Simultaneous Analysis of Two Phase Components for Moiré Interferometry by Two-directional Integrated Phase-shifting Method

Abstract

A new approach to simultaneous measurement of two different displacement fields by two-directional integrated phase-shifting for moire interferometry is proposed in order to enable the analysis of time-varying problems. Two moire fringe patterns for both of two displacement components produced simultaneously by four-beam interference are recorded as a single image. Then, the phase distributions representing both displacements are separated and obtained from a series of 12 images by adopting simultaneous phase-shifting for both directions. An example problem of rigid body rotation with carrier fringes is demonstrated by use of the proposed method and the effectiveness is shown. It is emphasized that measurement and subsequent analysis can be carried out in real-time since the phase-shifting is performed without stopping and images are recorded successively in the proposed method.