, and fourth lenses can be avoided, thereby reducing the diameter of each lens in the front lens group and easily achieving miniaturization of the wide-angle lens as a whole.

[0008] Furthermore, in the wide-angle lens of the present invention, it is preferable that the following relationship is satisfied when the focal distance of the entire wide-angle lens is set to f: 2.500 < f1234 / f < 8.000.

[0009] According to the wide-angle lens of the present invention, when the focal distance of the entire wide-angle lens is set to f, the relationship f1234 / f > 2.500 is satisfied. Therefore, it is easier to avoid excessive optical power of the front lens group composed of the first lens, the second lens, the third lens and the fourth lens. As a result, it is easier to properly correct various aberrations and thus easier to achieve excellent optical characteristics. Furthermore, when the focal distance of the entire wide-angle lens is set to f, the relationship f1234 / f < 8.000 is satisfied. Therefore, it is easier to avoid excessive optical power of the front lens group composed of the first lens, the second lens, the third lens and the fourth lens. As a result, the diameter of each lens in the front lens group can be reduced, thereby achieving miniaturization of the entire wide-angle lens.

[0010] Furthermore, in the wide-angle lens of the present invention, it is preferable that the following relationship is satisfied when the focal distance of the entire wide-angle lens is set to f: 2.800 < f567 / f < 3.850.

[0011] According to the wide-angle lens of the present invention, when the focal distance of the entire wide-angle lens is set to f, the relationship f567 / f > 2.800 is satisfied. Therefore, excessive optical power of the rear lens group composed of the fifth, sixth and seventh lenses can be avoided. As a result, various aberrations, especially chromatic aberration, can be easily corrected appropriately, thereby easily achieving excellent optical characteristics. Furthermore, when the focal distance of the entire wide-angle lens is set to f, the relationship f567 / f < 3.850 is satisfied. Therefore, the diameter of each lens and the distance between the object and the image can be reduced, thereby further miniaturizing the entire wide-angle lens.

[0012] Furthermore, in the wide-angle lens of the present invention, it is preferable that when the combined focal distance between 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, the relationship -1.500 < f12 / f < -1.000 is satisfied, and more preferably the relationship -1.500 < f12 / f < -1.200 is satisfied.

[0013] According to the wide-angle lens of the present invention, 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, the relationship f12 / f > -1.500 is satisfied. Therefore, it can ensure that the negative optical power of the first lens and the second lens is large, thereby easily achieving a large viewing angle. Furthermore, 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, the relationship f12 / f < -1.000 is satisfied. Therefore, aberrations can be well corrected.

[0014] Furthermore, in the wide-angle lens of the present invention, it is preferable that when the combined focal distance of the third lens and the fourth lens is set to f34 and the focal distance of the entire wide-angle lens is set to f, the relationship 2.500 < f34 / f < 5.500 is satisfied, and more preferably the relationship 3.000 < f34 / f < 4.500 is satisfied.

[0015] According to the wide-angle lens of the present invention, when the combined focal distance of the third and fourth lenses is set to f34 and the focal distance of the wide-angle lens as a whole is set to f, the relationship f34 / f > 2.500 is satisfied. Therefore, the positive optical focal length of the third and fourth lenses can be avoided, thereby making it easier to appropriately correct various aberrations such as field curvature, chromatic aberration, and coma, and thus making it easier to achieve excellent optical characteristics. Furthermore, when the combined focal distance of the third and fourth lenses is set to f34 and the focal distance of the wide-angle lens as a whole is set to f, the relationship f34 / f < 5.500 is satisfied. Therefore, the diameter of the third and fourth lenses and the distance between the object and the image can be reduced, thereby making the wide-angle lens as a whole more miniaturized.

[0016] Furthermore, in the wide-angle lens of the present invention, it is preferable that when the focal distance of the third lens is set to f3 and the focal distance of the entire wide-angle lens is set to f, the following relationship is satisfied: 5.000 < f3 / f < 10.000.

[0017] According to the wide-angle lens of the present invention, when the focal distance of the third lens is set to f3 and the focal distance of the wide-angle lens as a whole is set to f, the relationship f3 / f > 5.000 is satisfied. Therefore, the positive focal length of the third lens can be avoided, thereby making it easier to appropriately correct various aberrations such as field curvature, magnification chromatic aberration, and coma, and thus making it easier to achieve excellent optical characteristics. Furthermore, when the focal distance of the third lens is set to f3 and the focal distance of the wide-angle lens as a whole is set to f, the relationship f3 / f < 10.000 is satisfied. Therefore, the diameter of the third lens and the distance between the object and the image can be reduced, thereby making the wide-angle lens as a whole more miniaturized.

[0018] Furthermore, in the wide-angle lens of the present invention, it is preferable that when the object-image distance of the wide-angle lens is set as d and the focal distance of the entire wide-angle lens is set as f, the following relationship is satisfied: 11.000 < d / f < 15.000.

[0019] The wide-angle lens according to the present invention satisfies the relationship d / f > 11.000, thus making it easy to appropriately correct various aberrations and thereby easily obtain excellent optical characteristics; on the other hand, it satisfies the relationship d / f < 15.000, thus preventing the overall length of the lens system from becoming too long while suppressing the lens system from becoming too large.

[0020] (Invention Effects)

[0021] According to the present invention, when the combined focal distance of the first, second, third, and fourth lenses is set to f1234 and the combined focal distance of the fifth, sixth, and seventh lenses is set to f567, the relationship f1234 / f567 > 0.800 is satisfied. Therefore, excessive optical power of the front lens group composed of the first, second, third, and fourth lenses can be avoided, thereby making it easier to appropriately correct various aberrations and achieve excellent optical characteristics. Furthermore, when the combined focal distance of the first, second, third, and fourth lenses is set to f1234 and the combined focal distance of the fifth, sixth, and seventh lenses is set to f567, the relationship f1234 / f567 < 3.000 is satisfied. Therefore, excessive optical power of the front lens group composed of the first, second, third, and fourth lenses can be avoided, thereby reducing the diameter of each lens in the front lens group and making it easier to miniaturize the entire wide-angle lens. Attached Figure Description

[0022] Figure 1 This is an explanatory diagram showing the wide-angle lens according to Embodiment 1 of the present invention.

[0023] 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.

[0024] 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.

[0025] 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.

[0026] 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.

[0027] 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.

[0028] Figure 5 This is an explanatory diagram showing the wide-angle lens according to Embodiment 2 of the present invention.

[0029] 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.

[0030] 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.

[0031] 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.

[0032] 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.

[0033] 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.

[0034] Figure 9 This is an explanatory diagram showing the wide-angle lens of Embodiment 3 of the present invention.

[0035] 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.

[0036] 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.

[0037] 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.

[0038] 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.

[0039] 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.

