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摘要:
智慧汽车的发展对具备投影功能的智能车灯系统提出了更高的要求。Micro LED投影显示技术因其良好的自发光特性使之与传统技术相比系统结构更为简单，光利用率更高，更有利于小型化、节能化和集成化。本文提出了一种基于Micro LED阵列的车灯投影方案，设计了以像素尺寸为80 μm×80 μm的200×150白光Micro LED阵列作为显示光源，视场角为16°×34°物像倾斜的车灯投影光学系统，对物面倾斜角度和光学系统结构进行了优化。此外，分别采用反向畸变处理方法和像素灰度调制方法解决车灯投影图像的梯形畸变和照度均匀性问题，并搭建了投影实验平台，对图像校正方法进行了验证。实验结果表明：校正后x、y方向的图像梯形畸变系数分别从0.0932和0.3680下降至0.0835和0.0373，像面照度均匀性从83.2%提高到93.2%。本文通过基于Micro LED的倾斜投影车灯光学系统优化设计及其图像校正方法，实现了高光效、低畸变的车灯投影。
Abstract:The development of smart cars puts forward higher requirements for intelligent light systems with projection functions. Compared with the vehicle light system using traditional technology, the vehicle light system using Micro LED projection display technology can make the system structure simpler and the light utilization rate higher, which is more conducive to miniaturization, energy saving and integration because of its good self-luminous characteristics. In this paper, we propose a light projection scheme based on Micro LED array, design a 200×150 white Micro LED array with a pixel size of 80 μm×80 μm as the display light source and the field of view angle is 16°×34° object image tilt, and optimize the tilt angle and optical system structure of the object surface. In addition, the reverse distortion processing method and the pixel grayscale modulation method are used to solve the problems of keystone distortion and illumination uniformity of the projected image of the vehicle light, and a projection experimental platform is built to verify the image correction method. The experimental results show that the keystone distortion coefficients of the corrected images in the x and y directions decrease from 0.0932 and 0.3680 to 0.0835 and 0.0373, respectively, and the uniformity of the illumination of the image surface increases from 83.2% to 93.2%. In this paper, the optimization design of the oblique projection vehicle lighting system based on Micro LED and its image correction method are used to realize the projection of the vehicle light with high luminous efficiency and low distortion.
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图 1 Micro LED车灯投影系统结构示意图
Figure 1. Structural schematic of Micro LED headlight projection system
图 5 光学系统成像质量评价分析图
Figure 5. Analytical diagram for the evaluation of the imaging quality of the optical system
图 6 优化后的车灯投影光学系统光路图
Figure 6. Optimized optical path diagram of the headlight projection optical system
图 8 不同温度下系统各视场的MTF图
Figure 8. MTF diagram for each field of view of the system at different temperatures
图 17 校正输出图像的照度分布
Figure 17. Correction of the illumination distribution of the output image
表 1 车灯投影系统Micro LED阵列参数
Table 1. Parameters for Micro LED arrays for the vehicle light projection systems
指标 参数 像素尺寸/μm 80×80 像素数量 200×150 阵列尺寸/mm 16×12 总光通量/lm 2000 
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表 2 投影物镜关键参数及设计指标
Table 2. Key parameters and design specifications for projection objectives
指标 参数 工作波段 400−700 nm F数 2 视场 16°(V)×34°(H) 焦距 40 mm MTF ≥0.5@0.0125 lp/mm（−20 °C~80 °C）
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表 3 系统公差表
Table 3. Table of system tolerance parameters
参数 值 曲率半径/N 3 表面不规则度ΔN 0.3 厚度/mm 0.02 表面偏心/mm 0.01 表面倾斜/° 0.02 折射率公差 0.001 阿贝数公差 1% 装调偏心/mm 0.03 装调倾斜/° 0.05
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表 4 光学系统公差分析结果
Table 4. Optical system tolerance analysis results
参数 值 名义值 0.720 最佳值 0.725 最差值 0.456 平均值 0.680 标准差 0.060
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表 5 校正前后图像梯形畸变对比
Table 5. Comparison of image trapezoidal distortion before and after correction
梯形畸变系数 校正前 校正后 p1 0.0932 0.0835 P2 −0.3680 −0.0373
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[1] 姜虹. LED远近光一体化前照灯光学设计[D]. 上海: 复旦大学, 2014.JIANG H. A lighting design of LED high and low beam integration headlapms[D]. Shanghai: Fudan University, 2014. (in Chinese) (查阅网上资料, 未找到对应的英文翻译, 请确认) [2] 张启宇, 李大航, 李运飞, 等. 中国乘用车前照灯先进技术与发展趋势浅析[J]. 汽车实用技术,2021,46(12):195-196,199.ZHANG Q Y, LI D H, LI Y F, et al. Analysis on the advanced technology and development trend of Chinese passenger car headlamp[J]. Automobile Applied Technology, 2021, 46(12): 195-196,199. (in Chinese) [3] 王鑫. 驶向未来: 梅赛德斯-奔驰F 015和它的无人驾驶朋友们[J]. 中国汽车市场,2015(8):24-29.WANG X. Drive to the future: Mercedes-Benz F 015 and its driverless friends[J]. China Auto Market, 2015(8): 24-29. (in Chinese) [4] TAKI T, STRASSBURG M. Review-visible LEDs: more than efficient light[J]. ECS Journal of Solid State Science and Technology, 2020, 9(1): 015017. doi: 10.1149/2.0402001JSS [5] 魏岚. 