Optical lens

Abstract

The utility model discloses an optical lens comprising 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. The focal power of the first lens is negative and is phi 1, the focal power of the second lens is negative, the third lens has focal power, the focal power of the fourth lens is positive and is phi 4, the focal power of the fifth lens is positive and is phi 5, and the focal power of the sixth lens is negative and is phi 6. The focal power of the seventh lens is positive and phi 7, the focal power of the eighth lens is negative, and the focal power of the optical lens is phi; wherein-0.556 < = phi 1 / phi < =-0.392, 0.330 < = phi 4 / phi < = 0.541, 0.374 < = phi 5 / phi < = 0.504,-0.664 < = phi 6 / phi < =-0.465, and 0.458 < = phi 7 / phi < = 0.582. According to the technical scheme, the number of the lenses and the focal power matching mode of the lenses are reasonably set, so that the design of the large-aperture, large-target-surface and high-pixel optical lens can be realized.

Description

Technical Field

[0001] This utility model relates to the field of optical device technology, and in particular to an optical lens. Background Technology

[0002] With industry development, market expansion, and varying demands, lenses with different focal lengths, apertures, angles, and image heights have emerged. Among them, large-aperture lenses hold a significant place due to their ability to produce detailed images. Currently, mainstream large-aperture lenses achieve parameters up to F1.0, utilize a large number of glass lenses, and are paired with a 1 / 2.7″ sensor. However, as the industry evolves, low-cost, high-resolution, high-pixel lenses are becoming the mainstream development trend. Therefore, developing a low-cost lens with a large aperture, large sensor size, and high pixel count is essential. Utility Model Content

[0003] This invention provides an optical lens that achieves a design with a large aperture, large lens surface, and high pixel count.

[0004] This utility model embodiment provides an optical lens, including 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;

[0005] The first lens has a negative optical power and an optical power of The second lens has a negative optical power, the third lens has an optical power, and the fourth lens has a positive optical power and an optical power of [missing value]. The optical power of the fifth lens is positive and the optical power is [value missing]. The sixth lens has a negative optical power and an optical power of [value missing]. The optical power of the seventh lens is positive and the optical power is [value missing]. The optical power of the eighth lens is negative, and the optical power of the optical lens is [missing value].

[0006] in,

[0007]

[0008] Optionally, the combined optical power of the first lens and the second lens is: The combined optical power of the third and fourth lenses is: The combined optical power of the fifth lens, the sixth lens, and the seventh lens is: The optical power of the eighth lens is:

[0009] in,

[0010] Optionally, the center thickness of the second lens is THIC2, the edge thickness of the second lens is MNEG2, the radius of curvature of the object plane side of the second lens is R12, and the radius of curvature of the image plane side of the second lens is R22.

[0011] Among them, 0.802≤MNEG2 / THIC2≤1.143, 0.865≤R12 / R22≤1.140.

[0012] Optionally, the sagitta at the object-side half-aperture of the eighth lens is SAG1. 8-0.5D The sagittal height at the full aperture of the eighth lens on the object side is SAG1. 8-1D The center thickness of the eighth lens is THIC8, and the edge thickness of the eighth lens is MNEG8.

[0013] Where, -1.621≤SAG1 8-0.5D / SAG1 8-1D ≤-0.614;

[0014] 1.250≤MNEG8 / THIC8≤1.822.

[0015] Optionally, the Abbe number of the first lens is vd1 and the Abbe number of the second lens is vd2;

[0016] Among them, 35.15≤vd1≤71.50, 18.00≤vd2≤28.35.

[0017] Optionally, the optical system further includes an aperture stop that coincides with the object-side surface of the third lens;

[0018] The Abbe number of the third lens is vd3, the refractive index of the fourth lens is nd4, and the Abbe number of the fourth lens is vd4.

[0019] Among them, 18.00≤vd3≤41.21, 1.450≤nd4≤1.700, 44.36≤vd4≤95.17.

[0020] Optionally, the Abbe number of the fifth lens is vd5, the refractive index of the sixth lens is nd6, the Abbe number of the sixth lens is vd6, and the Abbe number of the seventh lens is vd7.

[0021] Among them, 49.50≤vd5≤84.19, 1.520≤nd6≤1.700, 18.09≤vd6≤26.35, and 37.80≤vd7≤75.24.

[0022] Optionally, the first lens and the fourth lens include glass spherical lenses, and the second lens, the third lens, the fifth lens, the sixth lens, the seventh lens, and the eighth lens include plastic aspherical lenses.

[0023] Optionally, the first lens includes a first object-side surface near the object surface and a first image-side surface near the image surface. The first object-side surface is a plane, a convex surface, or a concave surface, and the first image-side surface is a concave surface.

[0024] The second lens includes a second object-side surface near the object plane and a second image-side surface near the image plane. The second object-side surface is concave, and the second image-side surface is convex.

[0025] The third lens includes a third object-side surface near the object plane and a third image-side surface near the image plane. The third object-side surface is convex, and the third image-side surface is concave.

[0026] The fourth lens includes a fourth object-side surface near the object plane and a fourth image-side surface near the image plane. The fourth object-side surface is convex, and the fourth image-side surface is convex.

[0027] The fifth lens includes a fifth object-side surface near the object plane and a fifth image-side surface near the image plane. The fifth object-side surface is convex, and the fifth image-side surface is convex.

[0028] The sixth lens includes a sixth object-side surface near the object plane and a sixth image-side surface near the image plane. The sixth object-side surface is concave, and the sixth image-side surface is concave.

[0029] The seventh lens includes a seventh object-side surface near the object plane and a seventh image-side surface near the image plane. The seventh object-side surface is convex, and the seventh image-side surface is convex.

