Spatial Filtering of Optical Images in Acousto-Optic Cells Based on Biaxial Crystal

In this work, for the purpose of spatial filtering of optical images, we propose to use low-selective variants of isotropic light scattering in optically biaxial crystals. The most attention is paid to the study of the structure of the two-dimensional transfer function of acousto-optic filters using such a geometry of light diffraction, and to its evolution occurring with frequency change of ultrasound. It is shown that, depending on the biaxial crystal cut, the above transfer function has either an X-shaped or a U-shaped form, which has no analogues among uniaxial crystals. The possibilities of using the considered acousto-optic filters for visualization of the optical wavefront are examined.