An industrial lens with large image surface, low distortion and low chromatic aberration

Abstract

The invention discloses an industrial lens with large target surface, low distortion and low chromatic aberration. The optical system of the industrial lens is composed of a meniscus positive lens L1, a meniscus negative lens L2, a double concave negative lens L3, a positive lens L4, an aperture C, a positive lens L5, a double convex positive lens L6, a double concave negative lens L7, a double convex positive lens L8, a double convex positive lens L9, a double concave negative lens L10, a double convex positive lens L11 and an image plane IMG, wherein the object side surface of the meniscus positive lens L1 is a convex surface; the object side surface of the meniscus negative lens L2 is a convex surface; the double convex positive lens L6 and the double concave negative lens L7 form a first cemented group; the double convex positive lens L9 and the double concave negative lens L10 form a second cemented group. The industrial lens has the performance of small volume, large target surface, low distortion, low chromatic aberration and high resolution.

Description

Technical Field

[0001] The invention belongs to the technical field of optical lenses, and in particular relates to an industrial lens with a large target surface, low distortion and low chromatic aberration. Background Art

[0002] Industrial lenses are indispensable visual components in industrial automation systems. They play a key role in fields such as machine vision, quality control, and automated manufacturing, and are responsible for capturing image data.

[0003] These lenses are equivalent to the "eyes" of the machine, and their performance directly determines the effectiveness of the entire visual system. Due to the particularity of industrial applications, industrial lenses often need to have higher standards than ordinary lenses, such as larger imaging area, lower image distortion and chromatic aberration, clearer image quality and smaller size.

[0004] Currently, industrial lenses still have certain deficiencies and defects in meeting these high standards. The market demand for small industrial lenses that can provide a larger imaging range, less distortion and chromatic aberration, and higher clarity is increasing.

[0005] Therefore, it is particularly important to invent a lens that meets the above requirements. Summary of the invention

[0006] In view of the deficiencies in the prior art, the present invention provides an industrial lens with a large target surface, low distortion and low chromatic aberration, so that it has the performance of small size, large target surface, low distortion, low chromatic aberration and high resolution.

[0007] To achieve the above object, the present invention provides the following technical solution: an industrial lens with a large target surface, low distortion and low chromatic aberration, wherein the optical system of the industrial lens is composed of a meniscus positive lens L1, a meniscus negative lens L2, a double concave negative lens L3, a positive lens L4, an aperture C, a positive lens L5, a double convex positive lens L6, a double concave negative lens L7, a double convex positive lens L8, a double convex positive lens L9, a double concave negative lens L10, a double convex positive lens L11 and an image plane IMG, wherein:

[0008] The object side surface of the positive meniscus lens L1 is convex; the object side surface of the negative meniscus lens L2 is convex;

[0009] The biconvex positive lens L6 and the biconcave negative lens L7 form a first cemented group;

[0010] The biconvex positive lens L9 and the biconcave negative lens L10 form a second cemented group;

[0011] The positive meniscus lens L1, the negative meniscus lens L2, the double concave negative lens L3 and the positive lens L4 constitute a front lens group with negative optical power;

[0012] The positive lens L5, the biconvex positive lens L6, the biconcave negative lens L7, the biconvex positive lens L8, the biconvex positive lens L9, the biconcave negative lens L10 and the biconvex positive lens L11 constitute a rear lens group with positive optical power;

[0013] The total focal length of the optical system is f, and the focal length of the first cemented group is f G1 , the focal length of the second cemented group is f G2 , satisfying the relationship: -1.4≤(f G1 ×f / f G2 )×tan(FOV / 4)≤-1.2, where FOV represents the maximum field of view of the industrial lens.

[0014] As a specific implementation, the focal length of the meniscus positive lens L1 is f u1 , the focal length of the meniscus negative lens L2 is f u2 , both satisfy the following conditions:

[0015] |f u1 / f|≤3.6;

[0016] |f u2 / f|≥2.4;

[0017] 0.3≤|f u1 / f u2 |≤1.6, where f is the total focal length of the optical system.

