High-precision frequency sweeping interferometry for absolute distance measurement using a tunable laser with sweeping range of 88 GHz
| Autor: | Wen Wang, Kefei Hei, Shi Guang, Nandini Bhattacharya |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
Physics
Accuracy and precision business.industry Applied Mathematics System of measurement Phase (waves) Interference (wave propagation) Laser 01 natural sciences Standard deviation law.invention 010309 optics Interferometry Optics frequency sweeping interferometry law 0103 physical sciences absolute distance measurement laser distance measurement business Instrumentation Engineering (miscellaneous) Tunable laser |
| Zdroj: | Measurement Science and Technology, 31(4) |
| ISSN: | 0957-0233 |
| Popis: | Distance measurement using frequency sweeping interferometry (FSI) is an absolute distance measurement technique that allows for high accuracy over long distances. Notwithstanding, the measurement accuracy is affected by laser sweeping nonlinearity and limited sweeping range. In this work, an optimized post-processing linearization method is demonstrated to realize high accuracy arbitrary distance measurement using a laser with small modulation range. The interference signal is sparsely resampled to eliminate the influence of the sweeping nonlinearity, and the absolute distance is obtained by analyzing the phase of the resampled signal. In the measurement system, a high finesse Fabry-Perot (F-P) cavity placed in vacuum is used as the measurement reference, so the effect of dispersion mismatch is negligible. Moreover, the distance measurement result is determined by the linear fit of the phase of each resampled point. Therefore, the influence of target vibration and other external random noise can be partially eliminated, and the reliability of the result is high. In the experiment, the sweeping range of the laser source is only 88 GHz. Comparing with a fringe counting interferometer, the standard deviation of the residual errors is 34 μm within a distance of 6.7 m. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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