Switching characteristics of liquid crystal filled polymer diffractive optical elements

摘要

The aim of this work was to produce switcheable optical elements that could be produced at low cost. Liquid Crystal Filled Polymer Structure (LiCFiPS) devices consist of a polymer structure, which performs the desired spatial phase modulation of the incident light, filled with liquid crystal to permit modulation of this optical function. Potentially these device may be fabricated at very low cost using established polymer processing techniques. Devices incorporating a complex polymer structures as the diffractive element will inevitably have liquid crystal aligned at varying orientations to the surface. Devices with the liquid crystal aligned perpendicular to the grating lines tend to show liquid crystal defects. Suppression of these defects is important for good optical quality. Characterisation of devices has shown that driving the devices at moderately high voltages will suppress the defect offering a route to improved quality of electro-optic switching. While such devices might not offer the ultimate versatility of matrix addressed SLM type devices they do offer electronic control of diffractive optical devices at very low cost.