A vehicle-mounted camera and an optical lens thereof

Abstract

The application discloses a vehicle-mounted camera and an optical lens thereof. The optical 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 arranged in sequence along an optical axis from an object side to an image side. The first lens has a negative focal power, the second lens has a negative focal power, the third lens has a positive focal power, the fourth lens has a positive focal power, the fifth lens has a positive focal power, the sixth lens has a positive focal power, the seventh lens has a negative focal power, and the eighth lens has a negative focal power. The first lens, the second lens, the third lens, the fourth lens, the sixth lens and the seventh lens are glass spherical lenses. The fifth lens and the eighth lens are glass aspherical lenses. The focal length F of the optical lens and the total optical length TTL of the optical lens satisfy TTL / F<5.5. The optical lens can meet the requirements of high pixels, miniaturization, large aperture and weak ghost image.

Description

Technical Field

[0001] The present invention relates to the field of optical device technology, and in particular to a vehicle-mounted camera and its optical lens. Background Technology

[0002] With the development of technology, driver assistance systems applied to vehicles are gradually evolving from assisted driving to true autonomous driving. In driver assistance systems, the onboard camera is the core sensor for environmental perception, and its detection range, recognition accuracy, and nighttime imaging quality are key factors in the safety of using the system.

[0003] Currently, the optical lenses used in automotive cameras need to meet the requirements of simple structure, small size, and low cost while having high pixel resolution, large aperture, and stable imaging over a wide range of temperatures. This has become an urgent technical problem to be solved. Summary of the Invention

[0004] This invention provides a vehicle-mounted camera and its optical lens, which ensures that the optical lens has high pixel resolution, a large aperture, and stable imaging over a wide temperature range, while also meeting the requirements of simple structure, small size, and low cost.

[0005] In a first aspect, the present invention provides 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 arranged sequentially along the optical axis from the object side to the image side; The first lens has negative optical power, the second lens has negative optical power, the third lens has positive optical power, the fourth lens has positive optical power, the fifth lens has positive optical power, the sixth lens has positive optical power, the seventh lens has negative optical power, and the eighth lens has negative optical power. The focal length F of the optical lens and the total optical length TTL of the optical lens satisfy the following condition: TTL / F < 5.5.

[0006] Optionally, the object-side surface of the first lens is convex, and the image-side surface of the first lens is concave. The object-side surface of the second lens is concave, and the image-side surface of the second lens is also concave. The object-side surface of the third lens is convex, and the image-side surface of the third lens is convex. The object-side surface of the fourth lens is convex, and the image-side surface of the fourth lens is either flat or concave. The object-side surface of the fifth lens is convex, and the image-side surface of the fifth lens is concave. The object-side surface of the sixth lens is convex, and the image-side surface of the sixth lens is convex. The object-side surface of the seventh lens is concave, and the image-side surface of the seventh lens is convex. The object-side surface of the eighth lens is concave, and the image-side surface of the eighth lens is convex.

[0007] Optionally, the optical power of the first lens to the eighth lens satisfies the following condition: -0.15≤Φ1 / Φ≤-0.05; -0.27≤Φ2 / Φ≤-0.17; 0.10≤Φ3 / Φ≤0.20; 0.02≤Φ4 / Φ≤0.12; 0.02≤Φ5 / Φ≤0.088; 0.10≤Φ6 / Φ≤0.20; -0.16≤Φ7 / Φ≤-0.05; -0.05≤Φ8 / Φ≤0.05; Wherein, Φ is the optical power of the optical lens, Φ1 is the optical power of the first lens, Φ2 is the optical power of the second lens, Φ3 is the optical power of the third lens, Φ4 is the optical power of the fourth lens, Φ5 is the optical power of the fifth lens, Φ6 is the optical power of the sixth lens, Φ7 is the optical power of the seventh lens, and Φ8 is the optical power of the eighth lens.

[0008] Optionally, the refractive index and dispersion coefficient of the first lens to the eighth lens satisfy the following conditions: 1.45≤n1≤1.65; 55.8≤v1≤80.2; 1.80≤n²≤1.90; 20.90≤v²≤29.90; 1.78≤n3≤1.89; 45.20≤v3≤55.60; 1.90≤n4≤2.00;12.00≤v4≤21.60; 1.45≤n5≤1.55; 31.00≤v5≤60.40; 1.52≤n6≤1.66; 60.90≤v6≤71.30; 1.90≤n7≤2.00; 12.00≤v7≤21.00; 1.69≤n8≤1.92; 21.80≤v8≤42.10; Wherein, n1 is the refractive index of the first lens, n2 is the refractive index of the second lens, n3 is the refractive index of the third lens, n4 is the refractive index of the fourth lens, n5 is the refractive index of the fifth lens, n6 is the refractive index of the sixth lens, n7 is the refractive index of the seventh lens, n8 is the refractive index of the eighth lens, v1 is the dispersion coefficient of the first lens, v2 is the dispersion coefficient of the second lens, v3 is the dispersion coefficient of the third lens, v4 is the dispersion coefficient of the fourth lens, v5 is the dispersion coefficient of the fifth lens, v6 is the dispersion coefficient of the sixth lens, v7 is the dispersion coefficient of the seventh lens, and v8 is the dispersion coefficient of the eighth lens.

