Abstract

There is a need in the manufacturing sector to rapidly and nondestructively inspect components under harsh in-factory and field-testing conditions. Laser ultrasonics [1] offers a technique for inspection without direct contacting, resulting in a nondestructive, remote diagnostic. Conventional interferometric and heterodyne receivers are unable to compensate for workpiece vibrations and/or wavefront distortions, relative platform motion, and local turbulence. Fabry-Perot-based systems [1] have limited application due to complexity and cost. Compensated interferometers employing phase conjugation [2] or wavefront-matching [3] typically lack the speed-of-response to function in the factory, especially in the case of inspection of rapidly moving components on an assembly line or in the case of raster scanning a workpiece.

© 1995 Optical Society of America