Simultaneous measurement of displacement, strain and curvature in digital holographic interferometry using high-order instantaneous moments.

Analysis of strain and the study of flexural moments of a deformed object is of utmost importance in non-destructive testing and evaluation. In digital holographic interferometry (DHI), this information is provided, respectively, by the first and second-order derivatives of the interference phase. This paper introduces high-order instantaneous moments based approach for the simultaneous measurement of displacement, strain and curvature distributions of a deformed object in DHI. Simulation and experimental results are presented to demonstrate the ability of the proposed method in accurately providing the direct estimation of the unwrapped distributions corresponding to the interference phase and its derivatives in a computationally efficient manner.