Optical lens

Abstract

The utility model discloses an optical lens comprising a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens and a seventh lens which are sequentially arranged from an object plane to an image plane along an optical axis. The first lens, the second lens and the sixth lens are all negative focal power lenses, and the third lens, the fourth lens, the fifth lens and the seventh lens are all positive focal power lenses; the focal power of the first lens is phi 1, the focal power of the second lens is phi 2, the focal power of the third lens is phi 3, the focal power of the fourth lens is phi 4, the focal power of the seventh lens is phi 7, and the focal power of the optical lens is phi, wherein-0.79 lt; phi 1 / phi lt; -0.52,-0.52; -0.13 lt,-0.13 lt; phi < 2 > / phi < lt >; -0.05, and-0.05; 0.22 lt; 0.22 lt; phi 3 / phi lt; 0.35 part; 0.2 lt; phi 4 / phi lt; 0.34, 0.34; 0.15 lt; phi 7 / phi lt; and 0.41. The optical lens provided by the utility model improves the imaging quality, and meets the use requirements of small size, large field angle and large target surface.

Description

Technical Field

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

[0002] With the development of automobiles, there is an increasing emphasis on the development of assisted driving features. In-vehicle DVR lenses can provide visual information for assisted driving systems, helping vehicles identify road signs, traffic signals, pedestrians, vehicles, and other objects, thereby improving driving safety and comfort. As a core component of assisted driving systems, the performance of optical lenses directly impacts the system's monitoring effectiveness and reliability. Currently, existing automotive optical lenses on the market suffer from complex structures, unstable performance, limited field of view, and poor chip compatibility. Utility Model Content

[0003] The utility model provides an optical lens to achieve the use requirements of small size, large field angle and large target surface.

[0004] According to one aspect of the present invention, an optical lens is provided, comprising a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens arranged in sequence along an optical axis from an object plane to an image plane;

[0005] The first lens, the second lens, and the sixth lens are all negative power lenses, and the third lens, the fourth lens, the fifth lens, and the seventh lens are all positive power lenses;

[0006] The focal power of the first lens is Φ1, the focal power of the second lens is Φ2, the focal power of the third lens is Φ3, the focal power of the fourth lens is Φ4, the focal power of the seventh lens is Φ7, and the focal power of the optical lens is Φ, wherein:

[0007] -0.79<Φ1 / Φ<-0.52; -0.13<Φ2 / Φ<-0.05; 0.22<Φ3 / Φ<0.35; 0.2<Φ4 / Φ<0.34; 0.15<Φ7 / Φ<0.41.

[0008] Optionally, the fifth lens and the sixth lens form a cemented lens group; the focal power of the cemented lens group is Φ56, and the focal power of the optical lens is Φ, wherein:

[0009] -0.03<Φ56 / Φ<0.03.

[0010] Optionally, the surface of the lens adjacent to the object plane is the object surface, and the surface of the lens adjacent to the image plane is the image surface; the object surface of the first lens is convex toward the object plane, and the image surface of the first lens is convex toward the object plane; the object surface of the second lens is convex toward the image plane, and the image surface of the second lens is convex toward the image plane; the object surface of the third lens is convex toward the object plane, and the image surface of the third lens is convex toward the object plane; the object surface of the fourth lens is convex toward the object plane; the object surface of the fifth lens is convex toward the object plane, and the image surface of the fifth lens is convex toward the image plane; the object surface of the sixth lens is convex toward the image plane, and the image surface of the sixth lens is convex toward the object plane; the object surface of the seventh lens is convex toward the object plane, and the image surface of the seventh lens is convex toward the image plane.

[0011] Optionally, the first lens, the second lens, the third lens and the fourth lens are all glass spherical lenses, and the fifth lens, the sixth lens and the seventh lens are all plastic aspherical lenses.

[0012] Optionally, the refractive index of the second lens is Nd2; the refractive index of the third lens is Nd3;

[0013] in:

[0014] 1.7 <Nd2<2;1.7<Nd3<2。

[0015] Optionally, the distance from the optical axis center of the image-side surface of the seventh lens to the image plane is BFL, and the distance from the optical axis center of the object-side surface of the first lens to the image plane is TTL; wherein:

[0016] 0.1 <BFL / TTL<0.2。

[0017] Optionally, the distance from the optical axis center of the object-side surface of the first lens to the image plane is TTL, and the total image height of the optical lens is ImgH, wherein:

[0018] 2.7 <TTL / ImgH<2.95。

[0019] Optionally, the aperture number of the optical lens is F, where:

[0020] F≥1.8.

