垂直配向液晶盒的錨定特性

Abstract

我們完成了一個決定垂直配向液晶盒錨定能的方法。由電腦計算理論曲線與實驗測到的液晶盒光學相位差作比對，可以精確的量到垂直配向液晶盒的錨定能，預傾角，液晶盒厚度。我們量測了一系列不同表面處理的液晶樣品錨定能。摩擦配向的垂直配向液晶盒預傾角隨著摩擦深度的增加而下降，但是極角錨定能(polar anchoring energy)幾乎不隨摩擦強度改變 (3*10-4 J/m2)。光配向的垂直配向液晶盒預傾角及極角錨定能皆隨著曝光量的增加而下降。其中有極角錨定能強達3*10-3 J/m2的樣品，其均勻性，離子效應，動態響應，都已經接近摩擦配向的垂直配向液晶盒。我們也透過漏光量測，定性的得到樣品的扭轉錨定能(azimuthal anchoring energy )。在紅外線吸收光譜的量測中可以發現造成液晶分子排列是由於配向膜分子在空間中的非等向性。

We have developed a method to determine the anchoring energy of homeotropically aligned liquid crystal cells. The polar anchoring, pretilt angle, and cell gap of a homeotropically aligned liquid crystal cell could be determined precisely via fitting the experimental optical phase difference and the computer calculated curve. We measured different kinds of liquid crystal cells. In the cells prepared by rubbing, the pretilt angles decreased whit the rubbing strength increasing, but the anchoring energy didn’t change. In the photo aligned cells, the pretilt angles and anchoring energy decreased with the exposing time increasing. We got a photo aligned liquid crystal cell whose uniformity, ion effect, and dynamic response was similar to the rubbing one. We also got the azimuthal anchoring energy in qualitatively by measuring the leaked light of the cells. The anisotropy of alignment layer induced the orientation of liquid crystal molecular could be confirmed by the FTIR measurment.