Liquid crystal handedness switch and color filter

摘要

This invention provides a liquid crystal polarization handedness switch, and optical devices employing the handedness switch in conjunction with optical elements which are sensitive to the handedness of incident light. The handedness switch receives unpolarized light and converts it into circularly polarized light with switchable handedness. In combination with cholesteric circular polarizers, switchable color filters are provided. The color filters of this invention include the analogous x-y polarization switch combined with colored partial polarizers. The liquid crystals employed in the color filter of this invention can include SmC*, SmA*, antiferroelectric, DHF, achiral ferroelectric and twisted nematic liquid crystals.