摻雜絕緣奈米粒子之扭旋向列型液晶元件之光電特性研究

Abstract

此篇論文的主要目的在於觀察並且比較摻雜絕緣奈米粒子的九十度扭旋向列型液晶晶胞之光電特性。在實驗過程中，我們測量了光穿透率對電壓曲線和暫態電流對時間曲線圖。實驗結果顯示，微量地摻雜絕緣奈米粒子像是四氮化三矽、氧化鋅或二氧化鈦能有效地降低液晶中移動離子的濃度以致於降低了暫態電流和臨界電壓。同時在有摻雜的液晶晶胞中亦能維持高於95%的電壓保持率。絕緣奈米粒子相較於以往摻雜奈米碳管的低電壓保持率是一個較好的摻雜材料。 實驗結果顯示吸附離子的能力幾乎和粒子的種類無關。我們推測離子濃度的降低是由於離子被極化的絕緣奈米粒子所捕捉。

The main purpose of this thesis is to investigate the electro-optical properties of insulated nanoparticle-doped 90。 twisted nematic liquid crystal cells. We measure their transmittance curve and transient current. The experimental results show that a minute addition of insulating nanoparticles such as , , and lead to a reduction of the ion concentration in the cells so as to reduce the transient current and the threshold voltage. Simultaneously, the voltage holding ratio can be held higher than 95% which is a superior feature compared to the carbon nanotube doped cells. These experimental results are almost independent of the type of the nanoparticle. We speculate that the reduction of the ion concentration is due to the ion trapping by the polarized dielectric nanoparticles under an external electric field.