基于光谱标定的光频扫描干涉绝对测距方法  

Frequency Scanning Interferometry Absolute Distance Measurement Method Based on Optical Spectrum Calibration

作　　者：尚岳 吴腾飞[1] 林嘉睿[1] 杨凌辉[1] 周强 邾继贵[1] Shang Yue;Wu Tengfei;Lin Jiarui;Yang Linghui;Zhou Qiang;Zhu Jigui(State Key Laboratory of Precision Measurement Technology and Instruments,Tianjin University,Tianjin 300072,China)

机构地区：[1]天津大学精密测试技术及仪器国家重点实验室,天津300072

出　　处：《光学学报》2022年第12期158-168,共11页Acta Optica Sinica

基　　金：国家自然科学基金(52127810,51835007,51721003)。

摘　　要：光频扫描干涉(FSI)绝对测距技术具有精度高、灵敏度高等优点,受到了大型装备制造领域的广泛关注。为获得更高的测距精度,FSI系统中往往需要通过构建光纤辅助干涉仪以实现对光频变化的精密监测。然而,受环境因素以及色散效应的影响,光纤辅助干涉仪的光程难以在测量过程中维持稳定,导致测量精度严重下降。针对这一问题,提出了一种基于光谱标定的FSI绝对测距方法,采用氰化氢(HCN)气体的吸收光谱特征为FSI系统辅助干涉仪光程的在位快速标定提供稳定、精确的光频参考。提出了一种色散失配误差的快速补偿方法以消除光纤辅助干涉仪引入的色散失配误差对测量结果的影响。为验证上述方法的有效性,在20 m的距离上与商用干涉仪进行精度对比实验。实验结果表明,在测量范围内该系统的最大测距偏差小于50μm,测量重复性优于±4μm。With high precision and sensitivity,frequency scanning interferometry(FSI)absolute distance measurement technique is getting more and more attention in the field of large-scale equipment manufacturing.Building an optical fiber auxiliary interferometer in an FSI system to realize the precise monitoring of optical frequency changes is necessary for achieving higher ranging accuracy.However,the stability of optical path of the auxiliary interferometer is limited by the environmental factors and dispersion effect,which would reduce the accuracy seriously.An optical spectrum calibration based FSI absolute distance measurement method is proposed in this paper for this problem.The optical path of the auxiliary interferometer in the FSI system is calibrated in situ with the help of the absorption spectrum of hydrogen cyanide(HCN)to provide stable and accurate optical frequency reference.What’s more,a fast compensation method for dispersion mismatch error is proposed to eliminate the influence of dispersion mismatch effect caused by the fiber optic assisted interferometer on measurement results.The proposed method is verified by comparison experiments with commercial interferometer at a range of 20 m.The result shows that the largest ranging deviation of the system is less than 50μm,and the repeatability is better than±4μm.

关 键 词：测量 光频扫描干涉 绝对距离测量 吸收光谱 色散效应 

分 类 号：TH741[机械工程—光学工程]