Phase unwrapping of fringe images for dynamic 3D measurements without additional pattern projection

Fringe projection is an established method for contactless measurement of 3D object structure. Adversely, the coding of fringe projection is ambiguous. To determine object points with absolute position in 3D space, this coding has to be unique. We propose a novel approach of phase unwrapping without using additional pattern projection. Based on a stereo camera setup, an image segmentation of each view in areas without height jumps larger than a fringe period is necessary. Within these segments, phase unwrapping is potentially without error. Alignment of phase maps between the two views is realized by an identification process of one correspondence point.