OPTICAL PHASE CONTROLLER FOR PHASE SHIFT INTERFEROMETER FOR PLANE MEASUREMENT AND OPTICAL PHASE CONTROL METHOD FOR THE SAME, AND STORAGE MEDIUM WITH OPTICAL PHASE CONTROL PROGRAM

摘要

PROBLEM TO BE SOLVED: To provide the optical phase controller and method of a phase shift interferometer for plane measurement for operating highly accurate phase shift, without using special devices and a storage medium storing an optical phase control program.;SOLUTION: A phase for minimizing a difference value between the maximum value and a minimum value for the brightness intensity of the mutual pixels of an interference fringe picture (image I) at a phase 0 and an interference fringe image (second image IIA), obtained by shifting the phase of the first picture is obtained. Thus, interference fringe images can be obtained at the phase 0 and a phase 180, and to obtain an interference fringe image at a phase 90 by calculating the intermediate position of the center of gravity position of the interference fringes of the interference fringe images, and to obtain the phase shape of an object 1 to be measured by operating plane analysis based on the three interference fringe image.;COPYRIGHT: (C)2001,JPO