Wide-angle lens

Abstract

The wide-angle lens comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens and an eighth lens which are sequentially arranged from an object plane to an image plane along an optical axis, in the direction from the object plane to the image plane, the first lens is a convex-concave lens and has negative focal power; the second lens is a convex-concave lens and has negative focal power; the third lens has positive focal power; the fourth lens is a biconvex lens and has positive focal power; or the fourth lens is a concave-convex lens and has negative focal power; the fifth lens is a biconvex lens and has positive focal power; the sixth lens is a biconcave lens and has negative focal power; the seventh lens is a biconvex lens and has positive focal power; the eighth lens is a paraxial region convex-concave lens and an off-axial region concave-convex lens, and has negative focal power; the sixth lens and the seventh lens form a balsaming lens. The wide-angle lens has the advantages of large aperture, large target surface, low chromatic aberration, low distortion, high image quality and the like.

Description

Technical Field

[0001] This utility model relates to the field of optical lens technology, and in particular to a wide-angle lens. Background Technology

[0002] Wide-angle lenses are renowned for their ultra-wide field of view and are widely used in panoramic photography, virtual reality, and surveillance. With continuous technological advancements, the market demand for wide-angle lenses with high image quality and low chromatic aberration is constantly increasing. However, mainstream wide-angle lenses generally suffer from low image quality and significant chromatic aberration, making them unsuitable for new application scenarios and wider adoption. Utility Model Content

[0003] This invention provides a wide-angle lens to achieve a wide-angle lens design with excellent characteristics such as large aperture, large target area, low chromatic aberration, low distortion, and high image quality.

[0004] The wide-angle lens provided by this utility model includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens arranged sequentially along the optical axis from the object plane to the image plane; in the direction from the object plane to the image plane,

[0005] The first lens is a convex-concave lens with negative optical power;

[0006] The second lens is a convex-concave lens with negative optical power;

[0007] The third lens has positive optical power;

[0008] The fourth lens is a biconvex lens with positive optical power; or, the fourth lens is a concave-convex lens with negative optical power.

[0009] The fifth lens is a biconvex lens with positive optical power;

[0010] The sixth lens is a biconcave lens with negative optical power;

[0011] The seventh lens is a biconvex lens with positive optical power;

[0012] The eighth lens is a convex-concave lens in the paraxial region and a concave-convex lens in the off-axis region, and has negative optical power;

[0013] The sixth and seventh lenses together form a cemented lens.

[0014] Optionally, the first lens is a glass spherical lens;

[0015] The second, third, fourth, fifth, sixth, seventh, and eighth lenses are all plastic aspherical lenses.

[0016] Optionally, the third lens is a biconvex lens or a biconcave lens.

[0017] Optionally, the optical power of the wide-angle lens is The optical power of the first lens is: The optical power of the second lens is The optical power of the third lens is The optical power of the fourth lens is The optical power of the fifth lens is The optical power of the sixth lens is The optical power of the seventh lens is The optical power of the cemented lens is The optical power of the eighth lens is in:

[0018]

[0019] Optionally, the Abbe number of the sixth lens is vd6, the Abbe number of the seventh lens is vd7, the combined focal length of the sixth and seventh lenses is F67, and the focal length of the wide-angle lens is F, where:

[0020] 20.7≤|vd7-vd6|≤36.5; 2≤F67 / F≤57.

[0021] Optionally, the refractive index of the third lens is nd3, and the Abbe number of the third lens is vd3, where:

[0022] 1.8 <nd3<2;22<vd3<26。

[0023] Optionally, the entrance pupil diameter of the wide-angle lens is EPD, and the focal length of the wide-angle lens is F, where:

[0024] F / EPD≤1.85.

[0025] Optionally, the distance from the center of the optical axis on the image side of the eighth lens to the image plane is BFL, the distance from the center of the optical axis on the object side of the first lens to the image plane is TTL, and the focal length of the wide-angle lens is F, where:

[0026] TTL / F < 8; BFL / F > 0.08.

[0027] Optionally, a wide-angle lens may also include an aperture stop;

[0028] The aperture stop is located in the optical path between the fourth and fifth lenses.

[0029] Optionally, the fourth lens has a focal length of F4, the fifth lens has a focal length of F5, and the wide-angle lens has a focal length of F, where:

[0030] -23 < (F4 + F5) / F < 7.

[0031] The technical solution of this utility model embodiment achieves a wide-angle lens design with large aperture, large target surface, low chromatic aberration, low distortion, and high image quality by using eight lenses and reasonably configuring the optical power, shape, and bonding state of each lens.

[0032] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this utility model, nor is it intended to limit the scope of this utility model. Other features of this utility model will become readily apparent from the following description. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0034] Figure 1 This is a schematic diagram of the structure of a wide-angle lens provided in Embodiment 1 of this utility model;

[0035] Figure 2 This is a spherical aberration curve of a wide-angle lens provided in Embodiment 1 of this utility model;

[0036] Figure 3 This is a ray fan diagram of a wide-angle lens provided in Embodiment 1 of this utility model;

[0037] Figure 4 This is a field curvature distortion diagram of a wide-angle lens provided in Embodiment 1 of this utility model;

[0038] Figure 5 This is a dot diagram of a wide-angle lens provided in Embodiment 1 of this utility model;

[0039] Figure 6 This is a schematic diagram of the structure of a wide-angle lens provided in Embodiment 2 of this utility model;

[0040] Figure 7 This is a spherical aberration curve of a wide-angle lens provided in Embodiment 2 of this utility model;

[0041] Figure 8 This is a ray fan diagram of a wide-angle lens provided in Embodiment 2 of this utility model;

[0042] Figure 9 This is a field curvature distortion diagram of a wide-angle lens provided in Embodiment 2 of this utility model;

[0043] Figure 10 This is a dot diagram of a wide-angle lens provided in Embodiment 2 of this utility model;

[0044] Figure 11 This is a schematic diagram of the structure of a wide-angle lens provided in Embodiment 3 of this utility model;

[0045] Figure 12 This is a spherical aberration curve of a wide-angle lens provided in Embodiment 3 of this utility model;

[0046] Figure 13 This is a ray fan diagram of a wide-angle lens provided in Embodiment 3 of this utility model;

[0047] Figure 14 This is a field curvature distortion diagram of a wide-angle lens provided in Embodiment 3 of this utility model;

[0048] Figure 15 This is a dot diagram of a wide-angle lens provided in Embodiment 3 of this utility model. Detailed Implementation

[0049] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0050] Various modifications and variations can be made to this application without departing from its spirit or scope, which will be apparent to those skilled in the art. Therefore, this application is intended to cover modifications and variations falling within the scope of the corresponding claims (the claimed technical solutions) and their equivalents. It should be noted that the embodiments provided in this application can be combined with each other without contradiction.

