A high-resolution high-uniformity large-target-surface line-scan lens

Abstract

The application discloses a high-resolution high-uniformity large-target-surface line scanning lens, which comprises a shell, a first optical system and a second optical system are arranged in the shell, and a first double-cemented lens A, a first double-cemented lens B, a first variable diaphragm S, a first double-cemented lens C, a meniscus negative lens D, a first double-cemented lens E, a meniscus positive lens F and a first image plane I are sequentially arranged in the shell, when the entire field of view WF# is 5.6, the central MTF is greater than 0.5@60 LP / MM, the edge MTF is greater than 0.5@50 LP / MM, the MTF change is uniform, the maximum change should not exceed 25 LP / MM visible light, when the entire field of view WF# is 5.6, the central MTF is greater than 0.5@40 LP / MM, and the edge MTF is greater than 0.5@30 LP / MM, so that the resolution uniformity of the lens is poor, the edge illumination is low, and the near-infrared performance is insufficient, and the lens meets most application scenarios in the market.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of lenses, in particular to a high-resolution and high-uniformity large target surface line scanning lens. BACKGROUND

[0002] The large target surface line scanning lens is a device for high-precision imaging, commonly used in industrial detection or high-resolution scanning. It captures images by performing line scanning on a large target surface, suitable for scenarios requiring large-scale and high-resolution imaging. Its working principle is to decompose the image into multiple line scans, each line is scanned one by one, and finally the complete image is synthesized. This technology can achieve detailed imaging on a large area target, suitable for application scenarios that require accurate measurement and analysis.

[0003] At present, there are few large target surface line scanning lenses that match 16K, 3.5μm cameras on the market. Even if there are, they have various defects and cannot meet the needs of most markets, which are limited. The relative illumination of the same type of lens on the market is relatively low, about 50% or so. Market feedback shows that the uniformity is poor, the edge illumination is low, and the near-infrared performance cannot meet the special application needs of some customers. SUMMARY

[0004] The purpose of the present application is to provide a high-resolution and high-uniformity large target surface line scanning lens to solve the above technical problems.

[0005] To solve the above technical problems, the present application adopts the following technical solutions:

[0006] A high-resolution and high-uniformity large target surface line scanning lens, comprising a shell, the shell is internally provided with a first optical system and a second optical system.

[0007] Preferably, the first optical system comprises a first double cemented lens A, which is fixedly connected with the shell;

[0008] The right side of the first double cemented lens A is provided with a first double cemented lens B, which is fixedly connected with the shell;

[0009] The right side of the first double cemented lens B is provided with a first variable diaphragm S, which is fixedly connected with the shell;

[0010] The right side of the first variable diaphragm S is provided with a first double cemented lens C, which is fixedly connected with the shell;

[0011] The right side of the first double cemented lens C is provided with a meniscus negative lens D, which is fixedly connected with the shell;

[0012] The meniscus negative lens D is provided with a first doublet lens E on the right side, and the first doublet lens E is fixedly connected with the shell;

[0013] The meniscus positive lens F is provided on the right side of the first doublet lens E, and the meniscus positive lens F is fixedly connected with the shell.

[0014] Preferably, the air gap between the first doublet lens A and the first doublet lens B is 7.6560mm;

[0015] The air gap between the first doublet lens B and the first variable diaphragm S is 2.14150mm;

[0016] The air gap between the first variable diaphragm S and the first doublet lens C is 1.63mm;

[0017] The air gap between the first doublet lens C and the meniscus negative lens D is 8.528mm;

[0018] The air gap between the meniscus negative lens D and the first doublet lens E is 0.097mm;

[0019] The air gap between the first doublet lens E and the meniscus positive lens F is 0.1mm.

