Optical lens and imaging device

Abstract

The utility model provides an optical lens and an imaging device, and belongs to the technical field of optical imaging. The optical lens comprises a first lens with negative focal power, a second lens with negative focal power, a third lens with negative focal power, a fourth lens with positive focal power, a fifth lens with positive focal power, a sixth lens with negative focal power and a seventh lens with positive focal power which are sequentially arranged from the object side to the image side. The optical lens comprises an eighth lens with positive focal power and an image plane, so that the horizontal field angle of the optical lens reaches over 126 degrees, the aperture value is less than or equal to 2.0, and the height of the image plane reaches 6.6 mm. Wherein the second lens, the third lens, the seventh lens and the eighth lens are plastic aspheric lenses, and the other lenses are spherical lenses. According to the scheme, the eight lenses are adopted, and the focal power and the shape matching relation of each lens are reasonably set, so that the optical lens which is small in size, high in resolution, low in cost and free of virtual focus at high temperature is realized.

Description

Technical Field

[0001] The utility model relates to the technical field of optical imaging, in particular to an optical lens and an imaging device. Background Art

[0002] With the advancement of technology, the structures of various components are becoming increasingly complex, and consumer demands are also becoming increasingly demanding. Lenses need to offer the advantages of capturing a wide range of images while also meeting high and low temperature requirements. Currently, there is a widespread problem of being unable to achieve a wide viewing angle, low cost, high pixel count, no blurring at high and low temperatures, and good night vision. For example, some lenses sacrifice resolution or use plastic aspherical surfaces to reduce costs. However, due to the large temperature fluctuations in the actual environment, these lenses are often prone to blurring at high and low temperatures, affecting their performance. Meanwhile, some lenses offer excellent night vision and high image quality, but are expensive and lack market acceptance. Utility Model Content

[0003] The main purpose of the utility model is to provide an optical lens and an imaging device, aiming to provide an optical lens with a large viewing angle, low cost, no defocusing at high and low temperatures, and good infrared confocal effect.

[0004] To achieve the above objectives, the present invention provides an optical lens, the optical lens having an object side and an image side arranged opposite to each other along an optical axis, the optical lens including, arranged in order from the object side to the image side, a first lens with negative optical power, a second lens with negative optical power, a third lens with negative optical power, a fourth lens with positive optical power, a fifth lens with positive optical power, a sixth lens with negative optical power, a seventh lens with positive optical power, an eighth lens with positive optical power, and an image plane, so that the horizontal field angle of the optical lens reaches 126°, the aperture value is less than or equal to 2.0, and the image plane height reaches 6.6 mm;

[0005] The second lens, the third lens, the seventh lens and the eighth lens are plastic aspherical lenses, and the first lens, the fourth lens, the fifth lens and the sixth lens are spherical lenses.

[0006] In one embodiment, the optical lens further includes a stop, and the stop is disposed between the fourth lens and the fifth lens.

[0007] In one embodiment, the optical lens further includes a filter and a protective glass sequentially arranged between the eighth lens and the image plane from the object side to the image side.

[0008] In one embodiment, the fifth lens and the sixth lens are cemented together.

[0009] In one embodiment, the first lens is a meniscus lens, and its object-side surface is convex;

[0010] The second lens is a meniscus lens, and its object side surface is convex;

[0011] The third lens is a biconcave lens;

[0012] The fourth lens is a biconvex lens;

[0013] The fifth lens is a biconvex lens;

[0014] The sixth lens is a biconcave lens;

[0015] The seventh lens is a biconvex lens;

[0016] The eighth lens is a biconvex lens.

[0017] In one embodiment, the focal length of the first lens is f1, the focal length of the second lens is f2, the focal length of the third lens is f3, the focal length of the fourth lens is f4, the focal length of the fifth lens is f5, the focal length of the sixth lens is f6, the focal length of the seventh lens is f7, and the focal length of the eighth lens is f8, wherein:

[0018] -15<f1<-8, -15<f2<-8, -8<f3<-4, 4<f4<9, 3<f5<8, -6<f6<-2, 4<f7<10, 10<f8<25.