[0009] Optionally, the first lens, the second lens, the third lens, the fourth lens, the sixth lens, and the seventh lens are all spherical lenses; the fifth lens and the eighth lens are aspherical lenses.

[0010] Optionally, the second lens and the third lens form a cemented lens.

[0011] Optionally, the sixth and seventh lenses form a cemented lens.

[0012] Optionally, the optical lens further includes an aperture stop; the aperture stop is located in the optical path between the fourth lens and the fifth lens.

[0013] Optionally, the entrance pupil diameter ENPD of the optical lens and the total optical length TTL of the optical lens satisfy the following condition: ENPD / TTL > 0.1.

[0014] Optionally, the entrance pupil diameter ENPD of the optical lens and the image height H of the optical lens at the maximum field of view satisfy the following condition: H / ENPD < 1.3.

[0015] In a second aspect, the present invention provides a vehicle-mounted camera, comprising: an optical lens as described in the first aspect.

[0016] The technical solution of this invention, by constructing an optical lens composed of eight lenses with varying optical power, and by rationally allocating the optical power, surface shape, and materials of each lens, results in an optical lens with a simple structure, high pixel resolution, a large aperture, weak ghosting, and low cost, as well as stable imaging over a wide temperature range. Simultaneously, by setting the focal length F and the total optical length TTL of the optical lens to satisfy TTL / F < 5.5, the optical lens can be made relatively small, meeting the requirement for a compact size. Therefore, when applied to an automotive camera, this ensures high image clarity, which improves the accuracy of parameter recognition in assisted driving when images captured by the automotive camera lens are used as parameters, thereby enhancing the safety and reliability of assisted driving. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of an optical lens provided in an embodiment of the present invention; Figures 2 to 12 yes Figure 1 A schematic diagram of the light beam fan of the optical lens shown; Figure 13 yes Figure 1 A schematic diagram of the axial aberration curve of the optical lens shown. Figure 14 yes Figure 1 A schematic diagram of the field curvature distortion curve of the optical lens shown; Figure 15 This is a schematic diagram of another optical lens structure provided in an embodiment of the present invention; Figures 16 to 26 yes Figure 15 A schematic diagram of the light beam fan of the optical lens shown; Figure 27 yes Figure 15 A schematic diagram of the axial aberration curve of the optical lens shown. Figure 28 yes Figure 15 A schematic diagram of the field curvature distortion curve of the optical lens shown; Figure 29 This is a schematic diagram of the structure of another optical lens provided in an embodiment of the present invention; Figures 30 to 40 yes Figure 29 A schematic diagram of the axial aberration curve of the optical lens shown. Figure 41 yes Figure 29 A schematic diagram of the axial aberration curve of the optical lens shown. Figure 42 yes Figure 29 The diagram shows the field curvature distortion curve of the optical lens. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be fully described below with reference to the accompanying drawings of the embodiments of this invention through specific implementation methods. Obviously, the described embodiments are only some, not all, embodiments of this invention. Various modifications and variations can be made to this invention without departing from the spirit or scope of this invention, which will be obvious to those skilled in the art. Therefore, this invention is intended to cover modifications and variations of this invention that fall within the scope of the corresponding claims (the claimed technical solutions) and their equivalents.

[0019] Furthermore, the terms "first," "second," and similar terms used in the embodiments of this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, terms such as "an," "one," or "the" do not indicate a quantity limitation, but rather indicate the presence of at least one. Terms such as "including" or "comprising" mean that the element or object preceding the word encompasses the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are only used to indicate relative positional relationships, and these relative positional relationships may change accordingly when the absolute position of the described object changes. In addition, descriptions of "same" or "equal" in the embodiments of this disclosure do not mean that two objects are completely equal in size or shape; they are allowed to be approximately the same or approximately equal within a certain error range.

[0020] It should be noted that the implementation methods provided in the embodiments of the present invention can be combined with each other without contradiction.

[0021] This invention provides an optical lens. Figure 1 This is a schematic diagram of the structure of an optical lens provided in an embodiment of the present invention, such as... Figure 1 As shown, the optical lens includes: a first lens 10, a second lens 20, a third lens 30, a fourth lens 40, a fifth lens 50, a sixth lens 60, a seventh lens 70, and an eighth lens 80 arranged sequentially along the optical axis from the object side to the image side; the first lens 10 has negative optical power, the second lens 20 has negative optical power, the third lens 30 has positive optical power, the fourth lens 40 has positive optical power, the fifth lens 50 has positive optical power, the sixth lens 60 has positive optical power, the seventh lens 70 has negative optical power, and the eighth lens 80 has negative optical power.

[0022] As can be understood, optical power equals 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 optical power, the stronger the bending ability of light; the smaller the absolute value, the weaker the bending ability. When optical power is positive, the refraction of light is converging; when 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).

