雷射光鉗是一項利用光壓特性的研究技術，在這一篇文章中，我們利用一臺852nm的半導體雷射為我們的光源，此光源是橢圓形光。經過歪向錂鏡將光源變成圓形光再經過一組空間濾波器，使用空間濾波器的目的是為了將圓形光的高頻雜訊過濾掉，將過濾完成的圓形光利用AO分光器的功能，取出做實驗的First Order 的光，目的是為了利用分光器在
開或關的時間非常短，用分光器來控制雷射光源的開或關可以免除雷射在開或關時的時間延滯，而減少實驗的誤差，我們將獲得的光經過一個架設在具有微調基座的凸透鏡，然後打進顯微鏡，使用凸透鏡的目的是為了調整雷射光源進物鏡的收斂角度或是發散角度，最後在顯微鏡中我們裝置一個極化光束分光錂鏡將捕捉的情形反射入影像系統CCD，由螢幕與電腦紀錄實驗過程。
我們研究了10μm 3μm 0.75μm三種微粒子，並分析了10μm粒子的水平捕捉力與 3μm粒子的垂直捕捉力與水平捕捉力，我們獲得10μm粒子的水平捕捉力約在10-11 Nt ~ 10-13Nt 之間，3μm粒子的垂直捕捉力約在10-14 Nt ~ 10-16Nt 之間，水平捕捉力約在10-12 Nt 附近。
同時我們利用Labview程式，模擬幾何光學的理論計算與環境條件，繪出幾何光學模型的曲線分布圖，用來與實驗比較。

Optical tweezers is a new technique for research in biological and physical sciences by using the radiation pressure. In this thesis, a diode laser, =853 nm, maximum power=50 mW, was used as the light source and a microscope was used for trapping and imaging. The laser beam pass through an anamorphic prime pair and a special filter to reduce the higher order modes and provide an ideal Gaussian laser Profile. An acoustic-optical modulator (AOM) was inserted into the beam for switching and modulating the tweezers. Before reflecting laser beam into the microscope, a beam expander and a convex lens expand and change the divergent angle of the laser beam for maximum power delivery and matching the imaging plane of the microscope. The trapped object was illuminated by the condenser and formed an image on a charge-coupled device (CCD) through a polarizing-cube beam splitter. A laser line filter put in front of the CCD to avoid the exposure saturation by the laser light. The images from CCD were monitored on the screen and tapped with a recorder.

We trapped three different sizes of micro spheres, 0.75, 3 and 10 m. The horizontal and vertical trapping forces were measured with 3, 10 m and 3 m micro spheres, respectively. The minimum vertical force can be measured was about 10-13 N and the horizontal force constant was about 10-6 N/m. These results were compared with the ray-optical model and a simple over damped motion of the particle. They are in good agreement

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