Low-distortion aspheric optical lens

Abstract

The utility model relates to a kind of low-distortion aspheric surface optical lens, including first lens, second lens, third lens, fourth lens, fifth lens, sixth lens, seventh lens, eighth lens, ninth lens and tenth lens in order from object side to image side along an optical axis;The object side of fourth lens is set as seventh surface, the image side of fourth lens is set as eighth surface, the object side of fifth lens is set as tenth surface, the image side of fifth lens is set as eleventh surface, the object side of tenth lens is set as nineteenth surface, the image side of tenth lens is set as twentieth surface, seventh surface, eighth surface, tenth surface, eleventh surface, nineteenth surface and twentieth surface are all set as even aspheric surface;Optimized configuration is set by six even aspheric surfaces, optical grade non-distortion imaging is realized, the barrel distortion problem of traditional wide-angle lens is avoided, and straight line object can still maintain straight line characteristics after imaging.

Description

Technical Field

[0001] This utility model relates to the field of optical imaging technology, and in particular to a low-distortion aspherical optical lens. Background Technology

[0002] In the field of optical imaging, especially in wide-angle lens applications, distortion has always been a key factor affecting image quality. Traditional wide-angle lenses commonly suffer from barrel distortion, causing straight lines to bend and edge objects to deform in images. To address this problem, existing technologies typically employ the following two solutions:

[0003] One approach is to correct aberrations using a combination of multiple spherical lenses. However, this method requires precise matching of multiple convex and concave lenses, resulting in a complex lens structure, large size, high cost, and limited correction effectiveness. The second approach is to use software post-processing for distortion correction. However, this method introduces image processing latency, making it unsuitable for applications with high real-time requirements, such as autonomous driving and robot navigation.

[0004] Meanwhile, traditional wide-angle lenses also suffer from reduced edge resolution, resulting in blurred image edge details that affect measurement accuracy and target recognition accuracy. Furthermore, existing lenses present an irreconcilable contradiction in balancing wide field of view and low distortion performance, failing to meet the demands of industrial inspection for high definition and high geometric accuracy.

[0005] The emergence of aspherical lenses has provided a new approach to solving the above problems. By adjusting the curvature of the lens surface, they can effectively compensate for various aberrations, achieving the correction effect of traditional multiple spherical lenses with just one aspherical lens. However, the application of aspherical lenses in current technology is not optimized enough, especially in the combination design of multiple aspherical lenses, material selection, and parameter matching, where there is still room for improvement. Utility Model Content

[0006] The technical problem to be solved by this utility model is that existing wide-angle lenses suffer from severe distortion, complex structure, high cost, poor real-time performance, and low edge resolution.

[0007] To address the aforementioned technical problems, this invention provides an aspherical optical lens with a large field of view, low distortion, high resolution, and compact structure. The technical solution adopted by this invention is: a low-distortion aspherical optical lens.

[0008] Along an optical axis from the object side to the image side, the lens consists of a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, and a tenth lens.

[0009] The object-side surface of the fourth lens is configured as the seventh surface, and the image-side surface of the fourth lens is configured as the eighth surface. Both the seventh surface and the eighth surface are configured as convex surfaces.

[0010] The object-side surface of the fifth lens is configured as the tenth surface, and the image-side surface of the fifth lens is configured as the eleventh surface. Both the tenth surface and the eleventh surface are concave.

[0011] The object-side surface of the tenth lens is configured as the nineteenth surface, the image-side surface of the tenth lens is configured as the twentieth surface, the nineteenth surface is configured as a convex surface, and the twentieth surface is configured as a concave surface.

[0012] The seventh, eighth, tenth, eleventh, nineteenth, and twentieth surfaces are all configured as even-order aspherical surfaces.

[0013] Furthermore, the surface shape equation of the even-order aspherical surface is set as follows:

[0014] ;

[0015] Where c is the curvature, and c = 1 / R, R is the radius of curvature, and K is the quadratic surface constant. , is a higher-order aspherical coefficient, and r is the radial coordinate.

[0016] Furthermore, the radius of curvature of the seventh surface is set to 12.73 mm, its thickness is set to 1.581 mm, its quadratic surface constant K is set to 4.584, its aspheric coefficient A4 is set to 1.416E-3±1E-5, its aspheric coefficient A6 is set to -1.107E-4±1E-5, its aspheric coefficient A8 is set to 6.702E-5±1E-6, and its aspheric coefficient A10 is set to -9.735E-6±1E-7.