[0020] Preferably, the second optical system comprises a meniscus negative lens A, which is located inside the shell and fixedly connected with the shell;

[0021] The meniscus negative lens A is provided with a second doublet lens B on the right side, and the second doublet lens B is fixedly connected with the shell;

[0022] The second doublet lens B is provided with a second doublet lens C on the right side, and the second doublet lens C is fixedly connected with the shell;

[0023] The second doublet lens C is provided with a second variable diaphragm S on the right side, and the second variable diaphragm S is fixedly connected with the shell;

[0024] The second variable diaphragm S is provided with a doublet lens D on the right side, and the doublet lens D is fixedly connected with the shell;

[0025] The doublet lens D is provided with a doublet lens E on the right side, and the doublet lens E is fixedly connected with the shell;

[0026] The doublet lens E is provided with a meniscus negative lens F on the right side, and the meniscus negative lens F is fixedly connected with the shell;

[0027] The meniscus negative lens F is provided with a meniscus positive lens G on the right side, and the meniscus positive lens G is fixedly connected with the shell.

[0028] Preferably, the air gap between the meniscus negative lens A and the second doublet lens B is 5.54mm;

[0029] The air gap between the second doublet lens B and the second doublet lens C is 6.8mm;

[0030] The air gap between the second doublet lens C and the second variable aperture S is 4.2mm;

[0031] The air gap between the second variable aperture S and the doublet lens D is 7.88mm;

[0032] The air gap between the doublet lens D and the doublet lens E is 0.1mm;

[0033] The air gap between the doublet lens E and the meniscus negative lens F is 17.7mm;

[0034] The air gap between the meniscus negative lens F and the meniscus positive lens G is 0.10mm.

[0035] The beneficial effects of the present application: the high resolution high uniformity of the large target surface line scanning lens of the application, including the shell, and sequentially setting the first doublet lens A, the first doublet lens B, the first variable aperture S, the first doublet lens C, the meniscus negative lens D, the first doublet lens E, the meniscus positive lens F, and the first image plane I, when the entire field range WF# is 5.6, the center MTF is greater than 0.5@60LP / MM, the edge MTF is greater than 0.5@50LP / MM, the MTF change is uniform, and the maximum change should not exceed 25LP / MM visible light, when the entire field range WF# is 5.6, the center MTF is greater than 0.5@40LP / MM, and the edge MTF is greater than 0.5@30LP / MM, so that the resolution uniformity of the lens is poor, the edge illumination is low, and the near-infrared performance is insufficient, and the lens meets most of the application scenarios in the market. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 It is the optical system diagram of the embodiment 1 of the present application;

[0037] Figure 2 It is the modulation transfer function diagram of the visible light of the embodiment 1 of the present application under 60lp / mm;

[0038] Figure 3 It is the modulation transfer function diagram of the near-infrared of the embodiment 1 of the present application under 60lp / mm;

[0039] Figure 4 It is the distortion diagram of the embodiment 1 of the present application;

[0040] Figure 5 It is the relative illumination diagram of the embodiment 1 of the present application;

[0041] Figure 6 Optical system diagram of embodiment 2 of the present application;

[0042] Figure 7 Modulation transfer function diagram of visible light at 60 lp / mm of embodiment 2 of the present application;

[0043] Figure 8 Modulation transfer function diagram of near infrared at 60 lp / mm of embodiment 2 of the present application;

[0044] Figure 9 Distortion diagram of embodiment 2 of the present application;

[0045] Figure 10 Relative luminance diagram of embodiment 2 of the present application.

[0046] Reference numerals: 1, first doublet lens A; 2, first doublet lens B; 3, first variable diaphragm S; 4, first doublet lens C; 5, meniscus negative lens D; 6, first doublet lens E; 7, meniscus positive lens F; 8, first image plane I; 9, meniscus negative lens A,; 10, second doublet lens B; 11, second doublet lens C; 12, second variable diaphragm S; 13, doublet lens D; 14, second doublet lens E; 15, meniscus negative lens F; 16, meniscus positive lens G; 17, second image plane I. DETAILED DESCRIPTION

[0047] In order to make the technical means, creative features, purposes and effects realized by the present application easy to understand, the following further describes the present application in combination with specific embodiments and drawings. However, the following embodiments are only preferred embodiments of the present application, and are not all. Based on the embodiments in the embodiments, other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the present application.