[0040] Figure 13 This is an explanatory diagram showing the wide-angle lens of Embodiment 4 of the present invention.

[0041] 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.

[0042] 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.

[0043] 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.

[0044] 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.

[0045] 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.

[0046] Figure 17 This is an explanatory diagram showing the wide-angle lens of Embodiment 5 of the present invention.

[0047] 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.

[0048] 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.

[0049] 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.

[0050] 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.

[0051] 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.

[0052] Figure 21 This is an explanatory diagram showing the wide-angle lens according to Embodiment 6 of the present invention.

[0053] 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.

[0054] 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.

[0055] 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.

[0056] 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.

[0057] 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.

[0058] Figure 25 This is an explanatory diagram showing the wide-angle lens of Embodiment 7 of the present invention.

[0059] 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.

[0060] 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.

[0061] 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.

[0062] 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.

[0063] 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.

[0064] (Symbol Explanation)

[0065] 1000 wide-angle lens

[0066] 110 First Lens

[0067] 120 Second Lens

[0068] 130 Third Lens

[0069] 140 Fourth Lens

[0070] 150 Fifth Lens

[0071] 160 Sixth Lens

[0072] 170 Seventh Lens

[0073] 180 aperture

[0074] 190 light-blocking sheet

[0075] 200 filters

[0076] 300 camera elements Detailed Implementation

[0077] 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.

[0078] (Implementation Method 1)

[0079] 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.

[0080] like Figure 1 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.

[0081] 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.

[0082] 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.

[0083] 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.

[0084] 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.

[0085] 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.

[0086] 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.

[0087] 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.

[0088] 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.

[0089] 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.

[0090] 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.

[0091] (Table 1)

[0092]

[0093] In Table 1 above, the units for radius of curvature, thickness, and focal distance are mm, Nd is the refractive index of light at 587.56 nanometers, νd is the Abbe number, and * indicates an aspherical surface.

[0094] (Table 2-1)

[0095]

[0096] (Table 2-2)

[0097] 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

[0098] 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.

[0099] 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.

[0100] [Mathematical Expression 1]

[0101]

[0102] Here, in the wide-angle lens 1000, the combined focal distance of the first lens 110, the second lens 120, the third lens 130, and the fourth lens 140 is 3.148 mm, and the combined focal distance of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.740 mm. Therefore, the following condition 1 is satisfied:

[0103] 0.800 < f1234 / f567 < 3.000

[0104] In condition 1, if f1234 / f567 is below 0.800, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too strong, making it difficult to properly correct various aberrations. On the other hand, if f1234 / f567 is above 3.000, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too weak, making it difficult to reduce the diameter of each lens in the front lens group and to achieve overall miniaturization of the wide-angle lens.

[0105] In contrast, in this embodiment, since condition 1 is satisfied, it has the advantages of being able to easily correct various aberrations and being easy to miniaturize.

[0106] Furthermore, in the wide-angle lens 1000, the combined focal distance of the first lens 110, the second lens 120, the third lens 130, and the fourth lens 140 is 3.148 mm, and the overall focal distance f of the lens system is 1.023 mm. Therefore, the following condition 2 is satisfied:

[0107] 2.500 < f1234 / f < 8.000

[0108] In condition 2, if f1234 / f is below 2.500, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too strong, making it difficult to properly correct various aberrations. On the other hand, if f1234 / f is above 8.000, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too weak, making it difficult to reduce the diameter of each lens in the front lens group and making it difficult to achieve overall miniaturization of the wide-angle lens.

[0109] In contrast, in this embodiment, since condition 2 is satisfied, it has the advantages of making it easier to properly correct various aberrations and making it easier to achieve miniaturization.

[0110] Furthermore, in the wide-angle lens 1000, the combined focal distance of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.740 mm, and the overall focal distance f of the lens system is 1.023 mm. Therefore, the following condition 3 is satisfied:

[0111] 2.800 < f567 / f < 3.850

[0112] In condition 3, if f567 / f is below 2.800, the optical focal length of the rear lens group consisting of the fifth, sixth, and seventh lenses will be too strong, making it difficult to properly correct various aberrations, especially chromatic aberration. On the other hand, if f567 / f is above 3.850, it will be difficult to reduce the diameter of each lens and the distance between the object and the image, making it difficult to achieve overall miniaturization of the wide-angle lens.

[0113] In contrast, in this embodiment, since condition 3 is satisfied, it has the advantages of being able to easily correct various aberrations, especially chromatic aberrations, and being easier to miniaturize.

[0114] Furthermore, in the wide-angle lens 1000, the combined focal distance of the first lens 110 and the second lens 120 is -1.338mm, and the overall focal distance f of the lens system is 1.023mm. Therefore, the following condition 4 is satisfied:

[0115] -1.500 < f12 / f < -1.000

[0116] In condition 4, if f12 / f is below -1.500, the negative optical power of the first and second lenses is small, making it difficult to achieve a large angle of view. On the other hand, if f12 / f is above -1.000, it is not easy to correct aberrations.

[0117] In contrast, in this embodiment, since condition 4 is satisfied, it has the advantages of easily achieving a large viewing angle and more easily correcting aberrations.

[0118] Furthermore, in the wide-angle lens 1000, the combined focal distance of the third lens 130 and the fourth lens 140 is 3.122 mm, and the overall focal distance f of the lens system is 1.023 mm. Therefore, the following condition 5 is satisfied:

[0119] 2.500 < f34 / f < 5.500

[0120] In condition 5, if f34 / f is below 2.500, the positive optical focal length of the third and fourth lenses is too large, making it difficult to properly correct various aberrations such as field curvature, magnification chromatic aberration, and coma. On the other hand, if f34 / f is above 5.500, it is not easy to reduce the diameter of the third and fourth lenses and the distance between the object and the image, making it difficult to achieve overall miniaturization of the wide-angle lens.

[0121] In contrast, in this embodiment, since condition 5 is satisfied, it has the advantages of easily and appropriately correcting various aberrations such as field curvature, magnification chromatic aberration, and coma, and it is easier to achieve overall miniaturization of the wide-angle lens.

[0122] Furthermore, in the wide-angle lens 1000, the focal distance of the third lens 130 is 6.742 mm, and the focal distance f of the entire lens system is 1.023 mm. Therefore, the following condition 6 is satisfied:

[0123] 5.000 < f3 / f < 10.000

[0124] In condition 6, if f3 / f is less than 5.000, the positive optical focal length of the third lens is too large, making it difficult to properly correct various aberrations such as field curvature, magnification chromatic aberration, and coma. On the other hand, if f3 / f is greater than 10.000, it is not easy to reduce the diameter of the third lens and the distance between the object and the image, making it difficult to achieve overall miniaturization of the wide-angle lens.

