Gamma Correction Method Based on Phase-shifting Keying

Phase Measurement Profilometry (PMP) plays an important role in reconstructing three-dimensional surface of objects. However, the reconstructed profile error is always resulted from gamma distortion. In this paper, a simple and efficient method is proposed to solve the gamma distortion. Firstly, the fringe mapping is analyzed via Gamma distortion model. Then, based on the phase-shifting keying (PSK), two sets of phase-shifting patterns of different phase are generated separately. It shows that the effect of the second harmonic can be eliminated by adding the corresponding captured fringe patterns. Finally, the accurate wrapped phase can be obtained. The proposed method does not require the phase error compensation and the pre-calibrated procedure. Experiments show that the proposed method has good performance in terms of accuracy and correction effect.