10-degree field-of-view long-wave infrared lens for unmanned aerial vehicle
By designing a 10° field-of-view long-wave infrared lens for UAVs, and employing specific lens materials and aspherical structures, the problem of unclear imaging in high-altitude environments was solved, achieving efficient and stable imaging results.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-21
- Publication Date
- 2026-03-06
AI Technical Summary
Existing aviation optical lenses struggle to maintain clear imaging under varying temperature and air pressure conditions at high altitudes, and their anti-interference capabilities are insufficient, especially when there are significant temperature differences between the ground and the air, affecting detection and identification performance.
Design a 10° field-of-view long-wave infrared lens for UAVs, employing a first positive meniscus lens, a negative meniscus lens, a second positive meniscus lens, a window, and a filter. The rear surface of the lens is aspherical, and the materials are IRG207, ZNSE, and GERMANIUM. The filter is used to filter out non-long-wave infrared light, and the lens barrel material is aluminum.
It achieves high imaging transfer function, low distortion, good uniformity and strong anti-interference, and is suitable for precise observation and measurement in a small area. The imaging quality is stable and is not affected by changes in ambient temperature.
Smart Images
Figure CN223977417U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of optical lens technology, specifically relating to a 10° field-of-view long-wave infrared lens for drones. Background Technology
[0002] Optical lenses used in the aviation field operate in high-altitude environments, requiring clear imaging of ground targets under constantly changing environmental parameters such as temperature and atmospheric pressure. Especially when there are significant temperature differences between the ground and the air, long-wave infrared lenses need strong anti-interference capabilities, as interference can easily lead to poor detection and identification performance. However, the optical designs of existing optical lenses do not meet these practical requirements. Utility Model Content
[0003] In view of this, the purpose of this utility model is to provide a 10° field-of-view long-wave infrared lens for UAVs, which has a high imaging transfer function, low distortion, and strong anti-interference ability.
[0004] To achieve the above objectives, the present invention adopts the following technical solution:
[0005] A 10° field-of-view long-wave infrared lens for drones includes a first positive meniscus lens, a negative meniscus lens, a second positive meniscus lens, a window, and a filter arranged coaxially along the direction of light propagation. The rear surfaces of the first positive meniscus lens, the negative meniscus lens, and the second positive meniscus lens are all aspherical. The filter is used to filter out light in the non-long-wave infrared band.
[0006] Furthermore, the first positive meniscus lens is made of IRG207, with radii of curvature of 55.84 mm and 111.3713 mm on its front and rear surfaces, respectively, and a thickness of 12.50 mm. The coefficient on r^4 of the rear surface of the first positive meniscus lens is 4.75e. -007 The coefficient on r^6 is -9.18e -011 The coefficient on r^8 is 2.59e. -014 ;
[0007] The negative meniscus lens is made of ZnSe, with radii of curvature of 58.74 mm and 37.32 mm on its front and rear surfaces, respectively, and a thickness of 6.00 mm. The coefficient on the r^4 of the rear surface of the negative meniscus lens is 1.08e. -006 The coefficient on r^6 is 5.60e. -010 The coefficient on r^8 is 6.84e. -013 The distance between the negative meniscus lens and the first positive meniscus lens is 5.31 mm.
[0008] The second positive meniscus lens is made of GERMANIUM, with radii of curvature of 108.32 mm and 168.90 mm on its front and rear surfaces, respectively, and a thickness of 5.50 mm. The coefficient on r^4 of the rear surface of the second positive meniscus lens is -5.25e. -007 The coefficient on r^6 is -6.07e -010 The coefficient on r^8 is -8.02e -014 The distance between the second positive meniscus lens and the negative meniscus lens is 37.84 mm.
[0009] The window is made of GERMANIUM and has a thickness of 2.00 mm; the distance between the window and the second positive meniscus lens is 10.92 mm.
[0010] The filter is made of GERMANIUM and has a thickness of 0.73 mm; the distance between the filter and the window is 12.00 mm, and the distance between the filter and the image plane is 1.41 mm.
[0011] Compared with the prior art, the beneficial effects of this utility model are as follows:
[0012] This utility model features a 10° field-of-view long-wave infrared lens for UAVs. It has a simple structure, a fixed 10° viewing angle, a high imaging transfer function, low distortion, good imaging clarity and uniformity, strong anti-interference capabilities, and the imaging quality of the optical lens is not significantly affected by large changes in ambient temperature. It is suitable for precise observation and measurement in small areas. Attached Figure Description
[0013] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0014] Figure 1 This is a schematic diagram of the structure of the 10° field-of-view long-wave infrared lens for UAVs of this utility model.
