光镊利用强会聚激光对微粒产生的梯度力来捕获微粒, 可以进行无损、远程操控, 同时具有皮牛精度的测力特性, 已经成为物理学、生命科学和胶体化学等研究领域中不可缺少的研究工具。光镊效应可以表现微小的光子动量和角动量, 是物理学的重要教学工具。本文根据高斯光束传播和变换规律, 设计具有稳定捕获性能的最小化光镊, 并给出了典型参数。光镊系统由捕获激光、光束耦合系统、倒置生物显微镜和大数值孔径物镜组成, 成像系统由物镜、摄影目镜和CCD相机组成。本光镊系统具有紧凑特性, 同时通过保持物镜后瞳充满度来实现稳定捕获。在该最小光镊系统上, 可以根据用户需求增加光镊阱位操控系统、刚度调节系统和其他辅助设备以满足不同操控要求, 可以很好地满足科研和教学需求。

Optical tweezers, or single beam gradient force optical traps, can pull up and trap a dielectric microsphere at the focus. Optical tweezers have unique advantages, including non-contact force for cell manipulation and force resolution as accurate as pN. Optical tweezers have been widely applied in physical, biophysical and chemical studies. We describe how to build high performance of a minimum optical tweezers based on Gaussian beam propagation laws. The design of optical tweezers consists of laying out a trapping laser, several coupling lenses, an inverted microscope with a high numerical aperture objective, and a CCD camera. It is easy to add the trap position control system and stiffness control system to satisfy the different objects for scientific research and education.