Abstract

Most of the electrical signals applied to the transducer of a acousto-optic (AO) device are not simply cw signals. For the purpose of applications, it is necessary to investigate the interaction between optical beams and multi-tone-modulated sound waves. Starting from the coupled wave equations for the optical fields in the AO sound cell, with the sound field as a multitone amplitude-modulated signals, a Fourier-transform technique is used to express the interactions in spatial frequency domain. A number of the coupled differential equations, which describe the interactions between the optical fields and sound fields of each side band, can be obtained. Due to the fact that there is no analytic solution for these coupled equations, a well-known numerical technique, namely, the Runge-Kutta method, is employed to solve the equations. To check the formulation, Bragg diffraction of a Gaussian light beam is considered. Detailed numerical simulations, comprising Fourier transforming the input beams profile to calculate the spectra of the scattered beams, and hence their profiles in space using the inverse transform are presented.

© 1990 Optical Society of America