光鉗是利用光操控微米等級微粒之技術，由於其非接觸與非破壞式的特點在生醫及材料科學方面皆多有應用，其輸入的光場與微粒交互作用之下能使微粒操控性能產生多樣的結果。本論文利用偶氮染料SD1經光配向後結合向列型液晶製作出可調製雷射光相位的特殊元件q-plate(QP)，並利用此元件產生不同階數之渦流光束，將之與光鉗技術結合，研究觀察兩種向列型液晶微球在光渦流光鉗下之轉動行為表現。
本論文的研究分成兩個部分。第一個部分將敘述QP的製作方式以及製作參數，並參考文獻，利用線偏振及圓偏振光輸入QP，觀察不同QP所產生的光斑形態以檢驗其q值，並得到與文獻相符的實驗結果；第二部分將QP元件與光鉗系統結合，在輸入光源為660 nm的圓偏振光鉗架設中加入了使用SD1光配向材料製作的QP，使得光鉗操作光源同時具有軌道角動量以及自旋角動量，並藉此操控雙極型及輻射發散型的向列型液晶微球。本論文比較在不同光鉗功率及不同階數的渦旋光(l = 6、8、10、12)光鉗作用下，不同結構(雙極型、輻射發散型)及大小的液晶微球轉動行為的表現。實驗結果顯示，其轉動行為表現與液晶微球具有雙折射性與否、渦旋光鉗單位光強軌道角動量大小以及微球大小皆有相關。

Optical tweezers are extensively applied in biomedical and materials sciences because it can provide a noncontact and nondestructive method for manipulating micron-sized particles. The interaction between the microspheres (MSs) and the incident light field of optical tweezers has attracted increasing attention. This thesis aims to investigate the orbital motion of NLC MSs under the manipulation of optical vortex tweezers (OVTs). We used the azo dye SD1 as the photo-alignment material to fabricate the q-plates (QPs), which were subsequently integrated into the optical tweezers to generate the optical vortex beam.
This thesis is divided into two parts. In the first part, we established the photo-alignment setup to fabricate the QPs and demonstrated their usefulness. In the second part, the QPs were integrated with a circularly polarized optical beam (wavelength: 660 nm) as vortex tweezer beams, with vortex beams of l = 6, 8, 10, and 12, to manipulate the NLC MSs. The QP-integrated optical tweezers possessed spin angular momentum and orbital angular momentum at the same time. The optical tweezers can rotate the NLC microdroplet through angular momentum transfer. The orbital motions of the NLC MSs manipulated by the optical tweezers were investigated under various experimental conditions, such as LC structure and diameters of the MS and the power and value of l (l = 6, 8, 10, 12) of the incident vortex beam. Experimental results showed that the orbital motion of the NLC MSs depends on the sizes of the MSs, the l value of the incident vortex beam, and the internal LC structure of the MSs.

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