光电成像检测系统像面照度均匀性分析

Illuminance uniformity of image plane in photoelectronic image testing system

非均匀发光光源、大视场角等因素会造成光学成像检测系统像面照度分布不均匀,进而导致检测效率下降。研究非均匀发光光源和大视场角对像面照度均匀性的影响程度,首先建立光源间距与受光面接收照度间的关系模型,仿真分析不同LED间距对像面照度均匀性的影响,然后建立光学耦合系统的物面张角和像面照度间的关系模型,仿真分析物面张角对像面照度均匀性的影响。实验结果表明:在非均匀发光光源和大视场角的作用下,检测系统会造成像面照度严重不均匀现象。研究结果为后续像面照度校正算法设计提供了理论依据。

Non-uniform light source and wide field angle were two causes for illumination nonuniformity of image plane in photoelectronic image testing system.To study the influence,the relationship model between spacing of LED light source and image plane illumination was built.The influence of different LED intervals on image plane illumination was simulated and analyzed.The relationship model between opening angle of object plane of optical coupling system and image plane illumination was established,and the influence of opening angle of object plane on illuminance uniformity of image plane was simulated and studied.The experiment results show that non-uniform light source and wide field angle are two main causes for non-uniformity illumination of image plane,which provides the theoretical basis for designing better corresponding correction algorithm.