[0051] First, it should be noted that, unless otherwise defined, the technical or scientific terms used in this utility model should have the ordinary meaning understood by one of ordinary skill in the art to which this utility model pertains. The terms "first," "second," and similar terms used in this utility model do not indicate any order, quantity, or importance, but are merely used to distinguish different components. The terms "comprising" and similar terms mean that the element or object preceding the word encompasses the elements or objects listed after the word and their equivalents, but do not exclude other elements or objects. Furthermore, the shapes and sizes of the components in the accompanying drawings do not reflect actual proportions and are only intended to illustrate the content of this utility model.

[0052] Example 1

[0053] Figure 1 This is a structural schematic diagram of a wide-angle lens provided in Embodiment 1 of this utility model, as shown below. Figure 1 As shown, the wide-angle lens provided in this embodiment of the present invention includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, and an eighth lens L8 arranged sequentially along the optical axis from the object plane to the image plane. In the direction from the object plane to the image plane, the first lens L1 is a convex-concave lens with negative optical power; the second lens L2 is a convex-concave lens with negative optical power; the third lens L3 is a biconvex lens with positive optical power; the fourth lens L4 is a concave-convex lens with negative optical power; the fifth lens L5 is a biconvex lens with positive optical power; the sixth lens L6 is a biconcave lens with negative optical power; the seventh lens L7 is a biconvex lens with positive optical power; and the eighth lens L8 is a convex-concave lens in the paraxial region and a concave-convex lens in the off-axis region, with negative optical power. The sixth lens L6 and the seventh lens L7 form a cemented lens.

[0054] Reference Figure 1 For any lens, the surface of the lens adjacent to the object plane can be called the object-side surface, and the surface of the lens adjacent to the image plane can be called the image-side surface. Specifically, for the aforementioned convex-concave lenses, such as the first lens L1 and the second lens L2, the object-side surface of the lens convexes towards the object plane, and the image-side surface is concave towards the image plane. For the aforementioned biconvex lenses, such as the fifth lens L5 and the seventh lens L7, the object-side surface of the lens convexes towards the object plane, and the image-side surface convexes towards the image plane. For the aforementioned biconcave lenses, such as the sixth lens L6, the object-side surface is concave towards the object plane, and the image-side surface is concave towards the image plane. For the aforementioned concave-convex lenses, such as the fourth lens L4, the object-side surface is concave towards the object plane, and the image-side surface convex towards the image plane. Notably, the paraxial and off-axis regions of the eighth lens L8 have different shapes. The paraxial region is the area close to the optical axis, and the off-axis region is the area far from the optical axis, located above and below the paraxial region. Specifically, in the paraxial region, the object-side surface of the eighth lens L8 convexes towards the object plane, while the image-side surface is concave towards the image plane. In the off-axis region, the object-side surface of the eighth lens L8 is concave towards the object plane, and the image-side surface convex towards the image plane. By rationally setting the surface shape of each lens, the overall wide-angle lens structure can be ensured to be compact, with high lens integration. This also helps to increase the light transmission of the system, achieving a large aperture, low chromatic aberration, and high image quality.

[0055] Optical power is equal to the difference between the convergence of the image-side beam and the convergence of the object-side beam; it characterizes the ability of an optical system to deflect light. The larger the absolute value of the optical power, the stronger the bending ability of light; the smaller the absolute value, the weaker the bending ability. When the optical power is positive, the refraction of light is converging; when the optical power is negative, the refraction of light is diverging. Optical power can be used to characterize a single refractive surface of a lens (i.e., one surface of the lens), a single lens, or a system formed by multiple lenses (i.e., a lens group). In the wide-angle lens provided in this embodiment, all lenses can be fixed to a single lens barrel (…). Figure 1 (Not shown in the image). This embodiment, by rationally allocating the optical power of each lens, ensures smooth light propagation, preventing excessive refraction on any single surface and avoiding large aberrations. This results in high image quality and facilitates the creation of a large aperture and a large image sensor. In this embodiment, the wide-angle lens has an image sensor diameter of 8.8mm and an imaging range of 165°.

[0056] It should be noted that, Figure 1 The surface shape of the fourth lens L4 shown is not unique. In other embodiments, the fourth lens L4 can be a biconvex lens with positive optical power.

[0057] Furthermore, by using a cemented lens composed of a sixth lens L6 and a seventh lens L7, this embodiment effectively reduces the air gap between the sixth lens L6 and the seventh lens L7, thereby further reducing the overall length of the lens. In addition, the cemented lens arrangement reduces chromatic aberration through the complementary chromatic aberration of the positive and negative optical power surfaces of the cemented lenses. Simultaneously, the residual chromatic aberration balances the chromatic aberration caused by other components of the wide-angle lens, allowing various aberrations of the wide-angle lens to be fully corrected, improving imaging performance. Under the premise of a compact structure, it can improve resolution, optimize optical performance such as distortion, and reduce light loss caused by reflections between lenses, increasing illumination and thus improving image quality and the sharpness of the lens image. Furthermore, the cemented lens arrangement also reduces the number of assembly components between lenses, simplifying the assembly process in lens manufacturing, reducing costs, and reducing tolerance sensitivity issues such as tilting / eccentricity of lens units during assembly.

[0058] In summary, by using eight lenses and rationally configuring the optical power, shape, and bonding state of each lens, this utility model embodiment achieves a wide-angle lens design with a large aperture, large target surface, low chromatic aberration, low distortion, and high image quality.

[0059] Based on the above embodiments, referring to Figure 1Optionally, the first lens L1 is a glass spherical lens; the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, the seventh lens L7 and the eighth lens L8 are all plastic aspherical lenses.

