An optical lens

Abstract

The utility model discloses an optical lens, including first lens, second lens, third lens, fourth lens, fifth lens, sixth lens and seventh lens that arrange in proper order from object plane to image plane along the optical axis, first lens, second lens and fifth lens are all negative focal power, and third lens, fourth lens, sixth lens and seventh lens are all positive focal power, first lens is convex-concave lens, second lens is concave-convex lens, third lens is double convex lens, fourth lens is convex-concave lens or convex-flat lens, fifth lens is convex-concave lens, sixth lens is double convex lens, and seventh lens is convex-concave lens, the curvature radius of object side surface of first lens is R1, the curvature radius of image side surface of fourth lens is R9, and the focal length of optical lens is F, wherein: 4 < R1 / F < 6, and R9 / F > 18. Guarantee the premise of high performance, miniaturization, improve ghost image suppression ability and imaging quality, satisfy the demand of high definition image quality.

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 the development of autonomous driving assistance systems, the performance requirements of vehicle side-view cameras have significantly increased. However, in practical applications, they face many technical challenges: limited installation space makes it difficult for existing lenses to balance miniaturization and concealment, resulting in poor adaptability; the need to cover a wide range of side environments means that existing lenses have insufficient field of view, easily creating blind spots; in terms of safety, weak ghosting suppression can lead to machine misjudgment, and poor chromatic aberration correction affects the resolution of colored objects; insufficient environmental adaptability results in low light transmission and poor imaging under low light conditions, and poor thermal stability and reduced resolution after high and low temperature cycling; and the difficulty in balancing performance with cost and lightweight requirements restricts large-scale application. Therefore, the market currently needs an optical lens that is high-pixel, miniaturized, high-definition, with weak ghosting, a wide field of view, and good environmental adaptability. Utility Model Content

[0003] This invention provides an optical lens that, while ensuring high performance and miniaturization, improves ghosting suppression and imaging quality, thus meeting the requirements for high-definition image quality.

[0004] This utility model provides 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, and a seventh lens arranged sequentially along the optical axis from the object plane to the image plane;

[0005] 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 negative optical power, the sixth lens has positive optical power, and the seventh lens has positive optical power.

[0006] The surface of the lens adjacent to the object plane is called the object-side surface, and the surface of the lens adjacent to the image plane is called the image-side surface; the object-side surface of the first lens is convex, and the image-side surface is concave; the object-side surface of the second lens is concave, and the image-side surface is convex; the object-side surface of the third lens is convex, and the image-side surface is convex; the object-side surface of the fourth lens is convex, and the image-side surface is either flat or concave; the object-side surface of the fifth lens is convex, and the image-side surface is concave; the object-side surface of the sixth lens is convex, and the image-side surface is convex; the central region of the object-side surface of the seventh lens is convex, and the central region of the image-side surface is concave.

[0007] The object-side radius of curvature of the first lens is R1, the image-side radius of curvature of the fourth lens is R9, and the focal length of the optical lens is F, wherein: 4 < R1 / F < 6; R9 / F > 18.

[0008] Optionally, 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, and the focal length of the seventh lens is f7, wherein:

[0009] -2 <f1 / F<0; -30<f2 / F<0; 1.8<f3 / F<3; 2<f4 / F<5; -2<f5 / F<0; 0<f6 / F<2;0<f7 / F<60。

[0010] Optionally, the fifth lens and the sixth lens are cemented together to form a cemented lens group, the focal length of the cemented lens group is f56, and the focal length of the optical lens is F, wherein: 10≤|f56 / F|≤80.

[0011] Optionally, the first lens has a refractive index of nd1 and an Abbe number of vd1; the second lens has a refractive index of nd2 and an Abbe number of vd2; the third lens has a refractive index of nd3 and an Abbe number of vd3; the fourth lens has a refractive index of nd4 and an Abbe number of vd4; the fifth lens has a refractive index of nd5 and an Abbe number of vd5; the sixth lens has a refractive index of nd6 and an Abbe number of vd6; and the seventh lens has a refractive index of nd7 and an Abbe number of vd7; wherein:

[0012] 1.75≤nd1≤1.92; 30.0≤vd1≤55.0;

[0013] 1.47≤nd2≤1.65; 43.3≤vd2≤68.0;

[0014] 1.83≤nd3≤1.96; 24.3≤vd3≤35.8;

[0015] 1.43≤nd4≤1.73; 48.0≤vd4≤72.6;

[0016] 1.85≤nd5≤2.05; 15.3≤vd5≤35.6;

[0017] 1.52≤nd6≤1.71; 53.2≤vd6≤68.0;

[0018] 1.45≤nd7≤1.80; 20.0≤vd7≤68.0.

[0019] Optionally, the optical aperture of the object side of the first lens is D, and the image height corresponding to the maximum field of view of the optical lens is ImgH, where: 1.2≤D / ImgH≤1.8.

