POLYMER DISPERSED LIQUID-CRYSTAL FILMS WITH MEMORY CHARACTERISTICS

Polymer dispersed liquid crystal (PDLC) films with memory electrooptical characteristics were fabricated. The approach made use of phase transition characteristics of smectic liquid crystals. If a smectic is cooled from the nematic to the smectic state in the presence of an electric field, one obtains an aligned smectic. This structure yields a transparent state. However, if the material is cooled in the absence of the field, it adopts a focal conic texture which yields a light-scattering state. The fabrication of these devices, together with their measured electrooptical characteristics, is reported.