在過去幾年研究中，液晶最迷人的特質在於異向性，即是垂直液晶導軸方向與平行液晶導軸方向的物理特性(介電係數、折射係數……等)不同，由於這天生結構上差異，使得液晶在顯示器領域中，吸引學者們以及顯示器產業的注意力，但是擁有天生異向性特質，對摻雜奈米粒子或者是膠體粒子來說，卻是很難均勻分散在液晶中，因為液晶連續彈性體理論和拓樸缺陷，使得奈米粒子無法均勻混入到液晶，並且隨著時間演化，奈米顆粒會彼此聚集，然而，中孔洞氧化矽空心球卻是有機會解決顆粒聚集的人工材料，除此之外，可調式散射效應更能廣泛應用在其他領域中。
這篇論文的主旨是研究氧化矽空心球散射機制和使得散射型元件的光電特性更為完美，中孔洞氧化矽空心球在肉眼以及光學顯微鏡尺度下，可以形成均勻混濁的暗態，相反地，在沒有中空結構以及表面無孔洞情況下，氧化矽實心球在肉眼以及光學顯微鏡尺度觀察，不能呈現均勻混濁的暗態。此外，隨著外加電場增加，散射區塊將會逐漸消失，就像是聚合物分散液晶(PDLC)，根據觀察中孔洞氧化矽空心球特殊光學現象，我們提出在中孔洞氧化矽空心球散射模型，並且與聚合物分散液晶(PDLCs)和膽固醇型液晶(CLCs)互相做比較，由於中孔洞氧化矽空心球特殊的光電特性，為了改善電子窗簾工作效能，利用同時加入高分子聚合物以及手性分子來提升光電特性，除了量測穿透度之外，還量測中孔洞氧化矽空心球反應時間以及磁滯效應。
為了想更了解中孔洞氧化矽空心球散射機制和周圍液晶排列方式，透過摻雜偶氮染料的方式，這是因為偶氮染料在光激發情況下，會瞬間轉動液晶排列，根據光異構化的偶氮染料，產生動態穿透率變化，可以推斷液晶分子動態響應行為還有驗證中孔洞氧化矽空心球散射模型，除此之外與聚合物分散液晶(PDLCs)和膽固醇型液晶(CLCs)互相做比較，此外，還有改變激發能量觀察中孔洞氧化矽空心球動態響應時間。

Over the past several years of research liquid crystals (LCs), the most fascinating field is that the anisotropic characteristic, indicating the perpendicular direction of dielectric constant or refractive index is different from the direction of parallel. Due to the intrinsic anisotropic characteristic, the application of liquid crystal in the display field is attracting researchers and the display industry. However, the behavior of innate anisotropic fluid, such as nanoparticles or colloidal particles is hard to well disperse in LCs. As the restored elastic continuum of LCs and generated topological defects, the doped nanoparticles couldn’t uniformly disperse in LCs and will gradually aggregate with the time or applied voltage. However, Mesoporous silica hollow sphere (MPSHS) is a candidate artificial material to solve particles aggregation in LCs and also make the controllable scattering effect for further application.
The subject of this thesis is to study the scattering phenomenon of MPSHSs and make a better performance of scattering devices, such as smart window. MPSHS-LCs exhibit uniform opaque in the naked eye and optical microscope images. Contrary, in the silica solid spheres (SSS) which without mesoporous on the surface of SSS and hollow structure, the opaque is not uniformly distributed in the naked eye and optical microscope images. In addition, with the increasing applied electric field, the dark section would be disappeared likely to the polymer dispersed liquid crystal. Noticing the particular phenomenon, we proposed the mechanism of light scattering and compare to the scattering phenomena of the polymer dispersed liquid crystals (PDLCs) and cholesteric liquid crystals (CLCs). According to the specific electro-optical behavior of MPSHSs, we improve the performance of the smart window and we also propose the mixture of polymer (NOA61) and chiral (S811) to enhance the electro-optical property of MPSHSs. Besides measuring the transmittance, we also measure the response time and hysteresis effect which involve the anchoring of MPSHSs
In order to find out more detailed about the light scattering mechanism and the orientation of liquid crystal surrounding to the MPSHSs so we use the azo dye (Methyl Red) which could induce the transient reorientation of liquid crystal by photoisomerization. Based on the dynamics transmittance after the photoisomerzation of azo dye (Methyl Red), we could infer the reorientation of liquid crystal and the light scattering structure. In addition, we compare this phenomenon with PDLCs and CLCs. Moreover, the intensity of excitation laser energy is changed to observe the corresponding response about MPSHSs.

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