[0125] In contrast, in this embodiment, since condition 6 is satisfied, it has the advantages of easily and appropriately correcting various aberrations such as field curvature, magnification chromatic aberration, and coma, and it is easier to achieve overall miniaturization of the wide-angle lens.

[0126] Furthermore, in the wide-angle lens 1000, the object-image distance d is 13.611 mm, and the overall focal distance f of the lens system is 1.023 mm. Therefore, the following condition 7 is satisfied:

[0127] 11.000 < d / f < 15.000

[0128] In condition 7, if d / f is below 11.000, it is not easy to properly correct various aberrations. On the other hand, if d / f is above 15.000, the overall length of the lens system becomes too long.

[0129] In contrast, in this embodiment, since condition 7 is satisfied, it is easy to properly correct various aberrations, easily obtain excellent optical characteristics, and suppress the lens system from becoming too large while avoiding the overall length of the lens system becoming too long.

[0130] 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, and it is easy to achieve the miniaturization of the wide-angle lens as a whole.

[0131] (Implementation Method 2)

[0132] 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 7AThis 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.

[0133] like Figure 5 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.

[0134] 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.

[0135] 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.

[0136] 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.

[0137] 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.

[0138] (Table 3)

[0139]

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

[0141] (Table 4-1)

[0142]

[0143] (Table 4-2)

[0144] noodle A8 A10 A12 A14 A16 3 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 4 1.18832E-02 -3.21383E-03 7.23623E-04 0.00000E+00 0.00000E+00 5 -7.11892E-03 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 6 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 7 1.48329E-02 -9.20347E-04 0.00000E+00 0.00000E+00 0.00000E+00 8 3.16264E-03 4.17741E-03 0.00000E+00 0.00000E+00 0.00000E+00 12 -7.44565E-04 -1.42901E-03 0.00000E+00 0.00000E+00 0.00000E+00 13 1.80337E-01 -4.80759E-02 4.57265E-03 0.00000E+00 0.00000E+00 14 1.50208E-02 -4.69107E-03 5.90742E-04 0.00000E+00 0.00000E+00

[0145] In Tables 4-1 and 4-2 above, when the lens surface is a convex surface protruding 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.

[0146] 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.

[0147] Here, in the wide-angle lens 1000, the combined focal distance of the first lens 110, the second lens 120, the third lens 130, and the fourth lens 140 is 4.237 mm, and the combined focal distance of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.640 mm. Therefore, the following condition 1 is satisfied:

[0148] 0.800 < f1234 / f567 < 3.000

[0149] In condition 1, if f1234 / f567 is below 0.800, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too strong, making it difficult to properly correct various aberrations. On the other hand, if f1234 / f567 is above 3.000, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too weak, making it difficult to reduce the diameter of each lens in the front lens group and to achieve overall miniaturization of the wide-angle lens.

[0150] In contrast, in this embodiment, since condition 1 is satisfied, it has the advantages of being able to easily correct various aberrations and being easy to miniaturize.

[0151] Furthermore, in the wide-angle lens 1000, the combined focal distance of the first lens 110, the second lens 120, the third lens 130, and the fourth lens 140 is 4.237 mm, and the overall focal distance f of the lens system is 1.062 mm. Therefore, the following condition 2 is satisfied:

[0152] 2.500 < f1234 / f < 8.000

[0153] In condition 2, if f1234 / f is below 2.500, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too strong, making it difficult to properly correct various aberrations. On the other hand, if f1234 / f is above 8.000, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too weak, making it difficult to reduce the diameter of each lens in the front lens group and making it difficult to achieve overall miniaturization of the wide-angle lens.

[0154] In contrast, in this embodiment, since condition 2 is satisfied, it has the advantages of making it easier to properly correct various aberrations and making it easier to achieve miniaturization.

[0155] Furthermore, in the wide-angle lens 1000, the combined focal distance of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 8.893 mm, and the overall focal distance f of the lens system is 1.062 mm. Therefore, the following condition 3 is satisfied:

[0156] 2.800 < f567 / f < 3.850

[0157] In condition 3, if f567 / f is below 2.800, the optical focal length of the rear lens group consisting of the fifth, sixth, and seventh lenses will be too strong, making it difficult to properly correct various aberrations, especially chromatic aberration. On the other hand, if f567 / f is above 3.850, it will be difficult to reduce the diameter of each lens and the distance between the object and the image, making it difficult to achieve overall miniaturization of the wide-angle lens.

[0158] In contrast, in this embodiment, since condition 3 is satisfied, it has the advantages of being able to easily correct various aberrations, especially chromatic aberrations, and being easier to miniaturize.

[0159] Furthermore, in the wide-angle lens 1000, the combined focal distance of the first lens 110 and the second lens 120 is -1.406mm, and the overall focal distance f of the lens system is 1.062mm. Therefore, the following condition 4 is satisfied:

[0160] -1.500 < f12 / f < -1.000

[0161] In condition 4, if f12 / f is below -1.500, the negative optical power of the first and second lenses is small, making it difficult to achieve a large angle of view. On the other hand, if f12 / f is above -1.000, it is not easy to correct aberrations.

[0162] In contrast, in this embodiment, since condition 4 is satisfied, it has the advantages of easily achieving a large viewing angle and more easily correcting aberrations.

[0163] Furthermore, in the wide-angle lens 1000, the combined focal distance of the third lens 130 and the fourth lens 140 is 3.380 mm, and the overall focal distance f of the lens system is 1.062 mm. Therefore, the following condition 5 is satisfied:

[0164] 2.500 < f34 / f < 5.500

[0165] In condition 5, if f34 / f is below 2.500, the positive optical focal length of the third and fourth lenses is too large, making it difficult to properly correct various aberrations such as field curvature, magnification chromatic aberration, and coma. On the other hand, if f34 / f is above 5.500, it is not easy to reduce the diameter of the third and fourth lenses and the distance between the object and the image, making it difficult to achieve overall miniaturization of the wide-angle lens.

[0166] In contrast, in this embodiment, since condition 5 is satisfied, it has the advantages of easily and appropriately correcting various aberrations such as field curvature, magnification chromatic aberration, and coma, and it is easier to achieve overall miniaturization of the wide-angle lens.

[0167] Furthermore, in the wide-angle lens 1000, the focal distance of the third lens 130 is 6.297 mm, and the focal distance f of the entire lens system is 1.062 mm. Therefore, the following condition 6 is satisfied:

[0168] 5.000 < f3 / f < 10.000

[0169] In condition 6, if f3 / f is less than 5.000, the positive optical focal length of the third lens is too large, making it difficult to properly correct various aberrations such as field curvature, magnification chromatic aberration, and coma. On the other hand, if f3 / f is greater than 10.000, it is not easy to reduce the diameter of the third lens and the distance between the object and the image, making it difficult to achieve overall miniaturization of the wide-angle lens.

