New bistable liquid-crystal twist cell

Abstract

We have shown experimentally that some cholesteric liquid crystals in cells with parallel or skew director orientations at the two surfaces may be made to have two bistable laminar states that can be switched either way by applying temporary electric potentials between the surfaces. Numerical solutions of the Oseen-Frank equations in the laminar case, augmented with cholesteric twist and electric field terms, confirm the bistability. Numerical solutions of the Leslie-Ericksen hydrodynamic equations in the laminar case, similarly augmented, describe the switching mechanism. We have made and operated several such cells.