Phase unwrapping errors correction for phase-encoding based on fringe projection profilometry

Phase-encoding method is a phase unwrapping method commonly used in the fringe projection technology. However, due to the influence of the random noises, image sampling and system defocusing, it is prone to break the corresponding relation between the fringe order and the wrapped phase, which may cause the phase unwrapping errors. According to its distribution characteristics, a phase unwrapping errors correction method with an additional binary fringe was proposed. The half-period dislocation was existed between the codewords of the binary fringe and the phase-encoding fringe, which made the calculated two groups of fringe order values complementary, and the phase unwrapping errors could be effectively eliminated by using the complementary. Both simulation and experimental results show that the proposed method can accurately recover the absolute phase of the measured objects, which has higher reliability.