[0030] The eighth lens includes an eighth object-side surface near the object plane and an eighth image-side surface near the image plane. The eighth object-side surface is convex, and the eighth image-side surface is concave.

[0031] Optionally, the aperture of the optical lens is F, and the total optical length is TTL;

[0032] Where F≥1.1, TTL<50mm.

[0033] The optical lens provided in this embodiment includes eight lenses with optical power, and the optical power of the eight lenses is distributed in a negative-negative-positive-positive-positive-negative-positive-negative manner, or in a negative-negative-negative-positive-positive-negative-positive-negative manner. By reasonably setting the number of lenses and the optical power combination of the lenses, it is possible to ensure small imaging aberrations and high imaging quality while maintaining the miniaturization of the optical system. Furthermore, the optical power of the first lens... The optical power of the fourth lens The optical power of the fifth lens The optical power of the sixth lens The optical power of the seventh lens and the optical focal length of the lens satisfy By using a suitable optical power ratio, an optical system can achieve the characteristics of a large aperture and a large target surface.

[0034] 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

[0035] 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.

[0036] Figure 1 This is a schematic diagram of the structure of an optical lens provided in Embodiment 1 of this utility model;

[0037] Figure 2 This is a chromatic aberration curve of an optical lens provided in Embodiment 1 of this utility model;

[0038] Figure 3 A transverse chromatic aberration diagram of an optical lens provided in Embodiment 1 of this utility model;

[0039] Figure 4 This is a schematic diagram of the structure of an optical lens provided in Embodiment 2 of this utility model;

[0040] Figure 5 This is a chromatic aberration curve of an optical lens provided in Embodiment 2 of this utility model;

[0041] Figure 6 A transverse chromatic aberration diagram of an optical lens provided in Embodiment 2 of this utility model;

[0042] Figure 7 This is a schematic diagram of the structure of an optical lens provided in Embodiment 3 of this utility model;

[0043] Figure 8 This is a chromatic aberration curve of an optical lens provided in Embodiment 3 of this utility model;

[0044] Figure 9 This is a transverse chromatic aberration diagram of an optical lens provided in Embodiment 3 of this utility model. Detailed Implementation

[0045] 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.

[0046] Example 1

[0047] Figure 1 This is a schematic diagram of the structure of an optical lens provided in Embodiment 1 of this utility model, as shown below. Figure 1 As shown, the optical lens provided in this embodiment of the present invention includes a first lens 101, a second lens 102, a third lens 103, a fourth lens 104, a fifth lens 105, a sixth lens 106, a seventh lens 107, and an eighth lens 108 arranged sequentially along the optical axis from the object plane to the image plane; the first lens has a negative optical power and an optical power of [missing value]. The second lens has a negative optical power, the third lens has an optical power, and the fourth lens has a positive optical power and an optical power of [missing value]. The optical power of the fifth lens is positive and the optical power is [value missing]. The sixth lens has a negative optical power and an optical power of [value missing]. The optical power of the seventh lens is positive and the optical power is [value missing]. The optical power of the eighth lens is negative, and the optical power of the optical lens is [missing value]. in,

[0048]

[0049] Specifically, the optical lens provided in this embodiment includes eight lenses with optical power: a first lens 101, a second lens 102, a third lens 103, a fourth lens 104, a fifth lens 105, a sixth lens 106, a seventh lens 107, and an eighth lens 108. The arrangement of eight lenses ensures that the number of lenses in the optical system is reasonable. Too many lenses will result in a large lens size, and too few lenses will result in a large aberration due to a single lens bearing a large optical power. This ensures that the optical system is miniaturized while maintaining small imaging aberrations and high imaging quality.

[0050] Furthermore, optical power is equal to the difference between the convergence of the beam at the image plane and the convergence of the beam at the object plane; it characterizes the ability of an optical system to deflect light rays. The larger the absolute value of the optical power, the stronger its ability to bend light rays; the smaller the absolute value, the weaker its ability to bend light rays. When the optical power is positive, the refraction of light rays is converging; when the optical power is negative, the refraction of light rays 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).

[0051] In this embodiment of the present invention, the first lens 101 and the second lens 102 are both negative power lenses. As the first lenses in the optical lens that adjust the incident light first, the negative power setting of the first lens 101 and the second lens 102 can ensure that the light has a larger aperture before entering the aperture stop, thereby increasing the aperture of the optical lens and enabling the lens to still form a clear image under dim or dark conditions.

[0052] The third lens 103 has optical power, and it can be either a positive or negative optical power lens. When the third lens 103 is a positive optical power lens, combined with the positive optical power design of the fourth lens 104, the third lens 103 and the fourth lens 104 can promptly correct the large aberrations produced by the first lens 101 and the second lens 102, especially effectively correcting the edge aberrations of the optical lens, thereby improving the imaging resolution of the optical system. When the third lens 103 is a negative optical power lens, its combination with the negative optical power design of the first lens 101 and the second lens 102 can further increase the aperture of the optical lens, enabling the lens to still produce clear images in dim or dark conditions. Furthermore, the positive optical power fourth lens 104 can promptly correct the large aberrations produced by the first lens 101, the second lens 102, and the third lens 103, ensuring the resolution of large-aperture imaging.

[0053] Furthermore, the fifth lens 105 is a positive power lens, the sixth lens 106 is a negative power lens, the seventh lens 107 is a positive power lens, and the eighth lens 108 is a negative power lens. The fifth lens 105, the sixth lens 106, the seventh lens 107, and the eighth lens 108 adopt a positive-negative-positive-negative combination. The power of each subsequent lens in the optical path is different from that of the previous lens, which is beneficial for aberration correction.

