Backward lateral displacement of an ultrasonic beam reflected from a liquid-solid interface

Abstract

Tamir and Bettoni [J. Opt. Soc. Am. 61, 1397 (1971)] have predicted that light reflected from a dielectric interface can undergo a backward beam shift under special conditions. When applied to the reflection of an ultrasonic wave from a liquid-solid interface, this means that a negative “Schoch displacement” exists. Such a reverse lateral displacement can be obtained by reflection from an interface formed into a periodic structure. Using a new schlieren system with a unique goniometer, we have been able to photograph the backward displacement of an ultrasonic wave at a water-brass grating interface and thus demonstrate the basic validity of this aspect of the Tamir and Bertoni theory. [Research supported by the Office of Naval Research.]