Electro-Optic Potential of Room and High Temperature Polymer Stabilised Blue Phase Liquid Crystal

Abstract

In the field of liquid crystals, blue phases (BPs) are one of the most unique and interesting sub-phases. Blue-phase liquid crystal holds the potential to become next-generation display and photonics device because of its sub-millisecond gray-to-gray response time, alignment-layer-free process, optically isotropic dark state, and cell gap insensitivity. The BPLC is a highly chiral liquid crystal system possessing crystal like unit cell structure and exist over a small temperature range (0.5-2 °C) between isotropic and chiral nematic (N*) thermotropic phase. The narrow phase range has been an intrinsic problem for blue phase, and a useful strategy of widening the phase is by adding polymer to form a polymer stabilised blue phase liquid crystal. In this paper, we demonstrate polymer stabilization using two different cases: a room temperature mixture containing E8, PE-5CNF and CPP-3FF, and a high temperature mixture using a single molecule blue phase liquid crystal material, TCB5. Comparison of the polymer stabilization effects on these two cases will be discussed, in the perspective of their potential in electro-optic applications.