[0017] Furthermore, the radius of curvature of the eighth surface is set to -16.465 mm, its thickness is set to 0.041 mm, its quadratic surface constant K is set to 32.503, its aspheric coefficient A4 is set to -2.311E-3±1E-5, its aspheric coefficient A6 is set to -2.525E-4±1E-5, its aspheric coefficient A8 is set to -1.482E-5±1E-6, and its aspheric coefficient A10 is set to -2.464E-6±1E-7.

[0018] Furthermore, the radius of curvature of the tenth surface is set to -11.006 mm, its thickness is set to 0.830 mm, its quadratic surface constant K is set to 14, its aspheric coefficient A4 is set to -3.828E-3±2.5E-5, its aspheric coefficient A6 is set to -7.477E-4±1E-5, its aspheric coefficient A8 is set to 4.251E-5±1E-6, and its aspheric coefficient A10 is set to -7.642E-6±1E-7.

[0019] Furthermore, the radius of curvature of the eleventh surface is set to 67.118 mm, its thickness is set to 0.726 mm, its quadratic surface constant K is set to 200, its aspheric coefficient A4 is set to 6.117E-4±2.5E-5, its aspheric coefficient A6 is set to -1.159E-4±5E-6, its aspheric coefficient A8 is set to 2.417E-5±1E-6, and its aspheric coefficient A10 is set to -5.162E-7±1E-7.

[0020] Furthermore, the radius of curvature of the nineteenth surface is set to 9.125 mm, its thickness is set to 1.644 mm, its quadratic surface constant K is set to 0.283, its aspheric coefficient A4 is set to 3.181E-4±1E-5, its aspheric coefficient A6 is set to 4.370E-5±1E-6, its aspheric coefficient A8 is set to 3.105E-8±1E-9, and its aspheric coefficient A10 is set to 3.177E-8±1E-9.

[0021] Furthermore, the radius of curvature of the twentieth surface is set to 39.252 mm, its thickness is set to 3.973 mm, its quadratic surface constant K is set to 60.885, its aspheric coefficient A4 is set to 1.048E-3±2.5E-5, its aspheric coefficient A6 is set to 7.102E-5±1E-6, its aspheric coefficient A8 is set to -7.623E-7±1E-8, and its aspheric coefficient A10 is set to 1.692E-7±1E-8.

[0022] Furthermore, they are arranged along the optical axis from the object side to the image side.

[0023] The object-side surface of the first lens is configured as a first surface, and the image-side surface of the first lens is configured as a second surface. The first surface is configured as a convex surface, and the second surface is configured as a concave surface.

[0024] The object-side surface of the second lens is configured as a third surface, and the image-side surface of the second lens is configured as a fourth surface. The third surface is configured as a convex surface, and the fourth surface is configured as a concave surface.

[0025] The object-side surface of the third lens is configured as a fifth surface, and the image-side surface of the third lens is configured as a sixth surface. The fifth surface is configured as a convex surface, and the sixth surface is configured as a concave surface.

[0026] The object-side surface of the sixth lens is configured as the twelfth surface, and the image-side surface of the sixth lens is configured as the thirteenth surface. Both the twelfth and thirteenth surfaces are convex surfaces.

[0027] The object-side surface of the seventh lens is configured as the fourteenth surface, the image-side surface of the seventh lens is configured as the fifteenth surface, the fourteenth surface is configured as a concave surface, and the fifteenth surface is configured as a convex surface;

[0028] The object-side surface of the eighth lens is configured as the sixteenth surface, and the image-side surface of the eighth lens is configured as the seventeenth surface. Both the sixteenth and seventeenth surfaces are convex surfaces.

[0029] The object-side surface of the ninth lens is configured as the seventeenth surface, and the image-side surface of the ninth lens is configured as the eighteenth surface. The seventeenth surface is configured as a convex surface, and the eighteenth surface is configured as a concave surface.

[0030] The first surface, the second surface, the third surface, the fourth surface, the fifth surface, the sixth surface, the twelfth surface, the thirteenth surface, the fourteenth surface, the fifteenth surface, the sixteenth surface, the seventeenth surface, and the eighteenth surface are all set as standard spherical surfaces.