[0020] Optionally, the total optical length of the optical lens is TTL, and the optical back focal length of the optical lens is BFL, wherein BFL / TTL≥0.1.

[0021] Optionally, the total optical length of the optical lens is TTL, and the entrance pupil diameter of the optical lens is ENPD, wherein: ENPD / TTL > 0.3.

[0022] Optionally, the optical power of the second lens is φ2, and the optical power of the seventh lens is φ7, wherein -5 < φ2 / φ7 < -1.

[0023] Optionally, the first lens, the third lens, the fourth lens, the fifth lens, and the sixth lens are all glass spherical lenses; the second lens and the seventh lens are both plastic aspherical lenses.

[0024] Optionally, the optical lens further includes an aperture stop disposed in the optical path between the second lens and the third lens.

[0025] The technical solution of this utility model embodiment includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens arranged sequentially along the optical axis from the object plane to the image plane. By reasonably setting the optical power, surface shape, and lens surface radius of each lens and the focal length of the optical system, an optical lens with high pixel count, miniaturization, high definition, large aperture, weak ghosting, low temperature drift, total length within 22mm, and low cost can be achieved.

[0026] 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

[0027] 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.

[0028] Figure 1 A schematic diagram of the structure of an optical lens provided in an embodiment of this utility model;

[0029] Figure 2 A ray fan pattern of an optical lens provided in Embodiment 1 of this utility model;

[0030] Figure 3An MTF diagram of an optical lens provided in Embodiment 1 of this utility model;

[0031] Figure 4 An axial aberration curve of an optical lens is provided for Embodiment 1 of this utility model;

[0032] Figure 5 This is a schematic diagram of the structure of an optical lens provided in Embodiment 2 of this utility model;

[0033] Figure 6 This is a light fan pattern of an optical lens provided in Embodiment 2 of the present invention;

[0034] Figure 7 An MTF diagram of an optical lens provided in Embodiment 2 of this utility model;

[0035] Figure 8 This invention provides an axial aberration curve diagram of an optical lens according to Embodiment 2 of the present invention.

[0036] Figure 9 This is a schematic diagram of the structure of an optical lens provided in Embodiment 3 of this utility model;

[0037] Figure 10 A light fan pattern of an optical lens provided in Embodiment 3 of this utility model;

[0038] Figure 11 An MTF diagram of an optical lens provided in Embodiment 3 of this utility model;

[0039] Figure 12 This invention provides an axial aberration curve of an optical lens according to Embodiment 3 of the present invention. Detailed Implementation

[0040] 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.

[0041] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the utility model described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0042] Figure 1 This is a schematic diagram of the structure of an optical lens provided in an embodiment of the present invention, 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, and a seventh lens 107 arranged sequentially along the optical axis from the object plane to the image plane; the first lens 101 has negative optical power, the second lens 102 has negative optical power, the third lens 103 has positive optical power, the fourth lens 104 has positive optical power, the fifth lens 105 has negative optical power, the sixth lens 106 has positive optical power, and the seventh lens 107 has positive optical power; the surface of the lens adjacent to the object plane is the object-side surface, and the surface of the lens adjacent to the image plane is the image-side surface; the object-side surface of the first lens 101 is convex, and the image-side surface is concave; the object-side surface of the second lens 102 is concave, and the image-side surface is convex; the object-side surface of the third lens 103 is convex, and the image-side surface is convex; the first lens 101 has a first lens 101, a second lens 102, a third lens 103, a fourth lens 104, a fifth lens 105, a sixth lens 106, and a seventh lens 107. The object-side surface of the fourth lens 104 is convex, and the image-side surface is either flat or concave; the object-side surface of the fifth lens 105 is convex, and the image-side surface is concave; the object-side surface of the sixth lens 106 is convex, and the image-side surface is convex; the central region of the object-side surface of the seventh lens 107 is convex, and the central region of the image-side surface is concave; the radius of curvature of the object-side surface of the first lens 101 is R1, the radius of curvature of the image-side surface of the fourth lens 104 is R9, and the focal length of the optical lens is F, where: 4 < R1 / F < 6; R9 / F > 18.

[0043] Optical power is equal to the difference between the convergence of the image-side beam and the convergence of the object-side beam, characterizing the ability of an optical system to deflect light. The larger the absolute value of the optical power, the stronger the bending ability of light; the smaller the absolute value, the weaker the bending ability. When the optical power is positive, the refraction of light is converging; when the optical power is negative, the refraction of light is diverging. Optical power can be used to characterize a single refractive surface of a lens (i.e., one surface of the lens), a single lens, or a system formed by multiple lenses (i.e., a lens group). In the optical lens provided in this embodiment, each lens can be fixed to a single lens barrel (…). Figure 1 (Not shown in the image) Within the lens, the first lens 101 and the second lens 102 both have negative optical power, used to control the incident angle of light in the optical system. This helps to mitigate large incident angles, ensuring a large field of view, and also corrects aberrations. The third lens 103 and the fourth lens 104 both have positive optical power, used to focus the front beam. The negative optical power of the front group corrects the aberrations of the positive optical power of the rear group, and plays a crucial role in preventing focus shift at high and low temperatures. They also help reduce the aperture and overall length of the optical lens, facilitating miniaturization. The fifth lens 105 has negative optical power, and the sixth lens 106 has positive optical power, used to correct off-axis aberrations, including field curvature, coma, and astigmatism. The seventh lens 107 has positive optical power, causing light to converge to the image plane, effectively improving astigmatism and field curvature of the optical lens, and enhancing the resolving power of the optical lens.

