Wide-angle low-distortion lens for near infrared
The near-infrared wide-angle low-distortion lens, optimized with a specific lens combination, solves the problem that existing imaging systems struggle to achieve large image size and low distortion, thus achieving high-performance near-infrared imaging.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- 福建至期光子科技有限公司
- Filing Date
- 2026-03-19
- Publication Date
- 2026-05-15
AI Technical Summary
Existing technologies make it difficult to design high-performance near-infrared imaging systems, especially systems that simultaneously achieve large image size and low distortion. Furthermore, the processing and assembly of aspherical lenses are complex, resulting in high costs and low production yields.
Design a wide-angle, low-distortion lens for near-infrared applications, employing a specific lens combination, including a meniscus negative lens, a biconvex positive lens, and a crescent positive lens, to satisfy specific focal length and combined focal length relationships, and optimize the optical design to correct aberrations and distortions.
It achieves the wide-angle and low-distortion characteristics of a near-infrared lens, with imaging capability of wavelengths from 980nm to 1070nm, a field of view greater than ±51°, distortion less than 3.5%, numerical aperture F/2.0, image resolution of 30lp/mm>0.4, and principal ray angle less than 10°.
Smart Images
Figure CN122043711A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of lens technology, and in particular to a near-infrared lens. Background Technology
[0002] Near-infrared lasers, such as those at 980nm, 1030nm, and 1064nm, are widely used in precision machining processes in the semiconductor industry. However, high-performance imaging systems to match these lasers are relatively scarce, especially those that simultaneously demand large image size and low distortion. The design of such systems is fundamentally challenged by the interdependent optical parameters of wide field of view and low optical distortion, making their implementation extremely difficult.
[0003] Typically, aspherical lenses are considered in optical design to correct aberrations and control distortion. However, this brings new challenges in actual engineering: on the one hand, the processing and inspection of aspherical lenses are complex in order to accurately control their surface accuracy, leading to a significant increase in manufacturing costs; on the other hand, the multi-degree-of-freedom alignment tolerances of aspherical lenses are extremely stringent during system assembly, making the assembly and adjustment process complex and time-consuming, ultimately resulting in low production yield and high overall system cost. Summary of the Invention
[0004] To address the aforementioned problems, this invention proposes a wide-angle, low-distortion lens for near-infrared applications, specifically a global near-infrared lens that features both wide-angle and low-distortion characteristics.
[0005] The specific technical solution of the present invention is as follows: A wide-angle low-distortion lens for near-infrared applications comprises, from the object plane to the image plane, a coaxial meniscus negative lens A, a meniscus negative lens B, a meniscus negative lens C, a biconvex positive lens D, a biconvex positive lens E, a crescent positive lens F, a variable aperture S, a meniscus negative lens G, a crescent positive lens H, a meniscus negative lens I, a biconvex positive lens J, and a crescent positive lens K.
[0006] Furthermore, the total focal length f and total length L of the wide-angle low-distortion lens satisfy the condition: f / L≥0.085.
[0007] Furthermore, the combined focal length f of the three lenses—meniscus negative lens A, meniscus negative lens B, and meniscus negative lens C—is... ABC The total focal length f of the wide-angle low-distortion lens satisfies the condition: 2.0 ≥ |f ABC / f│≥1.5.
[0008] Furthermore, the combined focal length f of the two biconvex positive lenses D and E is... DE The total focal length f of the wide-angle low-distortion lens satisfies the condition: 3.0 ≥ |f DE / f│≥2.0.
[0009] Furthermore, the focal length f of the crescent-shaped positive lens F F The total focal length f of the wide-angle low-distortion lens satisfies the condition: |f F / f│≥10.0.
[0010] Furthermore, the combined focal length f of the meniscus negative lens G and the crescent positive lens H is... GH The total focal length f of the wide-angle low-distortion lens satisfies the condition: 3.0 ≥ |f GH / f│≥2.0.
