An intelligent traffic lens with low distortion, large target area, high light transmission and high resolution

Abstract

The present invention discloses an intelligent traffic lens with low distortion, large target area, large light transmission and high resolution. The optical system of the intelligent traffic lens comprises a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, an aperture C, a seventh lens L7, an eighth lens L8, a ninth lens L9 and an image plane IMG, which are arranged in sequence along an incident light path. The first lens L1 to the sixth lens L6 form a front lens group; the seventh lens L7 to the ninth lens L9 form a rear lens group; the third lens L3 and the fourth lens L4 form a first cemented lens group; the fifth lens L5 and the sixth lens L6 form a second cemented lens group; the traffic lens satisfies the following conditional formula: 1.1≤(f G1 ×f / f G2 )×tan(FOV / 4)≤1.5. The traffic lens of the present invention has the characteristics of low distortion, large target area, large light transmission and high resolution.

Description

Technical Field

[0001] The present invention belongs to the technical field of optical lenses, and in particular relates to an intelligent traffic lens with low distortion, large target area, large light transmission and high resolution. Background Art

[0002] In intelligent transportation systems, the accuracy of information acquisition directly depends on the precise acquisition of image data by the front-end camera and its equipped lens.

[0003] Given the system's special performance requirements, the configured lens must exhibit performance characteristics beyond the norm, specifically low distortion, large target area, large light transmission and high resolution.

[0004] However, the current intelligent traffic lenses on the market still have shortcomings in fully meeting the requirements of low distortion, large target area, large light transmission and high resolution. At the same time, the market demand for lenses with these high-performance features is continuing to rise.

[0005] Therefore, developing a lens that can fully meet the above requirements has become an urgent task. Summary of the Invention

[0006] In view of the deficiencies in the prior art, the present invention provides an intelligent traffic lens with low distortion, large target area, large light transmission and high resolution.

[0007] To achieve the above objectives, the present invention provides the following technical solution: an intelligent traffic lens with low distortion, large target area, large light transmission and high resolution, wherein the optical system of the traffic lens comprises a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, an aperture C, a seventh lens L7, an eighth lens L8, a ninth lens L9 and an image plane IMG, which are arranged in sequence along the incident light path.

[0008] The first lens L1 is a positive meniscus lens with its convex surface facing the object;

[0009] The second lens L2 is a biconvex positive lens or a meniscus positive lens with the convex surface facing the object;

[0010] The third lens L3 is a biconvex positive lens;

[0011] The fourth lens L4 is a biconcave negative lens;

[0012] The fifth lens L5 is a biconcave negative lens;

[0013] The sixth lens L6 is a biconvex positive lens;

[0014] The seventh lens L7 is a biconvex positive lens;

[0015] The eighth lens L8 is a positive meniscus lens with its convex surface facing the object;

[0016] The ninth lens L9 is a meniscus negative lens or a biconcave negative lens with its concave surface facing the image side;

[0017] The first lens L1 to the sixth lens L6 form a front lens group; the seventh lens L7 to the ninth lens L9 form a rear lens group.

[0018] The third lens L3 and the fourth lens L4 form a first cemented lens group; the fifth lens L5 and the sixth lens L6 form a second cemented lens group;

[0019] The traffic lens satisfies the following condition: 1.1≤(f G1 ×f / f G2 )×tan(FOV / 4)≤1.5, where f G1 represents the effective focal length of the first cemented lens group; f G2 represents the effective focal length of the second cemented lens group; f represents the effective focal length of the traffic lens; FOV represents the maximum field of view of the traffic lens.

[0020] As a specific implementation, the traffic lens also satisfies the following condition: 6.0≤|f u1 / f u2 |≤7.3, where f u1 Indicates the effective focal length of the front lens group; f u2 Indicates the effective focal length of the rear lens group.

[0021] As a specific implementation, the traffic lens further satisfies the following condition: 1.1≤FOV / CRA≤1.3, wherein FOV represents the maximum field of view of the traffic lens; and CRA represents the main ray angle of the traffic lens.

[0022] As a specific implementation, the traffic lens further satisfies the following conditional formula: 0.05≤D / TTL≤0.11, where D represents the sum of the distances between the aperture C and its front and rear adjacent lenses; and TTL represents the total optical length of the traffic lens.