[0023] In this embodiment, the optical lens consists of eight lenses, from the first lens 10 to the eighth lens 80, each with a specific optical power. By setting the first lens 10 and the second lens 20 to have negative optical power, light rays with a large angle of incidence can enter the optical lens and propagate smoothly to the third lens 30, thereby giving the optical lens a large field of view. Simultaneously, the third lens 30, fourth lens 40, fifth lens 50, sixth lens 60, seventh lens 70, and eighth lens 80 are all set to positive optical power, ensuring that the optical lens meets the requirements of small size, low cost, large aperture, and high pixel resolution.

[0024] In an optional embodiment, the optical power of the first lens 10 to the eighth lens 80 satisfies the following condition: -0.15≤Φ1 / Φ≤-0.05; -0.27≤Φ2 / Φ≤-0.17; 0.10≤Φ3 / Φ≤0.20; 0.02≤Φ4 / Φ≤0.12; 0.02≤Φ5 / Φ≤0.088; 0.10≤Φ6 / Φ≤0.20; -0.16≤Φ7 / Φ≤-0.05; -0.05≤Φ8 / Φ≤0.05; Wherein, Φ is the optical power of the lens, Φ1 is the optical power of the first lens 10, Φ2 is the optical power of the second lens 20, Φ3 is the optical power of the third lens 30, Φ4 is the optical power of the fourth lens 40, Φ5 is the optical power of the fifth lens 50, Φ6 is the optical power of the sixth lens 60, Φ7 is the optical power of the seventh lens 70, and Φ8 is the optical power of the eighth lens 80.

[0025] This configuration, by rationally allocating the optical power of each lens, ensures that the optical lens can meet the requirements of small size, low cost, large aperture, and high pixel resolution.

[0026] Optionally, the first lens 10, the second lens 20, the third lens 30, the fourth lens 40, the sixth lens 60 and the seventh lens 70 are all glass spherical lenses, and the fifth lens 50 and the eighth lens 80 are glass aspherical lenses.

[0027] Spherical lenses are characterized by a constant curvature from the center to the periphery, ensuring simple lens setup. Aspherical lenses, on the other hand, exhibit a continuous change in curvature from the center to the periphery, allowing them to correct edge focusing deviations caused by fixed curvature and ensuring image sharpness. Furthermore, optimized surface design helps reduce aberrations (such as distortion and chromatic aberration), allowing for a larger aperture while maintaining high resolution. In addition, a single aspherical lens can replace multiple spherical lenses, reducing system complexity. Glass lenses have a low coefficient of thermal expansion and good stability, balancing high and low temperatures. Glass aspherical lenses can efficiently correct various optical aberrations, ensuring clear and uniform imaging across the entire image range. Thus, by setting the first lens 10, the second lens 20, the third lens 30, the fourth lens 40, the sixth lens 60, and the seventh lens 70 as glass spherical lenses, and setting the fifth lens 50 and the eighth lens 80 as glass aspherical lenses, the optical lens includes six glass spherical lenses and two glass aspherical lenses, enabling the optical lens to achieve high imaging clarity over a wide temperature range while achieving a large aperture and high pixel count.

[0028] Optionally, the focal length F of the optical lens and the total optical length TTL of the optical lens should satisfy the following condition: TTL / F < 5.5. This setting can effectively control the total optical length of the optical lens, resulting in a miniaturized optical lens.

[0029] Optionally, the object-side surface of the first lens 10 is convex, and the image-side surface of the first lens 10 is concave; the object-side surface of the second lens 20 is concave, and the image-side surface of the second lens 20 is concave; the object-side surface of the third lens 30 is convex, and the image-side surface of the third lens 30 is convex; the object-side surface of the fourth lens 40 is convex, and the image-side surface of the fourth lens 40 is either flat or concave; the object-side surface of the fifth lens 50 is convex, and the image-side surface of the fifth lens 50 is concave; the object-side surface of the sixth lens 60 is convex, and the image-side surface of the sixth lens 60 is convex; the object-side surface of the seventh lens 70 is concave, and the image-side surface of the seventh lens 70 is convex; the object-side surface of the eighth lens 80 is concave, and the image-side surface of the eighth lens 80 is convex.

[0030] Specifically, by setting the object-side surface of the first lens 10 to be convex and the image-side surface to be concave, making the first lens 10 a meniscus lens (convex in front and concave in the back), and by setting both the object-side and image-side surfaces of the second lens 20 to be concave, both the object-side and image-side surfaces of the third lens 30 to be convex, and the object-side surface of the fourth lens 40 to be convex and the image-side surface to be either flat or concave, the object-side light rays can be smoothly received into the imaging system, allowing the light rays to enter the lens group after the fourth lens 40 at a smaller incident angle, reducing the proportion of higher-order aberrations, which is beneficial for achieving a large field of view and shortening the overall length of the optical system. Simultaneously, by setting the object-side surface of the fifth lens 50 to be convex and the image-side surface of the fifth lens 50 to be concave, both the object-side and image-side surfaces of the sixth lens 60 to be convex, both the object-side and image-side surfaces of the seventh lens 70 to be concave and the image-side surface of the seventh lens 70 to be convex, and both the object-side and image-side surfaces of the eighth lens 80 to be concave and the image-side surface of the eighth lens 80, the shapes of the lenses complement each other, ensuring that the optical lens has a large aperture and high image sharpness.