[0031] Furthermore, a ninth surface is provided between the eighth surface and the tenth surface, and an aperture stop is provided on the ninth surface.

[0032] The beneficial effects of this invention are as follows: 1) By optimizing the configuration of six even-order aspherical surfaces, optically distortion-free imaging is achieved, avoiding the barrel distortion problem of traditional wide-angle lenses, and ensuring that straight objects retain their straight-line characteristics after imaging. 2) It can be applied to sensors such as the AR2020, achieving a resolution of 120 lp / mm, with significantly better edge resolution than traditional designs. 3) By employing optical methods, distortion-free imaging can be directly achieved, eliminating the delay caused by software correction and meeting the needs of applications with high real-time requirements. 4) By replacing the traditional multi-spherical lens combination aberration correction method with aspherical lenses, the lens structure is simplified and its size and weight are reduced while ensuring image quality. 5) It can correct for visible and near-infrared bands, supporting multispectral imaging analysis. Attached Figure Description

[0033] Figure 1 A structural diagram of one embodiment of this utility model.

[0034] Figure 2 A structural cross-sectional view of an embodiment of this utility model.

[0035] Figure 3 A schematic diagram of the lens structure layout of an embodiment of this utility model.

[0036] Figure 4 MTF curve of an embodiment of the present invention.

[0037] Figure 5 The distortion curve diagram is provided for one embodiment of this utility model.

[0038] Figure 6 A transverse chromatic difference curve for different wavelengths of light provided in an embodiment of this utility model.

[0039] Label Explanation:

[0040] 1. First lens; 2. Second lens; 3. Third lens; 4. Fourth lens; 5. Fifth lens; 6. Sixth lens; 7. Seventh lens; 8. Eighth lens; 9. Ninth lens; 10. Tenth lens. Detailed Implementation

[0041] To explain in detail the technical content, objectives, and effects of this utility model, the following description is provided in conjunction with the embodiments and accompanying drawings.

[0042] Please refer to Figures 1 to 6 A low-distortion aspherical optical lens includes, along an optical axis from the object side to the image side, a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, an aperture stop, a fifth lens 5, a sixth lens 6, a seventh lens 7, an eighth lens 8, a ninth lens 9, and a tenth lens 10.

[0043] The components are arranged along the optical axis from the object side to the image side.

[0044] The object side of the first lens 1 is set as the first surface, and the image side of the first lens 1 is set as the second surface. The first surface is set as a convex surface, and the second surface is set as a concave surface. The first surface and the second surface are standard spherical surfaces, and their material is TAFD34 optical glass.

[0045] The object side of the second lens 2 is configured as a third surface, and the image side of the second lens 2 is configured as a fourth surface. The third surface is configured as a convex surface, and the fourth surface is configured as a concave surface. The third surface and the fourth surface are standard spherical surfaces, and the material is H-LAF50B optical glass.

[0046] The object side of the third lens 3 is configured as the fifth surface, and the image side of the third lens 3 is configured as the sixth surface. The fifth surface is configured as a convex surface, and the sixth surface is configured as a concave surface. The fifth surface and the sixth surface are standard spherical surfaces, and their material is E-LAF7 optical glass.

[0047] The object side of the fourth lens 4 is configured as the seventh surface, and the image side of the fourth lens 4 is configured as the eighth surface. Both the seventh and eighth surfaces are convex surfaces. The seventh and eighth surfaces are even-order aspherical surfaces, and their material is DZK-79 optical glass.

[0048] A ninth surface is disposed between the eighth surface and the tenth surface, and the ninth surface is configured as an aperture stop.

[0049] The object side of the fifth lens 5 is set as the tenth surface, and the image side of the fifth lens 5 is set as the eleventh surface. Both the tenth and eleventh surfaces are concave. The tenth and eleventh surfaces are even-order aspherical surfaces, and their material is D-ZF10 optical glass.

[0050] The object side of the sixth lens 6 is set as the twelfth surface, and the image side of the sixth lens 6 is set as the thirteenth surface. Both the twelfth and thirteenth surfaces are convex surfaces. The twelfth and thirteenth surfaces are standard spherical surfaces, and their material is H-ZLAF73 optical glass.

