二維奈米黏土之添加對液晶顯示器離子效應的影響

Influence of doping 2D nanoscale clay on the ion effect in a LCD

林奕升(I-Sheng Lin)

指導教授 ： 李偉

中原大學/理學院/物理研究所/碩士(2010年)

https://doi.org/10.6840/cycu201000060

摘要

本論文旨在探討二維奈米黏土之添加對於液晶顯示器離子效應的影響。研究發現，不論奈米黏土為天然黏土礦或人工合成材料，若經先行研磨再混入液晶，並於室溫下將液晶混合液注入液晶盒，則奈米黏土之添加可明顯抑制液晶盒的離子效應。
由實驗結果所得之重要結論包含：一、經由交流電壓驅動之光學量測可知，不論奈米黏土為天然的抑或人工合成材料，其添加對於液晶盒之光穿透強度、反應時間等實驗結果不會有太大的變化；二、在水平180配向、外加一交流電壓之條件下，瞬間關閉電壓並不會引發可觀察到的迴流行為；以DIMOS模擬的結果也顯示無明顯迴流現象；三、於外加直流偏壓條件下，摻入液晶的微量奈米黏土會使得穿透度與電容曲線的遲滯寬度變小，此為奈米摻雜物抑制離子屏蔽效應的重要證據；四、在暫態電流的定性量測條件下，摻有微量奈米黏土的樣品其電流訊號減弱，此為奈米黏土抑制離子濃度的重要證據；五、電壓保持率量測結果顯示，摻有微量奈米黏土的樣品其電壓保持率較高。

關鍵字

液晶顯示器 ； 奈米黏土

並列摘要

The purpose of this thesis is to explore the influence of doping two-dimensional nanoscale clay on the ion effect in a liquid-crystal display. According to our research, no matter the nanoscale clay is natural or synthetic, the addition of the clay as a dopant can obviously suppress the ion effect in the liquid-crystal cell as long as the dopant material is milled in advance and then injected into the cell at room temperature.
Several major findings from the experimental results are as the following: 1. The addition of clay has no apparent impact on AC electro-optical properties such as transmittance or response times. 2. Under the conditions of antirubbing alignment and AC driving, no observable behavior of backflow can be induced by switching off the applied voltage, which is confirmed by simulations using DIMOS. 3. Under DC driving voltage, the transmittance and capacitance hystereses are both suppressed by the slight clay dopant, providing important evidence for the suppression of the screening effect. 4. The magnitude of transient current becomes weaker in the cell with slightly doped clay, which is a proof for the suppressed ion effect by the dopant. 5. In view of the voltage-holding-ratio data, it is clear that the cell consisting of a minute amount of clay can increase the voltage holding ratio effectively.

並列關鍵字

nanoscale clay ； liquid crystal

參考文獻

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[28] 王彥超，《添加碳奈米管之配向劑於液晶顯示器之應用》，碩士論文，中原大學應用物理研究所，民96年6月。

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