[0048] The specific embodiments of the present application are described below in combination with the drawings.

[0049] Embodiment 1:

[0050] As shown in Figures 1-5

[0051] The present application meets the following technical indicators:

[0052] Focal length: 35 mm;

[0053] Aperture: 4;

[0054] Wavelength: visible light & near infrared (0.45 um-0.98 um);

[0055] Imaging circle: 57.5 mm;

[0056] ​Distortion: less than 2%;

[0057] Relative illumination: greater than 60%;

[0058] Conjugate distance: less than 1200mm;

[0059] Image quality requirements: ① Throughout the field of view, when WF# = 5.6, the center MTF > 0.5@60LP / MM, the edge MTF > 0.5@50LP / MM, the MTF change is uniform, and the maximum change should not exceed 25LP / MM (for example, the maximum is 65LP / MM, and the minimum is 50LP / MM) --- visible light

[0060] ② Throughout the field of view, when WF# = 5.6, the center MTF > 0.5@40LP / MM, and the edge MTF > 0.5@30LP / MM.

[0061] The line scanning imaging system of the application is composed of 6 groups of 10 lenses, 4 of which are glued lenses and two are single lenses.

[0062] The length of the entire lens satisfies the following conditions:

[0063] TTHI≤155mm

[0064] Where TTHI represents the total optical length, that is, the distance from the first surface of the first double-glued lens A1 to the imaging surface.

[0065] Further, the combined system of the first double-glued lens A1 and the first double-glued lens B2 satisfies the following conditions:

[0066] |Φ AB |≤0.015mm -1

[0067] Where Φ AB represents the combined focal power of the first double-glued lens A1 and the first double-glued lens B2.

[0068] Further, the first double-glued lens C4 satisfies the following conditions:

[0069] n C1 ≥1.55

[0070] v C2 ≤80.0

[0071] Where n C1 represents the refractive index of the C1 lens material, and v C2 represents the Abbe number of the C2 lens material.

[0072] Further, the meniscus negative lens D satisfies the following conditions:

[0073] nD ≥ 1.45

[0074] v D ≥ 65.0

[0075] wherein n D represents the refractive index of the meniscus negative lens D, v D represents the dispersion coefficient of the meniscus negative lens D.

[0076] Further, the first doublet lens E satisfies the following condition:

[0077] -10mm ≤ f E ≤ 100mm

[0078] wherein f E represents the focal length of the first doublet lens E.

[0079] Further, the meniscus positive lens F satisfies the following condition:

[0080]

[0081] wherein f f represents the optical focal length of the meniscus positive lens F, d f represents the clear aperture of the meniscus positive lens F.

[0082] As Figure 1 shown in the figure is an optical system of an embodiment of the present application.

[0083] A large target surface line scanning lens with high resolution and high uniformity comprises a shell, a first optical system and a second optical system are arranged in the shell.

[0084] The first optical system comprises a first doublet lens A1, and the first doublet lens A1 is fixedly connected with the shell.

[0085] The first doublet lens A1 is provided with a first doublet lens B2 on the right side, and the first doublet lens B2 is fixedly connected with the shell.

[0086] The first doublet lens B2 is provided with a first variable diaphragm S3 on the right side, and the first variable diaphragm S3 is fixedly connected with the shell.

[0087] The first variable diaphragm S3 is provided with a first doublet lens C4 on the right side, and the first doublet lens C4 is fixedly connected with the shell.

[0088] The first doublet lens C4 is provided with a meniscus negative lens D5 on the right side, and the meniscus negative lens D5 is fixedly connected with the shell.

[0089] The meniscus negative lens D5 is provided with a first doublet lens E6 on the right side, and the first doublet lens E6 is fixedly connected with the shell.