[0170] In contrast, in this embodiment, since condition 6 is satisfied, it has the advantages of easily and appropriately correcting various aberrations such as field curvature, magnification chromatic aberration, and coma, and it is easier to achieve overall miniaturization of the wide-angle lens.

[0171] Furthermore, in the wide-angle lens 1000, the object-image distance d is 13.610 mm, and the overall focal distance f of the lens system is 1.062 mm. Therefore, the following condition 7 is satisfied:

[0172] 11.000 < d / f < 15.000

[0173] In condition 7, if d / f is below 11.000, it is not easy to properly correct various aberrations. On the other hand, if d / f is above 15.000, the overall length of the lens system becomes too long.

[0174] In contrast, in this embodiment, since condition 7 is satisfied, it is easy to properly correct various aberrations, easily obtain excellent optical characteristics, and suppress the lens system from becoming too large while avoiding the overall length of the lens system becoming too long.

[0175] 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, and it is easy to achieve the miniaturization of the wide-angle lens as a whole.

[0176] (Implementation Method 3)

[0177] 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.

[0178] like Figure 9As 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.

[0179] 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.

[0180] 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.

[0181] 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.

[0182] 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.

[0183] (Table 5)

[0184]

[0185] In Table 5 above, the units for radius of curvature, thickness, and focal distance are mm, Nd is the refractive index of light at 587.56 nanometers, νd is the Abbe number, and * indicates an aspherical surface.

[0186] (Table 6-1)

[0187]

[0188] (Table 6-2)

[0189] 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

[0190] 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.

[0191] 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.

[0192] Here, in the wide-angle lens 1000, the combined focal distance of the first lens 110, the second lens 120, the third lens 130, and the fourth lens 140 is 3.572 mm, and the combined focal distance of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.663 mm. Therefore, the following condition 1 is satisfied:

[0193] 0.800 < f1234 / f567 < 3.000

[0194] In condition 1, if f1234 / f567 is below 0.800, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too strong, making it difficult to properly correct various aberrations. On the other hand, if f1234 / f567 is above 3.000, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too weak, making it difficult to reduce the diameter of each lens in the front lens group and to achieve overall miniaturization of the wide-angle lens.

[0195] In contrast, in this embodiment, since condition 1 is satisfied, it has the advantages of being able to easily correct various aberrations and being easy to miniaturize.

[0196] Furthermore, in the wide-angle lens 1000, the combined focal distance of the first lens 110, the second lens 120, the third lens 130, and the fourth lens 140 is 3.572 mm, and the overall focal distance f of the lens system is 1.026 mm. Therefore, the following condition 2 is satisfied:

[0197] 2.500 < f1234 / f < 8.000

[0198] In condition 2, if f1234 / f is below 2.500, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too strong, making it difficult to properly correct various aberrations. On the other hand, if f1234 / f is above 8.000, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too weak, making it difficult to reduce the diameter of each lens in the front lens group and making it difficult to achieve overall miniaturization of the wide-angle lens.

[0199] In contrast, in this embodiment, since condition 2 is satisfied, it has the advantages of making it easier to properly correct various aberrations and making it easier to achieve miniaturization.

[0200] Furthermore, in the wide-angle lens 1000, the combined focal distance of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.663 mm, and the overall focal distance f of the lens system is 1.026 mm. Therefore, the following condition 3 is satisfied:

[0201] 2.800 < f567 / f < 3.850

[0202] In condition 3, if f567 / f is below 2.800, the optical focal length of the rear lens group consisting of the fifth, sixth, and seventh lenses will be too strong, making it difficult to properly correct various aberrations, especially chromatic aberration. On the other hand, if f567 / f is above 3.850, it will be difficult to reduce the diameter of each lens and the distance between the object and the image, making it difficult to achieve overall miniaturization of the wide-angle lens.

[0203] In contrast, in this embodiment, since condition 3 is satisfied, it has the advantages of being able to easily correct various aberrations, especially chromatic aberrations, and being easier to miniaturize.

[0204] Furthermore, in the wide-angle lens 1000, the combined focal distance of the first lens 110 and the second lens 120 is -1.467mm, and the overall focal distance f of the lens system is 1.026mm. Therefore, the following condition 4 is satisfied:

[0205] -1.500 < f12 / f < -1.000

[0206] In condition 4, if f12 / f is below -1.500, the negative optical power of the first and second lenses is small, making it difficult to achieve a large angle of view. On the other hand, if f12 / f is above -1.000, it is not easy to correct aberrations.

[0207] In contrast, in this embodiment, since condition 4 is satisfied, it has the advantages of easily achieving a large viewing angle and more easily correcting aberrations.

[0208] Furthermore, in the wide-angle lens 1000, the combined focal distance of the third lens 130 and the fourth lens 140 is 3.456 mm, and the overall focal distance f of the lens system is 1.026 mm. Therefore, the following condition 5 is satisfied:

[0209] 2.500 < f34 / f < 5.500

[0210] In condition 5, if f34 / f is below 2.500, the positive optical focal length of the third and fourth lenses is too large, making it difficult to properly correct various aberrations such as field curvature, magnification chromatic aberration, and coma. On the other hand, if f34 / f is above 5.500, it is not easy to reduce the diameter of the third and fourth lenses and the distance between the object and the image, making it difficult to achieve overall miniaturization of the wide-angle lens.

[0211] In contrast, in this embodiment, since condition 5 is satisfied, it has the advantages of easily and appropriately correcting various aberrations such as field curvature, magnification chromatic aberration, and coma, and it is easier to achieve overall miniaturization of the wide-angle lens.

[0212] Furthermore, in the wide-angle lens 1000, the focal distance of the third lens 130 is 7.039 mm, and the focal distance f of the entire lens system is 1.026 mm. Therefore, the following condition 6 is satisfied:

[0213] 5.000 < f3 / f < 10.000

[0214] In condition 6, if f3 / f is less than 5.000, the positive optical focal length of the third lens is too large, making it difficult to properly correct various aberrations such as field curvature, magnification chromatic aberration, and coma. On the other hand, if f3 / f is greater than 10.000, it is not easy to reduce the diameter of the third lens and the distance between the object and the image, making it difficult to achieve overall miniaturization of the wide-angle lens.

[0215] In contrast, in this embodiment, since condition 6 is satisfied, it has the advantages of easily and appropriately correcting various aberrations such as field curvature, magnification chromatic aberration, and coma, and it is easier to achieve overall miniaturization of the wide-angle lens.

[0216] Furthermore, in the wide-angle lens 1000, the object-image distance d is 13.403 mm, and the overall focal distance f of the lens system is 1.026 mm. Therefore, the following condition 7 is satisfied:

[0217] 11.000 < d / f < 15.000

[0218] In condition 7, if d / f is below 11.000, it is not easy to properly correct various aberrations. On the other hand, if d / f is above 15.000, the overall length of the lens system becomes too long.