[0023] As a specific implementation, the ninth lens L9 satisfies the following conditions: 0.8≤(R 91 -R 92 ) / (R 91 +R 92 )≤1.1, where R 91 R represents the curvature radius of the object side of the ninth lens L9; 92 It represents the curvature radius of the image-side surface of the ninth lens L9.

[0024] As a specific implementation, the traffic lens also satisfies the following condition: 53≤|V d3 -V d4 |≤54, where Vd3 V represents the Abbe number of the third lens L3; d4 It represents the Abbe number of fourth lens L4.

[0025] As a specific embodiment, when the first lens L1 is a positive meniscus lens with its convex surface facing the object; the second lens L2 is a positive meniscus lens with its convex surface facing the object; the third lens L3 is a biconvex positive lens; the fourth lens L4 is a biconcave negative lens; the fifth lens L5 is a biconcave negative lens; the sixth lens L6 is a biconvex positive lens; the seventh lens L7 is a biconvex positive lens; the eighth lens L8 is a positive meniscus lens with its convex surface facing the object; and the ninth lens L9 is a negative meniscus lens with its concave surface facing the image side, the air distance from the first lens L1 to the second lens L2 is 11.9695 mm; The air distance between the second lens L2 and the third lens L3 is 0.1000mm; the air distance between the fourth lens L4 and the fifth lens L5 is 5.0987mm; the air distance between the sixth lens L6 and the aperture C is 1.9249mm; the air distance between the aperture C and the seventh lens L7 is 2.5000mm; the air distance between the seventh lens L7 and the eighth lens L8 is 0.1000mm; the air distance between the eighth lens L8 and the ninth lens L9 is 0.6895mm; and the air distance between the ninth lens L9 and the image plane IMG is 17.2737mm.

[0026] As a specific embodiment, when the first lens L1 is a positive meniscus lens with its convex surface facing the object side; the second lens L2 is a biconvex positive lens; the third lens L3 is a biconvex positive lens; the fourth lens L4 is a biconcave negative lens; the fifth lens L5 is a biconcave negative lens; the sixth lens L6 is a biconvex positive lens; the seventh lens L7 is a biconvex positive lens; the eighth lens L8 is a positive meniscus lens with its convex surface facing the object side; and the ninth lens L9 is a negative meniscus lens with its concave surface facing the image side, the air distance from the first lens L1 to the second lens L2 is 12.6475 mm; the second lens The air distance from L2 to the third lens L3 is 0.0931mm; the air distance from the fourth lens L4 to the fifth lens L5 is 4.5468mm; the air distance from the sixth lens L6 to the aperture C is 1.7186mm; the air distance from the aperture C to the seventh lens L7 is 6.8206mm; the air distance from the seventh lens L7 to the eighth lens L8 is 0.1000mm; the air distance from the eighth lens L8 to the ninth lens L9 is 0.6965mm; and the air distance from the ninth lens L9 to the image plane IMG is 15.5862mm.

[0027] As a specific embodiment, when the first lens L1 is a positive meniscus lens with its convex surface facing the object; the second lens L2 is a positive meniscus lens with its convex surface facing the object; the third lens L3 is a biconvex positive lens; the fourth lens L4 is a biconcave negative lens; the fifth lens L5 is a biconcave negative lens; the sixth lens L6 is a biconvex positive lens; the seventh lens L7 is a biconvex positive lens; the eighth lens L8 is a positive meniscus lens with its convex surface facing the object; and the ninth lens L9 is a biconcave negative lens, the air distance from the first lens L1 to the second lens L2 is 11.3178 mm; the second lens The air distance from L2 to the third lens L3 is 0.1000mm; the air distance from the fourth lens L4 to the fifth lens L5 is 5.1441mm; the air distance from the sixth lens L6 to the aperture C is 3.1059mm; the air distance from the aperture C to the seventh lens L7 is 4.0339mm; the air distance from the seventh lens L7 to the eighth lens L8 is 0.1000mm; the air distance from the eighth lens L8 to the ninth lens L9 is 0.8268mm; and the air distance from the ninth lens L9 to the image plane IMG is 14.9262mm.

