High-speed 3-D shape measurement based on digital fringe projection

TLDR

The technique projects a computer‑generated color fringe pattern with 120° phase shifts between RGB channels via a DMD‑based projector, captures the resulting gray‑scale fringe patterns with a synchronized CCD camera, and reconstructs the 3‑D surface using phase‑wrapping, unwrapping, and phase‑coordinate conversion algorithms. Experimental results demonstrate the feasibility of this method for high‑speed 3‑D shape measurement, achieving potential speeds up to 100 Hz. © 2003 Society of Photo‑Optical Instrumentation Engineers; DOI: 10.1117/1.1525272.

Abstract

A high-speed 3-D shape measurement technique based on digital fringe projection has been developed and experimented. This technique uses a computer-generated color fringe pattern whose red, green, and blue channels are sinusoidal fringe patterns with a 120-deg phase shift between neighboring channels. When this color fringe pat- tern is sent to a digital-micromirror-device (DMD) based video projector with no color filter, three gray-scale fringe patterns are repeatedly pro- jected to an object surface in sequence with a cycle time of approxi- mately 10 ms. The three phase-shifted fringe patterns deformed by the object surface are captured by a CCD camera with proper synchroniza- tion between the camera and the projector. The 3-D shape of the object surface is reconstructed by using a phase wrapping and unwrapping algorithm and a phase-coordinate conversion algorithm. Experimental results demonstrated the feasibility of this technique for high-speed 3-D shape measurement with a potential measurement speed up to 100 Hz. © 2003 Society of Photo-Optical Instrumentation Engineers. (DOI: 10.1117/1.1525272) Subject terms: fringe projection; phase shifting; digital micromirror device; 3-D shape measurement.