[0219] In contrast, in this embodiment, since condition 7 is satisfied, it is easy to properly correct various aberrations, easily obtain excellent optical characteristics, and suppress the lens system from becoming too large while avoiding the overall length of the lens system becoming too long.

[0220] 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, and it is easy to achieve the miniaturization of the wide-angle lens as a whole.

[0221] (Implementation Method 4)

[0222] 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.

[0223] like Figure 13 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.

[0224] 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.

[0225] 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.

[0226] 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.

[0227] 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.

[0228] (Table 7)

[0229]

[0230] In Table 7 above, the units for radius of curvature, thickness, and focal distance are mm, Nd is the refractive index of light at 587.56 nanometers, νd is the Abbe number, and * indicates an aspherical surface.

[0231] (Table 8-1)

[0232]

[0233] (Table 8-2)

[0234] 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

[0235] 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.

[0236] 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.

[0237] Here, in the wide-angle lens 1000, the combined focal distance of the first lens 110, the second lens 120, the third lens 130, and the fourth lens 140 is 6.571 mm, and the combined focal distance of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.355 mm. Therefore, the following condition 1 is satisfied:

[0238] 0.800 < f1234 / f567 < 3.000

[0239] In condition 1, if f1234 / f567 is below 0.800, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too strong, making it difficult to properly correct various aberrations. On the other hand, if f1234 / f567 is above 3.000, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too weak, making it difficult to reduce the diameter of each lens in the front lens group and to achieve overall miniaturization of the wide-angle lens.

[0240] In contrast, in this embodiment, since condition 1 is satisfied, it has the advantages of being able to easily correct various aberrations and being easy to miniaturize.

[0241] Furthermore, in the wide-angle lens 1000, the combined focal distance of the first lens 110, the second lens 120, the third lens 130, and the fourth lens 140 is 6.571 mm, and the overall focal distance f of the lens system is 1.011 mm. Therefore, the following condition 2 is satisfied:

[0242] 2.500 < f1234 / f < 8.000

[0243] In condition 2, if f1234 / f is below 2.500, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too strong, making it difficult to properly correct various aberrations. On the other hand, if f1234 / f is above 8.000, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too weak, making it difficult to reduce the diameter of each lens in the front lens group and making it difficult to achieve overall miniaturization of the wide-angle lens.

[0244] In contrast, in this embodiment, since condition 2 is satisfied, it has the advantages of making it easier to properly correct various aberrations and making it easier to achieve miniaturization.

[0245] Furthermore, in the wide-angle lens 1000, the combined focal distance of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.355 mm, and the overall focal distance f of the lens system is 1.011 mm. Therefore, the following condition 3 is satisfied:

[0246] 2.800 < f567 / f < 3.850

[0247] In condition 3, if f567 / f is below 2.800, the optical focal length of the rear lens group consisting of the fifth, sixth, and seventh lenses will be too strong, making it difficult to properly correct various aberrations, especially chromatic aberration. On the other hand, if f567 / f is above 3.850, it will be difficult to reduce the diameter of each lens and the distance between the object and the image, making it difficult to achieve overall miniaturization of the wide-angle lens.

[0248] In contrast, in this embodiment, since condition 3 is satisfied, it has the advantages of being able to easily correct various aberrations, especially chromatic aberrations, and being easier to miniaturize.

[0249] Furthermore, in the wide-angle lens 1000, the combined focal distance of the first lens 110 and the second lens 120 is -1.347 mm, and the overall focal distance f of the lens system is 1.011 mm. Therefore, the following condition 4 is satisfied:

[0250] -1.500 < f12 / f < -1.000

[0251] In condition 4, if f12 / f is below -1.500, the negative optical power of the first and second lenses is small, making it difficult to achieve a large angle of view. On the other hand, if f12 / f is above -1.000, it is not easy to correct aberrations.

[0252] In contrast, in this embodiment, since condition 4 is satisfied, it has the advantages of easily achieving a large viewing angle and more easily correcting aberrations.

[0253] Furthermore, in the wide-angle lens 1000, the combined focal distance of the third lens 130 and the fourth lens 140 is 3.614 mm, and the overall focal distance f of the lens system is 1.011 mm. Therefore, the following condition 5 is satisfied:

[0254] 2.500 < f34 / f < 5.500

[0255] In condition 5, if f34 / f is below 2.500, the positive optical focal length of the third and fourth lenses is too large, making it difficult to properly correct various aberrations such as field curvature, magnification chromatic aberration, and coma. On the other hand, if f34 / f is above 5.500, it is not easy to reduce the diameter of the third and fourth lenses and the distance between the object and the image, making it difficult to achieve overall miniaturization of the wide-angle lens.

[0256] In contrast, in this embodiment, since condition 5 is satisfied, it has the advantages of easily and appropriately correcting various aberrations such as field curvature, magnification chromatic aberration, and coma, and it is easier to achieve overall miniaturization of the wide-angle lens.

[0257] Furthermore, in the wide-angle lens 1000, the focal distance of the third lens 130 is 7.736 mm, and the focal distance f of the entire lens system is 1.011 mm. Therefore, the following condition 6 is satisfied:

[0258] 5.000 < f3 / f < 10.000

[0259] In condition 6, if f3 / f is less than 5.000, the positive optical focal length of the third lens is too large, making it difficult to properly correct various aberrations such as field curvature, magnification chromatic aberration, and coma. On the other hand, if f3 / f is greater than 10.000, it is not easy to reduce the diameter of the third lens and the distance between the object and the image, making it difficult to achieve overall miniaturization of the wide-angle lens.

[0260] In contrast, in this embodiment, since condition 6 is satisfied, it has the advantages of easily and appropriately correcting various aberrations such as field curvature, magnification chromatic aberration, and coma, and it is easier to achieve overall miniaturization of the wide-angle lens.

[0261] Furthermore, in the wide-angle lens 1000, the object-image distance d is 13.404 mm, and the overall focal distance f of the lens system is 1.011 mm. Therefore, the following condition 7 is satisfied:

[0262] 11.000 < d / f < 15.000

[0263] In condition 7, if d / f is below 11.000, it is not easy to properly correct various aberrations. On the other hand, if d / f is above 15.000, the overall length of the lens system becomes too long.

[0264] In contrast, in this embodiment, since condition 7 is satisfied, it is easy to properly correct various aberrations, easily obtain excellent optical characteristics, and suppress the lens system from becoming too large while avoiding the overall length of the lens system becoming too long.

[0265] 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, and it is easy to achieve the miniaturization of the wide-angle lens as a whole.

[0266] (Implementation Method 5)

[0267] 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 20L This 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.

[0268] like Figure 17 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.

[0269] 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.

[0270] 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.

[0271] 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.

[0272] 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.