[0054] Furthermore, the optical power of the first lens 101 The fourth lens has an optical power of 104. The fifth lens has an optical power of 105. The sixth lens has an optical power of 106. The seventh lens has an optical power of 107. and the optical focal length of the lens satisfy A suitable optical power value can not only improve the aberration of a single lens, optimize the system tolerance, reduce the contribution of a single lens to the system tolerance sensitivity, and reduce the manufacturing cost of the optical system, but also enable the optical system to achieve the characteristics of a large aperture and a large target surface through a suitable optical power ratio. In the optical system provided by this utility model embodiment, the aperture can reach 1.1, which can be used with a 1 / 1.2″ large target surface.

[0055] In summary, the optical lens provided by this embodiment of the invention, through a reasonable setting of the number of lenses and the matching of their optical power, can ensure both miniaturization of the optical system and low imaging aberrations, as well as high imaging quality. Furthermore, by using a suitable optical power ratio, the optical system can achieve the characteristics of a large aperture and a large target surface.

[0056] Further reference Figure 1 As shown, the optical lens provided in this embodiment of the present invention may further include a filter 109, which is disposed in the optical path between the eighth lens 108 and the image plane to filter out stray light and improve the imaging effect.

[0057] Furthermore, the optical lens provided in this embodiment may also include a protective glass and an imaging sensor. The protective glass can be disposed on the image-side of the filter, and the image acquisition element can be disposed on the image-side of the protective glass. The optical system is protected by the protective glass, and the image is acquired by the imaging sensor, thus enabling the optical system to perform its normal imaging function.

[0058] Based on the above embodiments, the combined optical power of the first lens 101 and the second lens 102 is: The combined optical power of the third lens 103 and the fourth lens 104 is: The combined optical power of the fifth lens 105, the sixth lens 106, and the seventh lens 107 is: The optical power of the eighth lens 108 is in,

[0059] Specifically, the combined optical power of the first lens 101 and the second lens 102 Optical power of the eighth lens 108 Between In other words, the combined optical power of the first lens 101 and the second lens 102 located at the front of the optical lens is similar to the optical power of the eighth lens 108 located at the rear of the optical lens. The combined optical power of the third lens 103 and the fourth lens 104... Combined optical power with the fifth lens 105, the sixth lens 106 and the seventh lens 107 Between In other words, the combined optical power of the third lens 103 and the fourth lens 104, located in the middle of the optical lens, is similar to that of the combined optical power of the fifth lens 105, the sixth lens 106, and the seventh lens 107. The symmetrical and similar optical power characteristics of the system are more conducive to the optimization of system aberrations, improving the overall resolution of the system, and realizing the high resolution characteristics of a large aperture system.

[0060] Based on the above embodiments, the second lens 102 includes an aspherical lens; the center thickness of the second lens 102 is THIC2, the edge thickness of the second lens 102 is MNEG2, the radius of curvature on the object plane side of the second lens 102 is R12, and the radius of curvature on the image plane side of the second lens 102 is R22; wherein, 0.802≤MNEG2 / THIC2≤1.143, 0.865≤R12 / R22≤1.140.

[0061] 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 better radius of curvature characteristics, which improves distortion and astigmatism. Therefore, setting the second lens 102 as an aspherical lens can improve distortion and astigmatism. Furthermore, by controlling the degree of concentric ring structure of the second lens 102 by adjusting the ratio of its edge thickness to its center thickness and the ratio of its object-side radius of curvature to its image-side radius of curvature, the concentric ring structure of the second lens 102, combined with its aspherical surface shape, can better adjust the optical path difference in each field of view, which is beneficial for optimizing coma and astigmatism in off-axis fields of view.

[0062] Based on the above embodiments, the eighth lens 108 includes an aspherical lens; the sagitta at the object-side half-aperture of the eighth lens 108 is SAG1.8-0.5D The sagitta at the full aperture of the eighth lens 108 on the object plane side is SAG1. 8-1D The center thickness of the eighth lens 108 is THIC8, and the edge thickness of the eighth lens 108 is MNEG8; where -1.621≤SAG1 8-0.5D / SAG1 8-1D ≤-0.614; 1.250≤MNEG8 / THIC8≤1.822.

[0063] Specifically, setting the eighth lens 108 as an aspherical lens can improve distortion aberration and astigmatism. Furthermore, the concentricity and asphericity of the eighth lens 108 are described by the ratio of its half-aperture to its full-aperture on the object side and the ratio of its edge thickness to its center thickness. Adjusting the optical path difference across the system's fields of view helps improve the field curvature of the system's outer field of view. Simultaneously, compared to the first lens 101 and the second lens 102, the eighth lens 108, by controlling its own asphericity, not only achieves an optical power similar to the combined optical power of the first lens 101 and the second lens 102, but also improves the system's resolution. Achieving the optical characteristics of two lenses with a single lens helps reduce system costs.

[0064] Based on the above embodiments, the Abbe number of the first lens 101 is vd1 and the Abbe number of the second lens 102 is vd2; wherein, 35.15≤vd1≤71.50, 18.00≤vd2≤28.35.

[0065] Specifically, the Abbe number is an index used to represent the dispersion ability of a transparent medium. The more severe the dispersion of the medium, the smaller the Abbe number; conversely, the less severe the dispersion of the medium, the larger the Abbe number. By properly setting the Abbe number of the first lens 101 and the second lens 102, chromatic aberration caused by light entering the optical system at different angles can be reduced.

