Optically reconfigurable color change in chiral nematic liquid crystals based on indolylfulgide chiral dopants

摘要

Stimuli-directed changes in the coloration of chiral nematic liquid crystal devices are in nearly all cases color-restoring upon removal of the input stimulus. This work employs photoresponsive indolylfulgide chiral dopants to generate optically reconfigurable but color-stable reflectivity when formulated with a nematic liquid crystal host to form a chiral nematic mesophase. The optically-directed color change of the chiral nematic material system to UV and blue irradiation is examined as a function of concentration and light intensity. The temporal stability of the reflection notch at arbitrary spectral positions is presented - confirming that long-lasting, optically reconfigurable color changes are obtainable in this material system. The optically reconfigurable color-stable changes in reflection color could be useful as optical filters, smart textiles, or active camouflage.