高分子穩定型藍相液晶光電特性之模擬研究

Simulation of the Electro-Optics of Polymer-Stabilized Blue Phase Liquid Crystal

胡水上(Shui-Shang Hu 胡水上)

指導教授 ： 吳俊傑 ； 陳殿榮

國立臺北科技大學/電資學院/光電工程系研究所/博士(2013年)

https://doi.org/10.6841/NTUT.2013.00561

摘要

在本論文中，我們提出一個「液晶指向矢模型」來模擬和解釋藉由垂直電場或水平電場驅動的高分子穩定型藍相液晶(PS-BPLC)盒之光電特性，並探討克爾效應的本質。我們藉由堆疊一定數量的向列型液晶(NLC)來模擬PS-BPLC盒，為了要模擬和解析實驗結果，我們調整液晶盒的厚度(dbp)和電壓的倍數(M)來貼合實驗結果。另外，在任何範圍的電場作用下，藍相液晶所誘導之雙折射和液晶分子和電場方向夾角的平均餘弦值之間具有線性關係，此結果顯示BPLC的電場誘發雙折射本質上即為指向矢的指向變化所呈現的整體特性。
利用液晶指向矢模型，我們不僅可以有效地描述BPLC盒的光電特性，還能夠計算BPLC盒的反應時間，其模擬結果與實驗結果亦相當符合。這樣的理論模型和模擬結果將有助於對BPLC工作機制方面的了解，並對於未來在設計BPLC相關產品的應用上有極大的幫助。

關鍵字

液晶指向矢模型 ； 藍相液晶 ； 克爾效應

並列摘要

In this dissertation, we propose a “director model of liquid crystal” to model and interpret the photoelectric characteristics of the polymer-stabilized BPLCD driven by a vertical electric and horizontal electric field. Simultaneously, the essentials of the Kerr effect are investigated. We consider the PS-BPLC cell as a stacking of a number of NLC layers which can be simulated by the director model. To simulate the experimental results, we adjusted the value of dbp and the voltage multiplier M to fit the experimental results. In addition, the induced birefringence in the BPLC is linearly proportional to the average cosine of the angle with respect to the direction of the electric field. This result shows that the electric-field-induced birefringence of BPLC is essentially the overall characteristic caused by the direction change of the directors in the external electric field.
Using the liquid crystal director model, we simulated the electro-optical properties and calculated the response time of the IPS-BPLC cell, and the simulated results match the experimental results well. Such a theoretical model and the simulation results will contribute to the understanding of the physical mechanism of BPLC and be of great help for the future design of BPLC products.

並列關鍵字

director model ； blue phase liquid crystal ； Kerr effect

參考文獻

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