Share Email Print

Proceedings Paper

Two-step temporal phase unwrapping in profilometry
Author(s): Yves Surrel
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

This paper proposes a fast phase unwrapping procedure capable of dealing with arbitrarily large phase discontinuities. Such discontinuities may be present in the phase maps obtained with the technique of profilometry by fringe projection, when the studied object presents sharp height discontinuities. In our procedure, two images are taken with high frequency projected fringes, so that spatial phase-stepping is possible. The algorithm sued eliminates the harmonics up to order 7. The fringe pitch is slightly varied between the two acquisitions, and the difference between the two obtained phase maps yields a slowing varying phase map which enables unwrapping, as it gives low frequency extra information.As compared to other proposed procedures, the present one allows to keep the high sensitivity associated with high frequency fringes, together with the large dynamic range resulting from the possibility to unwrap the phase successfully. Also, the number of frames required is less than what is needed by other techniques.

Paper Details

Date Published: 17 September 1997
PDF: 12 pages
Proc. SPIE 3098, Optical Inspection and Micromeasurements II, (17 September 1997); doi: 10.1117/12.281170
Show Author Affiliations
Yves Surrel, Ecole des Mines de Saint-Etienne (France)

Published in SPIE Proceedings Vol. 3098:
Optical Inspection and Micromeasurements II
Christophe Gorecki, Editor(s)

© SPIE. Terms of Use
Back to Top