[0018] As a specific implementation, the maximum field of view FOV and the total optical length TTL of the industrial lens satisfy the following relationship: FOV / (D×TTL)≥0.03, wherein FOV represents the maximum field of view of the industrial lens; D represents the aperture size of the industrial lens head; TTL represents the total optical length of the industrial lens, that is, the distance from the center of the object side of the meniscus positive lens L1 to the image plane IMG.

[0019] As a specific implementation, the industrial lens satisfies the following condition: IH / FNO≥2.58, wherein IH represents the maximum image plane height of the industrial lens, and FNO represents the aperture value of the industrial lens.

[0020] As a specific implementation, the refractive index N of the positive lens L4 is d4 Meet the following conditions: N d4 ≥1.9; refractive index N of biconvex positive lens L6 d6 Meet the following conditions: N d6 ≤1.5.

[0021] As a specific implementation, the positive lens L4 uses any one of a biconvex positive lens, a plano-convex positive lens, and a meniscus positive lens; the positive lens L5 uses a meniscus positive lens or a plano-convex positive lens.

[0022] As a specific implementation, when the positive lens L4 adopts a biconvex positive lens, and the positive lens L5 adopts a meniscus positive lens with a convex object side, the air distance from the meniscus positive lens L1 to the meniscus negative lens L2 is 0.1000mm; the air distance from the meniscus negative lens L2 to the biconcave negative lens L3 is 4.0652mm; the air distance from the biconcave negative lens L3 to the biconvex positive lens L4 is 3.1968mm; the air distance from the biconvex positive lens L4 to the aperture C is 8.0983mm; the air distance from the aperture C to the meniscus ... The air distance of positive lens L5 is 0.1970mm; the air distance from meniscus positive lens L5 to biconvex positive lens L6 is 0.2603mm; the air distance from biconcave negative lens L7 to biconvex positive lens L8 is 0.4447mm; the air distance from biconvex positive lens L8 to biconvex positive lens L9 is 0.1000mm; the air distance from biconcave negative lens L10 to biconvex positive lens L11 is 4.6249mm; the air distance from biconvex positive lens L11 to image plane IMG is 8.9745mm.

[0023] As a specific implementation, when the positive lens L4 and the positive lens L5 both use a meniscus positive lens with a convex object side surface, the air distance from the meniscus positive lens L1 to the meniscus negative lens L2 is 0.100mm; the air distance from the meniscus negative lens L2 to the double concave negative lens L3 is 4.6494mm; the air distance from the double concave negative lens L3 to the meniscus positive lens L4 is 3.2592mm; the air distance from the meniscus positive lens L4 to the aperture C is 8.6524mm; the air distance from the aperture C to the meniscus positive lens The air distance of L5 is 0.1988mm; the air distance from the meniscus positive lens L5 to the biconvex positive lens L6 is 1.0249mm; the air distance from the biconcave negative lens L7 to the biconvex positive lens L8 is 0.2962mm; the air distance from the biconvex positive lens L8 to the biconvex positive lens L9 is 0.100mm; the air distance from the biconcave negative lens L10 to the biconvex positive lens L11 is 4.8231mm; the air distance from the biconvex positive lens L11 to the image plane IMG is 9.1836mm.

[0024] As a specific implementation, when the positive lens L4 and the positive lens L5 are plano-convex positive lenses, the air distance from the meniscus positive lens L1 to the meniscus negative lens L2 is 0.1000mm; the air distance from the meniscus negative lens L2 to the double concave negative lens L3 is 4.3722mm; the air distance from the double concave negative lens L3 to the plano-convex positive lens L4 is 3.1099mm; the air distance from the plano-convex positive lens L4 to the aperture C is 7.0657mm; the air distance from the aperture C to the plano-convex positive lens L5 is 1.8mm; the air distance from the double concave negative lens L3 to the plano-convex positive lens L4 is 2.6mm; the air distance from the aperture C to the plano-convex positive lens L5 is 3.1mm; the air distance from the double concave negative lens L3 to the plano-convex positive lens L4 ... The air distance is 0.2269mm; the air distance from the plano-convex positive lens L5 to the biconvex positive lens L6 is 2.3463mm; the air distance from the biconcave negative lens L7 to the biconvex positive lens L8 is 0.1504mm; the air distance from the biconvex positive lens L8 to the biconvex positive lens L9 is 0.1000mm; the air distance from the biconcave negative lens L10 to the biconvex positive lens L11 is 4.0611mm; the air distance from the biconvex positive lens L11 to the image plane IMG is 8.8137mm.