[0090] The first doublet lens E6 is provided with a meniscus positive lens F7 on the right side, and the meniscus positive lens F7 is fixedly connected with the shell.

[0091] The air interval of the first doublet lens A1 and the first doublet lens B2 is 7.6560mm;

[0092] The air interval of the first doublet lens B2 and the first variable diaphragm S3 is 2.14150mm;

[0093] The air interval of the first variable diaphragm S3 and the first doublet lens C4 is 1.63mm;

[0094] The air interval of the first doublet lens C4 and the meniscus negative lens D5 is 8.528mm;

[0095] The air interval of the meniscus negative lens D5 and the first doublet lens E6 is 0.097mm;

[0096] The air interval of the first doublet lens E6 and the meniscus positive lens F7 is 0.1mm.

[0097] The whole system focuses light to the first image plane I8, and the total length of the optical system in the embodiment is less than 100mm.

[0098] In the application, the main function of the first doublet lens A1 and the first doublet lens B2 is to reduce spherical aberration. In order to reduce distortion, the combined light path is arranged as symmetrically as possible about the diaphragm. In the embodiment, the combined focal length of the first doublet lens A1 and the first doublet lens B2 is fab=72.9466mm.

[0099] The main function of the first doublet lens C4 is to correct astigmatism, and the focal length is fc=-142.057mm. The smaller the absolute value of fab / fc is, the greater the astigmatism generated is. In the embodiment,

[0100]

[0101] The main function of the meniscus negative lens D5 and the first doublet lens E6 is to correct field curvature. In order to achieve the best correction effect and at the same time introduce as few other aberrations as possible, especially chromatic aberration, the meniscus negative lens D5 needs to have a negative focal length and a low dispersion coefficient and a low refractive index. The first doublet lens E6 needs a large focal length value. In the embodiment,

[0102] n d <1.5274900

[0103] v d >68.44048

[0104] f d <-42.61mm

[0105] f e -456.4444mm

[0106] Meniscus positive lens F7 mainly converges light rays, in order to reduce aberration, a high refractive material needs to be used, in the embodiment, the material is F2,

[0107] n f >1.8941

[0108] The specific parameters of each lens of the embodiment are shown in the table:

[0109]

[0110]

[0111] According to the above lens parameters, the related optical parameters can be calculated by using ray tracing software.

[0112] Embodiment 2:

[0113] As shown in the table, in the case that other parts are the same as embodiment 1, the difference between the embodiment and embodiment 1 is that: Figures 6-10 The line scanning imaging system of the application is composed of 7 groups of 11 lenses. 4 lenses are glued and 3 lenses are single.

[0114] The length of the entire lens satisfies the following conditions:

[0115] TTHI≤155mm

[0116] Wherein TTHI represents the total optical length, that is, the distance from the first surface of meniscus negative lens A9 to the imaging surface.

[0117] Further, the combination system of meniscus negative lens A9 and second double glued lens B10 satisfies the following conditions:

[0118] |Φ AB |≤0.005mm -1

[0119] Wherein Φ AB represents the combined focal power of meniscus negative lens A9 and second double glued lens B10. Further, the second double glued lens C11 satisfies the following conditions:

[0120] 50mm≤f c ≤100mm

[0121] Wherein f C represents the optical focal length of the second double glued lens C11.

[0122]

[0123] ​Further, the doublet lens D13 satisfies the following conditions:

[0124] n D1 ≥1.55

[0125] 55≤v D2 ≤65.0

[0126] wherein n D1 represents the refractive index of the lens material of D1, v D2 represents the Abbe number of the lens material of D2.

[0127] Further, the doublet lens E14 satisfies the following conditions:

[0128] n E1 ≥1.55

[0129] 1.73≥n E2 ≥1.69

[0130] 30≥v E2 ≥25.0

[0131] wherein n E1 represents the refractive index of the lens E1, v E2 represents the Abbe number of the lens E2.

