Self-supported liquid crystal film for flexible display and photonic applications

A liquid crystal film consisted of nano-sized liquid crystal (LC) droplets <350 nm which is formed via polymerization induced phase-separation from LC/monomer composite exhibits an optically isotropic phase with mechanically self-supporting behavior. However, the film shows a slight light scattering, which deteriorates either a dark state or transparency when applied to either flexible LC displays or tunable photonic devices. Herein, we demonstrate an optically isotropic phase containing LC droplets smaller than 100 nm which exhibits a high transparency and supports bending up to 4 mm of the radius of curvature. Such nano-sized LC droplets induce strong anchoring of LC molecules at polymer interfac so that the decay response time of the device reduces to a microsecond. The paper reports the electro-optics of LC displays and diffractive properties of tunable diffractors associated with the LC droplets in detail. The bendable device demonstrated here can overcome the drawback of the conventional LC devices with non-flexibility and will have potential applications in free-form and flexible display format.