Diffraction of needle light beams by ultrasonic waves in paratellurite crystals

Bragg diffraction of circularly polarized needle light beams by a slow shear ultrasound wave in paratellurite crystals is studied. It is shown that by changing the cone angle of the Bessel light beam incident on the diaphragm, a high diffraction efficiency of 90 increase in the length of the acousto-optic interaction, the diffraction efficiency of the needle light beams reaches a maximum value at lower ultrasound powers. It is shown that at small cone angles of the light beam, the diffraction efficiency of the needle light beam is comparable to the diffraction efficiency of the Gaussian one.