Exponential fringe projection for alleviating phase error caused by gamma distortion based on principal component analysis

Fringe projection profilometry is commonly used for three-dimensional (3-D) shape measurement. The gamma effect caused by nonlinear intensity response of projector-camera system makes ideal sinusoidal waveforms nonsinusoidal, leading to phase and 3-D shape errors. The existing phase-error compensation methods or gamma correction methods are complicated and time-consuming. An exponential fringe projection method is proposed based on principal component analysis to alleviate phase error without requiring any complicated prior and post data. The experimental results demonstrate that the proposed method decreases the phase error effectively with high quality in the measured surfaces and needs low computational cost by comparing with the existing state-of-the-art methods.