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Abstract
Polymer dispersed cholesteric liquid crystal (PDCLC) films have been fabricated via the Polymerization-Induced Phase Separation (PIPS) technique, E48:TM74A:PMMA PDCLCs, with LC:PMMA ratio of 80:20 and varying E48:TM74A weight ratio, have been characterized for their electro-optic properties. The PDCLC films have been UV-cured (λ = 365 nm) at various curing times. Transmittance measurements, conducted using a linear optics set-up with a He-Ne laser (λ = 632.8 nm) as probe beam while subjected to varying voltage, showed that 10μm-thick films UV-cured for 3 hours exhibited the best electro-optic response among all the samples. The use of cholesterics in PDCLCs resulted to a lower off-state transmittance and higher contrast ratio compared to purely nematic PDLCs. As a consequence, however, the threshold and driving voltages are increased for PDCLCs.