在分析四象限位置敏感器件（4QPSD）结构及特点的基础上，利用该器件作为核心探测器，设计了一种光电探测系统，对高分辨率横向位移的探测进行了研究。系统主要包括LED光发射、光接收、信号处理和显示等部分。LED发射的光束经聚焦透镜汇聚后射向反射镜，反射光聚焦到一个4QPSD上，经线性化的信号处理电路处理后，可实现高分辨率横向位移的测量。实验证明：横向位移测量稳定性与精度与测量距离无关，系统的误差主要来自反射镜反射的非均匀性。

Based on analyzing the structure and characteristics of fourquadrant position sensitive detector, a photoelectric detection system was designed by using the device as the core detector, and then the detection of highresolution lateral displacement was studied. The system mainly consists of LED optical transmitter, optical receiver, signal processing and display part. The light beams emitting by LED were converged by the focusing lens shot at the mirror, and then the reflected light was focused to a fourquadrant position sensitive detector. Highresolution lateral displacement measurement can be achieved by the linearized signal processing circuit. Experimental results show that stability and accuracy of lateral displacement measurement has nothing to do with the measuring distance, and the detection errors mainly come from the reflected heterogeneity of the reflective film.