[0273] (Table 9)

[0274]

[0275] In Table 9 above, the units for radius of curvature, thickness, and focal distance are mm, Nd is the refractive index of light at 587.56 nanometers, νd is the Abbe number, and * indicates an aspherical surface.

[0276] (Table 10-1)

[0277]

[0278] (Table 10-2)

[0279] 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

[0280] 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.

[0281] 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.

[0282] Here, in the wide-angle lens 1000, the combined focal distance of the first lens 110, the second lens 120, the third lens 130, and the fourth lens 140 is 4.142 mm, and the combined focal distance of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.679 mm. Therefore, the following condition 1 is satisfied:

[0283] 0.800 < f1234 / f567 < 3.000

[0284] In condition 1, if f1234 / f567 is below 0.800, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too strong, making it difficult to properly correct various aberrations. On the other hand, if f1234 / f567 is above 3.000, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too weak, making it difficult to reduce the diameter of each lens in the front lens group and to achieve overall miniaturization of the wide-angle lens.

[0285] In contrast, in this embodiment, since condition 1 is satisfied, it has the advantages of being able to easily correct various aberrations and being easy to miniaturize.

[0286] Furthermore, in the wide-angle lens 1000, the combined focal distance of the first lens 110, the second lens 120, the third lens 130, and the fourth lens 140 is 4.142 mm, and the overall focal distance f of the lens system is 1.021 mm. Therefore, the following condition 2 is satisfied:

[0287] 2.500 < f1234 / f < 8.000

[0288] In condition 2, if f1234 / f is below 2.500, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too strong, making it difficult to properly correct various aberrations. On the other hand, if f1234 / f is above 8.000, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too weak, making it difficult to reduce the diameter of each lens in the front lens group and making it difficult to achieve overall miniaturization of the wide-angle lens.

[0289] In contrast, in this embodiment, since condition 2 is satisfied, it has the advantages of making it easier to properly correct various aberrations and making it easier to achieve miniaturization.

[0290] Furthermore, in the wide-angle lens 1000, the combined focal distance of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.679 mm, and the overall focal distance f of the lens system is 1.021 mm. Therefore, the following condition 3 is satisfied:

[0291] 2.800 < f567 / f < 3.850

[0292] In condition 3, if f567 / f is below 2.800, the optical focal length of the rear lens group consisting of the fifth, sixth, and seventh lenses will be too strong, making it difficult to properly correct various aberrations, especially chromatic aberration. On the other hand, if f567 / f is above 3.850, it will be difficult to reduce the diameter of each lens and the distance between the object and the image, making it difficult to achieve overall miniaturization of the wide-angle lens.

[0293] In contrast, in this embodiment, since condition 3 is satisfied, it has the advantages of being able to easily correct various aberrations, especially chromatic aberrations, and being easier to miniaturize.

[0294] Furthermore, in the wide-angle lens 1000, the combined focal distance of the first lens 110 and the second lens 120 is -1.258 mm, and the overall focal distance f of the lens system is 1.021 mm. Therefore, the following condition 4 is satisfied:

[0295] -1.500 < f12 / f < -1.000

[0296] In condition 4, if f12 / f is below -1.500, the negative optical power of the first and second lenses is small, making it difficult to achieve a large angle of view. On the other hand, if f12 / f is above -1.000, it is not easy to correct aberrations.

[0297] In contrast, in this embodiment, since condition 4 is satisfied, it has the advantages of easily achieving a large viewing angle and more easily correcting aberrations.

[0298] Furthermore, in the wide-angle lens 1000, the combined focal distance of the third lens 130 and the fourth lens 140 is 3.259 mm, and the overall focal distance f of the lens system is 1.021 mm. Therefore, the following condition 5 is satisfied:

[0299] 2.500 < f34 / f < 5.500

[0300] In condition 5, if f34 / f is below 2.500, the positive optical focal length of the third and fourth lenses is too large, making it difficult to properly correct various aberrations such as field curvature, magnification chromatic aberration, and coma. On the other hand, if f34 / f is above 5.500, it is not easy to reduce the diameter of the third and fourth lenses and the distance between the object and the image, making it difficult to achieve overall miniaturization of the wide-angle lens.

[0301] In contrast, in this embodiment, since condition 5 is satisfied, it has the advantages of easily and appropriately correcting various aberrations such as field curvature, magnification chromatic aberration, and coma, and it is easier to achieve overall miniaturization of the wide-angle lens.

[0302] Furthermore, in the wide-angle lens 1000, the focal distance of the third lens 130 is 7.227 mm, and the focal distance f of the entire lens system is 1.021 mm. Therefore, the following condition 6 is satisfied:

[0303] 5.000 < f3 / f < 10.000

[0304] In condition 6, if f3 / f is less than 5.000, the positive optical focal length of the third lens is too large, making it difficult to properly correct various aberrations such as field curvature, magnification chromatic aberration, and coma. On the other hand, if f3 / f is greater than 10.000, it is not easy to reduce the diameter of the third lens and the distance between the object and the image, making it difficult to achieve overall miniaturization of the wide-angle lens.

[0305] In contrast, in this embodiment, since condition 6 is satisfied, it has the advantages of easily and appropriately correcting various aberrations such as field curvature, magnification chromatic aberration, and coma, and it is easier to achieve overall miniaturization of the wide-angle lens.

[0306] Furthermore, in the wide-angle lens 1000, the object-image distance d is 13.398 mm, and the overall focal distance f of the lens system is 1.021 mm. Therefore, the following condition 7 is satisfied:

[0307] 11.000 < d / f < 15.000

[0308] In condition 7, if d / f is below 11.000, it is not easy to properly correct various aberrations. On the other hand, if d / f is above 15.000, the overall length of the lens system becomes too long.

[0309] In contrast, in this embodiment, since condition 7 is satisfied, it is easy to properly correct various aberrations, easily obtain excellent optical characteristics, and suppress the lens system from becoming too large while avoiding the overall length of the lens system becoming too long.

[0310] 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, and it is easy to achieve the miniaturization of the wide-angle lens as a whole.

[0311] (Implementation Method 6)

[0312] Figure 21 This 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.

[0313] like Figure 21 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.

[0314] 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.

[0315] 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.

[0316] 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.

[0317] 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.

[0318] (Table 11)

[0319]

[0320] In Table 11 above, the units for radius of curvature, thickness, and focal distance are mm, Nd is the refractive index of light at 587.56 nanometers, νd is the Abbe number, and * indicates an aspherical surface.

[0321] (Table 12-1)

[0322]

[0323] (Table 12-2)

[0324] 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

[0325] 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.

[0326] 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.

