Digital image correlation assisted absolute phase unwrapping (2022)
/Y-H. Liao, M. Xu, and S. Zhang, "Digital image correlation assisted absolute phase unwrapping," Optics Express 30(18), 33022-33034 (2022); doi: 10.1364/OE.470704
Abstract
This paper presents an absolute phase unwrapping method for high-speed three-dimensional (3D) shape measurement. This method uses three phase-shifted patterns and one binary random pattern on a single-camera, single-projector structured light system. We calculate the wrapped phase from phase-shifted images and determine the coarse correspondence through the digital image correlation (DIC) between the captured binary random pattern of the object and the pre-captured binary random pattern of a flat surface. We then developed a computational framework to determine fringe order number pixel by pixel using the coarse correspondence information. Since only one additional pattern is used, the proposed method can be used for high-speed 3D shape measurement. Experimental results successfully demonstrated that the proposed method can achieve high-speed and high-quality measurement of complex scenes.