[0031] Optionally, the refractive index and dispersion coefficient of the first lens 10 to the eighth lens 80 satisfy the following conditions: 1.45≤n1≤1.65; 55.8≤v1≤80.2; 1.80≤n²≤1.90; 20.90≤v²≤29.90; 1.78≤n3≤1.89; 45.20≤v3≤55.60; 1.90≤n4≤2.00;12.00≤v4≤21.60; 1.45≤n5≤1.55; 31.00≤v5≤60.40; 1.52≤n6≤1.66; 60.90≤v6≤71.30; 1.90≤n7≤2.00; 12.00≤v7≤21.00; 1.69≤n8≤1.92; 21.80≤v8≤42.10; Wherein, n1 is the refractive index of the first lens 10, n2 is the refractive index of the second lens 20, n3 is the refractive index of the third lens 30, n4 is the refractive index of the fourth lens 40, n5 is the refractive index of the fifth lens 50, n6 is the refractive index of the sixth lens 60, n7 is the refractive index of the seventh lens 70, n8 is the refractive index of the eighth lens 80, v1 is the dispersion coefficient of the first lens 10, v2 is the dispersion coefficient of the second lens 20, v3 is the dispersion coefficient of the third lens 30, v4 is the dispersion coefficient of the fourth lens 40, v5 is the dispersion coefficient of the fifth lens 50, v6 is the dispersion coefficient of the sixth lens 60, v7 is the dispersion coefficient of the seventh lens 70, and v8 is the dispersion coefficient of the eighth lens 80.

[0032] As we can understand, the refractive index is the ratio of the speed of light in a vacuum to the speed of light in the medium, primarily used to describe a material's ability to refract light; different materials have different refractive indices. The dispersion coefficient is an index used to represent the dispersion ability of a transparent medium; the more severe the dispersion of the medium, the smaller the dispersion coefficient; conversely, the less severe the dispersion, the larger the dispersion coefficient. Therefore, by carefully configuring the refractive index and dispersion coefficient of each lens in a fixed-focus lens, it is beneficial to achieve higher pixel resolution and a larger aperture.

[0033] Optionally, the second lens 20 and the third lens 30 form a cemented lens. In this case, the image-side surface of the second lens 20 and the object-side surface of the third lens 30 can be supported by a gasket or bonded together with adhesive. By setting the second lens 20 and the third lens 30 to form a cemented lens, chromatic aberration of the optical lens can be effectively corrected, the eccentricity sensitivity of the optical lens can be reduced, and the aberrations of the optical lens can be balanced, thereby improving the imaging quality of the optical lens.

[0034] Optionally, the sixth lens 60 and the seventh lens 70 can form a cemented lens. In this case, the image-side surface of the sixth lens 60 and the object-side surface of the seventh lens 70 can be supported by a gasket or bonded together with adhesive. By setting the sixth lens 60 and the seventh lens 70 to form a cemented lens, chromatic aberration of the optical lens can be effectively corrected, the eccentricity sensitivity of the optical lens can be reduced, and the aberrations of the optical lens can be balanced, thereby improving the imaging quality of the optical lens.

[0035] Optionally, the optical lens may also include an aperture stop 90, which may be located in the optical path between the fourth lens 40 and the fifth lens 50. The aperture stop 90 divides the optical lens into a front lens group and a rear lens group. The front lens group consists of four lenses, from the first lens 10 to the fourth lens 40, and the rear lens group also consists of four lenses, from the fifth lens 50 to the eighth lens 80. The aperture stop 90 may be located near the object side of the fifth lens 50, which can reduce the generation of astigmatism in the optical lens and help to gather the light entering the optical system, thereby reducing the rear aperture of the optical lens.

[0036] Optionally, the entrance pupil diameter (ENPD) of the optical lens and the total optical length (TTL) of the optical lens should satisfy the following ratio: ENPD / TTL > 0.1. This setting allows the optical lens to achieve a large aperture, providing more incident light to the lens.

[0037] Optionally, the entrance pupil diameter ENPD of the optical lens and the image height H corresponding to the maximum field of view of the optical lens must satisfy the condition: H / ENPD < 1.3. This setting allows for a wider beam width entering the optical lens, which is beneficial for the large aperture of the optical lens and better imaging results.

[0038] This embodiment achieves high pixel count, high resolution, large aperture, weak ghosting, and a small overall optical length by rationally allocating parameters such as the material, optical power, and shape of each lens. For example, the overall optical length can be controlled to around 30mm, and it can have high-quality imaging effects. This allows the optical lens to produce photos that meet the 8-megapixel level when applied to an automotive camera.

[0039] Specific embodiments of the optical lens applicable to the above-described embodiments are further described below with reference to the accompanying drawings.

[0040] In one feasible embodiment, Table 1 details a feasible implementation method. Figure 1 The specific optical physical parameters of the optical lens are shown.

[0041] Table 1. Design of one type of optical physical parameters for an optical lens. In this embodiment, the optical lens has a focal length f of 5.507mm, a field of view (FOV) of 100°, and an aperture of F1.46. Table 2 shows the design parameters of the surface type, radius of curvature, thickness, and material of each lens in an optical lens corresponding to Table 1.

