Vortex retarders produced from photo-aligned liquid crystal polymers.

We present developments using photo-aligned liquid crystal polymers for creating vortex retarders, halfwave retarders with a continuously variable fast axis. Polarization properties of components designed to create different polarization vortex modes are presented. We assess the viability of these components using the theoretical and experimental point spread functions and optical transfer functions in Mueller matrix format, point spread matrix (PSM) and optical transfer matrix (OTM). The measured PSM and OTM of these components in an optical system is very close to the theoretically predicted values thus showing that these components should provide excellent performance in applications utilizing polarized optical vortices. The impact of aberrations and of vortex retarder misalignment on the PSM and OTM are presented.