[0019] In one embodiment, the refractive index of the first lens is n1 and the Abbe coefficient is v1, the refractive index of the second lens is n2 and the Abbe coefficient is v2, the refractive index of the third lens is n3 and the Abbe coefficient is v3, the focal refractive index of the fourth lens is n4 and the Abbe coefficient is v4, the refractive index of the fifth lens is n5 and the Abbe coefficient is v5, the refractive index of the sixth lens is n6 and the Abbe coefficient is v6, the refractive index of the seventh lens is n7 and the Abbe coefficient is v7, and the refractive index of the eighth lens is n8 and the Abbe coefficient is v8, wherein:

[0020] 1.55≤n1≤1.75,1.50≤n2≤1.60,1.50≤n3≤1.60,1.75≤n4≤1.95,1.50≤n5≤1.70,1.70≤n6≤1.95,1.50≤n7≤1.60,1.50≤n8≤1.70,45.0≤v1≤75.0,50.0≤v2≤65.0,50.0≤v3≤65.0,25.0≤v4≤45.0,50.0≤v5≤75.0,25.0≤v6≤35.0,50.0≤v7≤65.0,50.0≤v8≤65.0。

[0021] In one embodiment, the effective focal length of the optical lens is EFL, and the total optical length of the optical lens is TTL, wherein:

[0022] TTL / EFL≤10.5.

[0023] In one embodiment, the diameter of the first lens is D1, and the image plane diameter of the optical lens is IC, wherein:

[0024] D1<15mm, IC≤6.6mm.

[0025] The utility model further provides an imaging device, comprising the above-mentioned optical lens, wherein the optical lens has an object side and an image side arranged opposite to each other along an optical axis direction, and the optical lens comprises a first lens with negative optical power, a second lens with negative optical power, a third lens with negative optical power, a fourth lens with positive optical power, a fifth lens with positive optical power, a sixth lens with negative optical power, a seventh lens with positive optical power, an eighth lens with positive optical power, and an image plane, arranged in sequence from the object side to the image side, so that the horizontal field angle of the optical lens reaches 126°, the aperture value is less than or equal to 2.0, and the image plane height reaches 6.6 mm;

[0026] The second lens, the third lens, the seventh lens and the eighth lens are plastic aspherical lenses, and the first lens, the fourth lens, the fifth lens and the sixth lens are spherical lenses.

[0027] The technical solution provided by this utility model facilitates light collection in the optical system by providing a negative first lens, effectively increasing the field of view. The fourth lens, with a positive fourth lens, assumes a larger portion of the system's optical power, altering the propagation direction of the light beam and correcting aberrations in the off-axis field of view, further facilitating the formation of the light beam on the image plane. By configuring the second, third, seventh, and eighth lenses as plastic aspheric lenses, the proportion of glass lenses used is reduced, lowering costs while correcting various aberrations, improving edge quality, and achieving high-quality imaging. The plastic lenses are all made of low-refractive-index materials, offering excellent processability, stable molding, low sensitivity, and a high yield rate. By configuring the other lenses as spherical lenses, aberrations are effectively reduced, ensuring that the lens retains focus in both high and low temperature conditions. The lens's light path is smooth, allowing for more light to be introduced while maintaining a more compact structure, keeping the total optical length within 25 mm. In terms of aperture, the aperture value F satisfies F≤2.0, and the image plane height can reach φ6.6 mm, enabling clear imaging even in low light conditions. By properly setting the focal length ratio, the optical system achieves excellent athermalization, more stable operating performance, and a horizontal field of view exceeding 126°, with a CRA ≤ 12°. It is compatible with a variety of sensors and has broad application prospects. By utilizing eight lenses and properly setting the optical power and shape of each lens, an optical lens with excellent performance such as a wide viewing angle, high pixel count, good infrared confocal effect, high yield, excellent manufacturability, and excellent athermalization is achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0029] Figure 1 A schematic structural diagram of an embodiment of an optical lens provided by the present utility model;

