本篇論文主要研究三個主題，第一個是研究鐵電液晶摻雜膽固醇液晶平板樣品之反射顏色於整個白光區域做溫度調控。第二個是利用ITO膜本身可電致發熱特性，使鐵電液晶摻雜膽固醇液晶平板樣品之反射顏色於整個白光區域做低直流電壓調控。第三個乃透過可撓式石墨烯電致發熱薄膜與液晶同軸電紡絲結合，在施加低直流電壓下，使鐵電液晶摻雜膽固醇液晶微米纖維絲之反射顏色可電控涵蓋整個白光區域。 實驗結果發現，鐵電液晶摻雜入膽固醇液晶時，可提高其層列相與膽固醇相之相變溫度至室溫附近，當溫度接近此相變點時螺旋結構會大量解旋使反射波長大幅紅移但波帶結構仍維持完整。若進一步藉由簡單地施加低直流電壓於樣品ITO基板上，便可達到低電壓調控樣品反射波段於全白光區做寬頻域之反射波帶或顏色調控 (< 5 V)。另外，利用同軸電紡絲技術將鐵電液晶摻雜膽固醇液晶微米纖維絲噴塗於可撓式石墨烯電致發熱片，經過施加中等大小的直流電壓範圍(< 24 V)於石墨烯電致發熱片上，其反射顏色亦可於整個白光區做廣頻域之電調控。對於無論平板樣品或纖維樣品，其溫控或電控反射顏色特性皆具有可逆性與可重複性。由上述結果可知，可低直流電壓調控膽固醇液晶平板或微纖維樣品分別在智能顯示與雷射以及智能感測元件及可穿戴式智能布料上之應用有相當之應用潛力。

This thesis mainly focused on three topics. The first is the investigation for the temperature-tuning of the reflective color of the ferroelectric liquid crystal doped cholesteric liquid crystal (FLC-CLC) across the entire visible region. The second topic is the study for electrical tuning of the reflective color of the FLC-CLC across the entire visible region in a low DC voltage range by using the high electrothermal feature of the ITO film. The third one is the investigation for electrical tuning of the reflective color of the FLC-CLC across the entire visible region by merging a flexible graphene electrothermal heater with the coaxial electrospinng technique.
Experimental results show that the smectic-cholesteric phase transition temperature can be increased to near the room temperature such that the helix untwists significantly at near the transition temperature and thus the reflection band significantly red-shifts with a complete band structure. The reflection band or color of the FLC-CLC sample can be tuned across the wide band of the entire visible region when the ITO substrate of the sample is simply applied at a low DC voltage regime (< 5 V). In addition, the FLC-CLC microfibers are electrospun and sprayed on the flexible graphene electrothermal heater film. The reflection band or color of the microfibers can also be tuned electrically across the wide band of the entire visible region at a moderate DC voltage regime (< 24 V) on the graphene film. The planar or microfibers sample both possess a high reversibility and repeatability for the above-mentioned thermal and electrical tunabilities of the reflective band or color. Based on the above-mentioned experimental results, the electrically tunable FLC-CLC planar sample with ITO substrates and microfibers sample are highly potential for the applications of smart displays and lasers and smart sensors and textiles, respectively.

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