智己L7: 智能化角色亮眼[J]. 智能网联汽车,2022(2):90-91.WEI L. Zhiji L7: Intelligent characters are eye-catching[J]. Intelligent Connected Vehicles, 2022(2): 90-91. (in Chinese) [6] SUN W S, TIEN C L, MA CH H, et al. Compact LED projector design with high uniformity and efficiency[J]. Applied Optics, 2014, 53(29): H227-H232. doi: 10.1364/AO.53.00H227 [7] PAN J W, WANG C M, LAN H C, et al. Homogenized LED-illumination using microlens arrays for a pocket-sized projector[J]. Optics Express, 2007, 15(17): 10483-10491. doi: 10.1364/OE.15.010483 [8] SUN W S, PAN J W. Non-telecentric projection lens design for an LED projector[J]. Applied Optics, 2017, 56(3): 712-720. doi: 10.1364/AO.56.000712 [9] WU Y F, MA J SH, SU P, et al. Full-color realization of micro-LED displays[J]. Nanomaterials, 2020, 10(12): 2482. doi: 10.3390/nano10122482 [10] PARBROOK P J, CORBETT B, HAN J, et al. Micro‐light emitting diode: from chips to applications[J]. Laser &Photonics Reviews, 2021, 15(5): 2000133. [11] 赵永周. Micro-LED阵列显示器件制备及光电特性研究[D]. 长春: 中国科学院大学(中国科学院长春光学精密机械与物理研究所), 2022.ZHAO Y ZH. Research on the fabrication and photoelectric characterization of Micro-LEDs[D]. Changchun: Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, 2022. (in Chinese) [12] 冯思悦, 梁静秋, 梁中翥, 等. LED微阵列投影系统设计[J]. 中国光学,2019,12(1):88-96. doi: 10.3788/co.20191201.0088FENG S Y, LIANG J Q, LIANG ZH ZH, et al. Design of projection system for a Micro-LED array[J]. Chinese Optics, 2019, 12(1): 88-96. (in Chinese) doi: 10.3788/co.20191201.0088 [13] FAN K L, TAO J, ZHAO Y ZH, et al. Size effects of AlGaInP red vertical micro-LEDs on silicon substrate[J]. Results in Physics, 2022, 36: 105449. doi: 10.1016/j.rinp.2022.105449 [14] ZHAO Y ZH, LIANG J Q, ZENG Q, et al. 2000 PPI silicon-based AlGaInP red micro-LED arrays fabricated via wafer bonding and epilayer lift-off[J]. Optics Express, 2021, 29(13): 20217-20228. doi: 10.1364/OE.428482 [15] 邰建鹏, 郭伟玲, 李梦梅, 等. GaN基微缩化发光二极管尺寸效应和阵列显示[J]. 物理学报,2020,69(17):177301. doi: 10.7498/aps.69.20200305TAI J P, GUO W L, LI M M, et al. GaN based micro-light-emitting diode size effect and array display[J]. Acta Physica Sinica, 2020, 69(17): 177301. (in Chinese) doi: 10.7498/aps.69.20200305 [16] PARK S H, HONG A, KIM J H, et al. Highly bright yellow-green-emitting CuInS2 colloidal quantum dots with core/shell/shell architecture for white light-emitting diodes[J]. ACS Applied Materials &Interfaces, 2015, 7(12): 6764-6771. [17] 中华人民共和国住房和城乡建设部. CJJ 45-2015 城市道路照明设计标准[S]. 北京: 中国建筑工业出版社, 2016.Ministry of Housing and Urban-Rural Development of the People's Republic of China. CJJ 45-2015 Standard for lighting design of urban road[S]. Beijing: China Architecture & Building Press, 2016. (in Chinese) [18] STEGER C, ULRICH M, WIEDEMANN C. 机器视觉算法与应用[M]. 杨少荣, 吴迪靖, 段德山, 译. 北京: 清华大学出版社, 2008.STEGER C, ULRICH M, WIEDEMANN C. Machine Vision Algorithms and Applications[M]. YANG SH R, WU D J, DUAN D SH, trans. Beijing: Tsinghua University Press, 2008. (in Chinese) [19] 王振东. 宽波段成像光学系统设计[D]. 西安: 西安工业大学, 2022.WANG ZH D. Design of wide-band imaging optical system[D]. Xi’an: Xi’an Technological University, 2022. (in Chinese) [20] 刘韬. 考虑热致面型变化的消热差光学设计方法研究[D]. 长春: 中国科学院大学(中国科学院长春光学精密机械与物理研究所), 2022.LIU T. Research on athermal optical design method considering thermal-induced surface deformation[D]. Changchun: Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, 2022. (in Chinese) [21] 翟玉生, 杨犇, 张志峰, 等. 基于平面互补靶标的线结构光标定系统[J]. 应用光学,2023,44(2):371-379. doi: 10.5768/JAO202344.0203002ZHAI Y SH, YANG B, ZHANG ZH F, et al. Line structured light calibration system based on planar complementary target[J]. Journal of Applied Optics, 2023, 44(2): 371-379. (in Chinese) doi: 10.5768/JAO202344.0203002 [22] 孙丽君, 张丹丹, 陈天飞, 等. 一种基于局部单应性的投影仪精确标定方法[J]. 激光与光电子学进展,2022,59(13):1312003.SUN L J, ZHANG D D, CHEN T F, et al. Accurate local homography-based projector calibration method[J]. Laser &Optoelectronics Progress, 2022, 59(13): 1312003. (in Chinese) [23] 周舵, 王鹏, 孙长库, 等. 投影仪和双相机组成的三目立体视觉系统标定方法[J]. 光学学报,2021,41(11):1115001. doi: 10.3788/AOS202141.1115001ZHOU D, WANG P, SUN CH K, et al. Calibration method for trinocular stereovision system comprising projector and dual cameras[J]. Acta Optica Sinica, 2021, 41(11): 1115001. (in Chinese) doi: 10.3788/AOS202141.1115001 -
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