[0021] Optionally, the field of view of the optical lens is FOV, where:

[0022] FOV ≥ 140°.

[0023] Optionally, the optical lens further includes a diaphragm;

[0024] The aperture is located in the optical path between the third lens and the fourth lens.

[0025] The technical solution of the embodiment of the utility model is that the optical lens includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens and a seventh lens arranged in sequence along the optical axis from the object plane to the image plane, the first lens, the second lens and the sixth lens are all negative optical power lenses, and the third lens, the fourth lens, the fifth lens and the seventh lens are all positive optical power lenses; the optical power of the first lens is Φ1, the optical power of the second lens is Φ2, the optical power of the third lens is Φ3, the optical power of the fourth lens is Φ4, the optical power of the seventh lens is Φ7, and the optical power of the optical lens is Φ, wherein: -0.79<Φ1 / Φ<-0.52; -0.13<Φ2 / Φ<-0.05; 0.22<Φ3 / Φ<0.35; 0.2<Φ4 / Φ<0.34; 0.15<Φ7 / Φ<0.41. By reasonably setting the optical power of each lens and the optical lens, the optical lens can be guaranteed to meet the requirements of small size, large field of view and large target surface while being small in volume and low in cost.

[0026] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present invention, nor is it intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0028] Figure 1 A schematic structural diagram of an optical lens provided in Example 1 of the present utility model;

[0029] Figure 2 This is an axial aberration curve diagram of an optical lens provided in Example 1 of the present utility model;

[0030] Figure 3 A schematic structural diagram of an optical lens provided in Example 2 of the present utility model;

[0031] Figure 4 This is an axial aberration curve diagram of an optical lens provided in Example 2 of the present utility model;

[0032] Figure 5This is a schematic structural diagram of an optical lens provided in Example 3 of the present utility model;

[0033] Figure 6 This is an axial aberration curve diagram of an optical lens provided in Example 3 of the present utility model. DETAILED DESCRIPTION

[0034] In order to help those skilled in the art better understand the present invention, the following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0035] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0036] Example 1

[0037] Figure 1 This is a schematic diagram of the structure of an optical lens provided in Example 1 of the present invention. The optical lens 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, which are arranged in sequence from the object plane to the image plane along the optical axis; the first lens 101, the second lens 102, and the sixth lens 106 are all negative focal length lenses, and the third lens 103, the fourth lens 104, the fifth lens 105, and the seventh lens 107 are all positive focal length lenses. The focal power of the first lens 101 is Φ1, the focal power of the second lens 102 is Φ2, the focal power of the third lens 103 is Φ3, the focal power of the fourth lens 104 is Φ4, the focal power of the seventh lens 107 is Φ7, and the focal power of the optical lens is Φ, wherein: -0.79<Φ1 / Φ<-0.52; -0.13<Φ2 / Φ<-0.05; 0.22<Φ3 / Φ<0.35; 0.2<Φ4 / Φ<0.34; 0.15<Φ7 / Φ<0.41.

[0038] Among them, the optical power is equal to the difference between the convergence of the image-side beam and the convergence of the object-side beam, which characterizes the ability of the optical system to deflect light. The larger the absolute value of the optical power, the stronger the ability to bend light, and the smaller the absolute value of the optical power, the weaker the ability to bend light. When the optical power is a positive number, the refraction of light is convergent; when the optical power is a negative number, the refraction of light is divergent. The optical power can be used to characterize a certain refractive surface of a lens (i.e., a surface of a lens), can be used to characterize a certain lens, and can also be used to characterize a system formed by multiple lenses (i.e., a lens group).

[0039] In the optical lens provided in this embodiment, each lens can be fixed to a lens barrel ( Figure 1 In the optical lens (not shown), the first lens 101 has a negative optical focal power, the second lens 102 has a negative optical focal power, the third lens 103 has a positive optical focal power, the fourth lens 104 has a positive optical focal power, the fifth lens 105 has a positive optical focal power, the sixth lens 106 has a negative optical focal power, and the seventh lens 107 has a positive optical focal power, so that the optical focal power of the entire optical lens is distributed according to a certain proportion, ensuring the balance of the incident angles of the front and rear lens groups, thereby reducing the sensitivity of the lens and improving the possibility of production.

