Signal will meet various interference during their transmission. In order toensure stablility of the signal, It is very important to use Signal isolator. Theimportance of the signal isolation study is highlighted from the wide application ofsignal isolators in industrial application.This paper firstly begins with background of series signal transmitter at home andabroad, and analyzes of the pros and cons of transmitters with different principles,then choose the selected linear optocoupler isolation technology.Secondly, automatic laser thickness measurement system is this design’s actualresearch background, so the working principles and methods of measurement arebriefly elaborated. Thirdly, the interference sources of automatic laser thicknessmeasurement system are analysed and related methods are put forward. And finallydesign based on a linear optocoupler HCNR200precision isolation circuit is proposed.Signal isolator of the design is divided into two parts high precision voltagemeasurement circuit and switching regulator circuit. High precision voltagemeasurement circuit divided into the input part, isolation part and output part,.Circuitdesign principle diagram are respectively drew and simulated at mutlism10.0. At thesame time hardware circuits are also drew out at altium designer6.0and are made intoPCB board. Data processing software uses matlab7.0. The results show that thesignal isolating instruments have good isolation effect. |