Fully symmetric diffraction-interference beam shaper for radially polarized light on a 1530-nm wavelength

A completely symmetrical scheme of a shaper of cylindrical vector beams is proposed in which two diffractive axicons and an interference polarizer placed in-between form a sandwich structure of the smallest possible thickness. The design and experimental study of an interference polarizer for generating the radially polarized radiation at a 1530-nm wavelength is carried out. A pair of amplitude diffractive axicons with a period of 3.62 $\mu m$ to provide the diffraction angle of 24.5$^\circ$ required for generating radial polarization is fabricated. The transformation of a circularly polarized beam into a radially polarized vortex beam is experimentally demonstrated.