Flat cholesteric liquid crystal polymeric lens with low f-number

Opt Express. 2020 Feb 17;28(4):5875-5882. doi: 10.1364/OE.387942.

Abstract

We use a simple photoalignment method to fabricate four reflective cholesteric liquid crystal (CLC) polymeric lenses with diameter D=2.45 cm and low f-numbers (f/2, f/0.9, f/0.45, f/0.33) at 550 nm. Such a flat CLC lens can be converging or diverging, depending on the handedness and direction of the incident light. Our CLC lenses can achieve ∼85% diffraction efficiency for a designated polarization state and manifest decent imaging ability.