Formation of probing radiation for investigating a uniaxial x-cut crystal with the help of an aperiodic diffractive axicon

Abstract

The paper presents an experimental study of transformation of a laser beam formed by an aperiodic diffractive axicon (fracxicon) in a lithium niobate x-cut. The beam is shown to undergo astigmatic rhomboidal transformation induced by the crystal birefringence. The output beam intensity distribution is measured at various distances from the crystal. The effects analyzed make it possible to extend the range of measuring thickness or birefringence of solid, liquid or gaseous media with uniaxial optical anisotropy.