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摘要:
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°的车灯投影光学系统,并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用以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:校正后图像梯形畸变系数
p 1,p 2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%。本文通过对基于Micro LED的倾斜投影车灯光学系统进行优化设计及采用图像校正方法,实现了高光效、低畸变的车灯投影。Abstract:This article presents a vehicle headlight projection scheme based on Micro LED arrays. A 200×150 white Micro LED array with pixel size of 80 μm×80 μm is designed as the display light source, and a headlight projection optical system with a field of view of 16°×34° is designed. The object plane tilt angle and optical system structure are optimized. In addition, the inverse distortion processing method and pixel grayscale modulation method are used to solve the trapezoidal distortion and uniformity of illumination of the headlight projection image. A projection experimental platform is built to verify the image correction method. Experimental results show that after correction, the image trapezoidal distortion coefficients
p 1 andp 2 decrease from 0.0932 and 0.3680 to 0.0835 and 0.0373, respectively, and the image plane illumination uniformity increases from 83.2% to 93.2%. This article achieves high light efficiency and low distortion of vehicle headlight projection by optimizing the design of the inclined projection headlight optical system based on Micro LEDs and using image correction methods. -
表 1 车灯投影系统Micro LED阵列参数
Table 1. Parameters of Micro LED arrays for vehicle headlight projection system
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 表 2 投影物镜的关键参数及设计指标
Table 2. Key parameters and design specifications for projection objective
指标 参数 工作波段/nm 400~700 F数 2 视场 16°(V)×34°(H) 焦距/mm 40 MTF ≥0.5@0.0125 lp/mm(−20 °C~80 °C) 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 表 4 光学系统公差分析结果
Table 4. Tolerance analysis results of optical system
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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