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.