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Interferometry through the turbulent atmosphere at an optical path difference of 354 m
R B Herrick1, J R Meyer-Arendt
1Corning Glass Works, Raleigh, North Carolina 27604, USA.
Applied Optics
|January 6, 2010
Summary
Atmospheric turbulence causes fluctuations in the mean refractive index. A modified Michelson interferometer measured these changes over long atmospheric paths, showing decreased fringe stability with increased path length.
Area of Science:
- Atmospheric optics
- Interferometry
- Laser physics
Background:
- Turbulent atmosphere affects optical path.
- Measuring refractive index fluctuations is crucial for understanding atmospheric effects on light propagation.
Purpose of the Study:
- To investigate atmospheric refractive index fluctuations using a modified Michelson interferometer.
- To determine the impact of path length on optical stability in turbulent air.
Main Methods:
- Utilized a modified Michelson interferometer with a stable Helium-Neon (He-Ne) laser.
- Conducted experiments with mirror separations up to 177 meters (354 m optical path difference).
Main Results:
- Achieved distinct interference fringes even at extended path lengths.
- Observed a decrease in spatial fringe stability as optical path length increased.
- Confirmed increasing atmospheric contribution with longer path lengths.
Conclusions:
- The study quantifies the effect of atmospheric turbulence on optical path stability.
- Long-path measurements reveal significant refractive index fluctuations.
- The modified interferometer is effective for studying atmospheric optical phenomena.
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