Deformation Pattern of Twisted Nematic Liquid Crystal Layers in an Electric Field

Abstract

Abstract At rest between two metallized glass plates a nematic liquid shows a screw-like deformation pattern if one turns the plates by an angle ωm around an axis perpendicular to the plates. If a voltage U is applied, the molecules are tilted with respect to the electric field when U exceeds a threshold voltage. With increasing amount of twist ωm the maximum angle of tilt γ m increases to almost π/2 even in a weak field. Numerical results are given for the Schadt-Helfrich-cell, i.e. ωmλπ/2. The effect of piezc-electricity on deformation in a Schadt-Helfrich-cell is discussed.