[0015] In the diagram, 1 is the first positive meniscus lens, 2 is the negative meniscus lens, 3 is the second positive meniscus lens, 4 is the window, and 5 is the filter.
[0016] Figure 2 This is the full-field MTF diagram of the optical lens in Embodiment 1 of this utility model;
[0017] Figure 3 This is the maximum distortion diagram of the optical lens in Embodiment 1 of this utility model across the entire field of view;
[0018] Figure 4 The illumination uniformity of the optical lens across the entire field of view in Embodiment 1 of this utility model;
[0019] Figure 5 This is the MTF diagram of the optical lens in Embodiment 1 of this utility model at -30℃ across the entire field of view;
[0020] Figure 6 This is the MTF diagram of the optical lens in Embodiment 1 of this utility model at 40°C across the entire field of view. Detailed Implementation
[0021] To further understand this utility model, preferred embodiments of this utility model are described below. However, it should be understood that these descriptions are only for further illustrating the features and advantages of this utility model, and not for limiting the scope of the claims of this utility model.
[0022] like Figure 1 As shown, the 10° field-of-view long-wave infrared lens for UAVs of this invention includes a first positive meniscus lens 1, a negative meniscus lens 2, a second positive meniscus lens 3, a window 4, and a filter 5, which are coaxially arranged from front to back along the direction of light propagation. The filter 5 is used to filter out light in non-long-wave infrared bands.
[0023] Light passes sequentially through the first positive meniscus lens 1, the negative meniscus lens 2, the second positive meniscus lens 3, the window 4, and the filter 5 before being imaged on the image plane.
[0024] In the above technical solution, the first positive meniscus lens 1 is made of IRG207, with radii of curvature of 55.84 mm and 111.37 mm on its front and rear surfaces, respectively, and a thickness of 12.50 mm. The negative meniscus lens 2 is made of ZNSE, with radii of curvature of 58.74 mm and 37.32 mm on its front and rear surfaces, respectively, and a thickness of 6.00 mm; the distance between the negative meniscus lens 2 and the first positive meniscus lens 1 is 5.31 mm. The second positive meniscus lens 3 is made of GERMANIUM, with radii of curvature of 108.32 mm and 168.90 mm on its front and rear surfaces, respectively, and a thickness of 5.50 mm; the distance between the second positive meniscus lens 3 and the negative meniscus lens 2 is 37.84 mm. The window plate 4 is made of GERMANIUM, with a thickness of 2.00 mm; the distance between the window plate 4 and the second positive meniscus lens 4 is 10.92 mm. The material of filter 5 is GERMANIUM, and the thickness is 0.73mm. The distance between filter 5 and window 4 is 12.00mm, and the distance between filter 5 and image plane is 1.41mm.
[0025] In the above technical solution, the rear surfaces of the first positive meniscus lens 1, the negative meniscus lens 2, and the second positive meniscus lens 3 are all aspherical, and the coefficient on r^4 of the rear surface of the first positive meniscus lens 1 is 4.75e. -007The coefficient on r^6 is -9.18e -011 The coefficient on r^8 is 2.59e. -014 The coefficient on r^4 of the rear surface of the negative meniscus lens 2 is 1.08e. -006 The coefficient on r^6 is 5.60e. -010 The coefficient on r^8 is 6.84e. -013 The coefficient on the r^4 of the rear surface of the second positive meniscus lens 3 is -5.25e. -007 The coefficient on r^6 is -6.07e -010 The coefficient on r^8 is -8.02e -014 .
[0026] This utility model discloses a 10° field-of-view long-wave infrared lens for drones. It may also include a lens barrel. The lens barrel is not particularly limited; it only needs to be able to fix the aforementioned first positive meniscus lens 1, negative meniscus lens 2, second positive meniscus lens 3, window 4, and filter 5. The lens barrel material is typically aluminum, with a coefficient of thermal expansion of 23.6e. -006 .
[0027] The terms used in this utility model generally have the meanings commonly understood by those skilled in the art, unless otherwise stated.