[0066] Based on the above embodiments, the optical system further includes an aperture stop (not shown in the figure), which coincides with the object side surface of the third lens 103; the Abbe number of the third lens 103 is vd3, the refractive index of the fourth lens 104 is nd4, and the Abbe number of the fourth lens 104 is vd4; wherein, 18.00≤vd3≤41.21, 1.450≤nd4≤1.700, and 44.36≤vd4≤95.17.

[0067] Specifically, the optical lens provided in this embodiment may further include an aperture stop. Setting an aperture stop can adjust the propagation direction of the light beam, which is beneficial to improving image quality. Furthermore, the aperture stop may coincide with the object side of the third lens 103, that is, the aperture stop 107 is set in the optical system, which is beneficial to reduce the aperture value and achieve a large aperture.

[0068] Refractive index is the ratio of the speed of light in a vacuum to the speed of light in a medium, used to describe a material's ability to refract light; different materials have different refractive indices. In this embodiment of the invention, the use of third lens 103 and fourth lens 104, made of materials with appropriate refractive indices and Abbe numbers near the aperture stop, can effectively reduce the transverse chromatic aberration of the system, thereby reducing the impact of transverse chromatic aberration on light rays at different angles and improving resolution in different fields of view.

[0069] Based on the above embodiment, the Abbe number of the fifth lens 105 is vd5, the refractive index of the sixth lens 106 is nd6, the Abbe number of the sixth lens 106 is vd6, and the Abbe number of the seventh lens 107 is vd7; wherein, 49.50≤vd5≤84.19, 1.520≤nd6≤1.700, 18.09≤vd6≤26.35, and 37.80≤vd7≤75.24. Using appropriate refractive index and Abbe number materials for the three lenses can effectively reduce chromatic aberration in the optical system, which is beneficial for improving the resolution of the on-axis field of view. It also has a certain improvement effect on the transverse chromatic aberration of the off-axis field of view, enabling the large aperture system to achieve high resolution.

[0070] Based on the above embodiments, the first lens 101 and the fourth lens 104 include glass spherical lenses, and the second lens 102, the third lens 103, the fifth lens 105, the sixth lens 106, the seventh lens 107 and the eighth lens 108 include plastic aspherical lenses.

[0071] Specifically, spherical lenses are characterized by a constant curvature from the center to the periphery, ensuring a simple lens setup. Aspherical lenses, on the other hand, have a continuously changing curvature from the center to the periphery. Unlike spherical lenses with a constant curvature, aspherical lenses have superior curvature radius characteristics, offering advantages in improving distortion and astigmatism. Furthermore, due to the low coefficient of thermal expansion and good stability of glass lenses, both the first lens 101 and the fourth lens 10 are designed as glass spherical lenses. The thermal properties of glass spherical lenses are more stable, ensuring good resolving power over a wide temperature range when handling higher optical powers. Moreover, the wider range of glass materials available allows for more flexible selection of refractive index and Abbe number, enabling better control over higher aberrations and chromatic aberration, meeting the needs of use under complex conditions. Furthermore, the second lens 102, the third lens 103, the fifth lens 105, the sixth lens 106, the seventh lens 107, and the eighth lens 108 include plastic aspherical lenses. The inclusion of plastic aspherical lenses is beneficial for reducing the processing technology of aspherical lenses, and the cost of aspherical lenses is low, which can reduce the cost of the optical system.

[0072] Therefore, the optical lens provided in this embodiment of the present invention can adopt a combination of glass spherical lenses and plastic aspherical lenses, which can effectively control the cost of the optical lens while ensuring its optical performance; at the same time, the materials of each lens have a mutual compensating effect, which can ensure normal use in high and low temperature environments.

[0073] Based on the above embodiments, the first lens 101 includes a first object-side surface near the object plane and a first image-side surface near the image plane. The first object-side surface is planar, convex, or concave, and the first image-side surface is concave. The second lens 102 includes a second object-side surface near the object plane and a second image-side surface near the image plane. The second object-side surface is concave, and the second image-side surface is convex. The third lens 103 includes a third object-side surface near the object plane and a third image-side surface near the image plane. The third object-side surface is convex, and the third image-side surface is concave. The fourth lens 104 includes a fourth object-side surface near the object plane and a fourth image-side surface near the image plane. The fourth object-side surface is convex. The fourth image side is convex; the fifth lens 105 includes a fifth object side near the object plane and a fifth image side near the image plane, both of which are convex; the sixth lens 106 includes a sixth object side near the object plane and a sixth image side near the image plane, both of which are concave; the seventh lens 107 includes a seventh object side near the object plane and a seventh image side near the image plane, both of which are convex; the eighth lens 108 includes an eighth object side near the object plane and an eighth image side near the image plane, both of which are convex.