[0051] The object-side surface of the seventh lens 7 is set as the fourteenth surface, and the image-side surface of the seventh lens 7 is set as the fifteenth surface. The fourteenth surface is set as a concave surface, and the fifteenth surface is set as a convex surface. The fourteenth surface and the fifteenth surface are standard spherical surfaces, and their material is FCD500 optical glass.

[0052] The object side of the eighth lens 8 is configured as the sixteenth surface, and the image side of the eighth lens 8 is configured as the seventeenth surface. Both the sixteenth and seventeenth surfaces are convex surfaces. The sixteenth surface is a standard spherical surface made of H-LAK7A optical glass, and the seventeenth surface is a standard spherical surface made of H-ZF52 optical glass.

[0053] The object side of the ninth lens 9 is set as the seventeenth surface, and the image side of the ninth lens 9 is set as the eighteenth surface. The seventeenth surface is set as a convex surface, and the eighteenth surface is set as a concave surface. The seventeenth surface and the eighteenth surface are standard spherical surfaces, and their material is H-ZF52 optical glass.

[0054] The object side of the tenth lens 10 is set as the nineteenth surface, and the image side of the tenth lens 10 is set as the twentieth surface. The nineteenth surface is set as a convex surface, and the twentieth surface is set as a concave surface. The nineteenth surface and the twentieth surface are even-order aspherical surfaces, and the material is MP-TAC80-60 optical glass.

[0055] The radius of curvature, center thickness, and air gap of each lens from the first lens 1 to the tenth lens 10 are determined by optical optimization, which enables the lens to achieve a large aperture of F2.0 in an extremely compact size with TTL ≤ 6.2f (29 / 4.71≈6.16), i.e., a total axial length of 29.01mm.

[0056] Specifically, the surface shape equation of the even-order aspherical surface is set as follows:

[0057] ;

[0058] Where c is the curvature, and c = 1 / R, R is the radius of curvature, and K is the quadratic surface constant. , is a higher-order aspherical coefficient, and r is the radial coordinate.

[0059] Example 1:

[0060] A low-distortion aspherical optical lens includes, along an optical axis from the object side to the image side, a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, an aperture stop, a fifth lens 5, a sixth lens 6, a seventh lens 7, an eighth lens 8, a ninth lens 9, and a tenth lens 10.

[0061] The components are arranged along the optical axis from the object side to the image side.

[0062] The object side of the first lens 1 is set as the first surface, and the image side of the first lens 1 is set as the second surface. The first surface is set as a convex surface, and the second surface is set as a concave surface. The first surface and the second surface are standard spherical surfaces, and their material is TAFD34 optical glass.

[0063] The object side of the second lens 2 is configured as a third surface, and the image side of the second lens 2 is configured as a fourth surface. The third surface is configured as a convex surface, and the fourth surface is configured as a concave surface. The third surface and the fourth surface are standard spherical surfaces, and the material is H-LAF50B optical glass.

[0064] The object side of the third lens 3 is configured as the fifth surface, and the image side of the third lens 3 is configured as the sixth surface. The fifth surface is configured as a convex surface, and the sixth surface is configured as a concave surface. The fifth surface and the sixth surface are standard spherical surfaces, and their material is E-LAF7 optical glass.

[0065] The object side of the fourth lens 4 is configured as the seventh surface, and the image side of the fourth lens 4 is configured as the eighth surface. Both the seventh and eighth surfaces are convex surfaces. The seventh and eighth surfaces are even-order aspherical surfaces, and their material is DZK-79 optical glass.

[0066] A ninth surface is provided between the eighth surface and the tenth surface. The ninth surface is set as an aperture stop. Its precise position can be obtained through a large number of calculations by optical design software, and it is one of the key results that can make the overall imaging quality of the lens optimal.

[0067] The object side of the fifth lens 5 is set as the tenth surface, and the image side of the fifth lens 5 is set as the eleventh surface. Both the tenth and eleventh surfaces are concave. The tenth and eleventh surfaces are even-order aspherical surfaces, and their material is D-ZF10 optical glass.

[0068] The object side of the sixth lens 6 is set as the twelfth surface, and the image side of the sixth lens 6 is set as the thirteenth surface. Both the twelfth and thirteenth surfaces are convex surfaces. The twelfth and thirteenth surfaces are standard spherical surfaces, and their material is H-ZLAF73 optical glass.

