Acoustic beams structure in crystals and its influence on acousto-optic interaction characteristics

An original solution of acoustic beams diffraction in anisotropic media based on application of the spatial Fourier transform method is presented. The solution makes it possible to calculate the acoustic beam structure for any directions of acoustic wave propagation in crystals and for any distances from a transducer. Detailed computations are fulfilled for a paratellurite single crystal which is distinguished by extremely strong anisotropy of acoustic properties. Ray spectra for different directions of ultrasound propagation are first calculated. Effects of beam focusing, defocusing and autocollimation caused by acoustic anisotropy are analyzed. The influence of amplitude and phase structure of real acoustic beams on AO characteristics is studied as well.