[0025] Compared with the prior art, the present invention provides an industrial lens with a large target surface, low distortion and low chromatic aberration, which has the following beneficial effects:

[0026] 1) In the present invention, the biconvex positive lens L6 and the biconcave negative lens L7 form a first cemented group, and the biconvex positive lens L9 and the biconcave negative lens L10 form a second cemented group. The lens bonding can effectively improve the chromatic aberration and distortion of the optical system and reduce the assembly sensitivity of the optical system;

[0027] 2) Control the focal length of the positive lens L4 to meet the needs of miniaturization of industrial lenses;

[0028] 3) Control the incident light to focus on a wider image plane through the aperture, thereby achieving the large target surface requirement of the lens;

[0029] 4) The lens materials used in the optical system of the present invention are all glass materials with conventional refractive index, which effectively reduces the cost;

[0030] 5) By rationally allocating the optical power of the front lens group and the rear lens group, the requirement of clear imaging of a large target surface can be achieved during the imaging process. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a schematic diagram of the optical structure of an industrial lens with a large target surface, low distortion and low chromatic aberration proposed by the present invention;

[0032] Figure 2 This is the optical path diagram of the industrial lens with large target surface, low distortion and low chromatic aberration in Example 1;

[0033] Figure 3 The MTF curve of the large-target-surface, low-distortion, and low-chromatic-aberration industrial lens in the visible light band in Example 1;

[0034] Figure 4 The field curvature and distortion diagram of the large target surface, low distortion and low chromatic aberration industrial lens in the visible light band in Example 1;

[0035] Figure 5 The vertical axis chromatic aberration curve of the industrial lens with large target surface, low distortion and low chromatic aberration in the visible light band in Example 1;

[0036] Figure 6 This is a longitudinal aberration diagram of the large target surface, low distortion and low chromatic aberration industrial lens in the visible light band in Example 1;

[0037] Figure 7 This is the optical path diagram of the industrial lens with large target surface, low distortion and low chromatic aberration in Example 2;

[0038] Figure 8 The MTF curve of the large-target-surface, low-distortion, and low-chromatic-aberration industrial lens in the visible light band in Example 2;

[0039] Fig. 9 The field curvature and distortion diagram of the large target surface, low distortion and low chromatic aberration industrial lens in the visible light band in Example 2;

[0040] Fig.10 The vertical axis chromatic aberration curve of the industrial lens with large target surface, low distortion and low chromatic aberration in the visible light band in Example 2;

[0041] Fig.11 This is a longitudinal aberration diagram of the large target surface, low distortion and low chromatic aberration industrial lens in the visible light band in Example 2;

[0042] Fig.12 This is the optical path diagram of the industrial lens with large target surface, low distortion and low chromatic aberration in Example 3;

[0043] Fig.13 The MTF curve of the large-target-surface, low-distortion, and low-chromatic-aberration industrial lens in the visible light band in Example 3;

[0044] Fig.14 The field curvature and distortion diagram of the large target surface, low distortion and low chromatic aberration industrial lens in the visible light band in Example 3;

[0045] Fig.15 The vertical axis chromatic aberration curve of the industrial lens with large target surface, low distortion and low chromatic aberration in the visible light band in Example 3;

[0046] Fig.16 This is the longitudinal aberration diagram of the industrial lens with large target surface, low distortion and low chromatic aberration in the visible light band in Example 3. DETAILED DESCRIPTION

[0047] 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 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 creative work are within the scope of protection of the present invention.

