The Measurement Method of Flexo-coefficients of Nematic LCs

Abstract

We propose a novel measurement method for flexo-coefficients e₁₁, e₃₃ (splay, bend) by using the HAN (Hybrid Aligned Nematic) type cell. In this method, we calculate numerically the orientational distribution throughout the HAN cell based on the continuum theory taking into account of the flexo-electric effect. The transmittance under the electric field is also calculated. Experimentally the electro-optical characteristics of the HAN cell is measured under the D.C. applied voltage. Then flexo-coefficients can be determined by the fitting procedure.