[0074] Specifically, the object-side surface of a lens can be understood as the surface of the lens closest to the object plane, and the image-side surface of a lens can be understood as the surface of the lens closest to the image plane. The object-side surface of the first lens 101 is planar, convex, or concave, and the image-side surface is concave. This can be understood as the object-side surface of the first lens 101 being convex or concave towards the object plane near the optical axis, or the object-side surface of the first lens 101 being planar, convex-concave, or biconcave lens. Figure 1The following explanation uses a first lens 101 with a plano-concave structure as an example. The first lens 101 can be a negative power lens. The surface shape of the first lens 101, combined with its power parameters, can converge light rays into the system from a wide field of view, thus improving the field of view of the optical system. The second lens 102 has a concave object-side surface and a convex image-side surface. This can be understood as the object-side surface of the second lens 102 being concave towards the object plane near the optical axis, and the image-side surface being convex towards the image plane near the optical axis; that is, the second lens 102 is a concave-convex structure lens. The second lens 102 is designed as a concave-convex negative power lens. The third lens 103 has a convex object-side surface and a concave image-side surface. This can be understood as the object-side surface of the third lens 103 being convex towards the object plane near the optical axis, and the image-side surface being concave towards the image plane near the optical axis; that is, the third lens 103 is a convex-concave structure lens. The fourth lens 104 has a convex object-side surface and a convex image-side surface. This can be understood as the object-side surface of the fourth lens 104 bulging towards the object plane near the optical axis, and the image-side surface bulging towards the image plane near the optical axis. Therefore, the fourth lens 140 is a biconvex lens. The fifth lens 105 also has a convex object-side surface and a convex image-side surface. This can be understood as the object-side surface of the fifth lens 105 bulging towards the object plane near the optical axis, and the image-side surface bulging towards the image plane near the optical axis. Therefore, the fifth lens 105 is a biconvex lens. The sixth lens 106 has a concave object-side surface and a convex image-side surface. This can be understood as the object-side surface of the sixth lens 106 being concave towards the object plane near the optical axis, and the image-side surface being concave towards the image plane near the optical axis. Therefore, the sixth lens 106 is a biconcave lens. The seventh lens 107 has a convex object-side surface and a convex image-side surface. This can be understood as the object-side surface of the seventh lens 107 bulging towards the object plane near the optical axis, and the image-side surface bulging towards the image plane near the optical axis, making the seventh lens 107 a biconvex lens. Similarly, the eighth lens 108 has a convex object-side surface and a concave image-side surface. This can be understood as the object-side surface of the eighth lens 108 bulging towards the object plane near the optical axis, and the image-side surface concave towards the image plane near the optical axis, making the eighth lens 108 a convex-concave lens. In summary, by appropriately setting the convex and concave surface shapes of each lens, combined with the optical power settings of each lens, it is beneficial to correct spherical aberration, aberrations, and field curvature, thereby improving imaging quality.

[0075] Based on the above embodiments, the aperture of the optical lens is F, and the total optical length is TTL; wherein, F≥1.1, TTL<50mm, thus realizing a fixed-focus optical lens with a large aperture and a small size.

[0076] As one feasible implementation method, the specific parameters of the optical lens are explained below.

[0077] Table 1. Optical design values ​​for the optical lens in Example 1.

[0078]

[0079] Table 2 Design values ​​of optical physical parameters of optical lenses

[0080] Face number Surface type radius of curvature thickness nd vd / dPg,F Half diameter k S1 spherical Infinity 0.955 1.875 39.06 / 0.027 8.588 S2 spherical 12.786 6.105 7.098 S3 aspherical -8.029 3.605 1.522 25.07 / -0.010 6.620 -0.485 S4 aspherical -8.245 3.832 7.290 -1.808 S5 (STO) aspherical 29.134 4.555 1.559 20.50 / -0.010 7.226 -4.126 S6 aspherical 26.007 0.265 7.074 -0.855 S7 spherical 15.806 7.036 1.468 49.28 / 0.050 7.303 S8 spherical -19.922 0.055 7.303 S9 aspherical 17.319 6.060 1.686 65.17 / 0.050 6.867 -2.569 S10 aspherical -26.028 0.251 6.371 4.990 S11 aspherical -10.036 2.223 1.577 20.10 / -0.010 6.118 -7.548 S12 aspherical 51.459 0.697 6.015 -138.624 S13 aspherical 20.558 5.613 1.662 68.39 / 0.044 6.393 1.854 S14 aspherical -15.999 0.196 5.812 -4.059 S15 aspherical 9.795 1.247 1.535 2.10 / 0.050 5.785 -16.040 S16 aspherical 5.994 2.400 6.146 -5.960 S17 spherical Infinity 0.600 1.517 64.20 / -0.001 6.322 S18 spherical Infinity Focus as needed 6.361

[0081] The surface numbers in Table 2 are assigned according to the surface sequence of each lens. For example, surface number "S1" represents the object plane side of the first lens, surface number "S2" represents the image plane side 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 means that the surface bends towards the object plane with the center closer to the image plane, and a negative value means that the surface bends towards the image plane with the center closer to the object plane. "Infinity" means that the surface is flat and the radius of curvature is infinite. The thickness represents the central axial distance between the current surface and the next surface. Since the different number of digits of each parameter value can cause focusing errors, the thickness of surface 18 is not given a specific value. The value can be adjusted as needed to achieve a clear focus. 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 and the refractive index is 1. 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. dPgF represents the relative partial dispersion of the material. Half-diameter refers to half the diameter of the lens.

[0082] The formula for aspherical surfaces is shown below:

[0083]

[0084] Where Z is the aspherical elevation, c is the fundamental curvature at the vertex, k is the conic section constant, r is the radial coordinate perpendicular to the optical axis, and a i a is the coefficient of the higher-order term. i r 2i For aspherical surfaces, the term is of higher order.

[0085] Table 3. Design values ​​for the aspherical coefficient of optical lenses.

[0086]

[0087] Where 1.408E-04 represents 1.408 * 10 -4 All other parameters can be represented in this way.

[0088] Table 4 Specific parameters for this embodiment

[0089] Focal length (mm) 7.342 Aperture F 1.104 Field of view 108° Total lens length (mm) 48.053

[0090] Figure 2This is a chromatic aberration curve of an optical lens according to Embodiment 1 of this utility model. The vertical direction represents the normalized 0-field pupil plane, where 0 represents the pupil center, and the vertical vertex represents the pupil vertex. The horizontal direction represents the axial chromatic aberration at different wavelengths (436nm, 486nm, 546nm, 587nm, and 656nm), in millimeters (mm). As shown in the figure, the system's axial chromatic aberration is within ±0.05mm, indicating that the system's chromatic aberration correction is good.