[0042] Table 2. Parameter Design of Each Lens in an Optical Lens The optical lens of this embodiment includes a first lens 10, a second lens 20, a third lens 30, a fourth lens 40, an aperture stop 90, a fifth lens 50, a sixth lens 60, a seventh lens 70, an eighth lens 80, and a filter 100 arranged sequentially along the optical axis from the object side to the image side. Wherein, "1" represents the object side of the first lens 10, "2" represents the image side of the first lens 10, and so on; "STO" represents the aperture stop; "IMA" represents the imaging plane of the optical lens; the radius of curvature represents the degree of curvature of the lens surface, with a positive value indicating that the surface bends towards the image plane and a negative value indicating that the surface bends towards the object plane; "PL" indicates that the surface is flat and the radius of curvature is infinite; the thickness represents the axial distance between the current surface and the next surface; the refractive index represents the ability of the material between the current surface and the next surface to deflect light, with a space indicating that the current position is air and the refractive index is 1; the dispersion coefficient represents the dispersion characteristics of the material between the current surface and the next surface, with a space indicating that the current position is air.

[0043] In this embodiment, the fifth lens 50 and the eighth lens 80 are set as aspherical lenses. At this time, the aspherical surface shape equation Z of the fifth lens 50 and the eighth lens 80 satisfies: Where z is the axial sagitta in the Z-direction of the aspherical surface, c is the fundamental curvature at the vertex of the aspherical surface, k is the conic section constant, r is the radial coordinate perpendicular to the optical axis, and a4, a6, a8, a 10 a 12 a 14 a 16 These are the coefficients of the 4th, 6th, 8th, 10th, 12th, 14th, and 16th order terms of the aspherical polynomial, respectively.

[0044] Table 3. Aspherical coefficient of an optical lens. Where 2.571E-004 indicates that the coefficient a4 of face number 9 is 2.571 × 10⁻⁶. -4 And so on.

[0045] Figures 2 to 12 yes Figure 1 The diagram shown illustrates the light fan of the optical lens, as follows: Figures 2 to 12 In the graph, the horizontal axis represents the normalized beam aperture, and the vertical axis represents the transverse aberration. Ideally, each curve should perfectly coincide with the horizontal axis, at which point all rays in the field of view converge at the same point on the image plane. The vertical axis can also represent the maximum dispersion range of the beam on the ideal image plane. The ray fan diagram not only reflects monochromatic aberrations of different wavelengths but also indicates the magnitude of transverse chromatic aberration. Figures 2 to 12 It can be seen that the optical properties of the lens closely approximate the horizontal axis at all wavelengths (436nm, 486nm, 546nm, 587nm, 656nm) across all fields of view (0.00°, 4.87°, 9.37°, 14.62°, 19.52°, 24.46°, 29.43°, 34.46°, 39.54°, 44.64°, 49.76°), indicating that the transverse aberrations at each wavelength (436nm, 486nm, 546nm, 587nm, 656nm) are well corrected. Furthermore, the curves for each color do not show significant dispersion, indicating that the optical system of the lens also provides good correction for chromatic aberration, meeting the requirements for the use of optical lenses.

[0046] Figure 13 yes Figure 1 The diagram shows the axial aberration curve of the optical lens. Figure 13 In this diagram, the vertical direction represents the normalized aperture, 0 indicates it is on the optical axis, and the vertical vertex represents the maximum pupil radius; the horizontal direction represents the offset relative to the ideal focal point, in millimeters (mm). For example... Figure 13 As shown, different linear curves represent the different wavelengths (436nm, 486nm, 546nm, 587nm, 656nm) imaged by the optical system of the optical lens. Figure 13It can be seen that the axial aberrations at different wavelengths (436nm, 486nm, 546nm, 587nm, 656nm) are all controlled within the range of (-0.05mm, +0.05mm), indicating that the spherical aberration of the optical lens at each wavelength (436nm, 486nm, 546nm, 587nm, 656nm) is well controlled, which can meet the requirements of broadband applications.

[0047] Figure 14 yes Figure 1 The schematic diagram of the field curvature distortion curve of the optical lens is shown below. Figure 14 As shown, in the coordinate system on the left, the horizontal coordinate represents the magnitude of the field curvature, in mm; the vertical coordinate represents the normalized image height, which has no unit; from Figure 14 It can be seen that light of different wavelengths (436nm, 486nm, 546nm, 587nm, 656nm) is effectively controlled in terms of field curvature, that is, during imaging, the difference between the image quality at the center and the image quality at the periphery is small; in the coordinate system on the right, the horizontal coordinate represents the magnitude of distortion in %; the vertical coordinate represents the normalized image height, which has no unit.

[0048] In another feasible embodiment, Figure 15 This is a schematic diagram of another optical lens structure provided in an embodiment of the present invention. Table 4 describes in detail another feasible implementation. Figure 15 The specific optical physical parameters of the optical lens are shown.

