Study On Technology Of Detecting Synchronously Multiple Light Beams Based On Position-Sensitive Detector Phase Positioning Method

Position-Sensitive Detector (PSD) is the semiconductor component,measuring position displacement information of light spot based on the Lateral Photoeffect,which has multiple carriers of position information,including amplitude and phase that are two available carriers of information.All the time,people's researches are mainly focused on the amplitude positioning method,which is easily disturbed by background lights and noise.This method is limitary in applications.However,the phase positioning method, which is a quite promising technology, has the merits of high precision, simple signal processing circuits, strong ability of anti-interference,and so on. In this thesis, based on the comprehensive generalization and summarization of PSD Leteral Photoeffect,the theories of phase positioning method of PSD are studied according to the RC transmission line model of PSD.Phase response of PSD electrodes'output current is get. Further more,the effect of the peripheral circuits and modulating frequency on the linearity and the positioning resolution are also researched. In optoelectronic precision position measuring systems, utilizing less optoelectronic apparatus to get enough information from multiple light beams can improve system reliability and reduce cost.According to the thinking of detecting signal simultaneously ,and combining the method of frequency-divided multiplexing, the thesis's author introduces and studies the technology of detecting multiple light beams simultaneously based on the phase positioning method of PSD.The signal processing circuits and software programs for this technology is designed as well.And the experimental system of synchronous detection is made up of PSD,the circuit to process the signal for PSD phase positioning method,the A/D interface circuit,the LED lamp-house,power supply,computer and software.In addition,through the experiment of detecting multiple light beams simultaneously with one 1D-PSD and 2D-PSD respectively and separating signals from different frequency signals,the result proves the realization of simultaneous detection.Lastly,the experimental error of the multiple light beams simultaneous detection is estimated. The error sources are analysed,and the methods to eliminate or weaken their affects are provided. This research work in the thesis offers a new and effective method for multiple light beams simultaneous detection.