Strain Distribution Measurement by Digital Holographic Interferometry Using Three Spherical Waves

摘要

In this paper, we proposed a calibration method with a reference plane to analyze strain distribution using three spherical waves in independent directions. The relationship between the phase difference and displacement for each pixel are determined for one beam using a reference plane. When this measurement is performed for each of three beams, the sensitivity matrix for each pixel can be obtained independently. We also proposed a phase analysis method using Fourier transform for a wave composed by three waves. Three spherical waves are irradiated onto the reference plane or an object simultaneously. The principle and the experimental results of strain measurement are shown.