How to calibrate an object-adapted optical trap for force sensing and interferometric shape tracking of asymmetric structures
How to calibrate an object-adapted optical trap for force sensing and interferometric shape tracking of asymmetric structures
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DOI：
10.1364/oe.22.025242
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发表时间：
2014-10-20
期刊：
影响因子：
3.8
通讯作者：
Rohrbach, Alexander
中科院分区：
文献类型：
--
作者：
Koch, Matthias;Rohrbach, Alexander
光陷阱已被证明是一种灵活且强大的微尺度 3D 操作工具。然而，当涉及到粒子位移和力的敏感测量时，需要彻底的校准程序，这对于捕获的球体来说已经是很高的要求了。对于形状更复杂的不对称结构，例如螺旋细菌，需要建立新的校准方案。该论文描述了如何提取微小螺旋细菌的各种校准参数的不同方法，该细菌被扫描线光镊捕获并进行形状跟踪。通过后焦平面干涉测量法测量细菌每个斜面散射光的微小相位差，提供有关细菌快速变形的精确且高带宽的信息。提出了一种估计链状结构上的光学力的简化理论模型。研究不对称粒子的光学捕获和跟踪的人们应该会对这里介绍的方法感兴趣。 (C) 2014年美国光学学会
Optical traps have shown to be a flexible and powerful tool for 3D manipulations on the microscale. However, when it comes to sensitive measurements of particle displacements and forces thorough calibration procedures are required, which can be already demanding for trapped spheres. For asymmetric structures, with more complicated shapes, such as helical bacteria, novel calibration schemes need to be established. The paper describes different methods of how to extract various calibration parameters of a tiny helical bacterium, which is trapped and tracked in shape by scanning line optical tweezers. Tiny phase differences of the light scattered at each slope of the bacterium are measured by back focal plane interferometry, providing precise and high bandwidth information about fast deformations of the bacterium. A simplified theoretical model to estimate the optical forces on a chain like structure is presented. The methods presented here should be of interest to people that investigate optical trapping and tracking of asymmetric particles. (C) 2014 Optical Society of America