Studies of Hysteresis and Residual Birefringence in Polymer Stabilized Blue Phases LC Display

• Main Authors: Chun-Yuan Fan, 范鈞源
• Other Authors: Tsung-Hsien Lin
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/61462945669789026546

碩士 === 國立中山大學 === 光電工程學系研究所 === 99 === Blue-Phase liquid crystal display possesses potential to become next generation display technology because of its submillisecond response time, alignment-layer-free process and wide view angle. Intrinsically, BP only operates across a narrow temperature range due to the influence of intrinsic structural defects. Recently, the temperature range of BP has been successfully extended beyond 60K through the polymer-stabilized effect. Unfortunately, the structure of the polymer networks poses a number of problems, for instance, hysteresis effect, which degrades the accuracy of grayscale control, and residual birefringence, which decreases the contrast ratio of LCDs. This paper investigates the voltage-induced hysteresis and residual birefringence in the polymer-stabilized blue phase I and II, under various phase separation conditions and material ratio. Based on experiment result, the polymer network morphology, distribution and pure BP temperature can result in a variety of PSBP electro-optical properties. Hysteresis and residual transmittance free PSBP display could be achieved by choosing appropriated phase separation condition and material ratio. Key word：blue phase、monomer、hysteresis、residual transmittance