动态啁啾脉冲干涉的快速绝对距离测量  

Rapid absolute distance measurement by dynamic chirped pulse interferometry

作　　者：徐昕阳 赵海涵 钱治文 刘超 翟京生 吴翰钟 Xu Xin-Yang;Zhao Hai-Han;Qian Zhi-Wen;Liu Chao;Zhai Jing-Sheng;Wu Han-Zhong(School of Marine Science and Technology,Tianjin University,Tianjin 300072,China;Hubei Key Laboratory of Gravitation and Quantum Physics,Key Laboratory of Fundamental Physical Quantities Measurements,Ministry of Education,PGMF and School of Physics,Huazhong University of Science and Technology,Wuhan 430074,China)

机构地区：[1]天津大学海洋科学与技术学院,天津300072 [2]华中科技大学物理学院,精密重力测量国家重大科技基础设施,基本物理量测量教育部重点实验室,引力与量子物理湖北省重点实验室,武汉430074

出　　处：《物理学报》2021年第22期11-18,共8页Acta Physica Sinica

基　　金：国家重点基础研究发展计划(批准号:2016YFC1401203);国家自然科学基金(批准号:61505140,62075162);天津市自然科学基金(批准号:18JCYBJC17100)资助的课题.

摘　　要：提出了一种基于动态光学频率梳啁啾脉冲干涉的绝对距离快速测量方法.借助于重复频率的线性扫描,可获取啁啾光谱干涉信号中最宽条纹的动态频率偏移,从而完成被测距离的高精度测量.动态重复频率能够延伸光谱仪探测极限,相应地减小测量盲区,并且基于合成波长也使得测量非模糊范围得到极大的拓展.本文测距系统无需重复频率的锁定,能够摆脱对锁相环等复杂应用模式的依赖,在简化系统的同时借助铷钟提供精准时钟参考,从而进一步提高测量精度.此外,电荷耦合器件成像帧速以及重复频率扫描速度的提升可实现干涉信号的快速采集,弥补传统光谱干涉测量以及腔调谐方式在探测速度上的不足.实验结果表明,本文方法单点测距数据更新率为13.5 Hz,相较于参考数值,在20 m的测量范围内,测量不确定度优于27μm,相对精度为1.35×10^(-6).Frequency combs have given rise to revolutionary progress in a variety of applications.The absolute distance measurement by using frequency comb has been developing rapidly in recent years.In this paper,a method of rapid ranging via the dynamic chirped pulse interferometry is proposed.With the sweeping of comb spacing,the dynamic frequency offset of the sparsest stripes can be obtained in the chirped pulse interferometry,which leads to the cues about the measuring distance.The introduction of dynamic comb spacing can effectively reduce the dead zone of the optical spectrum analyzer.Based on the theory of synthetic wavelength,the multiple repetition frequency can also realize a great non-ambiguity range.In the measuring system,there is no need to lock the repetition rate any more,thereby removing the dependency of bulky phase-locking circuits,and simplifying the system.Besides,the rubidium clock brings the accurate clock reference in the system.Hence,the repetition rate and camera can perform strict synchronization.Considering the improvements of imaging frame rate and the scanning speed of repetition rates,the changed spectral interferograms can be obtained rapidly,and thus compensating for the speed deficiency of dispersive interferometry and cavity tuning.The experimental results show that elapsed time is 74.1 ms for the single time,corresponding to a data updating rate of 13.5 Hz.In a range of 20 m,the measurement uncertainty is well within 27μm,i.e.the relative precision of 1.35×10^(–6).

关 键 词：绝对距离测量 动态光学频率梳 啁啾脉冲干涉 

分 类 号：O436.1[机械工程—光学工程]