[0060] Specifically, aspherical lenses are characterized by a continuous change in curvature from the center to the periphery. Unlike spherical lenses, which have a constant curvature from the center to the periphery, aspherical lenses have superior curvature radius characteristics, offering advantages in improving distortion and astigmatism. Using aspherical lenses can minimize aberrations that occur during image formation, thereby enhancing the lens's image quality. Spherical lenses, on the other hand, have a constant curvature from the center to the periphery, ensuring a simpler lens configuration.

[0061] Furthermore, the material of the plastic aspherical lens can be any plastic known to those skilled in the art, and the material of the glass spherical lens can be any type of glass known to those skilled in the art. This embodiment of the present invention will not elaborate on or limit the specific materials used. Glass lenses have a lower coefficient of thermal expansion and better stability. When the ambient temperature of the lens changes significantly, this helps maintain the stability of the lens's focal length. Plastic lenses are significantly cheaper than glass lenses, thus reducing the overall cost of the lens.

[0062] This embodiment uses a combination of glass and plastic lenses. By setting the first lens L1 to be a glass spherical lens and the remaining lenses to be plastic aspherical lenses, the cost of the lens can be effectively controlled, and it is also beneficial to correct aberrations by using aspherical lenses.

[0063] Reference Figure 1 It should be noted that, Figure 1 The illustration uses a biconvex lens (L3) as an example only and is not intended to be limiting. In other embodiments, when the third lens (L3) is an aspherical lens, it may optionally be a biconcave lens. Due to the influence of the plastic material and the aspherical surface shape, a biconcave lens can also have positive optical power, as illustrated in subsequent embodiments.

[0064] Reference Figure 1 Optionally, the optical power of the wide-angle lens is... The optical power of the first lens L1 is: The optical power of the second lens L2 is: The optical power of the third lens L3 is: The optical power of the fourth lens L4 is The optical power of the fifth lens L5 is The optical power of the sixth lens L6 is The optical power of the seventh lens L7 is The optical power of the cemented lens is The optical power of the eighth lens L8 is in:

[0065]

[0066]

[0067] Specifically, by limiting the optical power of each lens and the optical power of the wide-angle lens as described above, light can be made to travel smoothly during propagation, which is beneficial for achieving lens designs with large aperture, low chromatic aberration, low distortion, and high image quality. For example, the first lens L1 and the second lens L2 simultaneously bear the negative optical power of the front group. By rationally designing the optical power of the first lens L1 and the second lens L2, light can be focused, reducing the aperture size of the light in the subsequent system and balancing aberration distribution.

[0068] Reference Figure 1 Optionally, the Abbe number of the sixth lens L6 is vd6, the Abbe number of the seventh lens L7 is vd7, the combined focal length of the sixth lens L6 and the seventh lens L7 is F67, and the focal length of the wide-angle lens is F, where: 20.7≤|vd7-vd6|≤36.5; 2≤F67 / F≤57.

[0069] Specifically, by setting the Abbe number of each lens in a cemented lens and the focal length relationship between the cemented lens and the wide-angle lens as described above, chromatic aberration can be balanced and imaging performance improved.

[0070] Reference Figure 1 Optionally, the refractive index of the third lens L3 is nd3, and the Abbe number of the third lens L3 is vd3, where: 1.8 <nd3<2;22<vd3<26。

[0071] Specifically, the third lens L3 is made of a high refractive index, low Abbe number material. This design can prevent the incident light from diverging too much when passing through the third lens L3, which would lead to an excessively large incident angle. This helps to reduce the aperture size of the light in the subsequent system and balance the aberration distribution.

[0072] Reference Figure 1 Optionally, the entrance pupil diameter of the wide-angle lens is EPD, and the focal length of the wide-angle lens is F, where: F / EPD≤1.85.

[0073] Specifically, if the lens focal length F and the lens entrance pupil diameter EPD satisfy the above conditions, it indicates that the lens has a large aperture, ensuring a large amount of light transmission and clear imaging even when the lens is working at night. With a fixed focal length, the larger the lens entrance pupil diameter, the larger the lens aperture. In this embodiment, the lens aperture F.NO ≤ 1.85.

[0074] Reference Figure 1 Optionally, the distance from the optical axis center on the image side of the eighth lens L8 to the image plane is BFL, the distance from the optical axis center on the object side of the first lens L1 to the image plane is TTL, and the focal length of the wide-angle lens is F, where: TTL / F < 8; BFL / F > 0.08.

[0075] Here, BFL can be understood as the back focal length of a wide-angle lens, and TTL can be understood as the total length of a wide-angle lens. When the above characteristics are met, the size of the wide-angle lens is further reduced, which is conducive to the miniaturization of the wide-angle lens. On the basis of miniaturization, the large back focal length ratio can provide sufficient space for the rear structure design of the wide-angle lens, which is conducive to the assembly of the wide-angle lens, improves the production yield, and reduces costs.

[0076] Reference Figure 1 Optionally, the wide-angle lens also includes an aperture stop 110; the aperture stop 110 is located in the optical path between the fourth lens L4 and the fifth lens L5. By properly setting the position of the aperture stop 110, the coma generated by the system can be significantly reduced.

[0077] Reference Figure 1 Optionally, the focal length of the fourth lens L4 is F4, the focal length of the fifth lens L5 is F5, and the focal length of the wide-angle lens is F, where: -23 < (F4 + F5) / F < 7.

[0078] Specifically, by limiting the focal length relationship between the fourth lens L4 and the fifth lens L5 and the wide-angle lens as described above, and by combining them appropriately, the aberrations caused by light passing through the aperture 110 can be balanced.

[0079] Reference Figure 1 Optionally, the wide-angle lens also includes a filter 120, which is disposed on the image-side side of the eighth lens L8. Specifically, by placing the filter 120 between the eighth lens L8 and the image plane (IMA), unwanted stray light can be filtered out, thereby improving the image quality of the wide-angle lens.

[0080] As described above, in this embodiment, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, the seventh lens L7, and the eighth lens L8 are aspherical lenses.

[0081] The surface shape of an aspherical lens satisfies the following formula:

[0082]

[0083] Where Z represents the sag of the aspherical surface; r represents the radial coordinate perpendicular to the optical axis; c represents the curvature of the fitted sphere, which is numerically the reciprocal of the radius of curvature; k represents the conic section constant; and A, B, C, D, E, F, and G represent the 4th, 6th, 8th, 10th, 12th, 14th, and 16th order coefficients of the aspherical polynomial, respectively.

