Dichroic dye containing polymer-dispersed liquid crystal films

Polymer dispersed liquid crystal (PDLC) devices modulate light through electrically controlled light scattering. Colored PDLCs are formed by incorporation ofdichroic dyes. The efficiency ofthe dichroic dye, PDLC films depend on the scattering efficiency of the films, the dichroic ratio of the dichroic dye, the order parameter ofthe dichroic dye in the liquid crystal used, and the fraction ofdye dissolved in the liquid crystal droplets. The efficiency of these films can be measured using a UV/visible spectrometer. Incorporation of dichroic dye in the PDLC film increases the refractive indices of the liquid crystal droplet affecting the scattering efficiency ofthe PDLC film.