Abstract
A theoretical investigation of mixed isotropic-anisotropic Bragg diffraction of light by ultrasound is presented. This case of acousto-optic interaction appears as isotropic and anisotropic scattering taking place simultaneously, and is typical only of a birefringent crystal. The problem of light diffraction is examined under the approximation of plane waves using coupled waves theory. In the case of absolute Bragg matching, an analytical solution of the diffraction problem has been obtained. The mixed scattering has also been considered in the case of weak violation of phase synchronism conditions. Results of numerical solutions with respect to the light intensities of the diffracted beams are presented and the characteristic features of the mixed interaction are described.