[0040] The focal power of the first lens 101 satisfies the following requirements: -0.79 < Φ1 / Φ < -0.52. Within this range, the focal power of the first lens 101 smoothly channels object-side light into the imaging system while reducing the lens front aperture. The focal power of the second lens 102 satisfies the following requirements: -0.13 < Φ2 / Φ < -0.05. The focal power of the third lens 103 satisfies the following requirements: 0.22 < Φ3 / Φ < 0.35. Adjusting the focal power of the second and third lenses 102 and 103 increases light convergence, improving overall image brightness and contrast. The focal power of the fourth lens 104 satisfies the following requirements: 0.2 < Φ4 / Φ < 0.34. The fourth lens 104 is a glass lens with a high Abbe number, effectively reducing chromatic aberration in the system and achieving high-definition image quality. The focal power of the seventh lens 107 satisfies the following requirements: 0.15 < Φ7 / Φ < 0.41. The optical power of the seventh lens 107 is conducive to achieving a large target surface, and can effectively reduce the light emission angle of the system, thereby facilitating better matching with the imaging sensor.

[0041] Optionally, the fifth lens 105 and the sixth lens 106 form a cemented lens group; the focal length of the cemented lens group is Φ56, and the focal length of the optical lens is Φ, wherein: -0.03<Φ56 / Φ<0.03.

[0042] The fifth lens 105 and the sixth lens 106 are combined into a cemented lens. The cemented lens effectively reduces the air gap between the fifth and sixth lenses 105, 106, thereby shortening the overall lens length. The fifth lens 105 is a positive, high-Abbe-number plastic lens, while the sixth lens 106 is a negative, low-Abbe-number plastic lens. By cementing these plastic lenses with different dispersion characteristics together, they effectively correct aberrations caused by differences in the refractive indices of different colors, thereby improving color reproduction and image clarity. Furthermore, the cemented lens can be used to minimize or eliminate chromatic aberration, fully correcting various aberrations in the optical lens. This improves resolution and optimizes optical properties such as distortion and CRA while maintaining a compact design. It also reduces light loss caused by inter-lens reflections, increasing illumination, thereby improving image quality and enhancing image clarity. Furthermore, the use of a cemented lens reduces the number of components between the two lenses, simplifying the assembly process during lens manufacturing, reducing costs, and reducing sensitivity to tolerances such as tilt and deflection that can occur during the lens unit assembly process.

[0043] Optionally, the surface of the lens adjacent to the object plane is the object surface, and the surface of the lens adjacent to the image plane is the image surface; the object surface of the first lens 101 is convex toward the object plane, and the image surface of the first lens 101 is convex toward the object plane; the object surface of the second lens 102 is convex toward the image plane, and the image surface of the second lens 102 is convex toward the image plane; the object surface of the third lens 103 is convex toward the object plane, and the image surface of the third lens 103 is convex toward the object plane; the object surface of the fourth lens 104 is convex toward the object plane; the object surface of the fifth lens 105 is convex toward the object plane, and the image surface of the fifth lens 105 is convex toward the image plane; the object surface of the sixth lens 106 is convex toward the image plane, and the image surface of the sixth lens 106 is convex toward the object plane; the object surface of the seventh lens 107 is convex toward the object plane, and the image surface of the seventh lens 107 is convex toward the image plane.

[0044] For example, Figure 1As shown, the image-side surface of the first lens 101 is convex toward the object plane; the object-side surface of the second lens 102 is convex toward the image plane. The first lens 101 is a meniscus lens, which is used to control the incident angle of the optical system, so that the object-side light can be smoothly input into the imaging system while reducing the front diameter of the lens. The image-side surface of the second lens 102 is convex toward the image plane; the object-side surface of the third lens 103 is convex toward the object plane, and the image-side surface of the third lens 103 is convex toward the object plane; the object-side surface of the fourth lens 104 is convex toward the object plane, and the image-side surface of the fourth lens 104 is flat; the object-side surface of the fifth lens 105 is convex toward the object plane, and the image-side surface of the fifth lens 105 is convex toward the image plane; the object-side surface of the sixth lens 106 is convex toward the image plane, and the image-side surface of the sixth lens 106 is convex toward the object plane; the object-side surface of the seventh lens 107 is convex toward the object plane, and the image-side surface of the seventh lens 107 is convex toward the object plane. The seventh lens 107 is a biconvex positive lens. The optical focal length of the seventh lens 107 within this range is conducive to the realization of a large target surface, and can effectively reduce the light emission angle of the system, thereby facilitating better matching with the imaging sensor.

