本論文研究主題為提出兩種可調式連續線性偏振旋轉器，全文共分為三部分，第一部分針對楔形液晶盒及膽固醇液晶進行研究，利用光斑大小驗證楔形液晶盒厚度的準確性，再利用膽固醇液晶反射頻譜及卡諾楔形盒理論探討手性分子(CB15)對向列型液晶(HEF951800-100)之螺旋扭轉力(HTP)值，最後討論膽固醇液晶特定螺距下在(1)相同液晶分子總旋轉角及不同螺距下及(2)不同液晶分子總旋轉角及相同螺距下對出射光偏振度之影響。第二及第三部分將分別提出利用楔形液晶盒製作可調式連續偏振旋轉器及利用圓形配向製作可調式連續偏振旋轉器。第二部分將透過楔形液晶盒讓液晶在空間上形成非完整週期結構，再將楔形液晶盒吸附環型磁鐵以使其受磁場作用改變液晶盒厚度，進而在厚度變化下改變偏振旋轉。第三部分為利用圓形配向及水平配向使圓形配向面形成圓對稱結構之排列，再將此液晶盒吸附磁鐵以使其受磁場作用改變液晶盒厚度，在厚度變化下改變每個結構之螺距長度及螺距數量進而改變出射光的偏振旋轉。;The research topic, divided into three sections, of this thesis is to propose two kinds of tunable continuous linear polarization rotators. In the first section, we study the wedge-shaped liquid crystal (LC) cell filled with cholesteric LCs (CLCs). The thicknesses of the wedge-shaped LC cell, measured by different light spot sizes, are examined, and the helical twisting power value of CB15 with respect to HEF951800-100 is discussed by using the transmittance spectrum of the CLCs and the Cano wedge cell theorem. Finally, the influences of degree of linear polarization values of the output light through the CLCs with (1) the same total twisted angle but different pitches, and (2) the same pitch length but different total twisted angles are discussed. The second and third parts of this thesis propose a tunable continuous polarization rotator using a wedge-shaped LC cell and the alignment layer treated by circular rubbing treatment, respectively. The second part will make the CLC form a non-integer periodic structure in space by the wedge-shaped LC cell, and then examine the polarization rotation angle after the cell gap is tuned by magnetic force (magnets). The third part is to use circular alignment and horizontal alignment layers to form a specific LC alignment. The polarization rotation angles of the output light can be changed by the variations of pitch length and pitch numbers according to the variations of the thickness of the LC cell by ring magnets.
