Full-Field Extraction of Isochromatic Parameter Using Photoelasticity Assisted by Phase-Shifting Technique

摘要

The goal of this paper is to propose a four-step phase shifting method to determine a fractional fringe order and an algorithm for determination of an isochromatic parameter or absolute fringe order. This method uses five full-colored fringe images simulated for a plane polariscope with three RGB wavelengths. The absolute fringe orders are demodulated from the RGB isochromatic phase map using a least-square method coupled with a governing relation and condition. This method is illustrated with those simulated fringe images of the problem of the circular disc subjected to diametrically compressive loads.