旋轉塗佈旋光性液晶薄膜與其光學性質探討

Abstract

現代人已經離不開對3C產品的依賴性，尤其對於感官上的需求，特別是在視覺上的呈現，故顯示器的畫質提升，為各科技業者必爭之地。 目前液晶顯示器為提升其光學特性以達使用者的便利性，如可視角的提升和減少環境光對顯示器的影響，常在偏光片上搭配四分之一波片，其又稱為相位補償膜，藉由線偏振光轉化為圓偏振光的特性，來達到前述之效果。 由於市售四分之一波片之配向角度，大都是經由成膜後，再進行角度45度的裁切，此過程會造成基材樣品的浪費，且基材寬幅受到較大限制。 本研究使用旋光性液晶做相位補償膜，利用旋轉塗佈法調控膜厚，研究其光學特性，並使旋光性使液晶自旋角度，以開發軸向45度塗佈型1/4相位補償模，來改善現市售產品的缺陷。而利用旋光性液晶做相位補償膜，由於其輕薄之特性，更適用在可撓式顯示器上。

In recent years, the development of large-area displays with higher resolutons has attracted great interest for researchers in research institutes and high-tech companies. For liquid crystal displays, the viewing angles are important for better consumer experiences. Usually phase retardation films, optical polarization films with quarter wavelength retardation films, are used. The effect is achieved by converting linear polarization lights to circular polarization lights. On the market, the commercially available quarter wavelength retardation films are produced by cutting the original films at angles of 45 degrees; during the manufacturing processes, more films are wasted and the sizes of the substrates are limited. In this work, we study the fabrication of phase retardation films using chiral liquid crystals. The film thicknesses are controlled by the spin-coating rates. Depending on the chiral properities of the liquid crystals, quarter wavelength retardation films are developed. This study provides better understanding in designing compensation films for flexible display applications.