Beam shaping via photopatterned liquid crystals

ABSTRACT

Due to the fantastic properties and diverse applications of specific beams, optical beam shaping has attracted intensive attentions recently. Generally, these beams can be converted from Gaussian beams via particular spatial amplitude or phase control. In this work, we present a liquid crystal photopatterning technique based on dynamic microlithography with a polarisation-sensitive photoalignment agent. This technique enables the accurate, arbitrary and reconfigurable azimuthal angle control of liquid crystals, thus providing a powerful approach for the manipulation of light. By this means, the tailoring of arbitrary fine microstructures with binary or continuously space-variant liquid crystal azimuthal orientations are demonstrated. We briefly review our recent work on some specially designed patterns and corresponding specific optical fields. High-quality vortex beams, vector beams and Airy beams are generated with unprecedented flexibility in the design and control of light wavefront. Besides high efficiency, good electrical switchability and broad wavelength tolerance, the proposed devices also exhibit merits of compact size, low cost, dynamic mode conversion and polarisation controllable energy distribution, and are available for short pulse and intense light modulation. This work may pave a bright way towards beam shaping and bring new possibilities for the design of novel advanced liquid crystal photonic devices.