[0044] The surface of a lens adjacent to the object plane is called the object-side surface, and the surface of the lens adjacent to the image plane is called the image-side surface. The object-side surface of the first lens 101 is convex, and the image-side surface is concave. The object-side surface of the second lens 102 is concave, and the image-side surface is convex. The object-side surface of the third lens 103 is convex, and the image-side surface is convex. The object-side surface of the fourth lens 104 is convex, and the image-side surface is either flat or concave. The object-side surface of the fifth lens 105 is convex, and the image-side surface is concave. The object-side surface of the sixth lens 106 is convex, and the image-side surface is convex. The central region of the object-side surface of the seventh lens 107 is convex, and the central region of the image-side surface is concave. For example, as shown... Figure 1 As shown, the first lens 101 is a meniscus lens, and the object-side surface of the fourth lens 104 is convex, while the image-side surface is flat. By reasonably setting the surface shape of each lens, the optical power and focal length of each lens can meet the requirements of the above embodiments, while also ensuring that the entire optical lens structure is compact and highly integrated.

[0045] The object-side radius of curvature of the first lens 101 is R1, the image-side radius of curvature of the fourth lens 104 is R9, and the focal length of the optical lens is F, where: 4 < R1 / F < 6; R9 / F > 18. By setting the object-side radius of curvature R1 of the first lens 101 and the focal length F of the optical lens to satisfy: 4 < R1 / F < 6, the object-side radius of curvature of the first lens 101 is controlled. Within this range, the object-side light rays can be smoothly received into the imaging system, while reducing the front aperture of the lens. Furthermore, setting the image-side radius of curvature R9 of the fourth lens 104 and the overall focal length F of the optical lens to satisfy: R9 / F > 18, the assembly sensitivity of the optical lens can be reduced, thereby reducing the manufacturing difficulty of the optical lens, improving the assembly yield of the optical lens, changing the relative position and size of the secondary reflection ghost image on the image plane of the image-side of the fourth lens 104, effectively reducing the relative energy value of the ghost image, and achieving the requirement of weak ghost image.

[0046] Optionally, the focal length of the first lens 101 is f1, the focal length of the second lens 102 is f2, the focal length of the third lens 103 is f3, the focal length of the fourth lens 104 is f4, the focal length of the fifth lens 105 is f5, the focal length of the sixth lens 106 is f6, and the focal length of the seventh lens 107 is f7, where: -2 <f1 / F<0; -30<f2 / F<0; 1.8<f3 / F<3; 2<f4 / F<5; -2<f5 / F<0; 0<f6 / F<2; 0<f7 / F<60。

[0047] Wherein, by setting that the focal length f1 of the first lens 101 and the focal length F of the optical lens satisfy -2 < f1 / F < 0, the first lens 101 has appropriate negative power, which can capture light entering the optical lens at a large angle, is beneficial to expanding the field of view of the optical lens, and is also conducive to reducing the sensitivity of the optical lens and realizing the miniaturization design of the optical lens. By setting that the focal length f2 of the second lens 102 and the focal length F of the optical lens satisfy -30 < f2 / F < 0, the second lens 102 has appropriate negative power, which is beneficial to the smooth transition of light, facilitates the correction of astigmatism and field curvature, and improves the imaging quality of the optical lens. By setting that the focal length f3 of the third lens 103 and the focal length F of the optical lens satisfy 1.8 < f3 / F < 3, controlling the focal length of the third lens 103 to adjust the traveling trend of light, which is beneficial to the convergence of light, facilitates the correction of astigmatism and field curvature, and improves the imaging quality of the optical lens. By setting that the focal length f4 of the fourth lens 104 and the focal length F of the optical lens satisfy 2 < f4 / F < 5, the fourth lens 104 has appropriate positive power, which is beneficial to achieving good temperature characteristics and ensuring that the lens can still maintain good imaging quality under high and low temperature conditions. By setting that the focal length f5 of the fifth lens 105 and the focal length F of the optical lens satisfy -2 < f5 / F < 0, the fifth lens 105 has appropriate negative power, which is beneficial to balancing various aberrations generated by the fifth lens 105 and improving the imaging quality of the optical lens. By setting that the focal length f6 of the sixth lens 106 and the focal length F of the optical lens satisfy 0 < f6 / F < 2, the sixth lens 106 has appropriate positive power, which is beneficial to balancing various aberrations generated by the sixth lens 106 and improving the imaging quality of the optical lens. By setting that the focal length f7 of the seventh lens 107 and the focal length F of the optical lens satisfy 0 < f7 / F < 60, the seventh lens 107 has appropriate positive power, which is beneficial to the smooth transition of light, balances various aberrations generated by the overall lens group, and improves the imaging quality of the optical lens.

