Ultrasonic Diffraction of Light by Short Acoustic Pulses

Abstract

A theoretical analysis of the Raman-Nath diffraction of light by short acoustic pulses has been developed. “Short” means a pulse whose length in the medium is of the order of, or less than, the diameter of the light beam. Expressions are derived that give the angle and time dependence of diffracted intensity for pulse trains as well as single acoustic pulses. With pulse trains, each diffracted order becomes broadened by a “suborder” structure, which may be resolved under appropriate conditions. In the time domain, calculated curves are presented comparing the shape of diffracted light pulses to the originating acoustic pulses.