[0048] See also Figure 1 As shown, the present invention provides an industrial lens with large target surface, low distortion and low chromatic aberration, wherein the optical system of the industrial lens consists of a meniscus positive lens L1, a meniscus negative lens L2, a double concave negative lens L3, a positive lens L4, an aperture C, a positive lens L5, a double convex positive lens L6, a double concave negative lens L7, a double convex positive lens L8, a double convex positive lens L9, a double concave negative lens L10, a double convex positive lens L11 and an image plane IMG, wherein the object side surface of the meniscus positive lens L1 is a convex surface; the object side surface of the meniscus negative lens L2 is a convex surface; the double convex positive lens L6 and the double concave negative lens L7 form a first cemented group; the double convex positive lens L9 and the double concave negative lens L10 form a second cemented group; the meniscus positive lens L1, the meniscus negative lens L2, the double concave negative lens L3 and the positive lens L4 constitute a front lens group with negative optical power;

[0049] The positive lens L5, the biconvex positive lens L6, the biconcave negative lens L7, the biconvex positive lens L8, the biconvex positive lens L9, the biconcave negative lens L10 and the biconvex positive lens L11 constitute a rear lens group with positive optical power.

[0050] The lens materials in this optical system are all glass materials with regular refractive index. Example 1

[0051] In the optical system of this example, the positive lens L4 is a double convex positive lens, the positive lens L5 is a meniscus positive lens, and the object side of the positive lens L5 is a convex surface. Figure 2 shown.

[0052] 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:

[0053] Table 1

[0054]

[0055] Infinity means infinity.

[0056] In this example, the air distance from the meniscus positive lens L1 to the meniscus negative lens L2 is 0.1000mm; the air distance from the meniscus negative lens L2 to the double concave negative lens L3 is 4.0652mm; the air distance from the double concave negative lens L3 to the double convex positive lens L4 is 3.1968mm; the air distance from the double convex positive lens L4 to the aperture C is 8.0983mm; the air distance from the aperture C to the meniscus positive lens L5 is 0.1970mm; The air distance from the positive lens L5 to the biconvex positive lens L6 is 0.2603mm; the air distance from the biconcave negative lens L7 to the biconvex positive lens L8 is 0.4447mm; the air distance from the biconvex positive lens L8 to the biconvex positive lens L9 is 0.1000mm; the air distance from the biconcave negative lens L10 to the biconvex positive lens L11 is 4.6249mm; the air distance from the biconvex positive lens L11 to the image plane IMG is 8.9745mm.

[0057] The technical indicators achieved by the optical system in this example are as follows:

[0058] 1) Maximum field of view of industrial lens: FOV = 86.0000°;

[0059] 2) Focal length of the first cemented group: f G1 =-12.8225mm;

[0060] 3) Focal length of the second cemented group: f G2 =-33.3107mm;

[0061] 4) Focal length of the meniscus positive lens L1: f u1 =-6.6619mm;

[0062] 5) Focal length of the meniscus negative lens L2: f u2 =14.9788mm;

[0063] 6) Total focal length of the optical system: f = 6.1450 mm;

[0064] 7) Industrial lens head aperture size: D = 32.2439;

[0065] 8) Total optical length of industrial lens: TTL = 63.9918mm;

[0066] 9) Maximum image height of industrial lens: IH = 5.4587mm;

[0067] 10) Aperture value of industrial lens: FNO = 1.7270;

[0068] 11) Refractive index of positive lens L4: N d4 =1.9002;

[0069] 12) The refractive index of the biconvex positive lens L6: Nd6 =1.4202.

[0070] Then we get: (f G1 ×f / f G2 )×tan(FOV / 4) =-1.2652; |f u1 / f|=1.0841;|f u2 / f|=2.4376;|f u1 / f u2 |=0.4448; FOV / (D×TTL)=0.0417; IH / FNO=3.1609.

[0071] The final imaging effect of the lens in this example is achieved through Figure 3 The MTF graph of the lens shows that the MTF curves in each field of view all drop gently and have good consistency. As can be seen from the graph, the MTF value of the edge field of view at a spatial frequency of 60pl / mm is greater than 0.62, which means that the lens has good imaging effect and resolution in the entire field of view. Figure 4 It can be seen from the field curvature distortion diagram that the distortion of this lens does not exceed 6%; Figure 5 This is a diagram of the lateral chromatic aberration of the lens of this embodiment. It can be seen that the maximum lateral chromatic aberration does not exceed 5 μm, and the imaging quality is good; Figure 6 This is the longitudinal aberration curve. It can be seen that the longitudinal chromatic aberration is less than 0.06mm. Example 2

[0072] In this example, in the optical system, the positive lens L4 is a meniscus positive lens, and the object side of the positive lens L4 is a convex surface; the positive lens L5 is a meniscus positive lens, and the object side of the positive lens L5 is a convex surface. The optical path diagram of this industrial lens is shown in Figure 7 shown.

