LED阵列模组化中的照度均匀性问题

Study on Uniformity of LED Array Illumination Distribution on Target Plane

为使LED阵列在目标面上产生均匀的照度分布,构建一个均匀度评价函数.通过优化阵列中各LED的位置,使得评价函数产生最小值,此时阵列在照明面上的均匀度最高.采用模拟退火算法对LED集成圆形阵列、4×4和4×5的矩形阵列进行优化,优化后的阵列在目标面上均产生了均匀照度分布,对应的均匀度分别为97%、96%和95%.对LED阵列中影响目标面均匀照度的参量进行研究,结果表明圆形阵列的最佳半径与LED的颗数无关,阵列面和目标面之间的距离与阵列的最佳半径呈线性关系;矩形阵列中,相邻LED之间的最佳距离与阵列面和目标面之间的距离呈线性关系.该方法与现有解析方法所得结果一致,且算法简单便捷,可用于计算机自动优化设计.

Global optimization algorithm was proposed to optimize and design LED array for generating uniform illumination distribution on target plane. An evaluation function reflecting illumination uniformity was constructed, which can reach the minimum by optimizing the LEDs positions. While the evaluation function takes the minimum value, the optimal LED array can produce highly uniform illumination distribution on target plane. The minimum value of evaluation function was found by simulated annealing algorithm, so that the circular array consisting of 12 LEDs, 4 X 4 and 4 ）〈 5 rectangular LED array were optimized. After optimization, the three arrays produce highly uniform illumination distribution with the calculated uniformity 97o//oo, 96 % and 95 ~, respectively. The results show that the optimal radius of circular array does not depend on the number of LEDs. The optimal radius depends linearly on the distance between LED array plane and the target plane. For the rectangular array, the optimal separation between adjacent LEDs depends linearly on the distance between LED array plane and the target plane. The results of the proposed method were consistent with existing method, and the algorithm is simple and convenient.