[0049] Table 4. Another optical physical parameter design for optical lenses In this embodiment, the optical lens has a focal length f of 5.504mm, a field of view (FOV) of 100°, and an aperture of F1.46. Table 5 shows the design parameters of the surface type, radius of curvature, thickness, and material of each lens in an optical lens corresponding to Table 4.

[0050] Table 5. Another parameter design for each lens in an optical lens. The optical lens of this embodiment includes a first lens 10, a second lens 20, a third lens 30, a fourth lens 40, an aperture stop 90, a fifth lens 50, a sixth lens 60, a seventh lens 70, an eighth lens 80, and a filter 100 arranged sequentially along the optical axis from the object side to the image side. Wherein, "1" represents the object side of the first lens 10, "2" represents the image side of the first lens 10, and so on; "STO" represents the aperture stop; "IMA" represents the imaging plane of the optical lens; the radius of curvature represents the degree of curvature of the lens surface, with a positive value indicating that the surface bends towards the image plane and a negative value indicating that the surface bends towards the object plane; "PL" indicates that the surface is flat and the radius of curvature is infinite; the thickness represents the axial distance between the current surface and the next surface; the refractive index represents the ability of the material between the current surface and the next surface to deflect light, with a space indicating that the current position is air and the refractive index is 1; the dispersion coefficient represents the dispersion characteristics of the material between the current surface and the next surface, with a space indicating that the current position is air.

[0051] In this embodiment, the fifth lens 50 and the eighth lens 80 are set as aspherical lenses. At this time, the aspherical surface shape equation Z of the fifth lens 50 and the eighth lens 80 satisfies: Where z is the axial sagitta in the Z-direction of the aspherical surface, c is the fundamental curvature at the vertex of the aspherical surface, k is the conic section constant, r is the radial coordinate perpendicular to the optical axis, and a4, a6, a8, a 10 a 12 a 14 a 16 These are the coefficients of the 4th, 6th, 8th, 10th, 12th, 14th, and 16th order terms of the aspherical polynomial, respectively.

[0052] Table 6. Another aspherical coefficient for optical lenses. Where 2.272E-004 indicates that the coefficient a4 of face number 9 is 2.272 × 10⁻⁶. -4 And so on.

[0053] Figures 16 to 26 yes Figure 15 The diagram shown illustrates the light fan of the optical lens, as follows: Figures 16 to 26 In the graph, the horizontal axis represents the normalized beam aperture, and the vertical axis represents the transverse aberration. Ideally, each curve should perfectly coincide with the horizontal axis, at which point all rays in the field of view converge at the same point on the image plane. The vertical axis can also represent the maximum dispersion range of the beam on the ideal image plane. The ray fan diagram not only reflects monochromatic aberrations of different wavelengths but also indicates the magnitude of transverse chromatic aberration. Figures 16 to 26It can be seen that the optical properties of the lens closely approximate the horizontal axis at all wavelengths (436nm, 486nm, 546nm, 587nm, 656nm) across all fields of view (0.00°, 4.87°, 9.74°, 14.62°, 19.52°, 24.46°, 29.43°, 34.46°, 39.54°, 44.64°, 49.76°), indicating that the transverse aberrations at each wavelength (436nm, 486nm, 546nm, 587nm, 656nm) are well corrected. Furthermore, the curves for each color do not show significant dispersion, indicating that the optical system of the lens also provides good correction for chromatic aberration, meeting the requirements for the use of optical lenses.

[0054] Figure 27 yes Figure 15 The diagram shows the axial aberration curve of the optical lens. Figure 27 In this diagram, the vertical direction represents the normalized aperture, 0 indicates it is on the optical axis, and the vertical vertex represents the maximum pupil radius; the horizontal direction represents the offset relative to the ideal focal point, in millimeters (mm). For example... Figure 27 As shown, different linear curves represent the different wavelengths (436nm, 486nm, 546nm, 587nm, 656nm) imaged by the optical system of the optical lens. Figure 27 It can be seen that the axial aberrations at different wavelengths (436nm, 486nm, 546nm, 587nm, 656nm) are all controlled within the range of (-0.05mm, +0.05mm), indicating that the spherical aberration of the optical lens at each wavelength (436nm, 486nm, 546nm, 587nm, 656nm) is well controlled, which can meet the requirements of broadband applications.

[0055] Figure 28 yes Figure 15 The schematic diagram of the field curvature distortion curve of the optical lens is shown below. Figure 28 As shown, in the coordinate system on the left, the horizontal coordinate represents the magnitude of the field curvature, in mm; the vertical coordinate represents the normalized image height, which has no unit; from Figure 28 It can be seen that light of different wavelengths (436nm, 486nm, 546nm, 587nm, 656nm) is effectively controlled in terms of field curvature, that is, during imaging, the difference between the image quality at the center and the image quality at the periphery is small; in the coordinate system on the right, the horizontal coordinate represents the magnitude of distortion in %; the vertical coordinate represents the normalized image height, which has no unit.

[0056] In yet another feasible embodiment, Figure 29 This is a schematic diagram of another optical lens provided in the embodiments of the present invention. Table 7 describes in detail another feasible implementation. Figure 29 The specific optical physical parameters of the optical lens are shown.

