Phase error compensation methods for high-accuracy profile measurement

摘要

In a phase-shifting algorithm-based fringe projection profilometry, the nonlinear intensity response, called the gamma effect, of the projector-camera setup is a major source of error in phase retrieval. This paper proposes two novel, accurate approaches to realize both active and passive phase error compensation based on a universal phase error model which is suitable for a arbitrary phase-shifting step. The experimental results on phase error compensation and profile measurement of standard components verified the validity and accuracy of the two proposed approaches which are robust when faced with changeable measurement conditions.