high concentration of nematic liquid crystal in the film layer is required also fast gelation of the curing monomer results in small liquid crystal domains for this embodiment a commercially available norland resin noa 65 was used of course similar polymer resins could be used to practice this invention such as sam 114 merck mxm 035 merck pn 393 merck or reactive mesogenes like rm 1 rm 82 rm 84 all made by merck the elastic nature of the selected polymer is favorable for lowering the surface interaction with the nematic material the curing rate of the norland polymer is high enough to form the necessary liquid crystal morphology the choice of the liquid crystal plays a very important role in the electro optical performance of the birefringent cell 10 high u03b4n and u03b4 u03b5 are both important parameters in the choice of liquid crystal material as they result in higher birefringence change and lower applied switching fields the following materials are commercially available from merck the e and bl type materials are composed of mixtures of cyanobiphenyls and higher aromatic homologues their u03b4n varies from 0 21 to 0 28 and u03b4 u03b5 varies from about 13 to 18 the main advantage of the cyanobiphenyl liquid crystals is their compatibility with norland based monomers merck also supplies the so called tl compounds that are composed of mixtures of chloro and fluoro substituted mesogens the tl series are characterized by high environmental stability high resistivity high voltage holding ratio and low switching fields the n i transition temperature of the liquid crystals is also important in the choice of the liquid crystal this is important for devices that may operate at higher temperatures liquid.