Holographically-formed polymer dispersed liquid crystals with multiple gratings

摘要

A multicolored reflection liquid crystal display device includes a pair of substrates having a reflective holographic polymer dispersed liquid crystal (H-PDLC) film disposed therebetween. The H-PDLC film contains at least two different reflection gratings capable of reflecting two different wavelengths of light. A multicolored reflection H-PDLC is obtained by simultaneously illuminating a plurality of regions of a film comprised of a mixture of a liquid crystal and a photo-polymerizable monomer with a plurality of holographic light patterns capable of providing liquid crystal layers of different spacings so as to obtain different reflection gratings in each of the regions. A mask is placed between each of the laser light beams and the film to form a pattern of light and dark regions on the film. Each mask is positioned such that at least one light region of a first beam pair coincides with at least one dark region of a second beam pair within the film. A multiple grating liquid crystal display device including an H-PDLC film having a first region comprising liquid crystal and matrix polymer layers forming a transmission grating and a second region comprising liquid crystal and matrix polymer layers forming a reflection grating capable of reflecting a preselected wavelength of light also is described.