[0327] Here, in the wide-angle lens 1000, the combined focal distance of the first lens 110, the second lens 120, the third lens 130, and the fourth lens 140 is 4.528 mm, and the combined focal distance of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.546 mm. Therefore, the following condition 1 is satisfied:

[0328] 0.800 < f1234 / f567 < 3.000

[0329] In condition 1, if f1234 / f567 is below 0.800, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too strong, making it difficult to properly correct various aberrations. On the other hand, if f1234 / f567 is above 3.000, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too weak, making it difficult to reduce the diameter of each lens in the front lens group and to achieve overall miniaturization of the wide-angle lens.

[0330] In contrast, in this embodiment, since condition 1 is satisfied, it has the advantages of being able to easily correct various aberrations and being easy to miniaturize.

[0331] Furthermore, in the wide-angle lens 1000, the combined focal distance of the first lens 110, the second lens 120, the third lens 130, and the fourth lens 140 is 4.528 mm, and the overall focal distance f of the lens system is 1.018 mm. Therefore, the following condition 2 is satisfied:

[0332] 2.500 < f1234 / f < 8.000

[0333] In condition 2, if f1234 / f is below 2.500, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too strong, making it difficult to properly correct various aberrations. On the other hand, if f1234 / f is above 8.000, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too weak, making it difficult to reduce the diameter of each lens in the front lens group and making it difficult to achieve overall miniaturization of the wide-angle lens.

[0334] In contrast, in this embodiment, since condition 2 is satisfied, it has the advantages of making it easier to properly correct various aberrations and making it easier to achieve miniaturization.

[0335] Furthermore, in the wide-angle lens 1000, the combined focal distance of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.546 mm, and the overall focal distance f of the lens system is 1.018 mm. Therefore, the following condition 3 is satisfied:

[0336] 2.800 < f567 / f < 3.850

[0337] In condition 3, if f567 / f is below 2.800, the optical focal length of the rear lens group consisting of the fifth, sixth, and seventh lenses will be too strong, making it difficult to properly correct various aberrations, especially chromatic aberration. On the other hand, if f567 / f is above 3.850, it will be difficult to reduce the diameter of each lens and the distance between the object and the image, making it difficult to achieve overall miniaturization of the wide-angle lens.

[0338] In contrast, in this embodiment, since condition 3 is satisfied, it has the advantages of being able to easily correct various aberrations, especially chromatic aberrations, and being easier to miniaturize.

[0339] Furthermore, in the wide-angle lens 1000, the combined focal distance of the first lens 110 and the second lens 120 is -1.310 mm, and the overall focal distance f of the lens system is 1.018 mm. Therefore, the following condition 4 is satisfied:

[0340] -1.500 < f12 / f < -1.000

[0341] In condition 4, if f12 / f is below -1.500, the negative optical power of the first and second lenses is small, making it difficult to achieve a large angle of view. On the other hand, if f12 / f is above -1.000, it is not easy to correct aberrations.

[0342] In contrast, in this embodiment, since condition 4 is satisfied, it has the advantages of easily achieving a large viewing angle and more easily correcting aberrations.

[0343] Furthermore, in the wide-angle lens 1000, the combined focal distance of the third lens 130 and the fourth lens 140 is 3.338 mm, and the overall focal distance f of the lens system is 1.018 mm. Therefore, the following condition 5 is satisfied:

[0344] 2.500 < f34 / f < 5.500

[0345] In condition 5, if f34 / f is below 2.500, the positive optical focal length of the third and fourth lenses is too large, making it difficult to properly correct various aberrations such as field curvature, magnification chromatic aberration, and coma. On the other hand, if f34 / f is above 5.500, it is not easy to reduce the diameter of the third and fourth lenses and the distance between the object and the image, making it difficult to achieve overall miniaturization of the wide-angle lens.

[0346] In contrast, in this embodiment, since condition 5 is satisfied, it has the advantages of easily and appropriately correcting various aberrations such as field curvature, magnification chromatic aberration, and coma, and it is easier to achieve overall miniaturization of the wide-angle lens.

[0347] Furthermore, in the wide-angle lens 1000, the focal distance of the third lens 130 is 9.374 mm, and the focal distance f of the entire lens system is 1.018 mm. Therefore, the following condition 6 is satisfied:

[0348] 5.000 < f3 / f < 10.000

[0349] In condition 6, if f3 / f is less than 5.000, the positive optical focal length of the third lens is too large, making it difficult to properly correct various aberrations such as field curvature, magnification chromatic aberration, and coma. On the other hand, if f3 / f is greater than 10.000, it is not easy to reduce the diameter of the third lens and the distance between the object and the image, making it difficult to achieve overall miniaturization of the wide-angle lens.

[0350] In contrast, in this embodiment, since condition 6 is satisfied, it has the advantages of easily and appropriately correcting various aberrations such as field curvature, magnification chromatic aberration, and coma, and it is easier to achieve overall miniaturization of the wide-angle lens.

[0351] Furthermore, in the wide-angle lens 1000, the object-image distance d is 13.383 mm, and the overall focal distance f of the lens system is 1.018 mm. Therefore, the following condition 7 is satisfied:

[0352] 11.000 < d / f < 15.000

[0353] In condition 7, if d / f is below 11.000, it is not easy to properly correct various aberrations. On the other hand, if d / f is above 15.000, the overall length of the lens system becomes too long.

[0354] In contrast, in this embodiment, since condition 7 is satisfied, it is easy to properly correct various aberrations, easily obtain excellent optical characteristics, and suppress the lens system from becoming too large while avoiding the overall length of the lens system becoming too long.

[0355] 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, and it is easy to achieve the miniaturization of the wide-angle lens as a whole.

[0356] (Implementation Method 7)

[0357] 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.

[0358] like Figure 25As 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.

[0359] 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.

[0360] In addition, such as Figure 25 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.

[0361] 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.

[0362] 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.

[0363] (Table 13)

[0364]

[0365] In Table 11 above, the units for radius of curvature, thickness, and focal distance are mm, Nd is the refractive index of light at 587.56 nanometers, νd is the Abbe number, and * indicates an aspherical surface.

[0366] (Table 14-1)

[0367]

[0368] (Table 14-2)

[0369] 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

[0370] 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.

[0371] 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.

[0372] Here, in the wide-angle lens 1000, the combined focal distance of the first lens 110, the second lens 120, the third lens 130, and the fourth lens 140 is 4.815 mm, and the combined focal distance of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.557 mm. Therefore, the following condition 1 is satisfied:

[0373] 0.800 < f1234 / f567 < 3.000

[0374] In condition 1, if f1234 / f567 is below 0.800, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too strong, making it difficult to properly correct various aberrations. On the other hand, if f1234 / f567 is above 3.000, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too weak, making it difficult to reduce the diameter of each lens in the front lens group and to achieve overall miniaturization of the wide-angle lens.

[0375] In contrast, in this embodiment, since condition 1 is satisfied, it has the advantages of being able to easily correct various aberrations and being easy to miniaturize.