[0084] For example, Table 1 details the specific optical physical parameters of each lens in the wide-angle lens provided in Embodiment 1 of this utility model, using a feasible implementation method. The wide-angle lens in Table 1 corresponds to... Figure 1 The wide-angle lens shown.

[0085] Table 1 Design values ​​of optical physical parameters for wide-angle lenses

[0086] Face number Surface type radius of curvature thickness Materials (nd) Materials (vd) Half diameter S1 Standard surface 14.2489 2.0109 1.87 45.5 8.321 S2 Standard surface 4.0764 1.9493 8.321 S3 aspherical 2.4421 0.4997 1.50 42.3 3.718 S4 aspherical 1.6089 3.3090 3.718 S5 aspherical 17.1323 2.5000 1.9 25.9 2.562 S6 aspherical -12.0502 0.1454 2.562 S7 aspherical -7.0304 0.9306 1.66 20.4 1.913 S8 aspherical -8.9812 0.0778 1.913 STO Standard surface INF 0.0287 1.593 S12 aspherical 3.6339 1.0642 1.50 81.6 1.614 S13 aspherical -5.4384 0.8183 1.614 S14 aspherical -47.1695 0.3798 1.64 23.5 2.227 S15 aspherical 2.0818 1.9809 1.54 55.7 2.227 S16 aspherical -7.9556 0.4249 2.227 S17 aspherical 7.0500 0.6785 1.54 55.7 3.166 S18 aspherical 3.2279 0.3419 3.166 S19 Standard surface INF 0.7200 1.52 64.2 2.562 S20 Standard surface INF 0.8401 IMA Standard surface INF

[0087] The surface number is determined by the order of the lens surfaces. For example, surface number "S1" represents the object-side surface of the first lens, surface number "S2" represents the image-side surface of the first lens, and so on. "STO" represents the aperture stop of the lens. The radius of curvature represents the curvature of the lens surface. A positive value indicates that the surface bends towards the object surface with the center closer to the image surface, while a negative value indicates that the surface bends towards the image surface with the center closer to the object surface. "INF" indicates that the surface is flat and the radius of curvature is infinite. The thickness represents the axial distance between the center of the current surface and the next surface. Due to the different number of digits for each parameter, there may be focusing errors. Therefore, the thickness of surface S18 has a certain range and can be adjusted as needed to achieve a clear focus. The material (nd) represents the refractive index, which is the ability of the material between the current surface and the next surface to deflect light. A space indicates that the current position is air with a refractive index of 1. The material (vd) represents the Abbe number, which is the dispersion characteristic of the material between the current surface and the next surface. A space indicates that the current position is air. The half-diameter represents the half-aperture of the lens.

[0088] For example, Table 2 details the aspherical coefficients of each lens in this embodiment one of feasible implementations.

[0089] Table 2 Design values ​​of aspherical coefficients for various lenses in wide-angle lenses.

[0090] Face number k A B C D E F G S3 -0.82 -1.5210E-02 1.2547E-03 -7.7188E-05 1.8022E-06 3.0666E-08 -2.4807E-09 -7.7641E-12 S4 -0.72 -1.6569E-02 3.4748E-05 7.1815E-04 -2.1980E-04 3.0481E-05 -1.8497E-06 8.9774E-09 S5 -23.04 2.7628E-04 1.3020E-04 -5.2498E-05 1.3489E-05 -1.2358E-06 5.3797E-08 2.7093E-09 S6 -117.31 -4.5999E-04 8.0264E-05 -1.0929E-04 5.3446E-06 -5.7980E-07 3.3600E-07 -2.2770E-08 S7 -44.31 2.7189E-04 -5.5753E-04 -2.0081E-04 2.4241E-06 -2.4116E-06 -2.8293E-07 5.4142E-08 S8 -68.12 -4.2872E-03 1.1838E-03 -1.4964E-04 -3.4959E-05 5.4898E-06 -1.0239E-06 1.5379E-07 S12 -0.06 -2.3981E-03 1.7344E-04 -3.0804E-04 2.1211E-04 -2.6661E-05 -1.2236E-05 3.5776E-06 S13 2.95 -2.4392E-03 4.3665E-04 4.7899E-04 -1.0209E-04 7.5518E-06 -7.8140E-07 1.1981E-06 S14 382.22 -8.4967E-03 2.3386E-03 -1.1557E-03 -1.4706E-05 3.2939E-04 -1.2261E-04 1.3981E-05 S15 0.04 -3.2132E-03 -4.7554E-03 1.6129E-03 -7.7281E-04 1.2993E-04 3.1064E-05 -9.6004E-06 S16 3.72 -3.3118E-03 2.2277E-03 -9.7481E-05 -1.4207E-05 6.6124E-06 2.4976E-06 -5.7820E-07 S17 -1.30 -4.1284E-02 5.0666E-03 -1.2420E-04 -1.1804E-04 7.5212E-06 3.3540E-06 -4.1038E-07 S18 -6.84 -2.0092E-02 2.8955E-03 -3.1959E-04 1.2356E-05 5.2540E-07 -3.1173E-08 -2.3533E-09

[0091] Where -1.5210E-02 indicates that the coefficient A of surface number S3 is -1.5210*10. -2 And so on.

[0092] The wide-angle lens provided in this embodiment achieves the following technical specifications:

[0093] Focal length: F = 2.40mm;

[0094] Aperture: F.NO = 1.85;

[0095] Field of view: 165°;

[0096] Overall optical length: 18.7mm;

[0097] Image plane diameter: Φ8.8mm.

[0098] Furthermore, Figure 2 This is a spherical aberration curve of a wide-angle lens provided in Embodiment 1 of this utility model, as shown below. Figure 2 As shown, the chromatic aberration of this wide-angle lens at different wavelengths (0.470μm, 0.487μm, 0.546μm, 0.587μm, 0.656μm) is within 3μm. The curves of different wavelengths are relatively concentrated, indicating that the chromatic aberration of this wide-angle lens is very small. Therefore, it can be seen that this wide-angle lens can correct chromatic aberration well.