[0030] Figure 2 for Figure 1 Schematic diagram of vertical axis chromatic aberration curve of medium optical lens;

[0031] Figure 3 for Figure 1 Light fan diagram of the medium optical lens;

[0032] Figure 4 for Figure 1 Schematic diagram of field curvature distortion of optical lens;

[0033] Figure 5 for Figure 1MTF curve of medium optical lens at 20℃;

[0034] Figure 6 for Figure 1 Through-focus MTF curve of a medium optical lens in the visible light band at 20°C;

[0035] Figure 7 for Figure 1 Through-focus MTF curve of a medium optical lens in the infrared band at 20°C;

[0036] Figure 8 for Figure 1 Through-focus MTF curve of the medium optical lens in the visible light band at -30°C;

[0037] Figure 9 for Figure 1 Through-focus MTF curve of a medium optical lens in the visible light band at 85°C.

[0038] Description of Figure Numbers:

[0039] 1000. Optical lens; 1. First lens; 2. Second lens; 3. Third lens; 4. Fourth lens; 5. Fifth lens; 6. Sixth lens; 7. Seventh lens; 8. Eighth lens; a. Aperture; b. Filter; c. Protective glass; d. Image plane.

[0040] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0042] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0043] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of such features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or a scheme in which A and B are satisfied at the same time. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0044] With the advancement of technology, the structures of various components are becoming increasingly complex, and consumer demands are also becoming increasingly demanding. Lenses must offer the advantages of capturing a wide image format while also meeting high and low temperature requirements. Currently, these products generally struggle to balance wide viewing angles, low cost, high pixel count, stable focus at high and low temperatures, and good night vision. For example, some lenses sacrifice resolution or use plastic aspherical surfaces to reduce costs. However, due to the high heat generated by projectors, these lenses are often prone to defocusing at high and low temperatures, affecting their performance. Meanwhile, some lenses offer excellent night vision and high-quality images, but are expensive and lack market acceptance.

[0045] The main purpose of the utility model is to provide an optical lens and an imaging device, aiming to provide an optical lens with a large viewing angle, low cost, no defocusing at high and low temperatures, and good infrared confocal effect.

[0046] See also Figure 1 The present invention proposes an optical lens 1000, wherein the optical lens 1000 has an object side and an image side arranged opposite to each other along the optical axis direction, and the optical lens 1000 includes a first lens 1 with negative optical focal length, a second lens 2 with negative optical focal length, a third lens 3 with negative optical focal length, a fourth lens 4 with positive optical focal length, a fifth lens 5 with positive optical focal length, a sixth lens 6 with negative optical focal length, a seventh lens 7 with positive optical focal length, an eighth lens 8 with positive optical focal length, and an image plane d, which are arranged in sequence from the object side to the image side, so that the horizontal field angle of the optical lens 1000 reaches 126° or more, the aperture value is less than or equal to 2.0, and the image plane d height reaches 6.6 mm; wherein the second lens 2, the third lens 3, the seventh lens 7, and the eighth lens 8 are plastic aspherical lenses, and the first lens 1, the fourth lens 4, the fifth lens 5, and the sixth lens 6 are spherical lenses.

[0047] The technical solution provided by this utility model utilizes a negative-power first lens 1 to facilitate light collection in the optical system, effectively increasing the field of view. The positive-power fourth lens 4 contributes to the system's greater optical power, altering the beam's propagation direction and correcting aberrations in the off-axis field of view, further facilitating the beam's formation on the image plane. By utilizing plastic aspherical lenses for the second, third, seventh, and eighth lenses, the use of glass lenses is reduced, lowering costs while also correcting various aberrations and improving edge quality, resulting in high-quality imaging. The plastic lenses are all constructed from low-refractive-index materials, offering excellent processability, stable molding, low sensitivity, and a high yield rate. By utilizing spherical lenses for the other lenses, aberrations are effectively reduced, ensuring no defocusing in high or low temperature conditions. The lens's smooth light path allows for more light while maintaining a more compact structure, keeping the total optical length within 25 mm. The aperture value (F) satisfies F≤2.0, and the image plane height can reach φ6.6 mm, enabling clear imaging even in low light conditions. By properly setting the focal length ratio, the optical system achieves excellent athermalization, resulting in more stable performance. The horizontal field of view reaches over 126°, with a CRA ≤ 12°, making it compatible with a wide range of sensors and promising applications. By utilizing eight lenses and rationally configuring the focal length and shape of each lens, the Optical Lens 1000 achieves excellent performance, including a wide viewing angle, high pixel count, excellent infrared confocal effect, high yield, superior manufacturability, and excellent athermalization.