[0011] Furthermore, the focal length f of the meniscus negative lens I I The total focal length f of the wide-angle low-distortion lens satisfies the condition: 5.0 ≥ |f I / f│≥4.0.
[0012] Furthermore, the combined focal length f of the two lenses, the biconvex positive lens J and the crescent positive lens K, is... JK The total focal length f of the wide-angle low-distortion lens satisfies the condition: 3.0 ≥ |f JK / f│≥2.0.
[0013] The beneficial effects of this invention are as follows: This invention is a global near-infrared lens with wide-angle and low distortion characteristics. Its specific technical specifications are as follows: Wavelengths used: 980nm to 1070nm; Working distance: 400±10mm; Imaging range: 1-inch image plane, image height greater than ±8.0mm, field of view greater than ±51°; Distortion: less than 3.5%; Numerical aperture: F / 2.0; Image resolution requirement: MTF > 0.4 at 30 lp / mm; Image-side principal ray angle (CRA): less than 10°. Attached Figure Description
[0014] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0015] Figure 1 This is a schematic diagram of the structure of a wide-angle low-distortion lens for near-infrared applications according to the present invention. Figure 2 This is a diagram showing the lens parameters for Example 1; Figure 3 The distortion diagram is from Example 1; Figure 4 MTF plot of Example 1 Figure 5 This is the CRA angle diagram of the principal ray in Example 1; Figure 6 This is a diagram showing the lens parameters for Example 2; Figure 7 This is a diagram showing the lens parameters for Example 3; Figure 8 This is a diagram showing the lens parameters for Example 4.
[0016] The reference numerals in the diagram are: 1-Meniscus negative lens A, 2-Meniscus negative lens B, 3-Meniscus negative lens C, 4-Biconvex positive lens D, 5-Biconvex positive lens E, 6-Crescent positive lens F, 7-Variable aperture S, 8-Meniscus negative lens G, 9-Crescent positive lens H, 10-Meniscus negative lens I, 11-Biconvex positive lens J, 12-Crescent positive lens K. Detailed Implementation
[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Example 1
[0018] Reference Figure 1-5 A wide-angle, low-distortion lens for near-infrared applications, comprising, from the object plane to the image plane, a coaxial meniscus negative lens A1, a meniscus negative lens B2, a meniscus negative lens C3, a biconvex positive lens D4, a biconvex positive lens E5, a crescent positive lens F6, a variable aperture S7, a meniscus negative lens G8, a crescent positive lens H9, a meniscus negative lens I10, a biconvex positive lens J11, and a crescent positive lens K12.
[0019] The light beam originates from the object plane 400mm away from the lens on the left, passes through meniscus negative lens A1, meniscus negative lens B2, meniscus negative lens C3, biconvex positive lens D4, biconvex positive lens E5, and crescent positive lens F6, then passes through variable stop S7, and finally through meniscus negative lens G8, crescent positive lens H9, meniscus negative lens I10, biconvex positive lens J11, and crescent positive lens K12, before focusing onto the image plane on the right. Variable stop S7 limits the aperture of the entire light beam, and the parameter distribution of the other lenses needs to correct for spherical aberration, coma, astigmatism, field curvature, axial chromatic aberration, magnification chromatic aberration, and distortion.
[0020] The first three lenses use negative lenses to reduce the principal ray height and angle of incidence, while also correcting part of the second-order spectrum and field curvature, preparing for focusing by the subsequent positive lens. To reduce spherical aberration, the first two lenses use high-refractive-index glass, and the third negative lens uses anomalous dispersion glass to correct field curvature and the second-order spectrum.
[0021] Furthermore, in this embodiment, the meniscus negative lens A1 is H-ZLAF92, the meniscus negative lens B2 is H-ZLAF53B, and the meniscus negative lens C3 is H-ZPK5.
[0022] Furthermore, the total focal length f and total length L of the wide-angle low-distortion lens satisfy the condition: f / L=0.093.