[0091] Figure 3 This is a transverse chromatic aberration diagram of an optical lens provided in Embodiment 1 of this utility model. In the diagram, the vertical direction represents the field of view angle, with 0 representing the field of view angle incident parallel to the optical axis, and the vertical vertex representing the maximum half-field of view angle. The horizontal direction represents the offset within a meridian range of 0.546 μm, in micrometers (μm). The numbers on the curves in the diagram represent the wavelengths represented by those curves, in micrometers (μm). As shown in the diagram, the transverse chromatic aberration of each wavelength in the system is within ±10 μm, indicating good chromatic aberration correction. As the angle increases, the transverse chromatic aberrations of each wavelength overlap, indicating that the system has a certain degree of chromatic aberration correction for each field of view.

[0092] In summary, the optical lens provided by this utility model embodiment uses two glass lenses combined with six plastic lenses. By reasonably setting the optical parameters of each lens and the optical parameters of the optical lens, an optical lens with the characteristics of large aperture, low cost, large target surface and high pixel count is achieved. The large aperture lens can reach an aperture of 1.1 and can be used with a 1 / 1.2″ large target surface.

[0093] Example 2

[0094] Figure 4 This is a schematic diagram of the structure of an optical lens provided in Embodiment 2 of this utility model, as shown below. Figure 4 As shown, the optical lens provided in this embodiment of the present invention includes a first lens 101, a second lens 102, a third lens 103, a fourth lens 104, a fifth lens 105, a sixth lens 106, a seventh lens 107, and an eighth lens 108 arranged sequentially along the optical axis from the object plane to the image plane; the first lens has a negative optical power and an optical power of [missing value]. The second lens has a negative optical power, the third lens has an optical power, and the fourth lens has a positive optical power and an optical power of [missing value]. The optical power of the fifth lens is positive and the optical power is [value missing]. The sixth lens has a negative optical power and an optical power of [value missing]. The optical power of the seventh lens is positive and the optical power is [value missing]. The optical power of the eighth lens is negative, and the optical power of the optical lens is [missing value]. in,

[0095] The structural difference between Embodiment 2 and Embodiment 1 is that the object side of the first lens is convex.

[0096] As another feasible implementation method, the specific parameters of the optical lens are explained below.

[0097] Table 5. Optical design values ​​for the optical lens in Example 2.

[0098]

[0099] Table 6 Design values ​​of optical physical parameters for optical lenses

[0100] Face number Surface type radius of curvature thickness nd vd / dPg,F Half diameter k S1 spherical 50.000 0.955 1.589 64.20 / 0.004 9.917 S2 spherical 8.243 7.210 7.169 S3 aspherical -8.074 3.272 1.643 25.77 / -0.010 6.944 -0.618 S4 aspherical -8.383 5.001 7.170 -1.936 S5 (STO) aspherical 37.140 3.251 1.661 37.46 / -0.009 7.263 -9.415 S6 aspherical 18.636 0.665 7.128 0.459 S7 spherical 17.483 6.541 1.593 67.12 / 0.050 7.352 S8 spherical -15.529 0.400 7.550 S9 aspherical 15.373 5.901 1.547 76.54 / 0.050 6.814 -3.382 S10 aspherical -21.784 0.257 6.080 6.272 S11 aspherical -9.735 1.976 1.637 23.45 / -0.011 6.150 -7.603 S12 aspherical 48.723 0.635 5.858 -42.071 S13 aspherical 21.371 5.039 1.554 59.43 / 0.050 6.068 3.509 S14 aspherical -11.272 0.103 5.896 -4.688 S15 aspherical 9.988 1.426 1.532 55.71 / -0.010 5.881 -13.787 S16 aspherical 6.288 2.400 6.200 -5.535 S17 spherical Infinity 0.600 1.517 64.20 / -0.001 6.527 S18 spherical Infinity Focus as needed 6.560

[0101] The surface numbers in Table 6 are assigned according to the surface sequence of each lens. For example, surface number "S1" represents the object plane side of the first lens, surface number "S2" represents the image plane side 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 means that the surface bends towards the object plane with the center closer to the image plane, and a negative value means that the surface bends towards the image plane with the center closer to the object plane. "Infinity" means 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. Since the different number of digits of each parameter value can cause focusing errors, the thickness of surface 18 is not given a specific value. The value can be adjusted as needed to achieve a clear focus. 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 and the refractive index is 1. 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. dPgF represents the relative partial dispersion of the material. Half-diameter refers to half the diameter of the lens.

[0102] The formula for aspherical surfaces is shown below:

[0103]

[0104] Where Z is the aspherical elevation, c is the fundamental curvature at the vertex, k is the conic section constant, r is the radial coordinate perpendicular to the optical axis, and a i a is the coefficient of the higher-order term. i r 2i For aspherical surfaces, the term is of higher order.

[0105] Table 7. Design values ​​for the aspherical coefficient of optical lenses.

[0106]

[0107] Where 2.412E-04 represents 2.412 * 10 -4 All other parameters can be represented in this way.

[0108] Table 8 Specific parameters for this embodiment

[0109] Focal length (mm) 7.342 Aperture F 1.103 Field of view 105° Total lens length (mm) 47.989

[0110] Figure 5 This is a chromatic aberration curve of an optical lens provided in Embodiment 2 of this utility model. The vertical direction in the figure represents the normalized 0-field pupil plane, where 0 represents the pupil center, and the vertical vertex represents the pupil vertex. The horizontal direction represents the axial chromatic aberration at different wavelengths (436nm, 486nm, 546nm, 587nm, and 656nm), in millimeters (mm). As shown in the figure, the system's axial chromatic aberration is within ±0.05mm, indicating that the system's chromatic aberration correction is good.