[0099] Figure 3 This is a ray fan pattern of a wide-angle lens provided in Embodiment 1 of this utility model, such as... Figure 3 As shown, the horizontal axis of the ray fan diagram represents the distance a ray deviates from the center of the entrance pupil as it passes through it, and the vertical axis represents the distance the corresponding ray deviates from the principal ray on the image plane. It is important to note that the principal ray is the ray that passes through the center of the entrance pupil; as shown... Figure 3 As shown, the curve of the ray fan diagram is flat, indicating that the lens aberration has been well corrected.

[0100] Figure 4 This is a field curvature distortion diagram of a wide-angle lens provided in Embodiment 1 of this utility model, such as... Figure 4 As shown, there are two coordinate systems. In the left coordinate system, the horizontal coordinate represents the magnitude of the field curvature in mm; the vertical coordinate represents the normalized image height, which has no unit. Here, T represents the meridion and S represents the sagitta. Figure 4 As can be seen from the left coordinate system, the wide-angle lens provided in Example 1 effectively controls the field curvature of light with wavelengths from 0.470μm to 0.656μm, ensuring a small difference in image quality between the center and the periphery during imaging. In the right coordinate system, the horizontal axis represents the magnitude of distortion, expressed as a percentage; the vertical axis represents the normalized image height, which has no unit. Figure 4 As can be seen from the coordinate system on the right, the distortion of the wide-angle lens provided in Embodiment 1 of this application has been effectively controlled.

[0101] Figure 5This is a dot plot of a wide-angle lens provided in Embodiment 1 of this utility model. The dot plot refers to the pattern formed by the dispersion of light rays emitted from a single light source across a certain area. Due to aberrations, the intersection points of these rays with the image plane are no longer concentrated at a single point. The dot plot is one of the most commonly used evaluation methods in modern optical design. The distribution of points in the dot plot can approximately represent the degree of light concentration and reflect the imaging quality of the system. For example... Figure 5 As shown, the wide-angle lens provided in this embodiment exhibits relatively concentrated and uniformly distributed diffusion patterns for visible light of different wavelengths (0.470μm, 0.487μm, 0.546μm, 0.587μm, and 0.656μm) across various fields of view. There is no significant separation of diffusion patterns along wavelengths in any particular field of view, indicating the absence of noticeable purple fringing. Furthermore, the root mean square radius (RMS radius) of visible light of different wavelengths at each field of view position of this wide-angle lens is less than 2.5μm, demonstrating low chromatic aberration and aberrations across the entire field of view. This solves the purple fringing problem in visible light imaging and enables high-resolution imaging.

[0102] Example 2

[0103] Figure 6 This is a schematic diagram of the structure of a wide-angle lens provided in Embodiment 2 of this utility model, as shown below. Figure 6 As shown, the wide-angle lens provided in this embodiment of the present invention includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, and an eighth lens L8 arranged sequentially along the optical axis from the object plane to the image plane. In the direction from the object plane to the image plane, the first lens L1 is a convex-concave lens with negative optical power; the second lens L2 is a convex-concave lens with negative optical power; the third lens L3 has positive optical power; the fifth lens L5 is a biconvex lens with positive optical power; the sixth lens L6 is a biconcave lens with negative optical power; the seventh lens L7 is a biconvex lens with positive optical power; and the eighth lens L8 is a convex-concave lens in the paraxial region and a concave-convex lens in the off-axis region, with negative optical power. The sixth lens L6 and the seventh lens L7 form a cemented lens.

[0104] The difference between this embodiment and Embodiment 1 is that the third lens L3 is a biconcave lens; the fourth lens L4 is a biconvex lens with positive optical power.

[0105] For example, Table 3 details the specific optical physical parameters of each lens in the wide-angle lens provided in Embodiment 2 of this utility model, according to a feasible implementation. The wide-angle lens in Table 3 corresponds to... Figure 6 The wide-angle lens shown.

[0106] In Table 3, the surface numbers are assigned according to the surface sequence of each lens. For example, surface number "S1" represents the object-side surface of the first lens, surface number "S2" represents the image-side surface of the first lens, and so on. "STO" represents the aperture stop of the lens. The radius of curvature represents the curvature of the lens surface. A positive value indicates that the surface bends towards the object surface with the center closer to the image surface, while a negative value indicates that the surface bends towards the image surface with the center closer to the object surface. "INF" indicates that the surface is flat and the radius of curvature is infinite. The thickness represents the axial distance between the center of the current surface and the next surface. Due to the different number of digits in the parameter values, there may be focusing errors. Therefore, the thickness of surface S18 has a certain range and can be adjusted as needed to achieve a clear focus. Material (nd) represents the refractive index, which is the ability of the material between the current surface and the next surface to deflect light. A blank space indicates that the current position is air with a refractive index of 1. Material (vd) represents the Abbe number, which is the dispersion characteristic of the material between the current surface and the next surface. A blank space indicates that the current position is air. Half-diameter represents the half-aperture of the lens.

[0107] Table 3 Design values ​​of optical physical parameters for wide-angle lenses

[0108] Face number Surface type radius of curvature thickness Materials (nd) Materials (vd) Half diameter S1 Standard surface 17.6923 1.9937 1.74 50 7.629 S2 Standard surface 6.2790 0.0970 7.629 S3 aspherical 2.7349 0.5205 1.82 56.3 4.349 S4 aspherical 1.6032 3.5022 4.349 S5 aspherical 69.5633 1.9758 1.85 24 2.741 S6 aspherical -448.2354 0.3734 2.741 S7 aspherical 55.2182 1.6491 1.75 52.7 2.291 S8 aspherical -8.2411 0.3101 2.291 STO Standard surface INF 0.0282 1.514 S12 aspherical 3.6264 0.9304 1.52 73.5 1.616 S13 aspherical -15.7054 1.0483 1.616 S14 aspherical -36.4719 0.3754 1.72 73.5 2.386 S15 aspherical 2.7651 2.4821 1.64 60 2.386 S16 aspherical -3.1309 0.0301 2.386 S17 aspherical 5.4969 0.5059 1.66 20.7 3.155 S18 aspherical 2.2386 0.2431 3.155 S19 Standard surface INF 0.7200 1.52 64.2 3.627 S20 Standard surface INF 1.2951 3.627 IMA Standard surface INF

[0109] For example, Table 4 details the aspherical coefficients of each lens in this embodiment two according to a feasible implementation.

