Absolute phase retrieval for 3D shape measurement by Fourier transform method

Abstract

Accurate 3D shape measurement via fringe analysis methods requires the determination of the absolute phase map of the object. In this paper, we present a novel method for absolute phase retrieval developed for use with the Fourier transform method for fringe analysis. A cross-shaped marker is embedded in the fringe pattern that is projected to the object. The position of the marker in the captured fringe image is detected and later used in calculating the absolute phase map. For phase analysis of the fringe image, the marker is removed and the sinusoidal intensity distribution of the fringe pattern is restored before the Fourier transform method is applied. This paper focuses on the concept of absolute phase retrieval from a single fringe pattern as well as techniques on marker detection and removal. Experimental results on absolute phase retrieval and 3D reconstruction are also presented to show the feasibility of the proposed method.