The development of Electronic Speckle Pattern Interferometry (ESPI) for the analysis of in-plane strain measurement on rotating structures has been proceeding at The City University. ESPI is a technique which not only possesses the accuracy of holographic interferometry but with the ease of electronic processing of television pictures avoids the delays involved in normal photographic techniques. Using a pulsed laser to overcome the rigorous stability requirements of conventional holography gives this method the potential of an experimental technique which may be used under service environmental conditions, with little or no shut-down of costly production-line plant. The experimental results achieved so far show reasonable fringe contrast for in-plane displacements over a wide range of tangential velocities up to nearly 5 ms^-1. Both rotational speed dependent strains and strains independent of speed have been measured in the laboratory with repeatability.

Date Published: 26 October 1983
PDF: 4 pages
Proc. SPIE 0398, Industrial Applications of Laser Technology, (26 October 1983); doi: 10.1117/12.935379

Published in SPIE Proceedings Vol. 0398:
Industrial Applications of Laser Technology
William F. Fagan, Editor(s)