Vibration errors in phase-shifting interferometer with absolute testing

Abstract

Requirements for the measurement resolution in the sub-nanometer range have become quite common. Result of the testing contain the reference surface errors and test surface errors in the high-accuracy Phase shifting interferometer (PSI) which test the relative phase between the two surface. The test accuracy can be achieved by removing the error of reference surface. In this case, one of body of so-called absolute tests must be used which can test the systematic errors, including the reference surface, of the instrument to be used to improve the test accuracy. Unexpected mechanical vibrations can significantly degrade the otherwise high accuracy of phase-shifting interferometer. The data acquisition is sensitivity to vibration with a function of the frequency. The influence of the longitudinal vibration is analyzed in this paper. We use Zernike polynomials to generate 3 plats. Then the Matlab is used to simulate the 4 frames phase-shift algorithms and absolute testing algorithms. An experiment used the Zygo interferometer to prove the arithmetic and we can see the vibration errors in the testing.