Acousto-Optic Control of Bessel-like Beam Parameters in the Far Zone with the Use of Uniaxial TeO2 and NaBi(MoO4)2 Crystals

Features of the Bragg diffraction of annular light beams on a longitudinal ultrasound wave propagating along optical axis of TeO
2
and $\mathrm{NaBi}\left(\mathrm{MoO}_{4}\right)$ 2 crystals are theoretically and experimentally studied. It is shown that the diffracted beam in far zone is transformed into a Bessel-like beam containing an intense central maximum and several low-intensity lateral rings. The dependence of axial intensity of such small-ring beams, as well as their spatial transverse structure on the longitudinal coordinate at large distances, is investigated. The obtained results are perspective for the development of methods for modulation and control of radiation parameters in wireless optical communication systems.