[0069] The object-side surface of the seventh lens 7 is set as the fourteenth surface, and the image-side surface of the seventh lens 7 is set as the fifteenth surface. The fourteenth surface is set as a concave surface, and the fifteenth surface is set as a convex surface. The fourteenth surface and the fifteenth surface are standard spherical surfaces, and their material is FCD500 optical glass.

[0070] The object side of the eighth lens 8 is configured as the sixteenth surface, and the image side of the eighth lens 8 is configured as the seventeenth surface. Both the sixteenth and seventeenth surfaces are convex surfaces. The sixteenth surface is a standard spherical surface made of H-LAK7A optical glass, and the seventeenth surface is a standard spherical surface made of H-ZF52 optical glass.

[0071] The object side of the ninth lens 9 is set as the seventeenth surface, and the image side of the ninth lens 9 is set as the eighteenth surface. The seventeenth surface is set as a convex surface, and the eighteenth surface is set as a concave surface. The seventeenth surface and the eighteenth surface are standard spherical surfaces, and their material is H-ZF52 optical glass.

[0072] The object side of the tenth lens 10 is set as the nineteenth surface, and the image side of the tenth lens 10 is set as the twentieth surface. The nineteenth surface is set as a convex surface, and the twentieth surface is set as a concave surface. The nineteenth surface and the twentieth surface are even-order aspherical surfaces, and the material is MP-TAC80-60 optical glass.

[0073] Detailed optical data for this specific embodiment are shown in Table 1.

[0074] Table 1. Detailed optical data for Example 1:

[0075]

[0076] The lens has an effective focal length of 4.71mm and an aperture of F-number of 2.0, and can be used with 1 / 1.8-inch image sensors.

[0077] Example 2:

[0078] The surface contours and materials of the lenses in this embodiment are the same as those in Embodiment 1, except for the following parameters.

[0079] Detailed optical data for this specific embodiment are shown in Table 2.

[0080] Table 2 shows the detailed optical data for Example 2:

[0081]

[0082] Furthermore, referring to Figure 4 As shown, the modulation transfer function value at 120 lp / mm is greater than 0.3.

[0083] Furthermore, referring to Figure 5 As shown, the distortion is less than 2% across the entire field of view.

[0084] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent modifications made based on the content of this utility model specification and drawings, or direct or indirect applications in related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A low-distortion aspherical optical lens, characterized in that, Along an optical axis from the object side to the image side, the lens consists of a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, and a tenth lens. The object-side surface of the fourth lens is configured as the seventh surface, and the image-side surface of the fourth lens is configured as the eighth surface. Both the seventh surface and the eighth surface are configured as convex surfaces. The object-side surface of the fifth lens is configured as the tenth surface, and the image-side surface of the fifth lens is configured as the eleventh surface. Both the tenth surface and the eleventh surface are concave. The object-side surface of the tenth lens is configured as the nineteenth surface, the image-side surface of the tenth lens is configured as the twentieth surface, the nineteenth surface is configured as a convex surface, and the twentieth surface is configured as a concave surface. The seventh, eighth, tenth, eleventh, nineteenth, and twentieth surfaces are all configured as even-order aspherical surfaces.

2. The low-distortion aspherical optical lens according to claim 1, characterized in that: The surface equation of the even-order aspherical surface is set as follows: ； Where c is the curvature, and c = 1 / R, R is the radius of curvature, and K is the quadratic surface constant. , is a higher-order aspherical coefficient, and r is the radial coordinate.

3. The low-distortion aspherical optical lens according to claim 1, characterized in that: The radius of curvature of the seventh surface is set to 12.73 mm, its thickness is set to 1.581 mm, its quadratic surface constant K is set to 4.584, its aspheric coefficient A4 is set to 1.416E-3±1E-5, its aspheric coefficient A6 is set to -1.107E-4±1E-5, its aspheric coefficient A8 is set to 6.702E-5±1E-6, and its aspheric coefficient A10 is set to -9.735E-6±1E-7.

4. The low-distortion aspherical optical lens according to claim 1, characterized in that: The radius of curvature of the eighth surface is set to -16.465 mm, its thickness is set to 0.041 mm, its quadratic surface constant K is set to 32.503, its aspheric coefficient A4 is set to -2.311E-3±1E-5, its aspheric coefficient A6 is set to -2.525E-4±1E-5, its aspheric coefficient A8 is set to -1.482E-5±1E-6, and its aspheric coefficient A10 is set to -2.464E-6±1E-7.

