Novel cholesteric liquid crystal films creating angle insensitive reflective colors

Abstract

We have developed novel cholesteric liquid crystal (Ch-LC) films creating angle insensitive reflective colors. The wavy alignment formed by rapid change of the helical twisting power (HTP) enables the suppression of color shift with different incident angles of light. These films open the door to create various decorative films for innovative applications.

Beyond Color Boundaries: Pioneering Developments in Cholesteric Liquid Crystal Photonic Actuators

“…The use of chiral liquid crystals with thermally induced inversion of helicity has also been demonstrated to achieve this [25]. By adjusting the type and mass ratio of the chiral agent, the pitch (p) as well as the chirality of the helical photonic structure can be adjusted, as given by the following equation [26]:…”

“…The use of chiral liquid crystals with thermally induced inversion of helicity has also been demonstrated to achieve this [ 25 ]. By adjusting the type and mass ratio of the chiral agent, the pitch ( ) as well as the chirality of the helical photonic structure can be adjusted, as given by the following equation [ 26 ]: where is the doping concentration of the chiral agent in the system, and helical twisting power ( ) describes the magnitude of the spinning ability of the chiral dopant for a particular liquid crystal receptor; however, if the same chiral agent is added to different liquid crystal receptors, its spinning ability varies. With an increase in the concentration of the chiral dopant, the spinning capability in the system increases, leading to a decrease in CLC pitch and a blue shift in the initial color.…”