[0132] Further, the meniscus negative lens F15 satisfies the following conditions:

[0133] -200mm≤f F ≤-30mm

[0134] v F ≥55.0

[0135] wherein f F represents the focal length of the meniscus negative lens F15, v F represents the Abbe number of the meniscus negative lens F15.

[0136] Further, the combination system of the meniscus negative lens F15 and the meniscus positive lens G16 satisfies the following conditions:

[0137] 、Φ FG |≤0.01mm -1

[0138] wherein Φ FG represents the optical power of the FG combination lens system.

[0139] As Figure 5 shown in the figure is an optical system of an embodiment of the application.

[0140] The second optical system comprises a meniscus negative lens A, which is located inside the shell and fixedly connected with the shell;

[0141] The meniscus negative lens A is provided with a second doublet B10 on the right side, and the second doublet B10 is fixedly connected with the shell;

[0142] The second doublet B10 is provided with a second doublet C11 on the right side, and the second doublet C11 is fixedly connected with the shell;

[0143] The second doublet C11 is provided with a second variable diaphragm S12 on the right side, and the second variable diaphragm S12 is fixedly connected with the shell;

[0144] The second variable diaphragm S12 is provided with a doublet D13 on the right side, and the doublet D13 is fixedly connected with the shell;

[0145] The doublet D13 is provided with a doublet E on the right side, and the doublet E is fixedly connected with the shell;

[0146] The doublet E is provided with a meniscus negative lens F15 on the right side, and the meniscus negative lens F15 is fixedly connected with the shell;

[0147] The meniscus negative lens F15 is provided with a meniscus positive lens G16 on the right side, and the meniscus positive lens G is fixedly connected with the shell.

[0148] The air interval between the meniscus negative lens A and the second doublet B10 is 5.54mm;

[0149] The air interval between the second doublet B10 and the second doublet C11 is 6.8mm;

[0150] The air interval between the second doublet C11 and the second variable diaphragm S12 is 4.2mm;

[0151] The air interval between the second variable diaphragm S12 and the doublet D13 is 7.88mm;

[0152] The interval between the doublet D13 and the doublet E is 0.1mm;

[0153] The air interval between the doublet E and the meniscus negative lens F15 is 17.7mm;

[0154] The air interval between the meniscus negative lens F15 and the meniscus positive lens G16 is 0.10mm

[0155] The meniscus positive lens G16 focuses the light rays of the whole system to the image plane I, and the air distance from the meniscus positive lens G16 to the image plane I is 29.00mm. The total length of the optical system of the embodiment is less than 150mm.

[0156] In the present invention, the main function of meniscus negative lens A9 and second doublet lens B10 is to introduce positive spherical aberration. In order to reduce the system length, the combined power needs to be small. In the present embodiment

[0157] n A ≥1.58

[0158] v A <51.51

[0159] The main function of second doublet lens C11 is to correct the field aberration. In the present embodiment,

[0160] n C1 ≤1.6

[0161] n C2 ≥1.82

[0162] The main function of doublet lens D13 and second doublet lens E14 is to correct chromatic aberration, so the lens D2 and E1 need to be made of low dispersion material with large dispersion coefficient (the larger the dispersion coefficient, the weaker the dispersion ability). In the present embodiment,

[0163] n D2 ≥1.45

[0164] 95≥v E1 ≥55.0

[0165] The main function of meniscus negative lens F15 and meniscus positive lens G16 is to correct field curvature. In order to achieve the best correction effect while introducing as little other aberration as possible, especially chromatic aberration, the F lens needs to be made of low refractive index and low dispersion coefficient, and the meniscus positive lens G16 needs to have positive focal length and high dispersion coefficient.

[0166] In the present embodiment,

[0167] n F <1.55

[0168] f G <80.95mm

[0169] n G ≥1.80

[0170] v G <31.51

[0171] As a field lens system, the combined lens of meniscus negative lens F15 and meniscus positive lens G16 needs to have as small optical power as possible.

