Electrically Switchable Color Changes in Lying Helix Cholesteric Liquid Crystals

Abstract

Cholesteric liquid crystal (CLC) is a one-dimensional photonic material with a self-assembled helical structure of either a right-handed or left-handed circular rotation of the nematic liquid crystal director along a helical axis. Previously we reported dynamic EO response in polymer stabilized cholesteric liquid crystals (PSCLCs) prepared with negative dielectric anisotropy (Δε < 0) nematic liquid crystal hosts, including DC field induced bandwidth broadening [1–4], red shifting tuning [5,6], blue shifting tuning [7] and scattering switching [8] responses. This dynamic EO response is explained by the electromechanical deformation of the polymer network directly affecting the pitch of the CLC.