Reflective Display Associated with In-Plane Rotation of Nematic Liquid Crystal

We have fabricated a novel reflective nematic liquid-crystal cell driven by a fringe field. In the absence of an electric field, the liquid-crystal molecule is homogeneously aligned and when a fringe field induced by interdigital electrodes is applied, liquid-crystal molecules rotate in plane in the entire whole area. A conventional in-plane switching (IPS) cell was impossible for application to a reflective system due to its low aperture ratio. However, a newly designed fringe-field switching (FFS) cell is possible due to its high transmittance. Furthermore it exhibits a wide viewing angle intrinsically owing to the in-plane rotation of the liquid-crystal director. Several reflective systems with either two polarizers or one polarizer with a quarter-wave retardation film are possible. In this study, we investigate the switching principle of each system and compare their electrooptic characteristics by simulation and experiment.