[0023] Furthermore, the combined focal length f of the three lenses—meniscus negative lens A1, meniscus negative lens B2, and meniscus negative lens C3—is... ABC The total focal length f of the wide-angle low-distortion lens satisfies the condition: |f ABC / f│=1.8.
[0024] Furthermore, the combined focal length f of the two biconvex positive lenses D4 and E5 is... DE The total focal length f of the wide-angle low-distortion lens satisfies the condition: |f DE / f│=2.43.
[0025] Furthermore, the focal length f of the crescent-shaped positive lens F6 F The total focal length f of the wide-angle low-distortion lens satisfies the condition: |f F / f│=11.68.
[0026] Furthermore, the combined focal length f of the meniscus negative lens G8 and the crescent positive lens H9 is... GH The total focal length f of the wide-angle low-distortion lens satisfies the condition: |f GH / f│=2.55.
[0027] Furthermore, the focal length f of the meniscus negative lens I10 I The total focal length f of the wide-angle low-distortion lens satisfies the condition: |f I / f│=4.88.
[0028] Furthermore, the combined focal length f of the two lenses, the biconvex positive lens J11 and the crescent positive lens K12, is... JK The total focal length f of the wide-angle low-distortion lens satisfies the condition: |f JK / f│=2.61.
[0029] The lens parameters in this embodiment are as follows: Figure 2The wavelength used in this embodiment is 980nm to 1070nm, the working distance is 400±10mm, the aperture is better than F / 2.0, and it can achieve a resolution of 30lp / mm and low distortion performance.
[0030] like Figure 3 The diagram shown is a distortion graph for this embodiment, where the horizontal axis represents the distortion percentage and the vertical axis represents the field of view. Lens distortion causes image deformation and distortion. This embodiment can image a one-inch image plane with a corresponding object-side field of view greater than ±51°, achieving a distortion of less than 3.5%.
[0031] like Figure 4 The figure shows the MTF graph of this embodiment, where the horizontal axis represents the image height and the vertical axis represents the OTF modulus (MTF). The OTF modulus (MTF) is the most important indicator for describing the resolution of an optical imaging system. Regardless of whether it is in the meridional (solid line in the figure) or sagittal (dashed line in the figure) direction, the MTF of this embodiment can achieve 30 lp / mm > 0.4 in the image plane.
[0032] like Figure 5 As shown, this represents the principal ray angle (CRA) in this embodiment, where the horizontal axis represents the image height and the vertical axis represents the incident angle of the principal ray on the image plane. A large principal ray angle (CRA) on the image plane will reduce the camera's response efficiency; this embodiment achieves a CRA angle < 10°.
[0033] In summary, this embodiment is a global near-infrared lens, featuring wide-angle and low-distortion characteristics. Its specific technical specifications are summarized below: Wavelengths used: 980nm to 1070nm; Working distance: 400±10mm; Imaging range: 1-inch image plane, image height greater than ±8.0mm, field of view greater than ±51°; Distortion: less than 3.5%; Numerical aperture: F / 2.0; Image resolution requirement: MTF > 0.4 at 30 lp / mm; Image-side principal ray angle (CRA): less than 10°. Example 2
[0034] Reference Figure 1 A wide-angle, low-distortion lens for near-infrared applications, comprising, from the object plane to the image plane, a coaxial meniscus negative lens A1, a meniscus negative lens B2, a meniscus negative lens C3, a biconvex positive lens D4, a biconvex positive lens E5, a crescent positive lens F6, a variable aperture S7, a meniscus negative lens G8, a crescent positive lens H9, a meniscus negative lens I10, a biconvex positive lens J11, and a crescent positive lens K12.
[0035] Furthermore, the total focal length f and total length L of the wide-angle low-distortion lens satisfy the condition: f / L=0.090.
[0036] Furthermore, the combined focal length f of the three lenses—meniscus negative lens A1, meniscus negative lens B2, and meniscus negative lens C3—is... ABC The total focal length f of the wide-angle low-distortion lens satisfies the condition: |f ABC / f│=1.79.
