一种基于色散补偿偏振低相干干涉测量法的微观绝对距离测量方法。

A Micro Absolute Distance Measurement Method Based on Dispersion Compensated Polarized Low-Coherence Interferometry.

作者信息

Sun Xun, Feng Kunpeng, Cui Jiwen, Dang Hong, Niu Yizhao, Zhang Xuping

机构信息

Institute of Optical Communication Engineering, College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, China.

Key Laboratory of Intelligent Optical Sensing and Manipulation (Nanjing University), Ministry of Education, Nanjing University, Nanjing 210093, China.

出版信息

Sensors (Basel). 2020 Feb 20;20(4):1168. doi: 10.3390/s20041168.

DOI:10.3390/s20041168

PMID:32093333

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC7070492/

Abstract

Micro absolute distance measurement (MADM) is widely used in industrial and military fields. To achieve high accuracy and frequency response, a polarized low-coherence interferometry (PLCI)-based method for MADM is proposed. The nearly linear relationship between the envelope center and m-order PLCI fringe (PLCIF) peak center is found and verified. Dispersion compensation is achieved by fringe peak position estimation and polynomial fitting to get rid of the dependence on an a priori model and birefringence parameters, and make this method very robust. Meanwhile, the zero-order PLCIF center is estimated and located to demodulate the measured displacement. Then, the measurement accuracy is raised by polynomial fittings. In comparison to conventional methods, the proposed method can effectively avoid jump errors and has a higher accuracy. Experimental results indicate that the measurement accuracy is higher than 19.51 nm, the resolution is better than 2 nm, and its processing data rate can reach 35 kHz.

摘要

微绝对距离测量（MADM）在工业和军事领域有着广泛应用。为实现高精度和高频率响应，提出了一种基于偏振低相干干涉测量法（PLCI）的MADM方法。发现并验证了包络中心与m阶PLCI条纹（PLCIF）峰值中心之间的近似线性关系。通过条纹峰值位置估计和多项式拟合实现色散补偿，摆脱了对先验模型和双折射参数的依赖，使该方法具有很强的鲁棒性。同时，估计并定位零阶PLCIF中心以解调测量位移。然后，通过多项式拟合提高测量精度。与传统方法相比，该方法能有效避免跳变误差且具有更高的精度。实验结果表明，测量精度高于19.51 nm，分辨率优于2 nm，其处理数据速率可达35 kHz。