Abstract: The present invention relates to a display device based on liquid crystals, comprising a nematic liquid-crystal material (10) with positive dielectric anisotropy sandwiched between two transparent confinement plates (20, 30) each provided with transparent electrodes (22, 32), characterized in that at least one of the plates, (30), defines a quasi-bistable anchoring and in that it is provided with main electrical supply means (40) suitable for applying a temporary electric field to the liquid-crystal material (10) capable of breaking the anchoring on the aforementioned plate (30) and subsequently allowing, due to the effect of hydrodynamic instabilities, various localized orientations of the liquid-crystal molecules (10) corresponding to the preferred orientations of the quasi-bistable anchoring.

Abstract: A liquid crystal device for continuous rotation of the selective polarization of monochromatic light is provided by a cholesteric mixture with positive dielectric anisotrophy contained between a pair of glass plates which are conductive on the surface in contact with the mixture and have received a surface treatment to provide planar orientation for the mixture. A voltage is applied between the two glass plates and an input light polarizer is applied to one of the two glass plates. The device preferably uses a cholesteric mixture comprising cholesteryl chloride (31.2%), cholesteryl oleyl carbonate (47.7%) and cholesteryl nonanoate (21.1%) and is advantageously employed in laboratory polarization rotators and colored display units.