V.M. Kotov, G.N. Shkerdin, S.V. Averin
In the paper a theoretical model of the acousto-optic (AO) interaction in the gyro tropic anisotropic crystals taking into account both the ellipticity of the crystal eigenmodes and the curvature of the vector waves surfaces is developed. The set of differential equations is derivate, the peculiarities of the single phonon and two phonon Bragg diffractions with the using of AO properties of the paratellurite crystal are investigated. Two-dimensional transfer functions of the diffracted orders are obtained and investigated. These functions allow explaining the forming of the two-dimensional contour of the optical image during its optical Fourier processing. In particular, it is obtained the two-dimensional edge enhancement of the images in the form of the circle and rectangle with the using of the transfer function of the second order as the spatial frequency filter. For the checking of the obtained results the experiment was fulfilled in which the optical Fourier processing of the images in the form of the circle and rectangle was realized with the using of AO cell from paratellurite served as the filter of the spatial frequencies. The fulfilled experiments totally confirmed the theoretical conclusions.