[0111] Figure 6 This is a transverse chromatic aberration diagram of an optical lens provided in Embodiment 2 of this utility model. In the diagram, the vertical direction represents the field of view angle, with 0 representing the field of view angle incident parallel to the optical axis, and the vertical vertex representing the maximum half-field of view angle. The horizontal direction represents the offset within a meridian range based on 0.546 μm, in micrometers (μm). The numbers on the curves in the diagram represent the wavelengths represented by those curves, in micrometers (μm). As shown in the diagram, the transverse chromatic aberration of each wavelength in the system is within ±10 μm, indicating that the system has good chromatic aberration correction. As the angle increases, the transverse chromatic aberrations of each wavelength overlap, indicating that the system has a certain degree of chromatic aberration correction for each field of view.

[0112] In summary, the optical lens provided by this utility model embodiment uses two glass lenses combined with six plastic lenses. By reasonably setting the optical parameters of each lens and the optical parameters of the optical lens, an optical lens with the characteristics of large aperture, low cost, large target surface and high pixel count is achieved. The large aperture lens can reach an aperture of 1.1 and can be used with a 1 / 1.2″ large target surface.

[0113] Example 3

[0114] Figure 7 This is a schematic diagram of the structure of an optical lens provided in Embodiment 3 of this utility model, as shown below. Figure 7 As shown, the optical lens provided in this embodiment of the present invention includes a first lens 101, a second lens 102, a third lens 103, a fourth lens 104, a fifth lens 105, a sixth lens 106, a seventh lens 107, and an eighth lens 108 arranged sequentially along the optical axis from the object plane to the image plane; the first lens has a negative optical power and an optical power of [missing value]. The second lens has a negative optical power, the third lens has an optical power, and the fourth lens has a positive optical power and an optical power of [missing value]. The optical power of the fifth lens is positive and the optical power is [value missing]. The sixth lens has a negative optical power and an optical power of [value missing]. The optical power of the seventh lens is positive and the optical power is [value missing]. The optical power of the eighth lens is negative, and the optical power of the optical lens is [missing value]. in,

[0115] The structural difference between Embodiment 3 and Embodiment 1 is that the object-side surface of the first lens is concave.

[0116] As another feasible implementation method, the specific parameters of the optical lens are explained below.

[0117] Table 9. Optical design values ​​for the optical lens in Example 3.

[0118]

[0119] Table 10 Optical design values ​​of each lens in the optical lens

[0120] Face number Surface type radius of curvature thickness nd vd / dPg,F Half diameter k S1 spherical -154.936 0.840 1.530 65.00 / -0.010 9.421 S2 spherical 8.590 6.440 6.823 S3 aspherical -8.435 3.200 1.651 20.00 / 0.032 6.604 -0.606 S4 aspherical -8.138 5.051 7.096 -1.779 S5 (STO) aspherical 36.793 4.052 1.622 20.00 / -0.010 7.139 -9.188 S6 aspherical 19.338 0.654 6.889 0.412 S7 spherical 18.368 7.089 1.592 86.52 / 0.050 7.080 S8 spherical -15.126 0.599 7.314 S9 aspherical 15.409 5.873 1.540 55.00 / -0.010 6.609 -3.139 S10 aspherical -21.910 0.235 6.176 6.278 S11 aspherical -9.474 1.887 1.647 23.95 / -0.010 5.880 -7.288 S12 aspherical 53.563 0.557 5.646 -41.672 S13 aspherical 21.974 4.863 1.555 42.00 / 0.042 5.858 4.104 S14 aspherical -11.034 0.057 5.618 -5.360 S15 aspherical 10.101 1.271 1.490 55.71 / -0.010 5.642 -18.556 S16 aspherical 6.498 2.400 6.080 -7.223 S17 spherical Infinity 0.600 1.517 64.20 / -0.001 6.318 S18 spherical Infinity Focus as needed 6.359

[0121] The surface numbers in Table 10 are assigned according to the surface sequence of each lens. For example, surface number "S1" represents the object plane side of the first lens, surface number "S2" represents the image plane side 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 means that the surface bends towards the object plane with the center closer to the image plane, and a negative value means that the surface bends towards the image plane with the center closer to the object plane. "Infinity" means that the surface is flat and the radius of curvature is infinite. The thickness represents the central axial distance between the current surface and the next surface. Since the different number of digits of each parameter value can cause focusing errors, the thickness of surface 18 is not given a specific value. The value can be adjusted as needed to achieve a clear focus. 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 and the refractive index is 1. 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. dPgF represents the relative partial dispersion of the material. Half-diameter refers to half the diameter of the lens.

[0122] The formula for aspherical surfaces is shown below:

[0123]

[0124] Where Z is the aspherical elevation, c is the fundamental curvature at the vertex, k is the conic section constant, r is the radial coordinate perpendicular to the optical axis, and ai a is the coefficient of the higher-order term. i r 2i For aspherical surfaces, the term is of higher order.

[0125] Table 11 Design values ​​for the aspherical coefficient of an optical lens

[0126]

[0127] Wherein, 2.249E-04 represents 2.249 * 10 -4 All other parameters can be represented in this way.

[0128] Table 12 Specific parameters for this embodiment

[0129] Focal length (mm) 7.349 Aperture F 1.104 Field of view 108° Total lens length (mm) 48.030

[0130] Figure 8 This is a chromatic aberration curve of an optical lens provided in Embodiment 3 of this utility model. The vertical direction in the figure represents the normalized 0-field pupil plane, where 0 represents the pupil center, and the vertical vertex represents the pupil vertex. The horizontal direction represents the axial chromatic aberration at different wavelengths (436nm, 486nm, 546nm, 587nm, and 656nm), in millimeters (mm). As shown in the figure, the system's axial chromatic aberration is within ±0.05mm, indicating that the system's chromatic aberration correction is good.