[0045] By reasonably setting the surface shape of each lens, the optical power and focal length of each lens can be ensured to meet the optical power and focal length requirements of the above embodiment, while also ensuring that the entire optical lens structure is compact and the optical lens has a high degree of integration.

[0046] Optionally, the first lens 101 , the second lens 102 , the third lens 103 and the fourth lens 104 are all glass spherical lenses, and the fifth lens 105 , the sixth lens 106 and the seventh lens 107 are all plastic aspherical lenses.

[0047] Among them, the first lens 101, the second lens 102, the third lens 103, and the fourth lens 04 are all glass spherical lenses. The portion of the lens near the object plane is configured as a glass spherical lens to improve the lens's impact resistance, ensure structural stability and adaptability to in-vehicle applications. The fifth lens 105, the sixth lens 106, and the seventh lens 107 are all plastic aspherical lenses. Aspherical lenses correct for aberrations such as field curvature, astigmatism, spherical aberration, and coma. The material of the plastic aspherical lens can be various plastics known to those skilled in the art, and the material of the glass spherical lens can be various types of glass known to those skilled in the art. This embodiment of the utility model does not elaborate on or limit this. Because the cost of plastic lenses is much lower than that of glass lenses, the optical lens provided in the embodiment of the utility model, by providing three plastic aspherical lenses, achieves high image quality and low cost. Furthermore, because the two types of materials complement each other, the black light lens can be used normally in high and low temperature environments.

[0048] Optionally, the refractive index of the second lens 102 is Nd2; the refractive index of the third lens 103 is Nd3; where: 1.7 < Nd2 < 2; 1.7 < Nd3 < 2.

[0049] The refractive index is the ratio of the speed of light in a vacuum to the speed of light in the medium, mainly used to describe the refraction ability of the material to light. Different materials have different refractive indices. The second and third lenses use high refractive index glass spherical lenses, which can bend light more strongly, thereby increasing the light converging ability, improving the overall brightness and contrast of the image. At the same time, under the same optical performance requirements, the lenses with high refractive indices are thinner, which helps to reduce the overall axial length of the lens.

[0050] In this embodiment, by setting the refractive indices of the lenses in the optical lens in a coordinated manner, it is beneficial to achieve the miniaturized design of the optical lens. At the same time, it can also ensure the balance of the incident angle sizes of the front and rear lens groups, so as to reduce the sensitivity of the lens and improve the manufacturability. <(

[0051] Optionally, the distance from the optical axis center of the image side surface of the seventh lens 107 to the image plane is BFL, and the distance from the optical axis center of the object side surface of the first lens 101 to the image plane is TTL; where: 0.1 < BFL / TTL < 0.2.

[0052] Exemplarily, the distance from the optical axis center of the image side surface of the seventh lens 107 to the image plane can be understood as the back focal length of the optical lens. By reasonably setting the relationship between the back focal length of the optical lens and the total length of the optical lens, it can be ensured that the entire optical lens structure is compact and the integration of the optical lens is high.

[0053] Optionally, the distance from the optical axis center of the object side surface of the first lens 101 to the image plane is TTL, and the full image height of the optical lens is ImgH, where: 2.7 < TTL / ImgH < 2.95. By controlling the ratio of the total length of the optical lens to the full image height of the optical lens, it is beneficial to control the total length of the optical lens, and thus beneficial to achieve the miniaturized design of the optical lens.

[0054] Optionally, the aperture number of the optical lens is F, where: F ≥ 1.8. The function of the aperture is to determine the amount of light entering the optical lens and adjust the amount of light entering the optical lens. The smaller the aperture number, the larger the aperture and the more the amount of light entering; conversely, the larger the aperture number, the smaller the aperture and the less the amount of light entering. The optical lens provided in the embodiment of the present invention is a large aperture lens, which meets the ultra-large throughput and is suitable for use requirements under low illumination conditions to ensure the clarity of the image.

