Novel design and sensitivity analysis of displacement measurement system utilizing knife edge diffraction for nanopositioning stages.
Novel design and sensitivity analysis of displacement measurement system utilizing knife edge diffraction for nanopositioning stages.
复制标题
利用刀口衍射纳米定位台的位移测量系统的新颖设计和灵敏度分析。
DOI：
10.1063/1.4895912
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
Joshua A. Tarbutton
中科院分区：
文献类型：
--
作者：
Chabum Lee;Sun;Joshua A. Tarbutton
本文提出了一种新的设计和灵敏度分析的刀口为基础的光学位移传感器，可以嵌入纳米定位工作台。该测量系统由一个激光器、两个刀口位置、两个光电探测器和辅助光学元件组成，配置简单。刀刃平行于其移动方向安装在工作台上，两束分离的激光束入射在刀刃上。当载物台运动时，每个刀刃处的直接横向光和衍射光叠加，在检测器处产生干涉。用差分放大配置中的两个光电探测器测量干涉。提出的传感器的性能进行了数学建模，和光学和机械参数，波长，光束直径，从激光器到刀口到光电探测器的距离，和刀口形貌，对传感器输出的影响进行了研究，以获得一种新的分析方法来预测线性度和灵敏度。从模型中，所有参数，除了光束直径有显着的影响，测量范围和灵敏度的传感系统。为了验证该模型，两种类型的刀刃具有不同的边缘形貌用于实验。通过利用更短的波长、更小的传感器距离和更高的边缘质量，可以获得增加的测量灵敏度。实验结果表明，该模型与理论估算结果吻合较好。该传感器有望以低成本轻松实现到纳米定位平台应用中，并且这里介绍的数学模型可以用于刀口传感器的设计和性能估计。
This paper presents a novel design and sensitivity analysis of a knife edge-based optical displacement sensor that can be embedded with nanopositioning stages. The measurement system consists of a laser, two knife edge locations, two photodetectors, and axillary optics components in a simple configuration. The knife edge is installed on the stage parallel to its moving direction and two separated laser beams are incident on knife edges. While the stage is in motion, the direct transverse and diffracted light at each knife edge is superposed producing interference at the detector. The interference is measured with two photodetectors in a differential amplification configuration. The performance of the proposed sensor was mathematically modeled, and the effect of the optical and mechanical parameters, wavelength, beam diameter, distances from laser to knife edge to photodetector, and knife edge topography, on sensor outputs was investigated to obtain a novel analytical method to predict linearity and sensitivity. From the model, all parameters except for the beam diameter have a significant influence on measurement range and sensitivity of the proposed sensing system. To validate the model, two types of knife edges with different edge topography were used for the experiment. By utilizing a shorter wavelength, smaller sensor distance and higher edge quality increased measurement sensitivity can be obtained. The model was experimentally validated and the results showed a good agreement with the theoretically estimated results. This sensor is expected to be easily implemented into nanopositioning stage applications at a low cost and mathematical model introduced here can be used for design and performance estimation of the knife edge-based sensor as a tool.