[0048] Optionally, the fifth lens 105 and the sixth lens 106 are cemented to form a cemented lens group, the focal length of the cemented lens group is f56, and the focal length of the optical lens is F, wherein: 10 ≤ |f56 / F| ≤ 80.

[0049] By using a cemented lens group consisting of a fifth lens 105 and a sixth lens 106—that is, cementing the image-side surface of the fifth lens 105 and the object-side surface of the sixth lens 106—the air gap between the fifth lens 105 and the sixth lens 106 can be effectively reduced, thereby further reducing the overall length of the lens. Furthermore, the cemented lens group can minimize or eliminate chromatic aberration, allowing various aberrations of the optical lens to be fully corrected. With a compact structure, it can improve resolution, optimize optical performance such as distortion, and reduce light loss caused by reflections between lens elements, thus improving illumination and enhancing image quality and the sharpness of the lens image. In addition, the use of a cemented lens group can reduce the number of assembly components between the two lens elements, simplifying the assembly process in lens manufacturing, reducing costs, and reducing tolerance sensitivity issues such as tilting / eccentricity of lens units during assembly. By properly setting the fifth lens 105 and the sixth lens 106 to cement together to form a cemented lens group and the focal length of the optical lens to satisfy 10≤|f56 / F|≤80, the chromatic aberration of the optical lens can be effectively corrected, the eccentricity sensitivity of the optical lens can be reduced, and the imaging quality of the optical lens can be improved.

[0050] Optionally, the first lens 101 has a refractive index of nd1 and an Abbe number of vd1; the second lens 102 has a refractive index of nd2 and an Abbe number of vd2; the third lens 103 has a refractive index of nd3 and an Abbe number of vd3; the fourth lens 104 has a refractive index of nd4 and an Abbe number of vd4; the fifth lens 105 has a refractive index of nd5 and an Abbe number of vd5; the sixth lens 106 has a refractive index of nd6 and an Abbe number of vd6; and the seventh lens 107 has a refractive index of nd7 and an Abbe number of vd7; wherein: 1.75 ≤ nd1 ≤ 1 0.92; 30.0≤vd1≤55.0; 1.47≤nd2≤1.65; 43.3≤vd2≤68.0; 1.83≤nd3≤1.96; 24.3≤vd3≤35.8; 1.43≤nd4≤1.73; 48.0≤vd4≤72.6; 1.85≤nd5≤2.05; 15.3≤vd5≤35.6; 1.52≤nd6≤1.71; 53.2≤vd6≤68.0; 1.45≤nd7≤1.80; 20.0≤vd7≤68.0.

[0051] 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 Abbe number is an index used to represent the dispersion ability of a transparent medium; the more severe the dispersion, the smaller the Abbe number; conversely, the less severe the dispersion, the larger the Abbe number. Thus, by adjusting the refractive index and Abbe number of each lens in an optical lens, chromatic aberration can be corrected to a significant extent, effectively eliminating chromatic aberration and facilitating miniaturization of the lens design. Simultaneously, it helps achieve higher pixel resolution and a larger aperture, as well as ensuring a balance in the angle of incidence between the front and rear lens elements, reducing lens sensitivity and increasing production feasibility.

[0052] Optionally, the optical aperture of the object side of the first lens 101 is D, and the image height corresponding to the maximum field of view of the optical lens is ImgH, where: 1.2≤D / ImgH≤1.8.

[0053] By satisfying 1.2≤D / ImgH≤1.8 between the optical aperture D of the object side of the first lens 101 and the image height ImgH corresponding to the maximum field of view of the optical lens, it is beneficial to the miniaturization design of the optical system of the optical lens. At the same time, it is also beneficial to the optical system of the optical lens to have the characteristics of high pixel and high resolution, thereby enabling the optical lens to meet the requirements of high imaging quality.

[0054] Optionally, the total optical length of the optical lens is TTL, and the optical back focal length is BFL, where BFL / TTL ≥ 0.1. For example, the total optical length TTL can be understood as the distance from the center of the optical axis on the object side of the first lens 101 to the image plane, and the back focal length BFL can be understood as the distance from the center of the optical axis on the image side of the seventh lens 107 to the image plane. By reasonably setting the relationship between the back focal length BFL and the total optical length TTL, the entire optical lens structure can be ensured to be compact, with high integration. Furthermore, while achieving miniaturization, the long back focal length facilitates module assembly.