[0028] Compared with the existing technology, the present invention provides an intelligent traffic lens with low distortion, large target area, high light transmission and high resolution, which has the following beneficial effects:

[0029] 1) The present invention maintains the optical performance of the lens while achieving a large target area by rationally allocating the positions of the lenses in the optical system;

[0030] 2) The present invention optimizes optical performance and reduces chromatic aberration of imaging by introducing a cemented lens into the imaging system;

[0031] 3) The present invention ensures image clarity by rationally allocating the positions of lenses with different optical powers;

[0032] 4) By reasonably distributing the optical power of the glued lens, that is, requiring 1.1≤(f G1 ×f / f G2 )×tan(FOV / 4)≤1.5, achieving the requirements of low distortion and low chromatic aberration;

[0033] 5) By reasonably allocating the optical power of the front and rear groups, that is, requiring 6.0≤|f u1 / f u2 |≤7.3, to meet the requirement of clear imaging on a large target surface;

[0034] 6) By properly adjusting the distance between the aperture and the adjacent lenses, that is, requiring 0.05≤D / TTL≤0.11, the demand for large light transmission can be met. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1This is the optical path diagram of the intelligent traffic lens with low distortion, large target area, high light transmission and high resolution in Example 1;

[0036] Figure 2 This is the MTF curve of the low-distortion, large-target-area, high-light-throughput, and high-resolution intelligent traffic lens in the visible light band in Example 1;

[0037] Figure 3 This is a field curvature distortion diagram of the low-distortion, large-target-area, high-light-throughput, and high-resolution intelligent traffic lens in Example 1;

[0038] Figure 4 This is a relative illumination curve of the low-distortion, large-target-area, high-light-throughput, and high-resolution intelligent traffic lens in Example 1;

[0039] Figure 5 This is a graph showing the axial aberration of the low-distortion, large-target-area, high-light-throughput, and high-resolution intelligent traffic lens in the visible light band in Example 1;

[0040] Figure 6 This is a vertical axis chromatic aberration curve in the visible light band of the intelligent traffic lens with low distortion, large target area, high light transmission and high resolution in Example 1;

[0041] Figure 7 This is the optical path diagram of the intelligent traffic lens with low distortion, large target area, high light transmission and high resolution in Example 2;

[0042] Figure 8 This is the MTF curve of the low-distortion, large-target-area, high-light-throughput, and high-resolution intelligent traffic lens in the visible light band in Example 2;

[0043] Figure 9 This is a field curvature distortion diagram of the low-distortion, large-target-area, high-light-throughput, and high-resolution intelligent traffic lens in Example 2;

[0044] Figure 10 This is a relative illumination curve diagram of the intelligent traffic lens with low distortion, large target area, high light transmission and high resolution in Example 2;

[0045] Figure 11 This is a graph showing the axial aberration of the low-distortion, large-target-area, high-light-throughput, and high-resolution intelligent traffic lens in the visible light band in Example 2;

[0046] Figure 12 This is a vertical axis chromatic aberration curve in the visible light band of the low-distortion, large-target-area, high-light-throughput, high-resolution intelligent traffic lens in Example 2;

[0047] Figure 13 This is the optical path diagram of the intelligent traffic lens with low distortion, large target area, high light transmission and high resolution in Example 3;

[0048] Figure 14This is the MTF curve of the low-distortion, large-target-area, high-light-throughput, and high-resolution intelligent traffic lens in the visible light band in Example 3;

[0049] Figure 15 This is a field curvature distortion diagram of the low-distortion, large-target-area, high-light-throughput, and high-resolution intelligent traffic lens in Example 3;

[0050] Figure 16 This is a relative illumination curve of the intelligent traffic lens with low distortion, large target area, high light transmission and high resolution in Example 3;

[0051] Figure 17 This is a graph showing the axial aberration of the low-distortion, large-target-area, high-light-throughput, and high-resolution intelligent traffic lens in the visible light band in Example 3;

[0052] Figure 18 This is a vertical axis chromatic aberration curve in the visible light band of the low-distortion, large target area, high-light transmission, and high-resolution intelligent traffic lens in Example 3. DETAILED DESCRIPTION

[0053] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments 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 are within the scope of protection of the present invention.

[0054] Disclosed is an intelligent traffic lens with low distortion, a large target area, large light transmission, and high resolution. The optical system of the traffic lens comprises a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, an aperture C, a seventh lens L7, an eighth lens L8, a ninth lens L9, and an image plane IMG, which are sequentially arranged along an incident light path. The first lens L1 is a positive meniscus lens with a convex surface facing the object; the second lens L2 is a biconvex positive lens or a positive meniscus lens with a convex surface facing the object; the third lens L3 is a biconvex positive lens; the fourth lens L4 is a biconcave negative lens; the fifth lens L5 is a biconcave negative lens; the sixth lens L6 is a biconvex positive lens; the seventh lens L7 is a biconvex positive lens; the eighth lens L8 is a positive meniscus lens with a convex surface facing the object; and the ninth lens L9 is a negative meniscus lens or a biconcave negative lens with a concave surface facing the image.

