Application of Holographic Interferometry to Analysis Of Sinusoidally-Excited Acoustic Transducers

摘要

An application of optical holography known as 'Holographic Interferometry' has been developed which enables experimentalists either to measure deformations of a few microns in loaded mechanical systems or to examine relative displacements in sinusoidally-vibrating systems. The fundamental theory of holography and four techniques for holographic interferometry are described in this report. A system constructed to record interferograms of acoustic transducers operating either in air or submerged in water is discussed and some results of examining a sinusoidally-excited 7-inch permanent-magnet loudspeaker with interferograms are considered. (Author)