DOI: 10.22184/1993-7296.FRos.2023.17.5.394.406

The paper presents the study results of the effect of a biconical axicon, a refractive optical element with two conical surfaces, on illumination by radiation of various polarization states, including inhomogeneous one (with azimuthal and radial polarization). The biconical axicon was previously proposed for converting a beam with circular polarization into a azimuthal polarized beam due to the beam reflection and refraction at the Brewster angle on one conical surface, followed by the beam collimation due to the second conical surface. The polarization transformations performed during diffraction of beams with various polarizations by a biconical axicon are calculated using the finite difference method in the time domain. Based on the numerical simulations, it is shown that the biconical axicon made of K14 glass (with the refractive index n = 1.4958) can be used as a detector for azimuthal and radially polarized beams based on the intensity pattern in one plane.