LAUSR

A dual-stimuli polarizer-free dye-doped liquid crystal (LC) dimmer is demonstrated. The LC composition consists of photo-stable chiral agent, photosensitive azobenzene, and dichroic dye in a nematic host with positive dielectric anisotropy. Upon UV exposure, the LC directors and dye molecules turn from initially vertical alignment (high transmittance state) to twisted fingerprint structure (low transmittance state). The reversal process is accelerated by combining a longitudinal electric field to unwind the LC directors from twisted fingerprint to homeotropic state, and a red light to transform the cis azobenzene back to trans. This device can be used as a smart dimmer to enhance the ambient contrast ratio for augmented reality displays.