[0037] Furthermore, the combined focal length f of the two biconvex positive lenses D4 and E5 is... DE The total focal length f of the wide-angle low-distortion lens satisfies the condition: |f DE / f│=2.50.
[0038] Furthermore, the focal length f of the crescent-shaped positive lens F6 F The total focal length f of the wide-angle low-distortion lens satisfies the condition: |f F / f│=11.48.
[0039] Furthermore, the combined focal length f of the meniscus negative lens G8 and the crescent positive lens H9 is... GH The total focal length f of the wide-angle low-distortion lens satisfies the condition: |f GH / f│=2.52.
[0040] Furthermore, the focal length f of the meniscus negative lens I10 I The total focal length f of the wide-angle low-distortion lens satisfies the condition: |f I / f│=4.59.
[0041] Furthermore, the combined focal length f of the two lenses, the biconvex positive lens J11 and the crescent positive lens K12, is... JK The total focal length f of the wide-angle low-distortion lens satisfies the condition: |f JK / f│=2.51.
[0042] Based on the above constraints, the lens parameter distribution in this embodiment is shown below. Figure 6 The wide-angle low-distortion lens for near-infrared in this embodiment can achieve the same optical performance as in Example 1. Example 3
[0043] Reference Figure 1 A wide-angle, low-distortion lens for near-infrared applications, comprising, from the object plane to the image plane, a coaxial meniscus negative lens A1, a meniscus negative lens B2, a meniscus negative lens C3, a biconvex positive lens D4, a biconvex positive lens E5, a crescent positive lens F6, a variable aperture S7, a meniscus negative lens G8, a crescent positive lens H9, a meniscus negative lens I10, a biconvex positive lens J11, and a crescent positive lens K12.
[0044] Furthermore, the total focal length f and total length L of the wide-angle low-distortion lens satisfy the condition: f / L=0.090.
[0045] Furthermore, the combined focal length f of the three lenses—meniscus negative lens A1, meniscus negative lens B2, and meniscus negative lens C3—is... ABC The total focal length f of the wide-angle low-distortion lens satisfies the condition: |f ABC / f│=1.81.
[0046] Furthermore, the combined focal length f of the two biconvex positive lenses D4 and E5 is... DE The total focal length f of the wide-angle low-distortion lens satisfies the condition: |f DE / f│=2.51.
[0047] Furthermore, the focal length f of the crescent-shaped positive lens F6 F The total focal length f of the wide-angle low-distortion lens satisfies the condition: |f F / f│=12.99.
[0048] Furthermore, the combined focal length f of the meniscus negative lens G8 and the crescent positive lens H9 is... GH The total focal length f of the wide-angle low-distortion lens satisfies the condition: |f GH / f│=2.53.
[0049] Furthermore, the focal length f of the meniscus negative lens I10 I The total focal length f of the wide-angle low-distortion lens satisfies the condition: |f I / f│=4.91.
[0050] Furthermore, the combined focal length f of the two lenses, the biconvex positive lens J11 and the crescent positive lens K12, is... JK The total focal length f of the wide-angle low-distortion lens satisfies the condition: |f JK / f│=2.61.
[0051] Based on the above constraints, the lens parameter distribution in this embodiment is shown below. Figure 7 The wide-angle low-distortion lens for near-infrared in this embodiment can achieve the same optical performance as in Example 1. Example 4
[0052] Reference Figure 1A wide-angle, low-distortion lens for near-infrared applications, comprising, from the object plane to the image plane, a coaxial meniscus negative lens A1, a meniscus negative lens B2, a meniscus negative lens C3, a biconvex positive lens D4, a biconvex positive lens E5, a crescent positive lens F6, a variable aperture S7, a meniscus negative lens G8, a crescent positive lens H9, a meniscus negative lens I10, a biconvex positive lens J11, and a crescent positive lens K12.
[0053] Furthermore, the total focal length f and total length L of the wide-angle low-distortion lens satisfy the condition: f / L=0.093.