[0110] Table 4. Design values ​​of aspheric coefficients for various lenses in wide-angle lenses.

[0111] Face number k A B C D E F G S3 -0.87 -9.4205E-03 5.2023E-04 -2.2948E-05 4.9683E-07 -3.3233E-09 -5.5305E-10 2.2894E-11 S4 -0.73 -1.2160E-02 -2.8024E-04 1.8644E-04 -4.9467E-05 5.6081E-06 -2.2183E-07 -1.3329E-08 S5 -846.24 -2.2674E-03 4.1720E-05 -4.6666E-06 3.0819E-06 -4.9788E-07 -2.3384E-08 5.8436E-09 S6 -2889 1.6718E-03 2.6171E-04 -2.5687E-05 3.3129E-06 -4.9185E-07 -1.4050E-07 2.6731E-08 S7 282.28 5.4266E-03 -1.2677E-05 -1.6253E-06 8.8224E-06 -3.6920E-07 -1.4900E-07 4.0756E-08 S8 -32.12 -4.1667E-03 6.5838E-04 3.9053E-05 6.0499E-06 3.0104E-07 -7.4669E-07 2.4598E-07 S12 0.01 -2.9440E-04 -9.7107E-04 -7.3122E-05 1.2680E-04 -1.2605E-05 -9.4547E-06 2.9803E-06 S13 38.03 -2.6626E-03 -7.8670E-04 1.7628E-04 -6.4580E-06 -1.2217E-06 1.3520E-06 9.1165E-07 S14 382.22 -6.6778E-03 -9.2018E-05 -1.5852E-04 1.4683E-05 4.1904E-05 -1.4186E-05 2.4127E-06 S15 0.28 -2.8731E-03 1.5890E-03 -4.1418E-04 -1.0798E-04 4.6516E-05 -4.1880E-06 -1.0287E-07 S16 -5.53 -3.2365E-04 -1.1344E-03 -5.3605E-05 3.3498E-05 1.6949E-06 -1.4650E-06 1.2926E-07 S17 -63.43 -2.2790E-02 5.8950E-04 -8.7992E-05 -3.3313E-05 1.7938E-06 1.0573E-06 -2.3449E-07 S18 -8.31 -1.5662E-02 1.2654E-03 -1.0294E-04 3.8607E-06 6.5072E-08 -3.2583E-08 2.1257E-09

[0112] Where -9.4205E-03 indicates that the coefficient A of surface number S3 is -9.4205*10 -3 And so on.

[0113] The wide-angle lens provided in this embodiment achieves the following technical specifications:

[0114] Focal length: F = 2.42mm;

[0115] Aperture: F.NO = 1.85;

[0116] Field of view: 165°;

[0117] Overall optical length: 18.1 mm;

[0118] Image plane diameter: Φ8.8mm.

[0119] Furthermore, Figure 7 This is a spherical aberration curve of a wide-angle lens provided in Embodiment 2 of this utility model, as shown below. Figure 7As shown, the chromatic aberration of this wide-angle lens at different wavelengths (0.470μm, 0.487μm, 0.546μm, 0.587μm, 0.656μm) is within 3μm. The curves of different wavelengths are relatively concentrated, indicating that the chromatic aberration of this wide-angle lens is very small. Therefore, it can be seen that this wide-angle lens can correct chromatic aberration well.

[0120] Figure 8 This is a ray fan pattern of a wide-angle lens provided in Embodiment 2 of this utility model, such as... Figure 8 As shown, the horizontal axis of the ray fan diagram represents the distance a ray deviates from the center of the entrance pupil as it passes through it, and the vertical axis represents the distance the corresponding ray deviates from the principal ray on the image plane. It is important to note that the principal ray is the ray that passes through the center of the entrance pupil; as shown... Figure 8 As shown, the curve of the ray fan diagram is flat, indicating that the lens aberration has been well corrected.

[0121] Figure 9 This is a field curvature distortion diagram of a wide-angle lens provided in Embodiment 2 of this utility model, such as... Figure 9 As shown, there are two coordinate systems. In the left coordinate system, the horizontal coordinate represents the magnitude of the field curvature in mm; the vertical coordinate represents the normalized image height, which has no unit. Here, T represents the meridion and S represents the sagitta. Figure 9 As can be seen from the left coordinate system, the wide-angle lens provided in Example 2 effectively controls the field curvature of light with wavelengths from 0.470μm to 0.656μm, ensuring a small difference in image quality between the center and the periphery during imaging. In the right coordinate system, the horizontal axis represents the magnitude of distortion, expressed as a percentage; the vertical axis represents the normalized image height, which has no unit. Figure 9 As can be seen from the coordinate system on the right, the distortion of the wide-angle lens provided in Embodiment 2 of this application has been effectively controlled.

[0122] Figure 10 This is a dot plot of a wide-angle lens provided in Embodiment 2 of this utility model. A dot plot refers to the pattern formed by the dispersion of light rays emitted from a single light source across a certain area after passing through an optical system, due to aberrations. The dot plot is one of the most commonly used evaluation methods in modern optical design; the distribution of points in the dot plot can approximately represent the degree of light concentration and reflect the imaging quality of the system. For example... Figure 10As shown, the wide-angle lens provided in this embodiment exhibits relatively concentrated and uniformly distributed diffusion patterns for visible light of different wavelengths (0.470μm, 0.487μm, 0.546μm, 0.587μm, and 0.656μm) across various fields of view. There is no significant separation of diffusion patterns along wavelengths in any particular field of view, indicating the absence of noticeable purple fringing. Furthermore, the root mean square radius (RMS radius) of visible light of different wavelengths at each field of view position of this wide-angle lens is less than 2.5μm, demonstrating low chromatic aberration and aberrations across the entire field of view. This solves the purple fringing problem in visible light imaging and enables high-resolution imaging.