[0048] It should be noted that the characteristic of an aspheric lens is that the curvature changes continuously from the center of the lens to the periphery of the lens, which is different from a spherical lens that has a constant curvature from the center of the lens to the periphery of the lens.

[0049] Furthermore, the optical lens 1000 includes an aperture a, which is disposed between the fourth lens element 4 and the fifth lens element 5. The aperture a limits the aperture of the light beam on the optical axis, intercepting some light, thereby reducing light spots, improving image contrast, and also expanding the target surface and enhancing image quality. Adjusting the light flux of the aperture a according to actual conditions can help further improve imaging quality.

[0050] Furthermore, the optical lens 1000 also includes a filter b and a protective glass c, positioned sequentially between the eighth lens element 8 and the image plane d, from the object side to the image side. The filter b is used to filter out stray light outside the operating band, thereby reducing optical noise and simplifying subsequent photoelectric module processing. The filter b can also be used to adjust the color of the final image. The protective glass c provides waterproof and dustproof protection for the lens, enhancing the lens's anti-interference capabilities and improving image quality.

[0051] Furthermore, to improve the optical system's image quality, reduce light energy loss, increase image clarity, protect the scaled surface, and further optimize the manufacturing process to meet design requirements, the fifth lens 5 and the sixth lens 6 are cemented together. This rational use of the cemented components and the appropriate distribution of optical power effectively correct aberrations and achieve high-temperature athermalization. It also effectively reduces chromatic aberration and enhances image clarity.

[0052] Specifically, in a preferred embodiment, please refer to Figure 1 The first lens 1 is a concave-convex lens, and its object-side surface is convex; the second lens 2 is a concave-convex lens, and its object-side surface is convex; the third lens 3 is a biconcave lens; the fourth lens 4 is a biconvex lens; the fifth lens 5 is a biconvex lens; the sixth lens 6 is a biconcave lens; the seventh lens 7 is a biconvex lens; and the eighth lens 8 is a biconvex lens.

[0053] Furthermore, the focal length of the first lens 1 is f1, the focal length of the second lens 2 is f2, the focal length of the third lens 3 is f3, the focal length of the fourth lens 4 is f4, the focal length of the fifth lens 5 is f5, the focal length of the sixth lens 6 is f6, the focal length of the seventh lens 7 is 7, and the focal length of the eighth lens 8 is f8, wherein: -15<f1<-8, -15<f2<-8, -8<f3<-4, 4<f4<9, 3<f5<8, -6<f6<-2, 4<f7<10, 10<f8<25. This embodiment is a preferred embodiment. By combining different lenses and reasonably allocating their optical powers, the entire lens has good performance such as low cost and high pixel count.

