Holographic interferometry has been the most immediate, significant application of laser holography. For the first time, optical interferometric measurements can be made on non-optical surfaces; such as castings, pipes, panels, composites, etc., as well as through diffusely illuminated transparent scenes. Like classical interferometry, holographic interferometric measurements are sensitive to path changes down to one tenth of a wavelength of light (0.07 micron or 3 microinches). The technique has made available a completely new method of non-destructive testing: automobile tire testing, testing of adhesive bonds, pressure vessels, microwave antenna testing, the determination of resonant frequencies of mechanical structures, transient deformation of surfaces, and the study of aerodynamic phenomena.

Date Published: 1 August 1972
PDF: 14 pages
Proc. SPIE 0029, Imaging Techniques for Testing and Inspection, (1 August 1972); doi: 10.1117/12.978156

Published in SPIE Proceedings Vol. 0029:
Imaging Techniques for Testing and Inspection
John C. Urbach; Byron B. Brenden; Robert Apprahamian, Editor(s)