Phase-shifting whole-field speckle photography technique for the measurement of in-plane deformations in real time

A new real-time phase-shifting readout system is developed for quantitative evaluation of full-field correlation fringes obtained by means of Fourier filtering in speckle photography. The proposed method, which uses photorefractive crystals as the recording medium, is capable of mapping the whole-field displacement data from the recorded phase-shifted fringe patterns. Experimental results are presented on a diffuse surface subjected to rotation in its own plane.