Phase error model and compensation method for reflectivity and distance discontinuities in fringe projection profilometry.

Abstract

Phase shifting fringe projection profilometry is a widely used optical 3D surface measurement method due to its high resolution, high speed, and full-field inspection. However, the measurement accuracy decreases in regions with a reflectivity or distance discontinuity. To this end, first, a general continuous quasi-one-dimensional phase error model is proposed for discontinuity representation. Second, the discontinuities are further divided into degenerate and nondegenerate discontinuities to improve the computational speed. Third, a phase error compensation algorithm is proposed with a parameter estimation method to improve the measurement accuracy. Simulations and experiments demonstrate that the proposed methods are effective.