[0073] 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:

[0074] Table 2

[0075]

[0076] In addition, in this example, the air distance from the meniscus positive lens L1 to the meniscus negative lens L2 is 0.100mm; the air distance from the meniscus negative lens L2 to the double concave negative lens L3 is 4.6494mm; the air distance from the double concave negative lens L3 to the meniscus positive lens L4 is 3.2592mm; the air distance from the meniscus positive lens L4 to the aperture C is 8.6524mm; the air distance from the aperture C to the meniscus positive lens L5 is 0.1988mm; The air distance from the lunar positive lens L5 to the biconvex positive lens L6 is 1.0249mm; the air distance from the biconcave negative lens L7 to the biconvex positive lens L8 is 0.2962mm; the air distance from the biconvex positive lens L8 to the biconvex positive lens L9 is 0.100mm; the air distance from the biconcave negative lens L10 to the biconvex positive lens L11 is 4.8231mm; the air distance from the biconvex positive lens L11 to the image plane IMG is 9.1836mm.

[0077] The technical indicators achieved by the optical system in this example are as follows:

[0078] 1) Maximum field of view of industrial lens: FOV = 86.0000°;

[0079] 2) Focal length of the first cemented group: f G1 =-13.4881mm;

[0080] 3) Focal length of the second cemented group: f G2 =-33.0526mm;

[0081] 4) Focal length of the meniscus positive lens L1: f u1 =-21.4333mm;

[0082] 5) Focal length of the meniscus negative lens L2: f u2 =15.6797mm;

[0083] 6) Total focal length of the optical system: f = 6.1555 mm;

[0084] 7) Industrial lens head aperture size: D = 33.6106mm;

[0085] 8) Total optical length of industrial lens: TTL = 66.2177mm;

[0086] 9) Maximum image height of industrial lens: IH = 5.4601mm;

[0087] 10) Aperture value of industrial lens: FNO = 1.7269;

[0088] 11) Refractive index of positive lens L4: N d4 =1.9002;

[0089] 12) The refractive index of the biconvex positive lens L6: N d6 =1.4202.

[0090] Then we get: (f G1 ×f / f G2 )×tan(FOV / 4) =-1.3435; |f u1 / f|=3.4820;|f u2 / f|=2.5473;|f u1 / f u2 |=1.3669; FOV / (D×TTL)=0.0386; IH / FNO=3.1619.

[0091] The final imaging effect of the present invention is achieved by Figure 8 The MTF graph of the lens shows that the MTF curves in each field of view decrease smoothly and have good consistency, which means that the lens has good imaging effect and resolution in the full field of view.

[0092] The final imaging effect of the lens in this example is achieved through Figure 8-11 To evaluate, from Figure 8 It can be seen that the MTF value of the edge field of view is greater than 0.65 at the spatial frequency of 60pl / mm; Fig. 9 From the field curvature distortion diagram in the figure, it can be seen that the distortion does not exceed 6%; Fig.10 It can be seen from the lateral chromatic aberration diagram that the maximum lateral chromatic aberration does not exceed 5μm; Fig.11 It can be seen from the longitudinal aberration curve that the longitudinal chromatic aberration is less than 0.06mm. Example 3

[0093] In this example, the positive lens L4 is a plano-convex positive lens, and the positive lens L5 is a plano-convex positive lens. Fig.12 shown.

[0094] 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:

[0095] Table 3

[0096]

[0097] In addition, in this example, the air distance from the meniscus positive lens L1 to the meniscus negative lens L2 is 0.1000mm; the air distance from the meniscus negative lens L2 to the double concave negative lens L3 is 4.3722mm; the air distance from the double concave negative lens L3 to the plano-convex positive lens L4 is 3.1099mm; the air distance from the plano-convex positive lens L4 to the aperture C is 7.0657mm; the air distance from the aperture C to the plano-convex positive lens L5 is 0.2269mm; The air distance from the convex positive lens L5 to the biconvex positive lens L6 is 2.3463mm; the air distance from the biconcave negative lens L7 to the biconvex positive lens L8 is 0.1504mm; the air distance from the biconvex positive lens L8 to the biconvex positive lens L9 is 0.1000mm; the air distance from the biconcave negative lens L10 to the biconvex positive lens L11 is 4.0611mm; the air distance from the biconvex positive lens L11 to the image plane IMG is 8.8137mm.