5. The low-distortion aspherical optical lens according to claim 1, characterized in that: The radius of curvature of the tenth surface is set to -11.006 mm, its thickness is set to 0.830 mm, its quadratic surface constant K is set to 14, its aspheric coefficient A4 is set to -3.828E-3±2.5E-5, its aspheric coefficient A6 is set to -7.477E-4±1E-5, its aspheric coefficient A8 is set to 4.251E-5±1E-6, and its aspheric coefficient A10 is set to -7.642E-6±1E-7.

6. The low-distortion aspherical optical lens according to claim 1, characterized in that: The radius of curvature of the eleventh surface is set to 67.118 mm, its thickness is set to 0.726 mm, its quadratic surface constant K is set to 200, its aspheric coefficient A4 is set to 6.117E-4±2.5E-5, its aspheric coefficient A6 is set to -1.159E-4±5E-6, its aspheric coefficient A8 is set to 2.417E-5±1E-6, and its aspheric coefficient A10 is set to -5.162E-7±1E-7.

7. The low-distortion aspherical optical lens according to claim 1, characterized in that: The radius of curvature of the nineteenth surface is set to 9.125 mm, its thickness is set to 1.644 mm, its quadratic surface constant K is set to 0.283, its aspheric coefficient A4 is set to 3.181E-4±1E-5, its aspheric coefficient A6 is set to 4.370E-5±1E-6, its aspheric coefficient A8 is set to 3.105E-8±1E-9, and its aspheric coefficient A10 is set to 3.177E-8±1E-9.

8. The low-distortion aspherical optical lens according to claim 1, characterized in that: The radius of curvature of the twentieth surface is set to 39.252 mm, its thickness is set to 3.973 mm, its quadratic surface constant K is set to 60.885, its aspheric coefficient A4 is set to 1.048E-3±2.5E-5, its aspheric coefficient A6 is set to 7.102E-5±1E-6, its aspheric coefficient A8 is set to -7.623E-7±1E-8, and its aspheric coefficient A10 is set to 1.692E-7±1E-8.

9. The low-distortion aspherical optical lens according to any one of claims 1 to 8, characterized in that: Arranged along the optical axis from the object side to the image side, The object-side surface of the first lens is configured as a first surface, and the image-side surface of the first lens is configured as a second surface. The first surface is configured as a convex surface, and the second surface is configured as a concave surface. The object-side surface of the second lens is configured as a third surface, and the image-side surface of the second lens is configured as a fourth surface. The third surface is configured as a convex surface, and the fourth surface is configured as a concave surface. The object-side surface of the third lens is configured as a fifth surface, and the image-side surface of the third lens is configured as a sixth surface. The fifth surface is configured as a convex surface, and the sixth surface is configured as a concave surface. The object-side surface of the sixth lens is configured as the twelfth surface, and the image-side surface of the sixth lens is configured as the thirteenth surface. Both the twelfth and thirteenth surfaces are convex surfaces. The object-side surface of the seventh lens is configured as the fourteenth surface, the image-side surface of the seventh lens is configured as the fifteenth surface, the fourteenth surface is configured as a concave surface, and the fifteenth surface is configured as a convex surface; The object-side surface of the eighth lens is configured as the sixteenth surface, and the image-side surface of the eighth lens is configured as the seventeenth surface. Both the sixteenth and seventeenth surfaces are convex surfaces. The object-side surface of the ninth lens is configured as the seventeenth surface, and the image-side surface of the ninth lens is configured as the eighteenth surface. The seventeenth surface is configured as a convex surface, and the eighteenth surface is configured as a concave surface. The first surface, the second surface, the third surface, the fourth surface, the fifth surface, the sixth surface, the twelfth surface, the thirteenth surface, the fourteenth surface, the fifteenth surface, the sixteenth surface, the seventeenth surface, and the eighteenth surface are all set as standard spherical surfaces.

10. The low-distortion aspherical optical lens according to claim 9, characterized in that: A ninth surface is provided between the eighth surface and the tenth surface, and an aperture stop is provided on the ninth surface.

Images