The influence of different pattern facula on four-quadrant detectors(QD) is studied and the gaussian-distributed facula is researched in brief.The testing device is set up,which can accomplish performance testing with scanning galvanometric and CCD camera.The experimental results show that facula detection accuracy of figure algorithm is 5 times than that of centroides.With limited sensitivity,2-subdivision is achieved only,and smoothing filter can be applied to improve the ability of subdivision.With high ...