Optical field control via liquid crystal photoalignment

ABSTRACT

Optical field control of laser beams is realized through photo-aligned liquid crystals. A dynamic micro-lithography system combined with a polarization-sensitive alignment agent is utilized to perform arbitrary fine liquid crystal alignment. Fork gratings are fabricated to generate high quality optical vortices. Forked polarization gratings with space-variant liquid crystal azimuthal orientations are proposed and corresponding optical vortices with arbitrary azimuthal and radial indices are demonstrated in high efficiency. Moreover, Airy masks for polarization selective Airy beam generation and polarization converters suitable for arbitrary vector beams are fabricated. This technology drastically enhances the capability of optical field control.

KEYWORDS:

• Liquid crystals
• photoalignment
• fork gratings
• optical field control

Acknowledgements

The authors are indebted to Prof. V. Chigrinov for his kind support with photoalignment agent and technique. This work was supported by the [National Natural Science Foundation of China] under grants [number 11304151], [number 61490714], [number 61435008] and [number 61575093].