光鉗系統之建置校正及基礎應用之研究

Abstract

本論文分為兩個部份。第一部份在介紹光學嵌住理論以及光鉗系統的發展及應用。本實驗室去年剛引進光鉗系統，準備做生物細胞相關的研究。因此除了詳細介紹光鉗系統的工作原理外，更著重在本實驗室光鉗的架設方法、過程，以及校正的工作，目前已經建立起一套可以被實用在生物細胞研究的光鉗系統了。接下來更對於本光鉗系統的嵌住力，剛性係數等做一系列的實驗，詳加探討光學嵌住現象，以便日後應用在生物細胞力學分析。第二部份是微量液體黏滯係數的測定。利用顯微鏡觀察直徑1μm大小的微粒，在液體中的布朗運動，且藉由理論可以得知布朗運動均方位移和黏滯係數的關係。因此我們使用攝影機拍攝下布朗運動的情形，做多組實驗，並且由統計的結果去反算出水的黏滯係數，得到的實驗值是令人滿意的。因此我們再使用同樣的方法，去測定未知溶液的黏滯係數。這種新的測定方法只需要微量液體即可，盼望在未來可以使用此方法，應用在微小世界的環境測定。

Last year, we set out to study the mechanism of living cells, and we purchased the optical instruments to set up an optical tweezer system. This thesis contains two parts. In the first part we introduce the theory of the optical trapping, the working theory of optical tweezers, the constructing and alignment procedure. Now we have constructed a system that can be applied to study the living cells. We also experimented with the 5μm microspheres to investigate the trapping force and the stiffness of our optical tweezers, preparing for the future work of biologically research. In the second part we focus on the Brownian motion and the measurement of viscosity. We used the microscope to observe the Brownian motion of 1μm microspheres and recorded them by CCD camera. Using the theoretical formula we can obtain the relation between the mean squared displacement of the particles and the medium’s viscosity. By experimenting repeatedly we got a lot of data and use the statistical method to compute the viscosity of water. The experimental value is precise and satisfactory. Therefore we used the same method to examine the unknown liquids. We only needed a small quantity of liquid to measure the liquid’s viscosity, and the method is different from any other traditional method. In the future, we can apply the technique to explore the microcosmos.