[0172] The specific parameters of each lens in the present embodiment are shown in the table:

[0173]

[0174] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited to the above-mentioned embodiments, and the above-mentioned embodiments and descriptions in the specification are only preferred examples of the present application and are not intended to limit the present application. Various changes and improvements can be made to the present application without departing from the spirit and scope of the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A high resolution, high uniformity, large target format line scan lens comprising a housing, characterized by: The shell is internally provided with a first optical system and a second optical system; The first optical system comprises a first doublet lens A (1); The first doublet lens A (1) is provided with a first doublet lens B (2) on the right side; The first doublet lens B (2) is provided with a first variable diaphragm S (3) on the right side; The first variable diaphragm S (3) is provided with a first doublet lens C (4) on the right side; The first doublet lens C (4) is provided with a meniscus negative lens D (5) on the right side; The meniscus negative lens D (5) is provided with a first doublet lens E (6) on the right side; The first doublet lens E (6) is provided with a meniscus positive lens F (7) on the right side; The air gap between the first doublet lens A (1) and the first doublet lens B (2) is 7.6560mm; The air gap between the first doublet lens B (2) and the first variable diaphragm S (3) is 2.14150mm; The air gap between the first variable diaphragm S (3) and the first doublet lens C (4) is 1.63mm; The air gap between the first doublet lens C (4) and the meniscus negative lens D (5) is 8.528mm; The air gap between the meniscus negative lens D (5) and the first doublet lens E (6) is 0.097mm; The air gap between the first doublet lens E (6) and the meniscus positive lens F (7) is 0.1mm; The second optical system comprises a meniscus negative lens A; The meniscus negative lens A is provided with a second doublet lens B (10) on the right side; The second doublet lens B (10) is provided with a second doublet lens C (11) on the right side; The second doublet lens C (11) is provided with a second variable diaphragm S (12) on the right side; The second variable diaphragm S (12) is provided with a doublet lens D (13) on the right side; The doublet lens D (13) is provided with a doublet lens E on the right side; The doublet lens E is provided with a meniscus negative lens F (15) on the right side; The meniscus negative lens F (15) is provided with a meniscus positive lens G (16) on the right side.

2. The high resolution, high uniformity, large target format, line scan lens of claim 1, wherein: The first doublet lens A (1) is fixedly connected with the shell; The first doublet lens B (2) is fixedly connected with the shell; The first variable diaphragm S (3) is fixedly connected with the shell; The first doublet lens C (4) is fixedly connected with the shell; The meniscus negative lens D (5) is fixedly connected with the shell; The first doublet lens E (6) is fixedly connected with the shell; The meniscus positive lens F (7) is fixedly connected with the shell.

3. The high resolution, high uniformity, large target format, line scan lens of claim 1, wherein: The meniscus negative lens A is located inside the shell and is fixedly connected with the shell; The second doublet lens B (10) is fixedly connected with the shell; The second doublet lens C (11) is fixedly connected with the shell; The second variable diaphragm S (12) is fixedly connected with the shell; The doublet lens D (13) is fixedly connected with the shell; The doublet lens E is fixedly connected with the shell; The meniscus negative lens F (15) is fixedly connected with the shell; The meniscus positive lens G is fixedly connected with the shell.

4. The high resolution, high uniformity, large target format, line scan lens of claim 1, wherein: The air gap between the meniscus negative lens A and the second doublet lens B (10) is 5.54mm; The air separation between the second doublet lens B (10) and the second doublet lens C (11) is 6.8 mm; The air separation between the second doublet lens C (11) and the second variable diaphragm S (12) is 4.2 mm; The air separation between the second variable diaphragm S (12) and the doublet lens D (13) is 7.88 mm; The separation between the doublet lens D (13) and the doublet lens E is 0.1 mm; The air separation between the doublet lens E and the meniscus negative lens F (15) is 17.7 mm; The air separation between the meniscus negative lens F (15) and the meniscus positive lens G (16) is 0.10 mm.

Images