This paper discusses the key problem of measurement accuracy in a precise photo electronic measurement system with large field of view

and high accurate geometric calibrationmethod in the system. The highlight is put on the approches of compensating the geometricdistortion of optical system with the analytic method using computer

in order to obtain ahigh accuracy. The major problemes studied are sa follows:the analysis of the basic photogrammetry method and study of distortion calibration and camera calibration;the mathematic model of to camera calibrtion and distortion;the method of calibrating the camera;themethod of analyzing the calibration results;the computer emulation experiment and the analysis of the results.