[0055] Among them, the first lens L1 to the sixth lens L6 form the front lens group; the seventh lens L7 to the ninth lens L9 form the rear lens group; the third lens L3 and the fourth lens L4 form the first cemented lens group; the fifth lens L5 and the sixth lens L6 form the second cemented lens group.

[0056] The curved shape of the first lens L1 helps the lens capture light at a large angle.

[0057] The second lens L2 can focus the light collected by the first lens L1, so that the light smoothly transitions to the rear optical system, and reasonably controls the optical focal length.

[0058] The third lens L3 and the fourth lens L4 form a first cemented lens group. By using a combination of high and low refractive index lenses, it is beneficial to the rapid transition of the front light and compensate for chromatic aberration.

[0059] The fifth lens L5 and the sixth lens L6 form the second cemented lens group, which can diverge light while balancing the spherical aberration and axial chromatic aberration of the optical system.

[0060] The aperture C is placed between the cemented lens and the seventh lens L7 to control the imaging quality and the performance of the optical system by limiting the propagation range and direction of the light beam.

[0061] The seventh lens L7 can focus the light collected by the second cemented lens group, and work together with the aperture to optimize the depth of field and imaging range of the lens.

[0062] The eighth lens L8 can further focus the light collected by the seventh lens L7 and correct the aberrations to optimize the imaging performance of the lens group.

[0063] The ninth lens L9 can diverge the light collected by the eighth lens L8, correct the field curvature of the lens, and fine-tune the focal length of the lens to improve the imaging clarity of the lens.

[0064] The lenses in the following embodiments are all made of glass with a normal refractive index.

[0065] Example 1

[0066] In the optical system of this example, the first lens L1 is a positive meniscus lens with its convex surface facing the object; the second lens L2 is a positive meniscus lens with its convex surface facing the object; the third lens L3 is a double-convex positive lens; the fourth lens L4 is a double-concave negative lens; the fifth lens L5 is a double-concave negative lens; the sixth lens L6 is a double-convex positive lens; the seventh lens L7 is a double-convex positive lens; the eighth lens L8 is a positive meniscus lens with its convex surface facing the object; and the ninth lens L9 is a negative meniscus lens with its concave surface facing the image. The third lens L3 and the fourth lens L4 form the first cemented lens group; the fifth lens L5 and the sixth lens L6 form the second cemented lens group. The optical path diagram of this traffic lens is shown in FIG. Figure 1 shown.

[0067] See Table 1, which lists the relevant parameters of each lens in this example, including the radius of curvature, thickness, refractive index of the material, and Abbe number:

[0068] Table 1

[0069]

[0070] Infinity means infinity.

[0071] In this example, the air distance between the first lens L1 and the second lens L2 is 11.9695 mm; the air distance between the second lens L2 and the third lens L3 is 0.1000 mm; the air distance between the fourth lens L4 and the fifth lens L5 is 5.0987 mm; the air distance between the sixth lens L6 and the aperture C is 1.9249 mm; the air distance between the aperture C and the seventh lens L7 is 2.5000 mm; the air distance between the seventh lens L7 and the eighth lens L8 is 0.1000 mm; the air distance between the eighth lens L8 and the ninth lens L9 is 0.6895 mm; and the air distance between the ninth lens L9 and the image plane IMG is 17.2737 mm.

[0072] The technical indicators achieved by the optical system in this example are as follows:

[0073] 1) Maximum field of view of traffic camera: FOV = 18.6°;

[0074] 2) Effective focal length of the first cemented lens group: f G1 =-49.2769mm;

[0075] 3) Effective focal length of the second cemented lens group: f G2 =-167.7638mm;

[0076] 4) Effective focal length of the front lens group: f u1 =244.3417mm;

[0077] 5) Effective focal length of the rear lens group: f u2 =33.5495mm;

[0078] 6) Chief ray angle of traffic lens: CRA = 15.6246°;

[0079] 7) Effective focal length of traffic lens: f = 48.9917mm;

[0080] 8) Total optical length of traffic lens: TTL = 83.0119mm;

[0081] 9) The sum of the distances between the aperture C and its adjacent lenses: D = 4.4249 mm;

[0082] 10) Radius of curvature of the object side of the ninth lens L9: R 91 =132.8200mm;

[0083] 11) Radius of curvature of the image-side surface of the ninth lens L9: R 92 =14.1250mm;

[0084] 12) Abbe number of the third lens L3: V d3 =81.61;

[0085] 13) Abbe number of the fourth lens L4: V d4 =27.76.

