Light-rewritable geometric phase and reflectance modulations enabled by pattern-aligned photoresponsive liquid crystal superstructures

ABSTRACT

We propose a universal method of fabricating and operating a multifunctional diffractive optical element (DOE) with light-rewritable geometric phase and reflectance modulations enabled by pattern-aligned photoresponsive liquid crystal superstructures via manipulating the photoalignment layers as well as the phototunable helical pitch of the cholesteric liquid crystal (CLC) under different light stimuli, i.e. ultraviolet and visible (green) lights. The diffractive behaviour of the fabricated CLC DOE is simultaneously governed by the geometric phase induced by the pattern-aligned CLC and the reflectance (amplitude) modulation attributed to the helical pitch manipulation, endowing the proposed DOE with versatile practical light-controllable characteristics and outstanding performance.

Graphical abstract

KEYWORDS:

• Cholesteric liquid crystal
• light-reconfigurable
• wavelength-selective
• multifunctional
• diffractive optical element

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work is sponsored by the National Natural Science Foundation of China (NSFC) (Nos. 61435008, 61822504, 61705067, 51873060 and 61575063), the Shanghai Pujiang Program (No. 16PJ1402200) and the Shanghai Rising-Star Program (No. 17QA1401100).