Refractive-index matching between liquid crystals and photopolymers

Refractive indices of two photocurable polymers, NOA65 and NOA81 (Norland Optical Adhesive), and two series of Merck liquid crystals, E-series (E44, E48, and E7) and BL-series (BL038, BL003 and BL006), and two UCF high-birefringence liquid-crystal mixtures were measured using an Abbe refractometer in the visible spectral region and 15-55 degrees C temperature range. Some liquid crystals have excellent index matching with NOA65 in the red, while some fit better in the blue spectral region. To validate this index-matching property found in the material level, we prepared some polymer-dispersed liquid-crystal devices. Good correlations between material and device performances are obtained.