在本論文中，我們探討微米球摻雜在高分子分散膽固醇液晶(Polymer Dispersed Cholesteric Liquid Crystal)和液晶中的光電特性。它們可以藉由電場去控制折射率匹配，使元件從散射態轉到穿透態。 實驗第一部份我們將微米球加入液晶討論對比度，第二部份將微米球加入高分子分散液晶中，在無電壓時增加不透明狀態的效果，因此提高了對比度。 最後我們製作摻雜20%直徑3μm PMMA球PD-ChLC元件，操作電壓為38伏特，其對比度為3.3:1。我們也發現加入微米球不只能降低操作電壓，並且也讓我們減少了單體和液晶使用量，因此這項技術也可以降低元件製作的成本。 In this study, we investigate the electro-optic properties of liquid crystal device which is fabricated by doping microspheres in liquid crystal and polymer dispersed cholesteric liquid crystal. It could be switched from light scattering state to transparent state by applying the electric field to control the refractive index matching between materials. In the first part of the experiment, we discuss microsphere doped liquid crystal device contrast ratio. In the second part of the experiment, we doped microspheres in PD-ChLC to decrease the transmission of the opaque state when the voltage is turned off result in increasing the contrast. Finally, we make a PD-ChLC device that is doped by 20% PMMA microspheres of 3μm in diameter. The operating voltage and the contrast are 38 V and 3.3:1, respectively. We find that the doping of microsphere in PDLC can not only decrease the operating voltage, but also reduce the amount of usage of monomer and liquid crystal. Thus, this technique can reduce the production cost.