[0055] Optionally, the field of view of the optical lens is FOV, where FOV≥140°. The optical lens provided by the embodiment of the utility model has a wide field of view, which reduces visual blind spots and improves driving safety.

[0056] Optionally, the optical lens further includes a stop STO; the stop STO is located in the optical path between the third lens 103 and the fourth lens 104 .

[0057] Among them, by arranging the aperture STO in the optical path between the third lens 103 and the fourth lens 104, the propagation direction of the light beam can be adjusted, and the incident angle of the light can be adjusted, which is beneficial to improving the imaging quality.

[0058] The optical lens further includes a filter 10 disposed along the object plane to the image plane; the filter 10 is located on the image-side surface of the seventh lens element 107. The filter 10 can filter out unwanted stray light, thereby improving the image quality of the optical lens. For example, the filter 10 can filter out infrared light during the day, thereby improving the imaging quality of the optical lens.

[0059] The optical lens also includes a chip protection glass, located along the image plane from the object plane to the image plane. This glass is located on the image-side surface of the filter. This protects the photosensitive chip in the imaging sensor, which converts the light signals collected by the optical lens into electrical signals, thereby ensuring the imaging effect of the optical lens.

[0060] The embodiment of the utility model uses an optical lens arrangement of a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens and a filter arranged in sequence along the optical axis from the object plane to the image plane. A mixed combination of four spherical glass lenses and three aspherical plastic lenses is adopted, which can well correct aberrations and ensure sufficiently good image quality. It can simultaneously meet the requirements of a large target surface and a large field of view. The total length of the lens is less than 24.5mm, and it can be used with an 8MP, 1 / 1.8-inch chip. The FOV can reach 140°, achieving excellent imaging, compact structure, a large field of view and a large aperture, and is suitable for vehicle-mounted application environments.

[0061] As a feasible implementation manner, the curvature radius, thickness, refractive index, Abbe number and k value of each lens surface in the optical lens are exemplarily described below.

[0062] Table 1 shows the ranges of the curvature radius, thickness, refractive index, Abbe number and k value of each lens in the optical lens provided in Example 1, wherein the units of the curvature radius and thickness are both millimeters (mm).

[0063] Table 1 A design value of optical lens

[0064]

[0065] Among them, the surface numbers are numbered according to the order of the surfaces of each lens, where "S1" represents the object-side surface of the first lens 101, "S2" represents the image-side surface of the first lens 101, "S4" represents the object-side surface of the second lens 102, and "S5" represents the image-side surface of the second lens 102; the radius of curvature represents the degree of curvature of the lens surface, a positive value represents that the surface is bent toward the image side, and a negative value represents that the surface is bent toward the object side; the thickness represents the central axial distance from the current surface to the next surface, where "Infinity" represents that the surface is a plane and the radius of curvature is infinite; the thickness represents the central axial distance from the current surface to the next surface, the refractive index represents the ability of the material between the current surface and the next surface to deflect light, and a blank space represents that the current position is air with a refractive index of 1; the Abbe number represents the dispersion characteristics of the material between the current surface and the next surface to light, and a blank space represents that the current position is air.

[0066] The aspheric cone coefficient can be defined by the following aspheric formula, but is not limited to the following expression method:

[0067]

[0068] Where Z is the distance vector height of the aspheric surface from the vertex of the aspheric surface at a height of y along the optical axis; r is the height of the aspheric surface; c is the curvature of the fitted sphere, which is the inverse of the curvature radius; k is the fitted cone coefficient; A, B, C, D, and E are the coefficients of the 4th, 6th, 8th, 10th, and 12th order terms of the aspheric polynomial, respectively.

[0069] For example, Table 2 describes in detail the aspheric coefficients of each lens in the first embodiment in a feasible implementation manner.

[0070] Table 2 Aspheric coefficients of each lens in the optical lens

[0071]

[0072] Among them, 1.424328E-03 means that the coefficient A of the surface number S10 is 1.424328*10 -3 , and so on.

[0073] The optical lens of the first embodiment achieves the following technical indicators:

[0074] Focal length: f = 4.00 mm;

[0075] Aperture: F=1.8.

