Reconstructing the Poynting vector skew angle and wave-front of optical vortex beams via two-channel moir\'e deflectometery

A novel approach based on the two-channel moir'e deflectometry has been used to measure both wave-front and transverse component of the Poynting vector of an optical vortex beam. Generated vortex beam by the q-plate, an inhomogeneous liquid crystal cell, has been analyzed with such technique. The measured topological charge of generated beams are in an excellent agreement with theoretical prediction.