[0123] Example 3

[0124] Figure 11 This is a structural schematic diagram of a wide-angle lens provided in Embodiment 3 of this utility model, as shown below. Figure 11 As shown, the wide-angle lens provided in this embodiment of the present invention includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, and an eighth lens L8 arranged sequentially along the optical axis from the object plane to the image plane. In the direction from the object plane to the image plane, the first lens L1 is a convex-concave lens with negative optical power; the second lens L2 is a convex-concave lens with negative optical power; the third lens L3 has positive optical power; the fifth lens L5 is a biconvex lens with positive optical power; the sixth lens L6 is a biconcave lens with negative optical power; the seventh lens L7 is a biconvex lens with positive optical power; and the eighth lens L8 is a convex-concave lens in the paraxial region and a concave-convex lens in the off-axis region, with negative optical power. The sixth lens L6 and the seventh lens L7 form a cemented lens.

[0125] The difference between this embodiment and Embodiment 1 is that the third lens L3 is a biconcave lens; the fourth lens L4 is a biconvex lens with positive optical power.

[0126] For example, Table 5 details the specific optical physical parameters of each lens in the wide-angle lens provided in Embodiment 3 of this utility model, according to a feasible implementation. The wide-angle lens in Table 5 corresponds to... Figure 11 The wide-angle lens shown.

[0127] The surface number is determined by the order of the lens surfaces. For example, surface number "S1" represents the object-side surface of the first lens, surface number "S2" represents the image-side surface of the first lens, and so on. "STO" represents the aperture stop of the lens. The radius of curvature represents the curvature of the lens surface. A positive value indicates that the surface bends towards the object surface with the center closer to the image surface, while a negative value indicates that the surface bends towards the image surface with the center closer to the object surface. "INF" indicates that the surface is flat and the radius of curvature is infinite. The thickness represents the axial distance between the center of the current surface and the next surface. Due to the different number of digits for each parameter, there may be focusing errors. Therefore, the thickness of surface S18 has a certain range and can be adjusted as needed to achieve a clear focus. The material (nd) represents the refractive index, which is the ability of the material between the current surface and the next surface to deflect light. A space indicates that the current position is air with a refractive index of 1. The material (vd) represents the Abbe number, which is the dispersion characteristic of the material between the current surface and the next surface. A space indicates that the current position is air. The half-diameter represents the half-aperture of the lens.

[0128] Table 5 Design values ​​of optical physical parameters for wide-angle lenses

[0129] Face number Surface type radius of curvature thickness Materials (nd) Materials (vd) Half diameter S1 Standard surface 32.6091 0.6993 1.68 50 6.014 S2 Standard surface 7.4111 0.0980 6.014 S3 aspherical 2.6546 0.6317 1.72 60.9 3.987 S4 aspherical 1.6109 3.0556 3.987 S5 aspherical 79.9118 1.8884 1.88 23 2.691 S6 aspherical -105.8428 0.3282 2.691 S7 aspherical 49.7655 1.6728 1.75 64.3 2.390 S8 aspherical -8.3289 0.2392 2.390 STO Standard surface INF 0.0272 1.734 S12 aspherical 3.5550 1.0761 1.52 60 1.827 S13 aspherical -16.2306 0.9978 1.827 S14 aspherical -38.8516 0.3728 1.76 35 2.414 S15 aspherical 2.7824 2.5065 1.64 60 2.414 S16 aspherical -3.9334 0.1785 2.414 S17 aspherical 8.0526 0.5680 1.82 31.8 3.176 S18 aspherical 2.8881 0.4502 3.176 S19 Standard surface INF 0.7200 1.52 64.2 3.843 S20 Standard surface INF 1.0932 3.843 IMA Standard surface INF

[0130] For example, Table 6 details the aspherical coefficients of each lens in this embodiment three according to a feasible implementation.

[0131] In Table 6, -9.7410E-03 indicates that the coefficient A for surface number S3 is -9.7410*10. -3 And so on.

[0132] Table 6 Design values ​​of aspherical coefficients for various lenses in wide-angle lenses.

[0133] Face number k A B C D E F G S3 -0.90 -9.7410E-03 5.1172E-04 -2.3143E-05 4.9128E-07 -3.6566E-09 -5.4360E-10 2.5797E-11 S4 -0.73 -1.3343E-02 -6.4838E-05 1.9260E-04 -4.9991E-05 5.5927E-06 -2.2508E-07 -1.2685E-08 S5 -1900 -2.1183E-03 3.6040E-05 -3.9035E-06 3.5064E-06 -4.4499E-07 -1.9300E-08 4.3088E-09 S6 987.23 1.5298E-03 2.7188E-04 -2.4214E-05 3.2251E-06 -6.1143E-07 -1.5577E-07 2.7996E-08 S7 234.90 5.4460E-03 -4.3638E-05 -1.5302E-05 6.7542E-06 -6.8310E-07 -1.8716E-07 4.0420E-08 S8 -29.51 -4.4346E-03 5.2857E-04 8.0945E-06 3.6095E-06 7.9787E-07 -6.5236E-07 1.1194E-07 S12 -0.01 -4.8674E-04 -8.5185E-04 -4.3655E-05 1.2753E-04 -1.1507E-05 -9.7875E-06 2.4277E-06 S13 21.27 -2.0336E-03 -6.2233E-04 2.0827E-04 4.0204E-06 -4.0088E-06 -2.0359E-06 1.3191E-06 S14 382.22 -5.7966E-03 1.1503E-04 -1.2095E-04 1.6987E-05 4.1498E-05 -1.5068E-05 2.0358E-06 S15 0.30 -3.5767E-03 2.0141E-03 -2.9007E-04 -1.0141E-04 4.3835E-05 -5.5148E-06 2.0007E-07 S16 -4.30 6.5974E-04 -1.0233E-03 -5.0878E-05 3.6634E-05 2.1609E-06 -1.4775E-06 9.7788E-08 S17 -109.15 -2.5722E-02 9.4363E-04 -4.6284E-05 -2.8205E-05 2.5168E-06 1.0888E-06 -2.5223E-07 S18 -10.45 -1.6113E-02 1.3375E-03 -9.7074E-05 3.7309E-06 2.0295E-08 -3.7593E-08 2.1130E-09

[0134] The wide-angle lens provided in this embodiment achieves the following technical specifications:

[0135] Focal length: F = 3.1mm;

[0136] Aperture: F.NO = 1.85;

[0137] Field of view: 165°;

[0138] Overall optical length: 16.6mm;

[0139] Image plane diameter: Φ8.8mm.