[0076] Further, Figure 2 This is an axial aberration curve diagram of an optical lens provided in Example 1 of the present utility model, such as Figure 2As shown in the figure, the vertical direction represents the normalized aperture, 0 represents the optical axis, and the vertical vertex represents the maximum pupil radius; the horizontal direction represents the offset relative to the ideal focus, in millimeters (mm). The different linear curves in the figure represent different wavelengths of system imaging. The spherical aberration of the optical lens at different wavelengths (0.436μm, 0.486μm, 0.546μm, 0.587μm and 0.656μm) is within 0.1mm. The curves at different wavelengths are relatively concentrated, indicating that the axial aberration of the optical lens is very small. Therefore, it can be seen that the optical lens provided in Example 1 of the present invention can well correct aberrations.

[0077] Example 2

[0078] Figure 3 This is a schematic structural diagram of an optical lens provided in Example 2 of the present utility model. The optical lens 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, which are arranged in sequence along the optical axis from the object plane to the image plane; the first lens 201, the second lens 202 and the sixth lens 206 are all negative optical power lenses, and the third lens 203, the fourth lens 204, the fifth lens 205 and the seventh lens 207 are all positive optical power lenses; the aperture STO is located in the optical path between the third lens 203 and the fourth lens 204.

[0079] The object-side surface of the first lens 201 is convex toward the object plane, and the image-side surface of the first lens 202 is convex toward the object plane; the object-side surface of the second lens 202 is convex toward the image plane, and the image-side surface of the second lens 202 is convex toward the image plane; the object-side surface of the third lens 203 is convex toward the object plane, and the image-side surface of the third lens 203 is convex toward the object plane; the object-side surface of the fourth lens 204 is convex toward the object plane, and the image-side surface of the fourth lens 204 is convex toward the image plane; the object-side surface of the fifth lens 205 is convex toward the object plane, and the image-side surface of the fifth lens 205 is convex toward the image plane; the object-side surface of the sixth lens 206 is convex toward the image plane, and the image-side surface of the sixth lens 206 is convex toward the object plane; the object-side surface of the seventh lens 207 is convex toward the object plane, and the image-side surface of the seventh lens 207 is convex toward the image plane.

[0080] Table 3 shows the ranges of the curvature radius, thickness, refractive index, Abbe number and k value of each lens in the optical lens provided in Example 2, wherein the units of the curvature radius and thickness are both millimeters (mm).

[0081] Table 3 A design value of optical lens

[0082]

[0083]

[0084] Among them, the surface numbers are numbered according to the order of the surfaces of each lens, where "S1" represents the object surface of the first lens 201, "S2" represents the image surface of the first lens 201, "S4" represents the object surface of the second lens 202, and "S5" represents the image surface of the second lens 202; the radius of curvature represents the degree of curvature of the lens surface, a positive value represents that the surface is bent toward the image side, and a negative value represents that the surface is bent toward the object side; the thickness represents the central axial distance from the current surface to the next surface, where "Infinity" represents that the surface is a plane and the radius of curvature is infinite; the thickness represents the central axial distance from the current surface to the next surface, the refractive index represents the ability of the material between the current surface and the next surface to deflect light, and a blank space represents that the current position is air and the refractive index is 1; the Abbe number represents the dispersion characteristics of the material between the current surface and the next surface to light, and a blank space represents that the current position is air.

[0085] The aspheric cone coefficient can be defined by the following aspheric formula, but is not limited to the following expression method:

[0086]

[0087] Where Z is the distance vector height of the aspheric surface from the vertex of the aspheric surface at a height of y along the optical axis; r is the height of the aspheric surface; c is the curvature of the fitted sphere, which is the inverse of the curvature radius; k is the fitted cone coefficient; A, B, C, D, and E are the coefficients of the 4th, 6th, 8th, 10th, and 12th order terms of the aspheric polynomial, respectively.

[0088] For example, Table 4 details the aspheric coefficients of each lens in the second embodiment in a feasible implementation manner.

[0089] Table 4 Aspheric coefficients of each lens in the optical lens

[0090]

[0091]

[0092] Among them, 1.010531E-03 means that the coefficient A of the surface number S10 is 1.010531*10 -3 , and so on.

[0093] The optical lens of the second embodiment achieves the following technical indicators:

[0094] Focal length: f=4.12mm;

[0095] Aperture: F=1.8.