[0131] Figure 9 This is a transverse chromatic aberration diagram of an optical lens provided in Embodiment 3 of this utility model. In the diagram, the vertical direction represents the field of view angle, with 0 representing the field of view angle incident parallel to the optical axis, and the vertical vertex representing the maximum half-field of view angle. The horizontal direction represents the offset within a meridian range based on 0.546 μm, in micrometers (μm). The numbers on the curves in the diagram represent the wavelengths represented by those curves, in micrometers (μm). As shown in the diagram, the transverse chromatic aberration of each wavelength in the system is within ±10 μm, indicating that the system has good chromatic aberration correction. As the angle increases, the transverse chromatic aberrations of each wavelength overlap, indicating that the system has a certain degree of chromatic aberration correction in each field of view.

[0132] In summary, the optical lens provided by this utility model embodiment uses two glass lenses combined with six plastic lenses. By reasonably setting the optical parameters of each lens and the optical parameters of the optical lens, an optical lens with the characteristics of large aperture, low cost, large target surface and high pixel count is achieved. The large aperture lens can reach an aperture of 1.1 and can be used with a 1 / 1.2″ large target surface.

[0133] 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. An optical lens, characterized in that 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; The first lens has a negative optical power and an optical power of The second lens has a negative optical power, the third lens has an optical power, and the fourth lens has a positive optical power and an optical power of [missing value]. The optical power of the fifth lens is positive and the optical power is [value missing]. The sixth lens has a negative optical power and an optical power of [value missing]. The optical power of the seventh lens is positive and the optical power is [value missing]. The optical power of the eighth lens is negative, and the optical power of the optical lens is [missing value]. wherein 2. The optical lens of claim 1, wherein, The combined optical power of the first lens and the second lens is The combined optical power of the third and fourth lenses is: The combined optical power of the fifth lens, the sixth lens, and the seventh lens is: The optical power of the eighth lens is: wherein 3. The optical lens of claim 1, wherein, The second lens includes an aspherical lens; The center thickness of the second lens is THIC2, the edge thickness of the second lens is MNEG2, the radius of curvature of the object plane side of the second lens is R12, and the radius of curvature of the image plane side of the second lens is R22. Among them, 0.802≤MNEG2 / THIC2≤1.143, 0.865≤R12 / R22≤1.

140.

4. The optical lens of claim 1, wherein, The eighth lens includes an aspherical lens; The sagitta at the half-aperture of the object plane side of the eighth lens is SAG1. 8-0.5D The sagittal height at the full aperture of the eighth lens on the object side is SAG1. 8-1D The center thickness of the eighth lens is THIC8, and the edge thickness of the eighth lens is MNEG8. wherein -1.621 < SAG1 8-0.5D / SAG1 8-1D ≤ -0.614; 1.250≤MNEG8 / THIC8≤1.

822.

5. The optical lens of claim 1, wherein, The Abbe number of the first lens is vd1, and the Abbe number of the second lens is vd2; Among them, 35.15≤vd1≤71.50, 18.00≤vd2≤28.

35.

6. The optical lens of claim 1, wherein, The optical lens also includes an aperture stop, which coincides with the object side surface of the third lens; The Abbe number of the third lens is vd3, the refractive index of the fourth lens is nd4, and the Abbe number of the fourth lens is vd4. Among them, 18.00≤vd3≤41.21, 1.450≤nd4≤1.700, 44.36≤vd4≤95.

17.

7. The optical lens of claim 1, wherein, The Abbe number of the fifth lens is vd5, the refractive index of the sixth lens is nd6, the Abbe number of the sixth lens is vd6, and the Abbe number of the seventh lens is vd7. Among them, 49.50≤vd5≤84.19, 1.520≤nd6≤1.700, 18.09≤vd6≤26.35, and 37.80≤vd7≤75.

24.

8. The optical lens of claim 1, wherein, The first lens and the fourth lens are glass spherical lenses, and the second lens, the third lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens are plastic aspherical lenses.

9. The optical lens of claim 1, wherein, The first lens includes a first object-side surface near the object surface and a first image-side surface near the image surface. The first object-side surface is a plane, a convex surface, or a concave surface, and the first image-side surface is a concave surface. The second lens includes a second object-side surface near the object plane and a second image-side surface near the image plane. The second object-side surface is concave, and the second image-side surface is convex. The third lens includes a third object-side surface near the object plane and a third image-side surface near the image plane. The third object-side surface is convex, and the third image-side surface is concave. The fourth lens includes a fourth object-side surface near the object plane and a fourth image-side surface near the image plane. The fourth object-side surface is convex, and the fourth image-side surface is convex. The fifth lens includes a fifth object-side surface near the object plane and a fifth image-side surface near the image plane. The fifth object-side surface is convex, and the fifth image-side surface is convex. The sixth lens includes a sixth object-side surface near the object plane and a sixth image-side surface near the image plane. The sixth object-side surface is concave, and the sixth image-side surface is concave. The seventh lens includes a seventh object-side surface near the object plane and a seventh image-side surface near the image plane. The seventh object-side surface is convex, and the seventh image-side surface is convex. The eighth lens includes an eighth object-side surface near the object plane and an eighth image-side surface near the image plane. The eighth object-side surface is convex, and the eighth image-side surface is concave.

10. The optical lens according to claim 1, characterized in that, The optical lens has an aperture of F and a total optical length of TTL. Where F≥1.1, TTL<50mm.

Images