[0054] Furthermore, the refractive index of the first lens 1 is n1 and the dispersion coefficient is v1, the refractive index of the second lens 2 is n2 and the dispersion coefficient is v2, the refractive index of the third lens 3 is n3 and the dispersion coefficient is v3, the focal refractive index of the fourth lens 4 is n4 and the dispersion coefficient is v4, the refractive index of the fifth lens 5 is n5 and the dispersion coefficient is v5, the refractive index of the sixth lens 6 is n6 and the dispersion coefficient is v6, the refractive index of the seventh lens 7 is n7 and the dispersion coefficient is v7, and the refractive index of the eighth lens 8 is n8 and the dispersion coefficient is v8, wherein: 1.55≤n1 ≤1.75, 1.50≤n2≤1.60, 1.50≤n3≤1.60, 1.75≤n4≤1.95, 1.50≤n5≤1.70, 1.70≤n6≤1.95, 1.50≤n7≤1.60, 1.50≤n8≤1.70, 45.0≤v1≤75.0, 50.0≤v2≤65.0, 50.0≤v3≤65.0, 25.0≤v4≤45.0, 50.0≤v5≤75.0, 25.0≤v6≤35.0, 50.0≤v7≤65.0, 50.0≤v8≤65.0. This embodiment is a preferred embodiment. By combining different lenses and reasonably allocating their refractive indices and dispersion coefficients, the optical lens 1000 has low cost, high pixel count, and good athermal performance.

[0055] In one embodiment of the present invention, the effective focal length of the optical lens 1000 is EFL, and the total optical length of the optical lens 1000 is TTL, where: TTL / EFL ≤ 10.5. By properly limiting the size of the EFL, the total optical length can be further limited, making the entire optical system more compact and helping to control the focal length of the optical lens 1000.

[0056] In one embodiment of the present invention, the total optical length of the optical lens 1000 is TTL, the diameter of the first lens 1 is D1, and the image plane diameter of the optical lens 1000 is IC, where: D1 < 15 mm, IC ≤ 6.6 mm. This design, by limiting the numerical relationship of the aforementioned optical system characteristics, can prevent the aperture of the optical lens 1000 from being excessively large, thereby meeting the installation space requirements of the final product. By limiting the specific values ​​of the total optical length and the diameter of the first lens 1, the lens size can be appropriately limited, thereby facilitating lens miniaturization.

[0057] It is worth mentioning that the surface shape of the aspheric lens in the optical lens 1000 in this embodiment should satisfy the following equation:

[0058]

[0059] Where c is the curvature corresponding to the radius; y is the radial coordinate (its units are the same as the lens length); k is the conic coefficient, and A, B, C, D, E, F... represent the fourth-order, sixth-order, eighth-order, tenth-order, twelfth-order, fourteenth-order... aspheric coefficients, respectively. These parameters can be used to set the shape and dimensions of the lens's aspheric surfaces facing the object and image sides.

[0060] Among them, when k is less than -1, the corresponding surface curve of the lens is a hyperbola; when k is equal to -1, the corresponding surface curve of the lens is a parabola; when -1 is less than k and less than 0, the corresponding surface curve of the lens is an ellipse; when k is equal to 0, the corresponding surface curve of the lens is a circle; when k is greater than 0, the corresponding surface curve of the lens is an oblate circle.

[0061] It should be noted that the basic parameter table of the optical lens 1000 in an embodiment provided by the present invention is shown in Table 1, wherein the units of the curvature radius and thickness are both millimeters (mm).

[0062] Table 1

[0063]

[0064]

[0065] In this embodiment, the aspheric coefficients of the aspheric lens in the optical lens 1000 include: the quadratic surface coefficient k, the fourth-order aspheric coefficient A, the sixth-order aspheric coefficient B, the eighth-order aspheric coefficient C, the tenth-order aspheric coefficient D, the twelfth-order aspheric coefficient E, and the fourteenth-order aspheric coefficient F of the surface, as shown in Table 2 below.

[0066] Table 2

[0067] Face number k A B C D E F 3 -85.091 1.50E-03 6.30E-05 -3.11E-06 8.88E-08 -1.45E-09 2.47E-11 4 -1.490 9.24E-04 4.54E-04 1.63E-06 -5.26E-07 9.12E-08 1.82E-09 5 -1.242 6.35E-03 -7.41E-04 5.49E-05 -2.01E-06 0.00E+00 0.00E+00 6 0.000 1.01E-02 -7.79E-04 6.22E-05 -2.28E-06 0.00E+00 0.00E+00 13 0.028 5.28E-04 -2.13E-04 2.21E-05 -9.68E-07 -1.05E-07 1.47E-08 14 -2.061 -1.88E-03 2.15E-04 -6.18E-06 -3.09E-07 0.00E+00 0.00E+00 15 -98.210 -3.39E-03 -2.11E-04 1.87E-05 -2.56E-08 0.00E+00 0.00E+00 16 35.941 -4.52E-03 9.56E-05 -2.73E-06 5.77E-07 0.00E+00 0.00E+00