[0055] Optionally, the total optical length of the optical lens is TTL, and the entrance pupil diameter is ENPD, where ENPD / TTL > 0.3. The entrance pupil diameter ENPD can be understood as the equivalent aperture formed after light enters the optical system and undergoes refraction or reflection. ENPD determines how much light the optics can collect, directly affecting image brightness and resolution. The total optical length TTL can be understood as the distance from the object side of the first lens 101 to the image plane. By reasonably controlling the ratio of the entrance pupil diameter ENPD to the total optical length TTL to be greater than 0.3, the beam diameter of the incident light can be controlled, increasing the field of view and light intake of the optical lens, effectively compressing the size of the optical lens, achieving lens miniaturization, while simultaneously improving image brightness and resolution, ensuring the lens's large aperture characteristics, and providing more incident light to the optical lens.

[0056] Optionally, the first lens 101, the third lens 103, the fourth lens 104, the fifth lens 105 and the sixth lens 106 are all glass spherical lenses; the second lens 102 and the seventh lens 107 are both plastic aspherical lenses.

[0057] In this embodiment, the first lens 101, the third lens 103, the fourth lens 104, the fifth lens 105, and the sixth lens 106 are all glass spherical lenses to better correct chromatic aberration and aberrations, thereby improving image quality. The second lens 102 and the seventh lens 107 are both plastic aspherical lenses, but this is not a limitation. Since the cost of plastic lenses is much lower than that of glass lenses, the cost of the optical lens can be reduced. At the same time, glass and plastic can compensate for each other, balancing high and low temperatures and reducing the overall length of the lens, giving the optical lens stable performance at high and low temperatures and improving its environmental adaptability. The plastic aspherical lens can be made of various plastics known to those skilled in the art, and the glass spherical lens can be made of various types of glass known to those skilled in the art; this embodiment does not elaborate on or limit the specific materials used.

[0058] Optionally, the optical power of the second lens 102 is φ2, and the optical power of the seventh lens 107 is φ7, where -5 < φ2 / φ7 < -1. Since both the second lens 102 and the seventh lens 107 are plastic aspherical lenses, which are greatly affected by temperature changes, controlling the mutual compensation of the optical power of the two aspherical lenses can reduce the back focus shift of the optical lens after temperature changes, achieving a low-temperature drift effect.

[0059] Optionally, the optical lens also includes an aperture stop STO, which is disposed in the optical path between the second lens 102 and the third lens 103. Adding an aperture stop STO to adjust the propagation direction of the light beam helps improve image quality. The aperture stop STO can be located in the optical path between the second lens 102 and the third lens 103, but the specific location of the aperture stop STO is not limited in this embodiment.

[0060] Optionally, a chip protection glass 10 is also provided along the object plane to the image plane; the chip protection glass 10 is located on the image-side side of the seventh lens 107. By providing a protective glass on the image-side side of the seventh lens 107, the photosensitive chip in the imaging sensor is protected. The imaging chip is used to convert the light signals collected by the optical lens into electrical signals, thereby ensuring the imaging effect of the optical lens.

[0061] The optical lens provided in this embodiment of the invention, through the rational allocation of the optical power, surface shape, refractive index, Abbe number, etc. of each lens, ensures the balance of the incident angle of the front and rear lens groups of the optical lens under the premise of low cost, reduces the sensitivity of the lens, ensures that the optical lens has high resolution, improves image quality, and meets the requirements of high-definition image quality; at the same time, it ensures the use requirements of the optical lens in high and low temperature environments, and achieves consistent image quality under different conditions. It achieves the technical effects of high pixel count, miniaturization, high definition, large aperture, weak ghosting, low temperature drift, and a total length of less than 22mm, greatly reducing costs.

[0062] Specific embodiments of the optical lens applicable to the above-described embodiments are further described below with reference to the accompanying drawings.

[0063] Example 1

[0064] Continue to refer to Figure 1An optical lens provided in Embodiment 1 of this utility model 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, and a seventh lens 107 arranged sequentially along the optical axis from the object plane to the image plane. The surface of the lens adjacent to the object plane is the object-side surface, and the surface of the lens adjacent to the image plane is the image-side surface. The object-side surface of the first lens 101 is convex, and the image-side surface is concave. The object-side surface of the second lens 102 is concave, and the image-side surface is convex. The object-side surface of the third lens 103 is convex, and the image-side surface is convex. The object-side surface of the fourth lens 104 is convex, and the image-side surface is flat. The object-side surface of the fifth lens 105 is convex, and the image-side surface is concave. The object-side surface of the sixth lens 106 is convex, and the image-side surface is convex. The central region of the object-side surface of the seventh lens 107 is convex, and the central region of the image-side surface is concave. As a possible implementation, Table 1 shows the range of curvature radius, thickness, refractive index, and Abbe number of each lens in the optical lens provided in the embodiment, wherein the units of curvature radius and thickness are millimeters (mm).