[0098] The technical indicators achieved by the optical system in this example are as follows:

[0099] 1) Maximum field of view of industrial lens: FOV = 86°;

[0100] 2) Focal length of the first cemented group: f G1 =-12.7104;

[0101] 3) Focal length of the second cemented group: f G2 =-33.1598;

[0102] 4) Focal length of the meniscus positive lens L1: f u1 =-16.9510;

[0103] 5) Focal length of the meniscus negative lens L2: f u2 =15.5009;

[0104] 6) Total focal length of the optical system: f = 6.1104;

[0105] 7) Industrial lens head aperture size: D = 34.2966;

[0106] 8) Total optical length of industrial lens: TTL=64.2763;

[0107] 9) Maximum image height of industrial lens: IH=4.4603;

[0108] 10) Aperture value of industrial lens: FNO = 1.7288;

[0109] 11) Refractive index of positive lens L4: N d4 =1.9002;

[0110] 12) The refractive index of the biconvex positive lens L6: N d6=1.4202.

[0111] Then we get: (f G1 ×f / f G2 )×tan(FOV / 4) =-1.2527; |f u1 / f|=2.7741;|f u2 / f|=2.5368;|f u1 / f u2 |=1.0935; FOV / (D×TTL)=0.0390; IH / FNO=2.5800.

[0112] The final imaging effect of the lens in this example is achieved through Figure 13-16 To evaluate, from Fig.13 It can be seen that the MTF value of the edge field at the spatial frequency of 60pl / mm is greater than 0.55; Fig.14 From the field curvature distortion diagram in the figure, it can be seen that the distortion does not exceed 4.5%; Fig.15 It can be seen from the lateral chromatic aberration diagram that the maximum lateral chromatic aberration does not exceed 5μm; Fig.16 It can be seen from the longitudinal aberration curve that the longitudinal chromatic aberration is less than 0.055mm.

[0113] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An industrial lens with large target surface, low distortion and low chromatic aberration, characterized in that: The optical system of the industrial lens is composed of a meniscus positive lens L1, a meniscus negative lens L2, a double concave negative lens L3, a positive lens L4, an aperture C, a positive lens L5, a double convex positive lens L6, a double concave negative lens L7, a double convex positive lens L8, a double convex positive lens L9, a double concave negative lens L10, a double convex positive lens L11 and an image plane IMG, which are arranged in sequence along the incident light path. The object side surface of the positive meniscus lens L1 is convex; the object side surface of the negative meniscus lens L2 is convex; The biconvex positive lens L6 and the biconcave negative lens L7 form a first cemented group; The biconvex positive lens L9 and the biconcave negative lens L10 form a second cemented group; The positive meniscus lens L1, the negative meniscus lens L2, the double concave negative lens L3 and the positive lens L4 constitute a front lens group with negative optical power; The positive lens L5, the biconvex positive lens L6, the biconcave negative lens L7, the biconvex positive lens L8, the biconvex positive lens L9, the biconcave negative lens L10 and the biconvex positive lens L11 constitute a rear lens group with positive optical power; The focal length of the meniscus positive lens L1 is f u1 , the focal length of the meniscus negative lens L2 is f u2 , both satisfy the following conditions: |f u1 / f|≤3.6; 2.4≤|f u2 / f|≤2.5473; 0.3≤|f u1 / f u2 |≤1.6, where f is the total focal length of the optical system; The maximum field of view FOV and the total optical length TTL of the industrial lens satisfy the following relationship: 0.03≤FOV / (D×TTL)≤0.0417, wherein FOV represents the maximum field of view of the industrial lens; D represents the aperture size of the industrial lens head; TTL represents the total optical length of the industrial lens, that is, the distance from the center of the object side of the meniscus positive lens L1 to the image plane IMG.