[0028] To enable those skilled in the art to better understand the technical solution of this utility model, the present utility model will be further described in detail below with reference to the embodiments.
[0029] In the following embodiments, various processes and methods not described in detail are conventional methods known in the art. Unless otherwise specified, the materials, reagents, apparatus, instruments, equipment, etc., used in the following embodiments are commercially available.
[0030] Example 1
[0031] The optical lens specifications are as follows: Size: Back focal length: 14.13mm; Maximum aperture: Full field of view MTF > 0.4 @ 30 lp / mm, maximum distortion in the full field of view < 1%; illuminance uniformity in the full field of view > 96%.
[0032] Based on the above technical specifications, the parameters of each optical element (radius, curvature, thickness, spacing, material, etc.) of the designed optical lens are shown in Table 1 and Table 2.
[0033] Table 1. Parameters of each optical element in the optical lens of Example 1
[0034]
[0035] Aspheric coefficients of surf2, surf4, and surf6 in Table 2 and Table 1.
[0036]
[0037]
[0038] Upon testing, the MTF of the optical lens in Example 1 across the entire field of view is as follows: Figure 2 As shown, the maximum distortion across the entire field of view is as follows: Figure 3 As shown, the uniformity of illumination across the entire field of view is as follows: Figure 4 As shown, the MTF at -30℃ across the entire field of view is as follows Figure 5 As shown, the MTF at 40°C across the entire field of view is as follows: Figure 6 As shown, the optical lens of Example 1 exhibits a high imaging transfer function, low distortion, good imaging clarity, good uniformity, and strong anti-interference capability.
[0039] Obviously, the above embodiments are merely examples for clear illustration and are not intended to limit the embodiments. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively list all embodiments here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.
Claims
1. A 10° field of view long wave infrared lens for unmanned aerial vehicles, characterized in that, The lens comprises a first positive meniscus lens (1), a negative meniscus lens (2), a second positive meniscus lens (3), a window sheet (4) and a filter (5) arranged coaxially in sequence along the propagation direction of light, and the rear surface of the first positive meniscus lens (1), the negative meniscus lens (2) and the second positive meniscus lens (3) are aspherical surfaces, and the filter (5) is used for filtering out non-long-wave infrared band light.
2. The 10° field of view long-wave infrared lens for unmanned aerial vehicles according to claim 1, wherein, The material of the first positive meniscus lens (1) is IRG207, the radii of curvature of the front and back surfaces are 55.84 mm and 111.37 mm respectively, the thickness is 12.5 mm, and the coefficients on r^4, r^6 and r^8 of the back surface of the first positive meniscus lens (1) are 4.75e -007 -9.18e -011 and 2.59e -014 respectively.
3. The 10° field of view long-wave infrared lens for unmanned aerial vehicles according to claim 1, wherein, The material of the negative meniscus lens (2) is ZNSE, the radii of curvature of the front and back surfaces are 58.74 mm and 37.32 mm respectively, the thickness is 6.00 mm, and the coefficients on r^4, r^6 and r^8 of the back surface of the negative meniscus lens (2) are 1.08e -006 , 5.60e -010 and 6.84e -013 respectively; the distance between the negative meniscus lens (2) and the first positive meniscus lens (1) is 5.31 mm.
4. The 10° field of view long-wave infrared lens for unmanned aerial vehicles according to claim 1, wherein, The material of the second positive meniscus lens (3) is GERMANIUM, the radii of curvature of the front and back surfaces are 108.32 mm and 168.90 mm respectively, the thickness is 5.50 mm, and the coefficients on r^4, r^6 and r^8 of the back surface of the second positive meniscus lens (3) are -5.25e -007 -6.07e -010 -8.02e -014 respectively; the distance between the second positive meniscus lens (3) and the negative meniscus lens (2) is 37.84 mm.
5. The 10° field of view long-wave infrared lens for unmanned aerial vehicles according to claim 1, wherein, The material of the window sheet (4) is GERMANIUM, and the thickness is 2.00 mm; the spacing between the window sheet (4) and the second positive meniscus lens (3) is 10.92 mm.
6. The 10° field of view long-wave infrared lens for unmanned aerial vehicles according to claim 1, wherein, The material of the filter (5) is GERMANIUM, and the thickness is 0.73 mm; the spacing between the filter (5) and the window sheet (4) is 12.00 mm, and the spacing between the filter (5) and the image surface is 1.41 mm.