[0057] Table 7 Another optical physical parameter design for optical lenses In this embodiment, the optical lens has a focal length f of 5.524mm, a field of view (FOV) of 100°, and an aperture of F1.46. Table 8 shows the design parameters of the surface type, radius of curvature, thickness, and material of each lens in another type of optical lens corresponding to Table 7.

[0058] Table 8 Another parameter design for each lens in an optical lens The optical lens of this embodiment includes a first lens 10, a second lens 20, a third lens 30, a fourth lens 40, an aperture stop 90, a fifth lens 50, a sixth lens 60, a seventh lens 70, an eighth lens 80, and a filter 100 arranged sequentially along the optical axis from the object side to the image side. Wherein, "1" represents the object side of the first lens 10, "2" represents the image side of the first lens 10, and so on; "STO" represents the aperture stop; "IMA" represents the imaging plane of the optical lens; the radius of curvature represents the degree of curvature of the lens surface, with a positive value indicating that the surface bends towards the image plane and a negative value indicating that the surface bends towards the object plane; "PL" indicates that the surface is flat and the radius of curvature is infinite; the thickness represents the axial distance between the current surface and the next surface; the refractive index represents the ability of the material between the current surface and the next surface to deflect light, with a space indicating that the current position is air and the refractive index is 1; the dispersion coefficient represents the dispersion characteristics of the material between the current surface and the next surface, with a space indicating that the current position is air.

[0059] In this embodiment, the fifth lens 50 and the eighth lens 80 are set as aspherical lenses. At this time, the aspherical surface shape equation Z of the fifth lens 50 and the eighth lens 80 satisfies: Where z is the axial sagitta in the Z-direction of the aspherical surface, c is the fundamental curvature at the vertex of the aspherical surface, k is the conic section constant, r is the radial coordinate perpendicular to the optical axis, and a4, a6, a8, a 10 a 12 a 14 a 16 These are the coefficients of the 4th, 6th, 8th, 10th, 12th, 14th, and 16th order terms of the aspherical polynomial, respectively.

[0060] Table 9. Another type of aspherical coefficient for optical lenses. Where 1.856E-004 indicates that the coefficient a4 of face number 9 is 1.856 × 10⁻⁶. -4 And so on.

[0061] Figures 30 to 40 yes Figure 29 The diagram shown illustrates the light fan of the optical lens, as follows: Figures 30 to 40 In the graph, the horizontal axis represents the normalized beam aperture, and the vertical axis represents the transverse aberration. Ideally, each curve should perfectly coincide with the horizontal axis, at which point all rays in the field of view converge at the same point on the image plane. The vertical axis can also represent the maximum dispersion range of the beam on the ideal image plane. The ray fan diagram not only reflects monochromatic aberrations of different wavelengths but also indicates the magnitude of transverse chromatic aberration. Figures 30 to 40 It can be seen that the optical lens's optics closely approximate the horizontal axis at all wavelengths (436nm, 486nm, 546nm, 587nm, 656nm) across all fields of view (0.00°, 4.87°, 9.74°, 14.62°, 19.52°, 24.46°, 29.43°, 34.46°, 39.54°, 44.64°, 50.00°), indicating that the transverse aberrations at each wavelength (436nm, 486nm, 546nm, 587nm, 656nm) are well corrected. Furthermore, the curves for each color do not show significant dispersion, indicating that the optical system of the lens also provides good correction for chromatic aberration, meeting the requirements for the use of optical lenses.

[0062] Figure 41 yes Figure 29 The diagram shows the axial aberration curve of the optical lens. Figure 41 In this diagram, the vertical direction represents the normalized aperture, 0 indicates it is on the optical axis, and the vertical vertex represents the maximum pupil radius; the horizontal direction represents the offset relative to the ideal focal point, in millimeters (mm). For example... Figure 41 As shown, different linear curves represent the different wavelengths (436nm, 486nm, 546nm, 587nm, 656nm) imaged by the optical system of the optical lens. Figure 41 It can be seen that the axial aberrations at different wavelengths (436nm, 486nm, 546nm, 587nm, 656nm) are all controlled within the range of (-0.05mm, +0.05mm), indicating that the spherical aberration of the optical lens at each wavelength (436nm, 486nm, 546nm, 587nm, 656nm) is well controlled, which can meet the requirements of broadband applications.

[0063] Figure 42 yes Figure 29 The schematic diagram of the field curvature distortion curve of the optical lens is shown below. Figure 42 As shown, in the coordinate system on the left, the horizontal coordinate represents the magnitude of the field curvature, in mm; the vertical coordinate represents the normalized image height, which has no unit; from Figure 42It can be seen that light of different wavelengths (436nm, 486nm, 546nm, 587nm, 656nm) is effectively controlled in terms of field curvature, that is, during imaging, the difference between the image quality at the center and the image quality at the periphery is small; in the coordinate system on the right, the horizontal coordinate represents the magnitude of distortion in %; the vertical coordinate represents the normalized image height, which has no unit.