2. The industrial lens with large target surface, low distortion and low chromatic aberration according to claim 1, characterized in that: The industrial lens satisfies the following condition: 2.58≤IH / FNO≤3.1619, wherein IH represents the maximum image plane height of the industrial lens, and FNO represents the aperture value of the industrial lens.

3. The industrial lens with large target surface, low distortion and low chromatic aberration according to claim 1, characterized in that: Refractive index N of positive lens L4 d4 Meet the following conditions: N d4 ≥1.9; refractive index N of biconvex positive lens L6 d6 Meet the following conditions: N d6 ≤1.

5.

4. The industrial lens with large target surface, low distortion and low chromatic aberration according to claim 1, characterized in that: The positive lens L4 adopts any one of a double convex positive lens, a plano-convex positive lens, and a meniscus positive lens; the positive lens L5 adopts a meniscus positive lens or a plano-convex positive lens.

5. The industrial lens with large target surface, low distortion and low chromatic aberration according to claim 4, characterized in that: When the positive lens L4 adopts a double convex positive lens, and the positive lens L5 adopts a meniscus positive lens with a concave object side, the air distance from the meniscus positive lens L1 to the meniscus negative lens L2 is 0.1000mm; the air distance from the meniscus negative lens L2 to the double concave negative lens L3 is 4.0652mm; the air distance from the double concave negative lens L3 to the double convex positive lens L4 is 3.1968mm; the air distance from the double convex positive lens L4 to the aperture C is 8.0983mm; the air distance from the aperture C to the meniscus positive lens L5 is 1.86mm. The air distance is 0.1970mm; the air distance from the meniscus positive lens L5 to the biconvex positive lens L6 is 0.2603mm; the air distance from the biconcave negative lens L7 to the biconvex positive lens L8 is 0.4447mm; the air distance from the biconvex positive lens L8 to the biconvex positive lens L9 is 0.1000mm; the air distance from the biconcave negative lens L10 to the biconvex positive lens L11 is 4.6249mm; the air distance from the biconvex positive lens L11 to the image plane IMG is 8.9745mm.

6. The industrial lens with large target surface, low distortion and low chromatic aberration according to claim 4, characterized in that: When both positive lens L4 and positive lens L5 use a meniscus positive lens with a concave object side surface, the air distance from the meniscus positive lens L1 to the meniscus negative lens L2 is 0.100mm; the air distance from the meniscus negative lens L2 to the double concave negative lens L3 is 4.6494mm; the air distance from the double concave negative lens L3 to the meniscus positive lens L4 is 3.2592mm; the air distance from the meniscus positive lens L4 to the aperture C is 8.6524mm; the air distance from the aperture C to the meniscus positive lens L5 is 1.86mm. The air distance from the meniscus positive lens L5 to the biconvex positive lens L6 is 0.1988mm; the air distance from the biconcave negative lens L7 to the biconvex positive lens L8 is 0.2962mm; the air distance from the biconvex positive lens L8 to the biconvex positive lens L9 is 0.100mm; the air distance from the biconcave negative lens L10 to the biconvex positive lens L11 is 4.8231mm; the air distance from the biconvex positive lens L11 to the image plane IMG is 9.1836mm.

7. The industrial lens with large target surface, low distortion and low chromatic aberration according to claim 4, characterized in that: When positive lens L4 and positive lens L5 adopt plano-convex positive lenses, the air distance from meniscus positive lens L1 to meniscus negative lens L2 is 0.1000mm; the air distance from meniscus negative lens L2 to double concave negative lens L3 is 4.3722mm; the air distance from double concave negative lens L3 to plano-convex positive lens L4 is 3.1099mm; the air distance from plano-convex positive lens L4 to aperture C is 7.0657mm; the air distance from aperture C to plano-convex positive lens L5 is 0. 2269mm; the air distance from the plano-convex positive lens L5 to the biconvex positive lens L6 is 2.3463mm; the air distance from the biconcave negative lens L7 to the biconvex positive lens L8 is 0.1504mm; the air distance from the biconvex positive lens L8 to the biconvex positive lens L9 is 0.1000mm; the air distance from the biconcave negative lens L10 to the biconvex positive lens L11 is 4.0611mm; the air distance from the biconvex positive lens L11 to the image plane IMG is 8.8137mm.

Images