本論文主要是在探討雷射光鉗的作用，對1μm大小的聚苯乙稀微粒及微粒團運動的影響，之前學長姐們已經對3μm聚苯乙烯微粒在雷射光鉗中的垂直捕捉力與水平捕捉力方面做了些研究，所以本文主要是在研究分析1μm大小的聚苯乙稀微粒及微粒團在雷射光鉗中所受的作用力，當微粒團被捕捉在雷射光鉗中，在平衡點之上或之下時，因微粒團之結構不對稱，會受到光鉗作用的扭力，而做順時針或逆時針之轉動，分析微粒團的轉動狀態，可以求得雷射光鉗施予的轉動力矩，對半徑約2μm的微粒團，其力矩約 。另外，利用雷射光鉗壓縮2或3個1μm大小的微粒，長一些的壓縮時間可以獲得大一點的微粒間的作用力，關閉雷射光鉗後微粒會因熱擾運動而分離，藉由探討分析單一微粒的熱擾運動的運動路徑與時間的關係，可求得微粒間的作用力約為 。我們也改變微粒的顏色，用紅色或藍色的微粒來做觀測，但並沒有影響微粒間的作用力。藉由微粒的熱擾運動及微粒團的轉動，我們可以初步分析了解雷射光鉗的捕捉力及扭力。

　　The article is mainly discuss the affection of laser tweezers, the influence on about 1μm size micro-polystyrene bead and cluster, previous the senior already have done research to the vertical and horizontal trapping force on 3μm micro-polystyrene bead in laser tweezers, therefore this article analyzes the force of 1μm size micro-polystyrene bead and cluster in laser tweezers, when the cluster is capture in the laser tweezers, the position up and under the focus，because the cluster is asymmetrical, receives the torsion from laser tweezers, it makes clockwise or anti-clockwise rotation, the analysis of the cluster rotation state, we can obtain the torque of laser tweezers apply on the cluster of radius approximately 2μm is . Moreover, compressing two or three 1μm size particle using laser tweezers, the particles obtain bigger interaction force while compressing longer time. Close the laser, these particles separate by thermal motion, the analysis of a single particle movement and time relations, we can obtain the interaction force is about . We also change the color of micro-polystyrene bead, using red or blue particles to observe, but the color does not affect the interaction forces between particles. Therethrough the thermal motion of a particle and the rotation of the cluster, we can roughly analyze and understand the trapping force and torsion of laser tweezers.

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