[0086] Then we get: (f G1 ×f / f G2 )×tan(FOV / 4)=1.1704;|f u1 / f u2 |=7.2830; FOV / CRA=1.1904; D / TTL=0.0533; (R 91 -R 92 ) / (R 91 +R 92 )=0.0878;|V d3 -V d4 |=53.85.

[0087] Here, by reasonably allocating the optical power of the glued lens, that is, requiring 1.1≤(f G1 ×f / f G2 )×tan(FOV / 4)≤1.5, achieving the requirements of low distortion and low chromatic aberration.

[0088] By reasonably allocating the optical power of the front and rear groups, that is, requiring 6.0≤|f u1 / f u2 |≤7.3, to meet the demand for clear imaging on large target surfaces.

[0089] By rationally allocating the positions of the lenses in the optical system, that is, requiring 1.1≤FOV / CRA≤1.3, the requirement of low distortion is achieved.

[0090] By properly adjusting the distance between the aperture and the adjacent lenses, that is, requiring 0.05≤D / TTL≤0.11, the demand for large light transmission can be met.

[0091] By reasonably setting the curvature radius of the ninth lens L9, 0.8≤(R 91 -R 92 ) / (R 91 +R 92 )≤1.1, thereby reducing the aberration of the lens and controlling the back focus of the lens.

[0092] By reasonably selecting the Abbe number of the two lenses that make up the cemented lens, that is, 53≤|V d3 -V d4 |≤54, effectively reducing the chromatic aberration of the optical system.

[0093] The final imaging effect of the lens in this example is achieved through Figure 2 The MTF graph is used to evaluate the MTF curves under each field of view. The MTF curves all decrease smoothly and have good consistency. As can be seen from the graph, the MTF value is greater than 0.45 at the spatial frequency of 60pl / mm in the edge field of view, which means that the lens has good imaging effect and resolution in the entire field of view. Figure 3 As can be seen from the field curvature distortion diagram, the distortion of the lens does not exceed 0.3%; Figure 4 It can be seen from the relative illumination curve that at the maximum field of view, the relative illumination value of the lens is greater than 0.55; Figure 5 This is the axial aberration diagram of the lens of this embodiment. It can be seen that the maximum axial aberration does not exceed 0.05mm, and the imaging quality is good; Figure 6 This is a vertical axis chromatic aberration curve. It can be seen that the vertical axis chromatic aberration is less than 3μm.

[0094] Example 2

[0095] In the optical system of this example, the first lens L1 is a positive meniscus lens with its convex surface facing the object; the second lens L2 is a biconvex positive lens; the third lens L3 is a biconvex positive lens; the fourth lens L4 is a biconcave negative lens; the fifth lens L5 is a biconcave negative lens; the sixth lens L6 is a biconvex positive lens; the seventh lens L7 is a biconvex positive lens; the eighth lens L8 is a positive meniscus lens with its convex surface facing the object; and the ninth lens L9 is a negative meniscus lens with its concave surface facing the image. The optical path diagram of this traffic lens is shown in Figure 7 shown.

[0096] See Table 2, which lists the relevant parameters of each lens in this example, including the radius of curvature, thickness, refractive index of the material, and Abbe number:

[0097] Table 2

[0098]

[0099] Infinity means infinity.

[0100] In this example, the air distance between the first lens L1 and the second lens L2 is 12.6475 mm; the air distance between the second lens L2 and the third lens L3 is 0.0931 mm; the air distance between the fourth lens L4 and the fifth lens L5 is 4.5468 mm; the air distance between the sixth lens L6 and the aperture C is 1.7186 mm; the air distance between the aperture C and the seventh lens L7 is 6.8206 mm; the air distance between the seventh lens L7 and the eighth lens L8 is 0.1000 mm; the air distance between the eighth lens L8 and the ninth lens L9 is 0.6965 mm; and the air distance between the ninth lens L9 and the image plane IMG is 15.5862 mm.

