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Published on: May 29, 2019
Optical path length fluctuations in the atmosphere
G N Gibson1, J Heyman, J Lugten
1University of California, Physics Department, Berkeley, California 94720, USA.
Applied Optics
|December 1, 1984
Summary
Atmospheric fluctuations impact laser interferometer distance measurements. This study quantifies optical path length variations in open air, crucial for improving precision in dimensional monitoring.
Area of Science:
- Optics
- Metrology
- Atmospheric Physics
Background:
- Laser interferometry is increasingly used for precise distance measurements.
- Atmospheric conditions significantly affect optical path lengths, impacting measurement accuracy.
Purpose of the Study:
- To evaluate the precision of dimensional monitoring using interferometry in open air.
- To analyze optical path length fluctuations under good atmospheric conditions.
Main Methods:
- Measurement and analysis of optical path length fluctuations over one-meter distances.
- Investigation of temporal characteristics and spatial correlations of these fluctuations.
Main Results:
- Quantification of the size and time scale of optical path length fluctuations.
- Analysis of correlations between fluctuations in adjacent optical paths.
Conclusions:
- Understanding atmospheric effects is vital for enhancing the precision of interferometric distance measurements.
- The study provides data for developing compensation strategies against atmospheric disturbances.
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