频率扫描干涉法绝对测距中运动误差的补偿研究  

Movement Error Compensation in Frequency Scanning Interferometry for Absolute Distance Measurement

作　　者：李志栋[1] 江月松[1] 桑峰[1] 王林春[1] 邓士光[1] 辛遥[1] 郭泾平[2] 

机构地区：[1]北京航空航天大学电子信息工程学院,北京100191 [2]中国空间技术研究院,北京100094

出　　处：《光学学报》2011年第3期144-149,共6页Acta Optica Sinica

基　　金：中国科学院知识创新项目(AA20090024)资助课题

摘　　要：在频率扫描干涉法绝对距离测量过程中,目标的运动会对测量结果引入误差,经推导发现运动误差与激光扫频终点频率以及扫频过程中的光程差位移量有关。前者可直接通过高精度波长计测量,对于后者,提出了外差干涉频分复用技术,设计了一种新的频率扫描距离测量干涉仪,可同时实现目标绝对距离和光程差位移量的测量,通过剔除与扫频终点频率和光程差位移量有关的误差相位偏移量后即可实现运动补偿。分析了该绝对距离测量系统的可行性和运动补偿的不确定度,并对测量精度进行仿真验证。结果表明该方法快速有效,在较快速运动目标测距时可实现对纳米量级光程差位移量的测量。在几十米距离范围内,当频率扫描范围达到100 GHz时该补偿方法引入的误差约为几十微米。Target movements can introduce movement error in absolute distance measurement using frequency-scanning interferometry.It is deduced that movement error depends on the optical path difference displacements during the scan and the laser frequency at the endpoint of the scan.The former can be obtained directly by using a high-accuracy wave meter;for the latter,heterodyne interference frequency division multiplexing technique is proposed and a novel frequency-scanning interferometer for absolute distance is designed to achieve simultaneous measurement of the absolute distance and the optical path difference displacements.Movement error-compensation can be fulfilled by eliminating the error phase offset related to laser frequency at the endpoint of the scan and the optical path difference displacements.Theoretical analysis of the feasibility of the system and the uncertainty of movement compensation with precision measurement simulation indicate that the compensation method is efficient and effective.Optical path difference displacements measurement can reach nanometer level for rather high-speed target.The error introduced by movement compensation is tens of microns with the frequency-scanning range of 100 GHz at tens of meters distance range.

关 键 词：激光光学 运动误差补偿 精度测量仿真 频率扫描干涉法 绝对距离 

分 类 号：TN249[电子电信—物理电子学]