[0065] Table 1. One design value for an optical lens

[0066]

[0067] The surface number is assigned according to the order of the surfaces of each lens. For example, surface number "S1" represents the object side of the first lens 101, surface number "S2" represents the image side of the first lens 101, 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 surface with the center closer to the image surface, and a negative value means that the surface bends towards the image surface with the center closer to the object surface. "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. The material (nd) represents the refractive index, which is the ability of the material between the current surface and the next surface to deflect light. A space indicates that the current position is air and the refractive index is 1. The material (vd) represents the Abbe number, which is the dispersion characteristic of the material between the current surface and the next surface. A space indicates that the current position is air.

[0068] In Embodiment 1, the second lens 102 and the seventh lens 107 are aspherical lenses, and the aspherical surface shape equation Z of the first lens and the seventh lens satisfies:

[0069] ;

[0070] In the formula, Z is the distance sag from the vertex of the aspherical surface at a height of r along the optical axis; c = 1 / R, where R represents the paraxial radius of curvature of the mirror; K is the conic coefficient; A, B, C, D, and E are higher-order aspherical coefficients, where the units of Z, R, and r are all mm.

[0071] For example, Table 2 details the aspherical coefficients of each lens in this embodiment one of feasible implementations.

[0072] Table 2 Aspherical coefficients in optical lenses

[0073]

[0074] Where 1.84E-003 indicates that the coefficient A of face number 3 is 1.84 * 10. -3 And so on.

[0075] Figure 2 A ray fan pattern of an optical lens provided in Embodiment 1 of this utility model is shown below. Figure 2 As shown, the imaging range of different wavelengths of light (0.436μm, 0.486μm, 0.546μm, 0.587μm and 0.656μm) under different field of view angles of this optical lens is within 50μm and the curves are very concentrated, which ensures that the aberrations in different field of view areas are small, which means that the optical lens has well corrected the aberrations of the optical system.

[0076] Figure 3 An MTF diagram of an optical lens provided in Embodiment 1 of this utility model is shown below. Figure 3 As shown, the transfer function in the MTF curve at 160 line pairs / mm is generally above 0.4, which can meet the requirements of high-definition image quality.

[0077] Figure 4 An axial aberration curve of an optical lens is provided for Embodiment 1 of this utility model, as shown in the figure. Figure 4 As shown, 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). The phase difference of this optical lens at different wavelengths (0.436μm, 0.486μm, 0.546μm, 0.587μm, and 0.656μm) is within 0.05mm, and the curves for different wavelengths are relatively concentrated, indicating that the axial aberration of this optical lens is very small. Therefore, it can be seen that the optical lens provided by this embodiment can effectively correct aberrations.

[0078] Example 2

[0079] Figure 5This is a schematic diagram of the structure of an optical lens provided in Embodiment 2 of this utility model, as shown below. Figure 5 As shown, the optical lens provided in Embodiment 2 of this utility model includes a first lens 201, a second lens 202, a third lens 203, a fourth lens 204, a fifth lens 205, a sixth lens 206, and a seventh lens 207 arranged sequentially along the optical axis from the object plane to the image plane. The surface of the lens adjacent to the object plane is the object-side surface, and the surface of the lens adjacent to the image plane is the image-side surface. The object-side surface of the first lens 201 is convex, and the image-side surface is concave. The object-side surface of the second lens 202 is concave, and the image-side surface is convex. The object-side surface of the third lens 203 is convex, and the image-side surface is convex. The object-side surface of the fourth lens 204 is convex, and the image-side surface is concave. The object-side surface of the fifth lens 205 is convex, and the image-side surface is concave. The object-side surface of the sixth lens 206 is convex, and the image-side surface is convex. The central region of the object-side surface of the seventh lens 207 is convex, and the central region of the image-side surface is concave. The optical power, focal length, refractive index, Abbe number, surface shape, material of each lens, and the position of the optical lens stop STO are the same as in Example 1, and will not be repeated here.

[0080] As a possible implementation, Table 3 shows the range of curvature radius, thickness, refractive index, and Abbe number of each lens in the optical lens provided in the embodiment, wherein the units of curvature radius and thickness are millimeters (mm).

[0081] Table 3. One design value for optical lenses

[0082]

[0083] The surface number is assigned according to the order of the surfaces of each lens. For example, surface number "S1" represents the object side of the first lens 201, surface number "S2" represents the image side of the first lens 201, 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 surface with the center closer to the image surface, and a negative value means that the surface bends towards the image surface with the center closer to the object surface. "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. The material (nd) represents the refractive index, which is the ability of the material between the current surface and the next surface to deflect light. A space indicates that the current position is air and the refractive index is 1. The material (vd) represents the Abbe number, which is the dispersion characteristic of the material between the current surface and the next surface. A space indicates that the current position is air.

[0084] In Embodiment 2, the second lens 202 and the seventh lens 207 are aspherical lenses, and the aspherical surface shape equation Z of the first lens and the seventh lens satisfies:

[0085] ;

[0086] In the formula, Z is the distance sag from the vertex of the aspherical surface at a height of r along the optical axis; c = 1 / R, where R represents the paraxial radius of curvature of the mirror; K is the conic coefficient; A, B, C, D, and E are higher-order aspherical coefficients, where the units of Z, R, and r are all mm.