[0376] Furthermore, in the wide-angle lens 1000, the combined focal distance of the first lens 110, the second lens 120, the third lens 130, and the fourth lens 140 is 4.815 mm, and the overall focal distance f of the lens system is 1.019 mm. Therefore, the following condition 2 is satisfied:

[0377] 2.500 < f1234 / f < 8.000

[0378] In condition 2, if f1234 / f is below 2.500, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too strong, making it difficult to properly correct various aberrations. On the other hand, if f1234 / f is above 8.000, the optical focal length of the front lens group consisting of the first lens, the second lens, the third lens, and the fourth lens is too weak, making it difficult to reduce the diameter of each lens in the front lens group and making it difficult to achieve overall miniaturization of the wide-angle lens.

[0379] In contrast, in this embodiment, since condition 2 is satisfied, it has the advantages of making it easier to properly correct various aberrations and making it easier to achieve miniaturization.

[0380] Furthermore, in the wide-angle lens 1000, the combined focal distance of the fifth lens 150, the sixth lens 160, and the seventh lens 170 is 3.557 mm, and the overall focal distance f of the lens system is 1.019 mm. Therefore, the following condition 3 is satisfied:

[0381] 2.800 < f567 / f < 3.850

[0382] In condition 3, if f567 / f is below 2.800, the optical focal length of the rear lens group consisting of the fifth, sixth, and seventh lenses will be too strong, making it difficult to properly correct various aberrations, especially chromatic aberration. On the other hand, if f567 / f is above 3.850, it will be difficult to reduce the diameter of each lens and the distance between the object and the image, making it difficult to achieve overall miniaturization of the wide-angle lens.

[0383] In contrast, in this embodiment, since condition 3 is satisfied, it has the advantages of being able to easily correct various aberrations, especially chromatic aberrations, and being easier to miniaturize.

[0384] Furthermore, in the wide-angle lens 1000, the combined focal distance of the first lens 110 and the second lens 120 is -1.310 mm, and the overall focal distance f of the lens system is 1.019 mm. Therefore, the following condition 4 is satisfied:

[0385] -1.500 < f12 / f < -1.000

[0386] In condition 4, if f12 / f is below -1.500, the negative optical power of the first and second lenses is small, making it difficult to achieve a large angle of view. On the other hand, if f12 / f is above -1.000, it is not easy to correct aberrations.

[0387] In contrast, in this embodiment, since condition 4 is satisfied, it has the advantages of easily achieving a large viewing angle and more easily correcting aberrations.

[0388] Furthermore, in the wide-angle lens 1000, the combined focal distance of the third lens 130 and the fourth lens 140 is 3.394 mm, and the overall focal distance f of the lens system is 1.019 mm. Therefore, the following condition 5 is satisfied:

[0389] 2.500 < f34 / f < 5.500

[0390] In condition 5, if f34 / f is below 2.500, the positive optical focal length of the third and fourth lenses is too large, making it difficult to properly correct various aberrations such as field curvature, magnification chromatic aberration, and coma. On the other hand, if f34 / f is above 5.500, it is not easy to reduce the diameter of the third and fourth lenses and the distance between the object and the image, making it difficult to achieve overall miniaturization of the wide-angle lens.

[0391] In contrast, in this embodiment, since condition 5 is satisfied, it has the advantages of easily and appropriately correcting various aberrations such as field curvature, magnification chromatic aberration, and coma, and it is easier to achieve overall miniaturization of the wide-angle lens.

[0392] Furthermore, in the wide-angle lens 1000, the focal distance of the third lens 130 is 10.047 mm, and the focal distance f of the entire lens system is 1.019 mm. Therefore, the following condition 6 is satisfied:

[0393] 5.000 < f3 / f < 10.000

[0394] In condition 6, if f3 / f is less than 5.000, the positive optical focal length of the third lens is too large, making it difficult to properly correct various aberrations such as field curvature, magnification chromatic aberration, and coma. On the other hand, if f3 / f is greater than 10.000, it is not easy to reduce the diameter of the third lens and the distance between the object and the image, making it difficult to achieve overall miniaturization of the wide-angle lens.

[0395] In contrast, in this embodiment, since condition 6 is satisfied, it has the advantages of easily and appropriately correcting various aberrations such as field curvature, magnification chromatic aberration, and coma, and it is easier to achieve overall miniaturization of the wide-angle lens.

[0396] Furthermore, in the wide-angle lens 1000, the object-image distance d is 13.381 mm, and the overall focal distance f of the lens system is 1.019 mm. Therefore, the following condition 7 is satisfied:

[0397] 11.000 < d / f < 15.000

[0398] In condition 7, if d / f is below 11.000, it is not easy to properly correct various aberrations. On the other hand, if d / f is above 15.000, the overall length of the lens system becomes too long.

[0399] In contrast, in this embodiment, since condition 7 is satisfied, it is easy to properly correct various aberrations, easily obtain excellent optical characteristics, and suppress the lens system from becoming too large while avoiding the overall length of the lens system becoming too long.

[0400] 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, and it is easy to achieve the miniaturization of the wide-angle lens as a whole.

[0401] 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.

[0402] 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.

[0403] 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.

Claims

1. A wide-angle lens, characterized in that, It includes a first lens, a second lens, a third lens, a fourth lens, an aperture, a fifth lens, a sixth lens, and a seventh lens arranged sequentially from the object side. The sixth lens and the seventh lens constitute a combined lens, and the number of lenses with optical power is seven. The first lens is a negative lens with its concave surface facing the image side. The second lens is a negative lens with its concave surface facing the image side. The third lens is a positive lens with its convex surface facing the image side. The fourth lens is a positive lens with its convex surface facing the image side. The fifth lens is a positive lens with its convex surface facing the object side and its convex surface facing the image side. The sixth lens is a negative lens with its concave surface facing the image side. The seventh lens is a positive lens with its convex surface facing the object side and its convex surface facing the image side. When the combined focal distance of the first lens, the second lens, the third lens, and the fourth lens is set to f1234, and the combined focal distance of the fifth lens, the sixth lens, and the seventh lens is set to f567, the following relationship is satisfied: 0.800 < f1234 / f567 < 3.000 When the focal distance of the entire wide-angle lens is set to f, the following relationship is satisfied: 2.500 < f1234 / f < 8.000 2.800 < f567 / f < 3.850 When the combined focal distance between the third lens and the fourth lens is set to f34, the following relationship is satisfied: 3.000 < f34 / f < 4.

500.

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, the following relationship is satisfied: -1.500 < f12 / f < -1.

000.

3. The wide-angle lens as described in claim 2, characterized in that, The following relationship must be satisfied: -1.500 < f12 / f < -1.

200.

4. The wide-angle lens as described in claim 1, characterized in that, When the focal distance of the third lens is set to f3, the following relationship is satisfied: 5.000 < f3 / f < 10.

000.

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

Images