[0101] The technical indicators achieved by the optical system in this example are as follows:

[0102] 1) Maximum field of view of traffic camera: FOV = 18.6°;

[0103] 2) Effective focal length of the first cemented lens group: f G1 =-46.6871mm;

[0104] 3) Effective focal length of the second cemented lens group: f G2 =-135.5381mm;

[0105] 4) Effective focal length of the front lens group: f u1 =200.9917mm;

[0106] 5) Effective focal length of the rear lens group: f u2 =33.2502mm;

[0107] 6) Chief ray angle of traffic lens: CRA = 14.4409°;

[0108] 7) Effective focal length of traffic lens: f = 50.3984mm;

[0109] 8) Total optical length of traffic lens: TTL = 84.2719mm;

[0110] 9) The sum of the distances between the aperture C and its adjacent lenses: D = 8.5392 mm;

[0111] 10) Radius of curvature of the object side of the ninth lens L9: R 91 =610.3965mm;

[0112] 11) Radius of curvature of the image-side surface of the ninth lens L9: R 92 =14.7617mm;

[0113] 12) Abbe number of the third lens L3: V d3 =81.61;

[0114] 13) Abbe number of the fourth lens L4: V d4 =27.76.

[0115] Then we get: (f G1 ×f / f G2 )×tan(FOV / 4)=1.4120;|f u1 / f u2 |=6.0448; FOV / CRA=1.2880; D / TTL=0.1013; (R 91 -R 92 ) / (R 91 +R 92)=0.9528;|V d3 -V d4 |=53.85.

[0116] The final imaging effect of the lens in this example is achieved through Figure 8-12 To evaluate, from Figure 8 As can be seen from the figure, the MTF curves under each field of view all decrease smoothly and have good consistency. As can be seen from the figure, at the edge of the field of view at a spatial frequency of 60pl / mm, the MTF value is greater than 0.5, which means that the lens has good imaging effect and resolution in the entire field of view. Figure 9 As can be seen from the field curvature distortion diagram, the distortion of the lens does not exceed 0.35%; Figure 10 It can be seen from the relative illumination curve that at the maximum field of view, the relative illumination value of the lens is greater than 0.5; Figure 11 This is the axial aberration diagram of the lens of this embodiment. It can be seen that the maximum axial aberration does not exceed 0.03mm, and the image quality is good; Figure 12 This is the vertical axis chromatic aberration curve. It can be seen that the vertical axis chromatic aberration is less than 1.5μm.

[0117] Example 3

[0118] In the optical system of this example, the first lens L1 is a positive meniscus lens with its convex surface facing the object; the second lens L2 is a positive meniscus lens with its convex surface facing the object; the third lens L3 is a biconvex positive lens; the fourth lens L4 is a biconcave negative lens; the fifth lens L5 is a biconcave negative lens; the sixth lens L6 is a biconvex positive lens; the seventh lens L7 is a biconvex positive lens; the eighth lens L8 is a positive meniscus lens with its convex surface facing the object; and the ninth lens L9 is a biconcave negative lens. The optical path diagram of this traffic lens is shown in Figure 13 shown.

[0119] See Table 3, which lists the relevant parameters of each lens in this example, including the radius of curvature, thickness, refractive index of the material, and Abbe number:

[0120] Table 3

[0121]

[0122] Infinity means infinity.

[0123] In this example, the air distance between the first lens L1 and the second lens L2 is 11.3178 mm; the air distance between the second lens L2 and the third lens L3 is 0.1000 mm; the air distance between the fourth lens L4 and the fifth lens L5 is 5.1441 mm; the air distance between the sixth lens L6 and the aperture C is 3.1059 mm; the air distance between the aperture C and the seventh lens L7 is 4.0339 mm; the air distance between the seventh lens L7 and the eighth lens L8 is 0.1000 mm; the air distance between the eighth lens L8 and the ninth lens L9 is 0.8268 mm; and the air distance between the ninth lens L9 and the image plane IMG is 14.9262 mm.

