Performance Comparison of Surface Recovering Algorithms used in Fringe Projection Profilometry

Profilometry by fringe projection is an optical metrology technique implemented projecting a sinusoidal grating onto a three-dimensional surface, where the resulting deformed grating image represents the object’s height distribution modulated in phase. Fringe projection can be implemented as a phase shifting process or as a one-frame method. In this work, both approaches are compared using a correlation and a Fourier transform based algorithm for phase extraction. As a first step of the surface recovering process, a wrapped phase image is obtained. Therefore, a correction is applied by means of a phase unwrapping algorithm, obtaining a continuous phase distribution. The results show that the phase shifting approach returns a phase distribution with higher resolution and less noise than the one-frame approach.