Abstract: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.