[0124] The technical indicators achieved by the optical system in this example are as follows:

[0125] 1) Maximum field of view of traffic camera: FOV = 18.6°;

[0126] 2) Effective focal length of the first cemented lens group: f G1 =-47.7046mm;

[0127] 3) Effective focal length of the second cemented lens group: f G2 =-162.0261mm;

[0128] 4) Effective focal length of the front lens group: f u1 =204.1278mm;

[0129] 5) Effective focal length of the rear lens group: f u2 =33.1161mm;

[0130] 6) Chief ray angle of traffic lens: CRA = 14.9340°;

[0131] 7) Effective focal length of traffic lens: f = 49.9392mm;

[0132] 8) Total optical length of traffic lens: TTL = 83.5460mm;

[0133] 9) The sum of the distances between the aperture C and its adjacent lenses: D = 7.1398 mm;

[0134] 10) Radius of curvature of the object side of the ninth lens L9: R 91 =-750.0002mm;

[0135] 11) Radius of curvature of the image-side surface of the ninth lens L9: R 92 =15.3244mm;

[0136] 12) Abbe number of the third lens L3: V d3 =81.61;

[0137] 13) Abbe number of the fourth lens L4: V d4 =27.76.

[0138] Then we get: (f G1 ×f / f G2 )×tan(FOV / 4)=1.1959;|f u1 / f u2 |=6.1640; FOV / CRA=1.2455; D / TTL=0.0855; (R 91 -R 92 ) / (R 91 +R 92 )=1.0417;|V d3 -V d4 |=53.85.

[0139] The final imaging effect of the lens in this example is achieved through Figure 14-18 To evaluate, from Figure 14 As can be seen from the figure, the MTF curves under each field of view all decrease smoothly and have good consistency. As can be seen from the figure, at the edge of the field of view at a spatial frequency of 60pl / mm, the MTF value is greater than 0.65, which means that the lens has good imaging effect and resolution in the entire field of view. Figure 15 As can be seen from the field curvature distortion diagram, the distortion of the lens does not exceed 0.3%; Figure 16 It can be seen from the relative illumination curve that at the maximum field of view, the relative illumination value of the lens is greater than 0.5; Figure 17 This is the axial aberration diagram of the lens of this embodiment. It can be seen that the maximum axial aberration does not exceed 0.04mm, and the image quality is good; Figure 18 This is a vertical axis chromatic aberration curve. It can be seen that the vertical axis chromatic aberration is less than 1μm.

[0140] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A low-distortion, large-area, high-light-throughput, high-resolution intelligent traffic lens, characterized by: The optical system of the traffic lens consists of a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, an aperture C, a seventh lens L7, an eighth lens L8, a ninth lens L9 and an image plane IMG, which are arranged in sequence along the incident light path. The first lens L1 is a positive meniscus lens with its convex surface facing the object; The second lens L2 is a biconvex positive lens or a meniscus positive lens with the convex surface facing the object; The third lens L3 is a biconvex positive lens; The fourth lens L4 is a biconcave negative lens; The fifth lens L5 is a biconcave negative lens; The sixth lens L6 is a biconvex positive lens; The seventh lens L7 is a biconvex positive lens; The eighth lens L8 is a positive meniscus lens with its convex surface facing the object. The ninth lens L9 is a meniscus negative lens or a biconcave negative lens with its concave surface facing the image side; The first lens L1 to the sixth lens L6 form a front lens group; the seventh lens L7 to the ninth lens L9 form a rear lens group. The third lens L3 and the fourth lens L4 form a first cemented lens group; the fifth lens L5 and the sixth lens L6 form a second cemented lens group; The traffic lens satisfies the following condition: 1.1≤(f G1 ×f / f G2 )×tan(FOV / 4)≤1.5, where f G1 represents the effective focal length of the first cemented lens group; f G2 represents the effective focal length of the second cemented lens group; f represents the effective focal length of the traffic lens; FOV represents the maximum field of view of the traffic lens; The traffic lens also satisfies the following condition: 6.0≤|f u1 / f u2 |≤7.3, where f u1 Indicates the effective focal length of the front lens group; f u2 Indicates the effective focal length of the rear lens group; The ninth lens L9 satisfies the following conditions: 0.8≤(R 91 -R 92 ) / (R 91 +R 92 )≤1.1, where R 91 R represents the curvature radius of the object side of the ninth lens L9; 92 It represents the curvature radius of the image-side surface of the ninth lens L9.

2. The low-distortion, large-area, high-light-throughput, and high-resolution intelligent traffic lens according to claim 1, characterized in that: The traffic lens also satisfies the following conditional formula: 1.1≤FOV / CRA≤1.3, wherein FOV represents the maximum field of view angle of the traffic lens; CRA represents the main ray angle of the traffic lens.

