Application of A Phase Unwrapping Method in Reverse Engineering

A new unwrapping method combined with phase shift processing and gray-coded light is discussed, and also the saltation of the phase is avoided. Firstly according to the four-step phase-shift method, a series of gratings constructed are projected on the surface of the object, and the distorted grating images are collected into the computer by the CCD camera ,then the phase collapsed in the range [-π,π] will be obtained. Secondly a series of gray-coded right are projected on the same area, and the period distribution will be got. Finally the phase and the period will be combined with, and the true, exact phase will be obtained. Experiments proved that 3D scan system can get satisfied result by using the method.