Acoustic field structure simulation in quasi-collinear acousto-optic cells with ultrasound beam reflection

•The bulk acoustic wave reflection from the crystal face influence on its structure.•The TeO2 acoustic anisotropy influence before the ultrasound beam reflection is low.•Low anisotropy before the reflection allows to form fairly homogeneous acoustic field. Ultrasound wave reflection from one of the crystal faces is the convenient way to arouse the acoustic beam with a desired propagation direction in acousto-optic cells with collinear and quasi-collinear interaction geometries. The reflection process effects on the ultrasound field amplitude and phase structure. The method to simulate the reflected finite ultrasound beam structure in the case of acoustically anisotropic media is presented in this paper. The investigation is carried on the example of two quasi-collinear acousto-optic cells fabricated on the base of tellurium dioxide crystal. The cells have special geometry that allows to obtain extremely long acousto-optic interaction length and to achieve unprecedented spectral resolution. The influence of reflection process in the acousto-optic diffraction characteristics was also examined.