Simultaneous three-dimensional deformation measuring based on a simple phase-shift device combination with tri-wavelength and three-CCD camera

A simple and effective phase-shift device is designed for the simultaneous and high-accuracy measurement of three-dimensional (3D) deformation using tri-wavelength electronic speckle pattern interferometry and a three-sensor charge-coupled device camera. The designed phase-shifter can provide tri-wavelength lasers quasi-π / 2 phase-step simultaneously. Multi-component phases related to 3D deformation information are extracted by a 90 deg step 4-frame technique from the separated red, green, and blue channels of color images. Six derivative components are further determined based on the retrieval phase maps. Experimental results demonstrate the validity and feasibility of the proposed method.