[0054] Furthermore, the combined focal length f of the three lenses—meniscus negative lens A1, meniscus negative lens B2, and meniscus negative lens C3—is... ABC The total focal length f of the wide-angle low-distortion lens satisfies the condition: |f ABC / f│=1.77.
[0055] Furthermore, the combined focal length f of the two biconvex positive lenses D4 and E5 is... DE The total focal length f of the wide-angle low-distortion lens satisfies the condition: |f DE / f│=2.44.
[0056] Furthermore, the focal length f of the crescent-shaped positive lens F6 F The total focal length f of the wide-angle low-distortion lens satisfies the condition: |f F / f│=11.57.
[0057] Furthermore, the combined focal length f of the meniscus negative lens G8 and the crescent positive lens H9 is... GH The total focal length f of the wide-angle low-distortion lens satisfies the condition: |f GH / f│=2.47.
[0058] Furthermore, the focal length f of the meniscus negative lens I10 I The total focal length f of the wide-angle low-distortion lens satisfies the condition: |f I / f│=4.51.
[0059] Furthermore, the combined focal length f of the two lenses, the biconvex positive lens J11 and the crescent positive lens K12, is... JK The total focal length f of the wide-angle low-distortion lens satisfies the condition: |f JK / f│=2.52.
[0060] Based on the above constraints, the lens parameter distribution in this embodiment is shown below. Figure 8 The wide-angle low-distortion lens for near-infrared in this embodiment can achieve the same optical performance as in Example 1.
[0061] The above description is only a preferred embodiment of the present invention and is 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 within the protection scope of the present invention.
Claims
1. A wide-angle, low-distortion lens for near-infrared applications, characterized in that: From the object plane to the image plane, the lenses are arranged in sequence along the same axis: meniscus negative lens A, meniscus negative lens B, meniscus negative lens C, biconvex positive lens D, biconvex positive lens E, crescent positive lens F, variable stop S, meniscus negative lens G, crescent positive lens H, meniscus negative lens I, biconvex positive lens J, and crescent positive lens K.
2. The wide-angle low-distortion lens for near-infrared as described in claim 1, characterized in that: The total focal length f and total length L of the wide-angle low-distortion lens satisfy the condition: f / L≥0.
085.
3. The wide-angle low-distortion lens for near-infrared as described in claim 1, characterized in that: The combined focal length f of the three lenses, meniscus negative lens A, meniscus negative lens B, and meniscus negative lens C, is... ABC The total focal length f of the wide-angle low-distortion lens satisfies the condition: 2.0 ≥ |f ABC / f│≥1.
5.
4. The wide-angle low-distortion lens for near-infrared as described in claim 1, characterized in that: The combined focal length f of the two biconvex lenses D and E is... DE The total focal length f of the wide-angle low-distortion lens satisfies the condition: 3.0 ≥ |f DE / f│≥2.
0.
5. The wide-angle low-distortion lens for near-infrared as described in claim 1, characterized in that: The focal length f of the crescent-shaped positive lens F F The total focal length f of the wide-angle low-distortion lens satisfies the condition: |f F / f│≥10.
0.
6. The wide-angle low-distortion lens for near-infrared as described in claim 1, characterized in that: The combined focal length f of the meniscus negative lens G and the crescent positive lens H is... GH The total focal length f of the wide-angle low-distortion lens satisfies the condition: 3.0 ≥ |f GH / f│≥2.
0.
7. The wide-angle low-distortion lens for near-infrared as described in claim 1, characterized in that: The focal length f of the meniscus negative lens I I The total focal length f of the wide-angle low-distortion lens satisfies the condition: 5.0 ≥ |f I / f│≥4.
0.
8. The wide-angle low-distortion lens for near-infrared as described in claim 1, characterized in that: The combined focal length f of the two lenses, the biconvex positive lens J and the crescent positive lens K, is... JK The total focal length f of the wide-angle low-distortion lens satisfies the condition: 3.0 ≥ |f JK / f│≥2.0.