POLYMER-DISPERSED LIQUID-CRYSTAL THIN-FILMS FOR OPTICAL-PROCESSING

A shape-controlled bistable hysteresis is observed for thin polymer di spersed liquid crystal films when inserted in feedback systems where t he applied voltage depends on the intensity of the light transmitted b y the film. A control of the hysteresis width is possible by acting on the parameters of the feedback circuit. The possibility of obtaining bistable regions of different width can be very useful in view of the application of PDLC as optic memory elements or binary data transmissi on devices. An investigation on the use of these films as optical swit ches for fiber interconnects is also performed and the preliminary res ults are reported. Technical improvements are suggested in order to in crease the on/off contrast ratio of the switching behavior.