[0068] Please refer to Figure 2 , is a schematic diagram of the vertical axis chromatic aberration curve of the optical lens 1000 in this embodiment. It can be seen from the figure that the vertical axis chromatic aberration of the optical lens 1000 at different wavelengths is controlled within the range of (-1μm, +5μm), indicating that the vertical axis chromatic aberration of the optical lens 1000 is well controlled and can meet the requirements of wide spectrum applications in the full band.

[0069] Please refer to Figure 3, is the light fan diagram of the optical lens 1000 in this embodiment, where the abscissa is the normalized beam aperture and the ordinate is the vertical axis aberration. Ideally, each curve should completely coincide with the abscissa axis, so that all light rays in this field of view focus on the same point on the image plane d; the ordinate in the image can also be expressed as the maximum dispersion range of the light beam on the ideal image plane d. The light fan diagram can not only reflect the monochromatic aberration of different wavelengths, but also indicate the magnitude of the vertical axis chromatic aberration. As can be seen from the figure, the optical lens 1000 is relatively close to the abscissa at each wavelength in each field of view, indicating that the vertical axis aberration of each wavelength is well corrected. In addition, the curves of each color do not have obvious dispersion, indicating that the optical lens 1000 also has a good correction for chromatic aberration, ensuring that the optical lens 1000 meets the imaging requirement of forming clear images across the entire wavelength range.

[0070] Please refer to Figure 4 , is a schematic diagram of the field curvature distortion of the optical lens 1000 in this embodiment. Different colors represent different wavelengths. For the same color, the right curve represents the meridional field curvature, and the left curve represents the sagittal field curvature. The figure shows that the sagittal field curvature of this lens is no greater than 0.1mm, indicating that this lens can effectively correct chromatic aberration. The other curve in the figure is the system distortion curve. Distortion does not affect the system's clarity, but it will cause image distortion. The optical distortion of this lens is less than 4%.

[0071] Please refer to Figure 5 , is a schematic diagram of the MTF of the optical lens 1000 at 20°C in this embodiment, which shows the imaging quality of three wavelengths of light. The horizontal axis represents the number of line pairs, and the vertical axis represents the resolution. The higher the value of the vertical axis, the stronger the resolution and the higher the image quality restoration. The MTF values ​​are all greater than 0.2, which basically meets the imaging quality requirements.

[0072] Please refer to Figure 6 、 Figure 8 and Figure 9 , is a defocus MTF curve diagram of the optical lens 1000 in this embodiment under the visible light band at 20℃, -30℃ and 85℃ respectively. It can be seen from the figure that the defocus of the lens does not exceed 0.006mm in the three states, basically achieving a state of no defocus at high and low temperatures.

[0073] Please refer to Figure 7 , is a defocus MTF curve of the optical lens 1000 in this embodiment at 20°C in the infrared band. From the figure, it can be seen that the lens defocus does not exceed 0.018mm, basically achieving a state of no defocus in the infrared band.

[0074] In this embodiment, the focal length of the optical lens 1000 is 2.41 mm, the aperture value is 2.0, the image plane diameter is 6.5 mm, and the diagonal field of view is 160°. While having a large field of view, various aberrations of the lens are corrected, the imaging quality is high, and clear imaging can be achieved even in low light. The lens size is small, and the night vision imaging effect is good. It does not defocus under high and low temperature conditions, especially in the temperature range of -30°C to 85°C, and the working performance is more stable.

[0075] The present invention also provides an imaging device, which includes the above-mentioned optical lens 1000. Since the imaging device includes the optical lens 1000, the specific structure of the optical lens 1000 refers to the above-mentioned embodiments. Since the optical lens 1000 of this imaging device adopts all the technical solutions of all the above-mentioned embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above-mentioned embodiments, which will not be described one by one here.