[0087] For example, Table 4 details the aspherical coefficients of each lens in this embodiment two according to a feasible implementation.

[0088] Table 4 Aspherical coefficient of optical lenses

[0089]

[0090] Where -9.254E-003 indicates that the coefficient A of face number 13 is 9.254 * 10. -3 And so on.

[0091] Figure 6 The light field pattern of an optical lens provided in Embodiment 2 of this utility model is as follows: Figure 6 As shown, the imaging range of different wavelengths of light (0.436μm, 0.486μm, 0.546μm, 0.587μm and 0.656μm) under different field of view angles of this optical lens is within 50μm and the curves are very concentrated, which ensures that the aberrations in different field of view areas are small, which means that the optical lens has well corrected the aberrations of the optical system.

[0092] Figure 7 An MTF diagram of an optical lens provided in Embodiment 2 of this utility model is shown below. Figure 7 As shown, the transfer function in the MTF curve at 160 line pairs / mm is generally above 0.4, which can meet the requirements of high-definition image quality.

[0093] Figure 8 An axial aberration curve of an optical lens is provided for Embodiment 2 of this utility model, as shown in the figure. Figure 8 As shown, 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). The phase difference of this optical lens at different wavelengths (0.436μm, 0.486μm, 0.546μm, 0.587μm, and 0.656μm) is within 0.05mm, and the curves for different wavelengths are relatively concentrated, indicating that the axial aberration of this optical lens is very small. Therefore, it can be seen that the optical lens provided by this embodiment can effectively correct aberrations.

[0094] Example 3

[0095] Figure 9 This is a schematic diagram of the structure of an optical lens provided in Embodiment 3 of this utility model, as shown below. Figure 9 As shown, the optical lens provided in Embodiment 3 of this utility model includes a first lens 301, a second lens 302, a third lens 303, a fourth lens 304, a fifth lens 305, a sixth lens 306, and a seventh lens 307 arranged sequentially along the optical axis from the object plane to the image plane. The surface of the lens adjacent to the object plane is the object-side surface, and the surface of the lens adjacent to the image plane is the image-side surface. The object-side surface of the first lens 301 is convex, and the image-side surface is concave. The object-side surface of the second lens 302 is concave, and the image-side surface is convex. The object-side surface of the third lens 303 is convex, and the image-side surface is convex. The object-side surface of the fourth lens 304 is convex, and the image-side surface is flat. The object-side surface of the fifth lens 305 is convex, and the image-side surface is concave. The object-side surface of the sixth lens 306 is convex, and the image-side surface is convex. The central region of the object-side surface of the seventh lens 307 is convex, and the central region of the image-side surface is concave. The optical power, focal length, refractive index, Abbe number, surface shape, material of each lens, and the position of the optical lens stop STO are the same as in Example 1, and will not be repeated here.

[0096] As a possible implementation, Table 5 shows the range of the radius of curvature, thickness, refractive index, and Abbe number of each lens in the optical lens provided in the embodiment, wherein the units of radius of curvature and thickness are millimeters (mm).

[0097] Table 5. One design value for optical lenses.

[0098]

[0099] The surface number is assigned according to the order of the surfaces of each lens. For example, surface number "S1" represents the object side of the first lens 301, surface number "S2" represents the image side of the first lens 301, and so on. "STO" represents the aperture stop STO 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 surface with the center closer to the image surface, and a negative value means that the surface bends towards the image surface with the center closer to the object surface. "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. The material (nd) represents the refractive index, that is, the ability of the material between the current surface and the next surface to deflect light. A space indicates that the current position is air and the refractive index is 1. The material (vd) represents the Abbe number, that is, the dispersion characteristic of the material between the current surface and the next surface to light. A space indicates that the current position is air.

[0100] In Embodiment 3, the second lens 302 and the seventh lens 307 are aspherical lenses, and the aspherical surface shape equation Z of the first lens and the seventh lens satisfies:

[0101] ;

[0102] In the formula, Z is the distance sag from the vertex of the aspherical surface at a height of r along the optical axis; c = 1 / R, where R represents the paraxial radius of curvature of the mirror; K is the conic coefficient; A, B, C, D, and E are higher-order aspherical coefficients, where the units of Z, R, and r are all mm.

[0103] For example, Table 6 details the aspherical coefficients of each lens in this embodiment three according to a feasible implementation.

[0104] Table 6 Aspherical coefficients in optical lenses

[0105]

[0106] Where 1.6669E-003 indicates that the coefficient A of face number 3 is 1.6669 * 10^33. -3 And so on.

[0107] Figure 10 The light field pattern of an optical lens provided in Embodiment 3 of this utility model is as follows: Figure 10 As shown, the imaging range of different wavelengths of light (0.436μm, 0.486μm, 0.546μm, 0.587μm and 0.656μm) under different field of view angles of this optical lens is within 50μm and the curves are very concentrated, which ensures that the aberrations in different field of view areas are small, which means that the optical lens has well corrected the aberrations of the optical system.

