The Measurement of 3D Object Shape Based on Fourier Transform Profilometry

Abstract

In this paper, we present an optical profilometric technique for 3D shape measurement--Fourier Transform Profilometry (FTP). In contrast to other optical techniques, the grating pattern will in its spatial frequency fields as well as in its space-signal fields which projected onto the object surface and was Fourier-transformed and processed. This technique only requires a single fringe pattern up to no more than two to reproduce 3D object shape. FTP has a much higher sensitivity to the fringe quality than other techniques. We design a system which has a high-resolution system composed of a video projector and a digital camera. A fringe pattern of programming by computer is projected onto the free surface and its diagram is recorded by the camera. The deformed fringe pattern arising from the surface deformations is later compared to the unreformed (reference) one, leading to a phase map from which the free surface can be reconstructed after some series of processes.