Wrap reduction algorithm for fringe projection profilometry

Abstract

Carrier removal has been typically associated with wrap reduction, and its application has strongly been recommended as a previous step to phase unwrapping. In general, the carrier signal contributes to an increase of the number of wraps, and its removal leads to a reduction of the number of phase inconsistencies, having a positive impact on the subsequent unwrapping operation. In this paper, we show that phase wrap reduction can be better tackled by other alternative and more effective methods that exploit local information and attempt to also remove the signal component associated with the object’s surface. The results are analyzed on a series of real fringe patterns and confirm the better performance of the proposed method, which leads to signals with a lesser number of wraps than by just removing the carrier.