[0140] Furthermore, Figure 12 This is a spherical aberration curve of a wide-angle lens provided in Embodiment 3 of this utility model, as shown below. Figure 12As shown, the chromatic aberration of this wide-angle lens at different wavelengths (0.470μm, 0.487μm, 0.546μm, 0.587μm, 0.656μm) is within 3μm. The curves of different wavelengths are relatively concentrated, indicating that the chromatic aberration of this wide-angle lens is very small. Therefore, it can be seen that this wide-angle lens can correct chromatic aberration well.

[0141] Figure 13 This is a ray fan pattern of a wide-angle lens provided in Embodiment 3 of this utility model, such as... Figure 13 As shown, the horizontal axis of the ray fan diagram represents the distance a ray deviates from the center of the entrance pupil as it passes through it, and the vertical axis represents the distance the corresponding ray deviates from the principal ray on the image plane. It is important to note that the principal ray is the ray that passes through the center of the entrance pupil; as shown... Figure 13 As shown, the curve of the ray fan diagram is flat, indicating that the lens aberration has been well corrected.

[0142] Figure 14 This is a field curvature distortion diagram of a wide-angle lens provided in Embodiment 3 of this utility model, such as... Figure 14 As shown, there are two coordinate systems. In the left coordinate system, the horizontal coordinate represents the magnitude of the field curvature in mm; the vertical coordinate represents the normalized image height, which has no unit. Here, T represents the meridion and S represents the sagitta. Figure 14 As can be seen from the left coordinate system, the wide-angle lens provided in Example 3 effectively controls the field curvature of light with wavelengths from 0.470μm to 0.656μm, ensuring a small difference in image quality between the center and the periphery during imaging. In the right coordinate system, the horizontal axis represents the magnitude of distortion, expressed as a percentage; the vertical axis represents the normalized image height, which has no unit. Figure 14 As can be seen from the coordinate system on the right, the distortion of the wide-angle lens provided in Embodiment 3 of this application has been effectively controlled.

[0143] Figure 15 This is a dot plot of a wide-angle lens provided in Embodiment 3 of this utility model. A dot plot refers to the pattern formed by the dispersion of light rays emitted from a single light source across a certain area after passing through an optical system, due to aberrations. The dot plot is one of the most commonly used evaluation methods in modern optical design; the distribution of points in the dot plot can approximately represent the degree of light concentration and reflect the imaging quality of the system. For example... Figure 15As shown, the wide-angle lens provided in this embodiment exhibits relatively concentrated and uniformly distributed diffusion patterns for visible light of different wavelengths (0.470μm, 0.487μm, 0.546μm, 0.587μm, and 0.656μm) across various fields of view. There is no significant separation of diffusion patterns along wavelengths in any particular field of view, indicating the absence of noticeable purple fringing. Furthermore, the root mean square radius (RMS radius) of visible light of different wavelengths at each field of view position of this wide-angle lens is less than 6.5μm, demonstrating that the wide-angle lens possesses low chromatic aberration and aberrations across the entire field of view, thus solving the purple fringing problem in visible light imaging and achieving high-resolution imaging.

[0144] The specific embodiments described above do not constitute a limitation on the scope of protection of this utility model. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. A wide-angle lens characterized by comprising: It includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens arranged sequentially along the optical axis from the object plane to the image plane; in the direction from the object plane to the image plane, The first lens is a convex-concave lens with negative optical power; The second lens is a convex-concave lens with negative optical power; The third lens has positive optical power; The fourth lens is a biconvex lens with positive optical power; Alternatively, the fourth lens may be a concave-convex lens with negative optical power; The fifth lens is a biconvex lens with positive optical power; The sixth lens is a biconcave lens with negative optical power; The seventh lens is a biconvex lens with positive optical power; The eighth lens is a convex-concave lens in the paraxial region and a concave-convex lens in the off-axis region, and has negative optical power; The sixth lens and the seventh lens together form a cemented lens.

2. The wide-angle lens of claim 1, wherein The first lens is a glass spherical lens; The second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, and the eighth lens are all plastic aspherical lenses.

3. The wide-angle lens of claim 2, wherein The third lens is either a biconvex lens or a biconcave lens.

4. The wide-angle lens of claim 1, wherein The optical power of the wide-angle lens is φ, the optical power of the first lens is φ1, the optical power of the second lens is φ2, the optical power of the third lens is φ3, the optical power of the fourth lens is φ4, the optical power of the fifth lens is φ5, the optical power of the sixth lens is φ6, the optical power of the seventh lens is φ7, the optical power of the cemented lens is φ67, and the optical power of the eighth lens is φ8, wherein: -0.34<φ1 / φ<-0.18; -0.41<φ2 / φ<-0.20; 0.03<φ3 / φ<0.3; -0.04<φ4 / φ<0.33; 0.41<φ5 / φ<0.54; -0.92<φ6 / φ<0.69; 0.72<φ7 / φ<1.04; -0.54<φ8 / φ<-0.2; 0.017<φ67 / φ<0.

36.

5. The wide-angle lens according to claim 1, characterized in that, The Abbe number of the sixth lens is vd6, the Abbe number of the seventh lens is vd7, the combined focal length of the sixth and seventh lenses is F67, and the focal length of the wide-angle lens is F, wherein: 20.7≤|vd7-vd6|≤36.5; 2≤F67 / F≤57.

6. The wide-angle lens of claim 1, wherein The refractive index of the third lens is nd3, and the Abbe number of the third lens is vd3, wherein: 1.8 <nd3<2;22<vd3<26。 7. The wide-angle lens of claim 1, wherein The entrance pupil diameter of the wide-angle lens is EPD, and the focal length of the wide-angle lens is F, wherein: F / EPD≤1.

85.

8. The wide-angle lens of claim 1, wherein, The distance from the center of the optical axis on the image side of the eighth lens to the image plane is BFL, the distance from the center of the optical axis on the object side of the first lens to the image plane is TTL, and the focal length of the wide-angle lens is F, wherein: TTL / F < 8; BFL / F > 0.

08.

9. The wide-angle lens of claim 1, wherein, The wide-angle lens also includes an aperture stop; The aperture stop is located in the optical path between the fourth lens and the fifth lens.

10. The wide-angle lens of claim 9, wherein, The focal length of the fourth lens is F4, the focal length of the fifth lens is F5, and the focal length of the wide-angle lens is F, wherein: -23 < (F4 + F5) / F < 7.

Images