An Anti-saturation phase retrieval algorithm based on optimal composite fringe patterns for 3D measurement with shiny surface

Abstract

Three-dimensional (3D) measurement of shiny surfaces poses a challenge to the structure light method due to camera saturation caused by the reflective light. Addressing this problem, we propose an anti-saturation retrieval algorithm based on optimal composite fringe patterns. Based on the generalized expression of composite phase-shifting profilometry, we derive a complete phase error model, determine the best phase-shifting ratio theoretically, and finalize the optimal composite fringe pattern. Then, considering the phase retrieving problem occurred in the saturated regions, we present a novel anti-saturation retrieval algorithm by introducing a rejection coefficient, and accurately retrieve the phases of saturated region only with unsaturated values. Experimental results demonstrate that our method possesses a strong anti-saturation ability for shiny surface measurement with no need of adjusting camera exposure or projector brightness.