[0108] Figure 11 An MTF diagram of an optical lens provided in Embodiment 3 of this utility model is shown below. Figure 11 As shown, the transfer function in the MTF curve at 160 line pairs / mm is generally above 0.4, which can meet the requirements of high-definition image quality.

[0109] Figure 12 An axial aberration curve of an optical lens is provided for Embodiment 3 of this utility model, as shown in the figure. Figure 12 As shown, 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). The phase difference of this optical lens at different wavelengths (0.436μm, 0.486μm, 0.546μm, 0.587μm, and 0.656μm) is within 0.05mm, and the curves for different wavelengths are relatively concentrated, indicating that the axial aberration of this optical lens is very small. Therefore, it can be seen that the optical lens provided by this embodiment can effectively correct aberrations.

[0110] To provide a clearer explanation of the above embodiments, Table 7 details the specific optical physical parameters of each lens in the optical lens provided in embodiments one to three of this utility model, as well as other feasible optical physical parameters.

[0111] Table 7 Design values ​​of optical physical parameters of optical lenses

[0112]

[0113] 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, and a seventh lens arranged sequentially along the optical axis from the object plane to the image plane; 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 negative optical power, the sixth lens has positive optical power, and the seventh lens has positive optical power. The surface of the lens adjacent to the object plane is called the object-side surface, and the surface of the lens adjacent to the image plane is called the image-side surface; the object-side surface of the first lens is convex, and the image-side surface is concave; the object-side surface of the second lens is concave, and the image-side surface is convex; the object-side surface of the third lens is convex, and the image-side surface is convex; the object-side surface of the fourth lens is convex, and the image-side surface is either flat or concave; the object-side surface of the fifth lens is convex, and the image-side surface is concave; the object-side surface of the sixth lens is convex, and the image-side surface is convex; the central region of the object-side surface of the seventh lens is convex, and the central region of the image-side surface is concave. The object-side radius of curvature of the first lens is R1, the image-side radius of curvature of the fourth lens is R9, and the focal length of the optical lens is F, wherein: 4 < R1 / F < 6; R9 / F > 18.

2. The optical lens according to claim 1, characterized in that, 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, and the focal length of the seventh lens is f7, wherein: -2 <f1 / F<0; -30<f2 / F<0; 1.8<f3 / F<3; 2<f4 / F<5; -2<f5 / F<0; 0<f6 / F<2; 0<f7 / F<60。 3. The optical lens according to claim 1, characterized in that, The fifth lens and the sixth lens are cemented together to form a cemented lens group, the focal length of the cemented lens group is f56, and the focal length of the optical lens is F, wherein: 10≤|f56 / F|≤80.

4. The optical lens according to claim 1, characterized in that, The first lens has a refractive index of nd1 and an Abbe number of vd1; the second lens has a refractive index of nd2 and an Abbe number of vd2; the third lens has a refractive index of nd3 and an Abbe number of vd3; the fourth lens has a refractive index of nd4 and an Abbe number of vd4; the fifth lens has a refractive index of nd5 and an Abbe number of vd5; the sixth lens has a refractive index of nd6 and an Abbe number of vd6; and the seventh lens has a refractive index of nd7 and an Abbe number of vd7; wherein: 1.75≤nd1≤1.92; 30.0≤vd1≤55.0; 1.47≤nd2≤1.65; 43.3≤vd2≤68.0; 1.83≤nd3≤1.96; 24.3≤vd3≤35.8; 1.43≤nd4≤1.73; 48.0≤vd4≤72.6; 1.85≤nd5≤2.05; 15.3≤vd5≤35.6; 1.52≤nd6≤1.71; 53.2≤vd6≤68.0; 1.45≤nd7≤1.80; 20.0≤vd7≤68.

0.

5. The optical lens according to claim 1, characterized in that, The optical aperture of the object side of the first lens is D, and the image height corresponding to the maximum field of view of the optical lens is ImgH, where: 1.2≤D / ImgH≤1.

8.

6. The optical lens according to claim 1, characterized in that, The total optical length of the optical lens is TTL, and the optical back focal length of the optical lens is BFL, wherein BFL / TTL≥0.

1.

7. The optical lens according to claim 1, characterized in that, The total optical length of the optical lens is TTL, and the entrance pupil diameter of the optical lens is ENPD, wherein: ENPD / TTL > 0.

3.

8. The optical lens according to claim 1, characterized in that, The optical power of the second lens is φ2, and the optical power of the seventh lens is φ7, wherein -5 < φ2 / φ7 < -1.

9. The optical lens according to claim 1, characterized in that, The first lens, the third lens, the fourth lens, the fifth lens, and the sixth lens are all glass spherical lenses; the second lens and the seventh lens are both plastic aspherical lenses.

10. The optical lens according to claim 1, characterized in that, The optical lens also includes an aperture stop, which is disposed in the optical path between the second lens and the third lens.

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