This paper investigates the voltage hysteresis effect and residual birefringence in the polymer-stabilized blue phase I and II, under various phase separation conditions. By irradiating samples with ultraviolet (UV) light and curing the samples at a reduced temperature, the polymer in the blue phase formed a compact network along the direction of the UV light irradiation. The dense polymer network pinned the cubic lattice structure of the blue phase enabling it to return to its original optical isotropic state. In this manner, hysteresis and residual birefringence were suppressed from 4.16% to 1.67% and 0.057% to 0.002%, respectively. Although the driving voltage remained high, the reduction in hysteresis and residual birefringence are precisely the advancements required for the accelerating development of blue-phase liquid crystal displays.
© 2011 IEEE
Chun-Yuan Fan, Hung-Chang Jau, Tsung-Hsien Lin, Fang Cheng Yu, Tai-Hsiang Huang, Chuyu Liu, and Norio Sugiura, "Influence of Polymerization Temperature on Hysteresis and Residual Birefringence of Polymer Stabilized Blue Phase LCs," J. Display Technol. 7, 615-618 (2011)