3D shape measurements using phase-encoded patterns and phase-shifting techniques

A fringe projection method based on the phase-shifting technique for 3D shape measurements is presented. Phase extraction is performed by the phase-shifting technique, while unwrapping is discerned by the phase-encoded patterns. There is no need to take additional projections for phase unwrapping. The fringe patterns used for phase extraction can be directly utilized for unwrapping. Experiments show that absolute phases could be obtained with high reliability.