[0096] Further, Figure 4This is an axial aberration curve diagram of an optical lens provided in Example 2 of the present utility model, as shown in FIG. Figure 4 As shown, the vertical direction represents the normalized aperture, 0 represents the optical axis, and the vertical vertex represents the maximum pupil radius; the horizontal direction represents the offset relative to the ideal focus, in millimeters (mm). The different linear curves in the figure represent different wavelengths of system imaging. The spherical aberration of the optical lens at different wavelengths (0.436μm, 0.486μm, 0.546μm, 0.587μm and 0.656μm) is within 0.1mm. The curves at different wavelengths are relatively concentrated, indicating that the axial aberration of the optical lens is very small. Therefore, it can be seen that the optical lens provided in Example 2 of the present invention can well correct aberrations.

[0097] Example 3

[0098] Figure 5 This is a structural schematic diagram of an optical lens provided in Example 3 of the present invention. The optical lens 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, which are arranged in sequence along the optical axis from the object plane to the image plane; the first lens 301, the second lens 302 and the sixth lens 306 are all negative optical focal length lenses, and the third lens 303, the fourth lens 304, the fifth lens 305 and the seventh lens 307 are all positive optical focal length lenses; the aperture STO is located in the optical path between the third lens 303 and the fourth lens 303.

[0099] The object-side surface of the first lens 301 is convex toward the object plane, and the image-side surface of the first lens 301 is convex toward the object plane; the object-side surface of the second lens 302 is convex toward the image plane, and the image-side surface of the second lens 302 is convex toward the image plane; the object-side surface of the third lens 303 is convex toward the object plane, and the image-side surface of the third lens 303 is convex toward the object plane; the object-side surface of the fourth lens 304 is convex toward the object plane, and the image-side surface of the fourth lens 304 is convex toward the object plane; the object-side surface of the fifth lens 305 is convex toward the object plane, and the image-side surface of the fifth lens 305 is convex toward the image plane; the object-side surface of the sixth lens 306 is convex toward the image plane, and the image-side surface of the sixth lens 306 is convex toward the object plane; the object-side surface of the seventh lens 307 is convex toward the object plane, and the image-side surface of the seventh lens 307 is convex toward the image plane.

[0100] Table 5 shows the ranges of the curvature radius, thickness, refractive index, Abbe number and k value of each lens in the optical lens provided in Example 3, where the units of the curvature radius and thickness are both millimeters (mm).

[0101] Table 5 A design value of optical lens

[0102]

[0103] Among them, the surface numbers are numbered according to the order of the surfaces of each lens, where "S1" represents the object-side surface of the first lens 301, "S2" represents the image-side surface of the first lens 301, "S4" represents the object-side surface of the second lens 302, and "S5" represents the image-side surface of the second lens 302; the radius of curvature represents the degree of curvature of the lens surface, a positive value represents that the surface is bent toward the image side, and a negative value represents that the surface is bent toward the object side; the thickness represents the central axial distance from the current surface to the next surface, where "Infinity" represents that the surface is a plane and the radius of curvature is infinite; the thickness represents the central axial distance from the current surface to the next surface, the refractive index represents the ability of the material between the current surface and the next surface to deflect light, and a blank space represents that the current position is air and the refractive index is 1; the Abbe number represents the dispersion characteristics of the material between the current surface and the next surface to light, and a blank space represents that the current position is air.

[0104] The aspheric cone coefficient can be defined by the following aspheric formula, but is not limited to the following expression method:

[0105]

[0106] Where Z is the distance vector height of the aspheric surface from the vertex of the aspheric surface at a height of y along the optical axis; r is the height of the aspheric surface; c is the curvature of the fitted sphere, which is the inverse of the curvature radius; k is the fitted cone coefficient; A, B, C, D, and E are the coefficients of the 4th, 6th, 8th, 10th, and 12th order terms of the aspheric polynomial, respectively.

[0107] For example, Table 6 details the aspheric coefficients of each lens in Example 3 in a feasible implementation manner.

[0108] Table 6 Aspheric coefficients of each lens in the optical lens

[0109]

[0110] Among them, 1.424328E-03 means that the coefficient A of the surface number S10 is 1.424328*10 -3 , and so on.

[0111] The optical lens of the third embodiment achieves the following technical indicators:

[0112] Focal length: f=3.97mm;

[0113] Aperture: F=1.8.

