Absolute distance measurements could be achieved by the technique of frequency scanning interferometry (FSI), which could provide a micron-level accuracy over several tens of meters. However, as the scanning range and distance increasing, the measurement accuracy and resolution would be seriously influenced by the dispersion mismatch effect, which is mainly caused by the dispersion difference between optical fiber and air. A dispersion compensation method was proposed in this paper, and the mismatch effect would be suppressed effectively without complicated calculations for each single measurement. The chirp in resampling clock would be corrected with a pre-calibration procedure, and the compensation factor is demonstrated for different distances. A calibration method of dispersion compensation factor is also proposed, and the linear regression residual is employed as the criterion. Then, the compensation method is evaluated by experiments with different spatial distances and scanning ranges. Finally, a 60-m experiment is carried out for accuracy comparison, and the measurement accuracy is better than 15 µm by comparing with commercial interferometers.

中文翻译：

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频率扫描干涉测量色散失配的有效补偿方法

绝对距离测量可以通过频率扫描干涉测量 (FSI) 技术实现，该技术可以在几十米范围内提供微米级精度。然而，随着扫描范围和距离的增加，测量精度和分辨率将受到色散失配效应的严重影响，色散失配效应主要是由光纤和空气之间的色散差异引起的。本文提出了一种色散补偿方法，无需对单次测量进行复杂的计算，即可有效抑制失配效应。重采样时钟中的啁啾将通过预校准程序进行校正，并针对不同距离演示补偿因子。还提出了色散补偿因子的标定方法，并采用线性回归残差作为标准。然后，通过不同空间距离和扫描范围的实验来评估补偿方法。最后进行了60米的精度对比实验，与商用干涉仪相比，测量精度优于15微米。