Interferometric measurement of the magnitude of acoustic transducer motion

Abstract

Experiments have shown that the magnitude of the displacement of excited acoustic transducers can be simply and very accurately measured employing a technique called Speckle Field Interferometry. The application of a specially designed Speckle Field Displacement Interferometer to problems of motion measurement has resulted in the successful quantitative characterization of the behavior of certain transducers. These characterizations are part of a program, which includes holographic interferometry [H. Fein, J. Acoust. Soc. Am. Suppl. 1 73, S24 (1983)], to accurately evaluate the performance of transducer systems and are shown to be of great value in defining actual operating dynamics. Interferometric data, methods, and results are presented.