[0064] Based on the same inventive concept, embodiments of the present invention also provide a vehicle-mounted camera, which includes the optical lens provided in any embodiment of the present invention. Therefore, this vehicle-mounted camera possesses the technical features of the optical lens provided in the embodiments of the present invention and can achieve the beneficial effects of the optical lens provided in the embodiments of the present invention. Similarities can be found in the above description of the optical lens provided in the embodiments of the present invention, and will not be repeated here.

[0065] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.

Claims

1. An optical lens, characterized in that, include: The first lens, second lens, third lens, fourth lens, fifth lens, sixth lens, seventh lens and eighth lens are arranged sequentially along the optical axis from the object side to the image side; The first lens has negative optical power, the second lens has negative optical power, the third lens has positive optical power, the fourth lens has positive optical power, the fifth lens has positive optical power, the sixth lens has positive optical power, the seventh lens has negative optical power, and the eighth lens has negative optical power. The first lens, the second lens, the third lens, the fourth lens, the sixth lens, and the seventh lens are all spherical glass lenses; the fifth lens and the eighth lens are aspherical glass lenses. The focal length F of the optical lens and the total optical length TTL of the optical lens satisfy the following condition: TTL / F < 5.

5.

2. The optical lens according to claim 1, characterized in that, The object-side surface of the first lens is convex, and the image-side surface of the first lens is concave. The object-side surface of the second lens is concave, and the image-side surface of the second lens is also concave. The object-side surface of the third lens is convex, and the image-side surface of the third lens is convex. The object-side surface of the fourth lens is convex, and the image-side surface of the fourth lens is either flat or concave. The object-side surface of the fifth lens is convex, and the image-side surface of the fifth lens is concave. The object-side surface of the sixth lens is convex, and the image-side surface of the sixth lens is convex. The object-side surface of the seventh lens is concave, and the image-side surface of the seventh lens is convex. The object-side surface of the eighth lens is concave, and the image-side surface of the eighth lens is convex.

3. The optical lens according to claim 1, characterized in that, The optical power of the first lens to the eighth lens satisfies the following condition: -0.15≤Φ1 / Φ≤-0.05; -0.27≤Φ2 / Φ≤-0.17; 0.10≤Φ3 / Φ≤0.20; 0.02≤Φ4 / Φ≤0.12; 0.02≤Φ5 / Φ≤0.088; 0.10≤Φ6 / Φ≤0.20; -0.16≤Φ7 / Φ≤-0.05; -0.05≤Φ8 / Φ≤0.05; Wherein, Φ is the optical power of the optical lens, Φ1 is the optical power of the first lens, Φ2 is the optical power of the second lens, Φ3 is the optical power of the third lens, Φ4 is the optical power of the fourth lens, Φ5 is the optical power of the fifth lens, Φ6 is the optical power of the sixth lens, Φ7 is the optical power of the seventh lens, and Φ8 is the optical power of the eighth lens.

4. The optical lens according to claim 1, characterized in that, The refractive index and dispersion coefficient of the first lens to the eighth lens satisfy the following conditions: 1.45≤n1≤1.65; 55.8≤v1≤80.2; 1.80≤n²≤1.90; 20.90≤v²≤29.90; 1.78≤n3≤1.89; 45.20≤v3≤55.60; 1.90≤n4≤2.00;12.00≤v4≤21.60; 1.45≤n5≤1.55; 31.00≤v5≤60.40; 1.52≤n6≤1.66; 60.90≤v6≤71.30; 1.90≤n7≤2.00; 12.00≤v7≤21.00; 1.69≤n8≤1.92; 21.80≤v8≤42.10; Wherein, n1 is the refractive index of the first lens, n2 is the refractive index of the second lens, n3 is the refractive index of the third lens, n4 is the refractive index of the fourth lens, n5 is the refractive index of the fifth lens, n6 is the refractive index of the sixth lens, n7 is the refractive index of the seventh lens, n8 is the refractive index of the eighth lens, v1 is the dispersion coefficient of the first lens, v2 is the dispersion coefficient of the second lens, v3 is the dispersion coefficient of the third lens, v4 is the dispersion coefficient of the fourth lens, v5 is the dispersion coefficient of the fifth lens, v6 is the dispersion coefficient of the sixth lens, v7 is the dispersion coefficient of the seventh lens, and v8 is the dispersion coefficient of the eighth lens.

5. The optical lens according to claim 1, characterized in that, The second lens and the third lens together form a cemented lens.

6. The optical lens according to claim 1, characterized in that, The sixth and seventh lenses together form a cemented lens.

7. The optical lens according to claim 1, characterized in that, Also includes: Aperture; the aperture is located in the optical path between the fourth lens and the fifth lens.

8. The optical lens according to claim 1, characterized in that, The entrance pupil diameter ENPD of the optical lens and the total optical length TTL of the optical lens satisfy the following condition: ENPD / TTL > 0.

1.

9. The optical lens according to claim 1, characterized in that, The entrance pupil diameter ENPD of the optical lens and the image height H of the optical lens at the maximum field of view satisfy the following condition: H / ENPD < 1.

3.

10. A vehicle-mounted camera, characterized in that, include: The optical lens according to any one of claims 1-9.

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