3. The low-distortion, large-area, high-light-throughput, and high-resolution intelligent traffic lens according to claim 1, characterized in that: The traffic lens also satisfies the following conditional formula: 0.05≤D / TTL≤0.11, where D represents the sum of the distances between the aperture C and its front and rear adjacent lenses; and TTL represents the total optical length of the traffic lens.

4. The low-distortion, large-area, high-light-throughput, and high-resolution intelligent traffic lens according to claim 1, characterized in that: The traffic lens also satisfies the following condition: 53≤|V d3 -V d4 |≤54, where V d3 V represents the Abbe number of the third lens L3; d4 It represents the Abbe number of fourth lens L4.

5. The low-distortion, large-area, high-light-throughput, and high-resolution intelligent traffic lens according to claim 1, characterized in that: When the first lens L1 is a positive meniscus lens with its convex surface facing the object; the second lens L2 is a positive meniscus lens with its convex surface facing the object; the third lens L3 is a double-convex positive lens; the fourth lens L4 is a double-concave negative lens; the fifth lens L5 is a double-concave negative lens; the sixth lens L6 is a double-convex positive lens; the seventh lens L7 is a double-convex positive lens; the eighth lens L8 is a positive meniscus lens with its convex surface facing the object; and the ninth lens L9 is a negative meniscus lens with its concave surface facing the image, the air distance from the first lens L1 to the second lens L2 is 11.9695 mm; the second lens L2 to The air distance between the third lens L3 is 0.1000mm; the air distance between the fourth lens L4 and the fifth lens L5 is 5.0987mm; the air distance between the sixth lens L6 and the aperture C is 1.9249mm; the air distance between the aperture C and the seventh lens L7 is 2.5000mm; the air distance between the seventh lens L7 and the eighth lens L8 is 0.1000mm; the air distance between the eighth lens L8 and the ninth lens L9 is 0.6895mm; and the air distance between the ninth lens L9 and the image plane IMG is 17.2737mm.

6. The low-distortion, large-area, high-light-throughput, and high-resolution intelligent traffic lens according to claim 1, characterized in that: When the first lens L1 is a positive meniscus lens with its convex surface facing the object; the second lens L2 is a biconvex positive lens; the third lens L3 is a biconvex positive lens; the fourth lens L4 is a biconcave negative lens; the fifth lens L5 is a biconcave negative lens; the sixth lens L6 is a biconvex positive lens; the seventh lens L7 is a biconvex positive lens; the eighth lens L8 is a positive meniscus lens with its convex surface facing the object; and the ninth lens L9 is a negative meniscus lens with its concave surface facing the image, the air distance from the first lens L1 to the second lens L2 is 12.6475 mm; the air distance from the second lens L2 to the third lens L4 is 12.6475 mm. The air distance of the lens L3 is 0.0931mm; the air distance from the fourth lens L4 to the fifth lens L5 is 4.5468mm; the air distance from the sixth lens L6 to the aperture C is 1.7186mm; the air distance from the aperture C to the seventh lens L7 is 6.8206mm; the air distance from the seventh lens L7 to the eighth lens L8 is 0.1000mm; the air distance from the eighth lens L8 to the ninth lens L9 is 0.6965mm; and the air distance from the ninth lens L9 to the image plane IMG is 15.5862mm.

7. The low-distortion, large-area, high-light-throughput, and high-resolution intelligent traffic lens according to claim 1, characterized in that: When the first lens L1 is a positive meniscus lens with its convex surface facing the object; the second lens L2 is a positive meniscus lens with its convex surface facing the object; the third lens L3 is a double-convex positive lens; the fourth lens L4 is a double-concave negative lens; the fifth lens L5 is a double-concave negative lens; the sixth lens L6 is a double-convex positive lens; the seventh lens L7 is a double-convex positive lens; the eighth lens L8 is a positive meniscus lens with its convex surface facing the object; and the ninth lens L9 is a double-concave negative lens, the air distance from the first lens L1 to the second lens L2 is 11.3178 mm; the air distance from the second lens L2 to the third lens L3 is 11.3178 mm. The air distance between the fourth lens L4 and the fifth lens L5 is 5.1441 mm; the air distance between the sixth lens L6 and the aperture C is 3.1059 mm; the air distance between the aperture C and the seventh lens L7 is 4.0339 mm; the air distance between the seventh lens L7 and the eighth lens L8 is 0.1000 mm; the air distance between the eighth lens L8 and the ninth lens L9 is 0.8268 mm; and the air distance between the ninth lens L9 and the image plane IMG is 14.9262 mm.

Images