[0076] The above description is merely an exemplary embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made using the contents of the present invention specification and drawings under the technical concept of the present invention, or direct / indirect application in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. An optical lens, characterized in that: The optical lens has an object side and an image side that are oppositely arranged along the optical axis, and the optical lens includes a first lens with negative optical power, a second lens with negative optical power, a third lens with negative optical power, a fourth lens with positive optical power, a fifth lens with positive optical power, a sixth lens with negative optical power, a seventh lens with positive optical power, an eighth lens with positive optical power, and an image plane, which are arranged in sequence from the object side to the image side, so that the horizontal field angle of the optical lens reaches 126 degrees or more, the aperture value is less than or equal to 2.0, and the image plane height reaches 6.6 mm; The second lens, the third lens, the seventh lens and the eighth lens are plastic aspherical lenses, and the first lens, the fourth lens, the fifth lens and the sixth lens are spherical lenses.

2. The optical lens according to claim 1, wherein: The optical lens further includes a stop, which is disposed between the fourth lens and the fifth lens.

3. The optical lens according to claim 1, wherein: The optical lens further includes a filter and a protective glass sequentially arranged between the eighth lens and the image plane from the object side to the image side.

4. The optical lens according to claim 1, wherein: The fifth lens and the sixth lens are cemented together.

5. The optical lens according to claim 1, wherein: The first lens is a concave-convex lens, and its object-side surface is convex; The second lens is a meniscus lens, and its object side surface is convex; The third lens is a biconcave lens; The fourth lens is a biconvex lens; The fifth lens is a biconvex lens; The sixth lens is a biconcave lens; The seventh lens is a biconvex lens; The eighth lens is a biconvex lens.

6. The optical lens according to claim 5, wherein: The focal length of the first lens is f1, the focal length of the second lens is f2, the focal length of the third lens is f3, the focal length of the fourth lens is f4, the focal length of the fifth lens is f5, the focal length of the sixth lens is f6, the focal length of the seventh lens is 7, and the focal length of the eighth lens is f8, wherein: -15<f1<-8, -15<f2<-8, -8<f3<-4, 4<f4<9, 3<f5<8, -6<f6<-2, 4<f7<10, 10<f8<25.

7. The optical lens according to claim 5, wherein: The refractive index of the first lens is n1 and the dispersion coefficient is v1, the refractive index of the second lens is n2 and the dispersion coefficient is v2, the refractive index of the third lens is n3 and the dispersion coefficient is v3, the focal refractive index of the fourth lens is n4 and the dispersion coefficient is v4, the refractive index of the fifth lens is n5 and the dispersion coefficient is v5, the refractive index of the sixth lens is n6 and the dispersion coefficient is v6, the refractive index of the seventh lens is n7 and the dispersion coefficient is v7, and the refractive index of the eighth lens is n8 and the dispersion coefficient is v8, wherein: 1.55≤n1≤1.75, 1 .50≤n2≤1.60,1.50≤n3≤1.60,1.75≤n4≤1.95,1.50≤n5≤1.70,1.70≤n6≤1.95,1.50≤n7≤1.60,1.50≤n8≤1.70,45.0≤v1≤75.0,50.0≤v2≤65.0,50.0≤v3≤65.0,25.0≤v4≤45.0,50.0≤v5≤75.0,25.0≤v6≤35.0,50.0≤v7≤65.0,50.0≤v8≤65.0。 8. The optical lens according to claim 1, wherein: The effective focal length of the optical lens is EFL, and the total optical length of the optical lens is TTL, wherein: TTL / EFL≤10.

5.

9. The optical lens according to claim 1, wherein: The diameter of the first lens is D1, and the image diameter of the optical lens is IC, wherein: D1<15mm, IC≤6.6mm.

10. An imaging device, characterized in that: Comprising the optical lens according to any one of claims 1 to 9.

Images