新型二色性黑色染料應用於無偏振片液晶元件

Abstract

二色性黑色染料摻雜於液晶元件中可提高元件之對比度，本研究配製新型二色性黑色染料PC B1並應用於無偏振片液晶元件系統。此研究配製的黑色染料PC B1之吸收光譜均勻且涵蓋可見光範圍，解決市售黑色染料S428（from Mitsubishi，Japan）吸收光譜不均勻導致藍光波段漏光的問題。 實驗中從五種不同吸收波段之二色性染料Y1、AO1、AZO1、AR1，AB4依不同比例調配黑色染料PC B1（Y1：AZO1：AR1：AB4＝1.0：0.85：1.8：2.5）及PC B2（Y1：AZO1：AO1：AB4＝1.0：0.7：4.7：3.9）， 其中PC B1之吸收光譜均勻且涵蓋可見光範圍，因此摻雜此黑色染料於TN型液晶元件中量測光電特性並應用於無偏振片液晶元件。此研究使用高分子穩定型膽固醇液晶模式（polymer-stabilized cholesteric texture，PSCT）作為無偏振片液晶元件，將新型黑色染料PC B1添加於高分子聚合物穩定型膽固醇液晶系統其對比度在無偏光片下可由6：1提高至19:1，並具有連續灰階及5.44 毫秒的快速響應。

Black dichroic dyes doped in LC materials increase the contrast ratio of LC devices. In this reseach, black dichroic dyes were prepared and applied to polarizer-free LC devices. The absorption spectrum of the black dichroic dyes PC B1 covers the entire visible range, which solves the light leakage issue of the commercialized black dichroic dyes S428 (from Mitsubishi, Japan) due to weak absorption in blue. 5 kinds of dichroic dyes with different absorption spectra were mixed to prepare black dichroic dyes PC B1 (Y1 : AZO1 : AR1 : AB4 = 1.0 : 0.85 : 1.8 : 2.5) and PC B2 (Y1 : AZO1 : AO1 : AB4 = 1.0 : 0.7 : 4.7 : 3.9). Between these two black dichroic dyes, PC B1 having uniform absorption spectrum covering the entire visible range is doped in TN LC devices to study the electro-optical properties and then applied to polarizer-free LC devices. Polymer-stabilized cholesteric texture (PSCT) is applied as the polarizer-free LC device in this reseach. The PC B1 doped in PSCT device increases the contrast ratio from 6:1 to 19:1 comparing with pure PSCT devices and has continuous gray scales with 5.44 ms fast LC response.