A Design Method for LEDs Arrays Structure Illumination

作者:Wu, Fupei*; Li, Shengping; Zhang, Xianmin; Ye, Weilin
来源:Journal of Display Technology, 2016, 12(10): 1177-1184.
DOI:10.1109/JDT.2016.2593770

摘要

Capturing high quality image is very important in the active automatic optical inspection system. Besides camera, image quality mainly is affected by the illumination. A design method of structure illumination, which is comprised of light emitting diodes (LEDs) arrays, is proposed in this paper. And especially, these LEDs arrays are not in the same plane. First, the single LED irradiating model is built based on analyzing its irradiance properties. Second, the case of two LEDs irradiating is set as an example to analyze superposition properties of the same color light for any specified point's light brightness based on the built single LED irradiating model, and then the irradiating model of LEDs is developed. Third, the structure illumination design method of LEDs ring arrays is illustrated based on the proposed design model of illumination uniformity. Especially, the illumination design method is decomposed into two subproblems to simplify the design process, which can reduce the design difficulty. Experimental results show that the light intensity deviation is less than 3.78% by the proposed illumination design method, which validates the effectiveness of the proposed method.