Patent ID: 7812919
Filing Date: 2010-10-12
Classification: G02F

Abstract:
1. A method comprising: providing a pair of opposed substrates to form a cell; providing conductive electrodes disposed on facing surfaces of said substrates; providing alignment layers on facing surfaces of the conductive electrodes; disposing a material comprising a cholesteric liquid crystal into said cell, the cholesteric liquid crystal having a cholesteric helix at zero bias effective to define a Bragg reflective wavelength, wherein the cholesteric liquid crystal has helixes aligned perpendicular to the substrates at zero applied voltage; and selectively changing said Bragg reflective wavelength amongst at least four different selectable Bragg reflective wavelengths by applying a selected one of at least four different corresponding voltages to said cell via said conductive electrodes, the applied voltage being selected to decrease the Bragg reflective wavelength by a selected amount.