[0114] Further, Figure 6 This is an axial aberration curve diagram of an optical lens provided in Example 3 of the present utility model, as shown in FIG. Figure 6As shown, the vertical direction represents the normalized aperture, 0 represents the optical axis, and the vertical vertex represents the maximum pupil radius; the horizontal direction represents the offset relative to the ideal focus, in millimeters (mm). The different linear curves in the figure represent different wavelengths of system imaging. The spherical aberration of the optical lens at different wavelengths (0.436μm, 0.486μm, 0.546μm, 0.587μm and 0.656μm) is within 0.1mm. The curves at different wavelengths are relatively concentrated, indicating that the axial aberration of the optical lens is very small. Therefore, it can be seen that the optical lens provided in Example 3 of the present invention can well correct aberrations.

[0115] In order to more clearly illustrate the above embodiments, Table 7 details the specific optical and physical parameters of each lens in the optical lens provided in Embodiments 1 to 3 of the present invention, as well as other feasible optical and physical parameters.

[0116] Table 7 Design values ​​of optical physical parameters of optical lens

[0117]

[0118] The above specific embodiments do not limit the scope of protection of this utility model. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model shall be included within the scope of protection of this utility model.

Claims

1. An optical lens, characterized in that: comprising a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens and a seventh lens arranged in sequence along the optical axis from the object plane to the image plane; The first lens, the second lens, and the sixth lens are all negative power lenses, and the third lens, the fourth lens, the fifth lens, and the seventh lens are all positive power lenses; The focal power of the first lens is Φ1, the focal power of the second lens is Φ2, the focal power of the third lens is Φ3, the focal power of the fourth lens is Φ4, the focal power of the seventh lens is Φ7, and the focal power of the optical lens is Φ, wherein: -0.79<Φ1 / Φ<-0.52; -0.13<Φ2 / Φ<-0.05; 0.22<Φ3 / Φ<0.35; 0.2<Φ4 / Φ<0.34; 0.15<Φ7 / Φ<0.

41.

2. The optical lens according to claim 1, wherein: The fifth lens and the sixth lens form a cemented lens group; the focal length of the cemented lens group is Φ56, and the focal length of the optical lens is Φ, wherein: -0.03<Φ56 / Φ<0.

03.

3. The optical lens according to claim 1, wherein: 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 is convex toward the object plane, and the image-side surface of the first lens is convex toward the object plane; The object-side surface of the second lens is convex toward the image plane, and the image-side surface of the second lens is convex toward the image plane; The object-side surface of the third lens is convex toward the object plane, and the image-side surface of the third lens is convex toward the object plane; The object-side surface of the fourth lens is convex toward the object plane; the object-side surface of the fifth lens is convex toward the object plane, and the image-side surface of the fifth lens is convex toward the image plane; The object-side surface of the sixth lens is convex toward the image plane, and the image-side surface of the sixth lens is convex toward the object plane; An object-side surface of the seventh lens is convex toward the object plane, and an image-side surface of the seventh lens is convex toward the image plane.

4. The optical lens according to claim 1, wherein: The first lens, the second lens, the third lens, and the fourth lens are all glass spherical lenses, and the fifth lens, the sixth lens, and the seventh lens are all plastic aspherical lenses.

5. The optical lens according to claim 1, wherein: The refractive index of the second lens is Nd2; the refractive index of the third lens is Nd3; wherein: 1.7 <Nd2<2;1.7<Nd3<2。 6. The optical lens according to claim 1, wherein: The distance from the optical axis center of the image-side surface of the seventh lens to the image plane is BFL, and the distance from the optical axis center of the object-side surface of the first lens to the image plane is TTL; wherein: 0.1 <BFL / TTL<0.2。 7. The optical lens according to claim 1, wherein: The distance from the optical axis center of the object-side surface of the first lens to the image plane is TTL, and the total image height of the optical lens is ImgH, wherein: 2.7 <TTL / ImgH<2.95。 8. The optical lens according to claim 1, wherein: The aperture number of the optical lens is F, where: F≥1.8。 9. The optical lens according to claim 1, wherein: The field of view of the optical lens is FOV, where: FOV ≥ 140°.

10. The optical lens according to claim 1, wherein: The optical lens further includes a diaphragm; The aperture is located in the optical path between the third lens and the fourth lens.

Images