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Strehl ratio and visibility in long-baseline stellar interferometry.
Optics Letters
|October 28, 2009
Summary
Adaptive optics Strehl ratio (S) and interferometry visibility (V) are compared. For high Strehl ratios, V approximately equals S, but at low Strehl ratios, visibility is underestimated by the Strehl ratio.
Area of Science:
- Astronomy and Astrophysics
- Optical Engineering
Background:
- Adaptive optics (AO) and optical interferometry are key astronomical techniques.
- Strehl ratio (S) is standard in AO, while visibility (V) is crucial for interferometry.
Purpose of the Study:
- Investigate the relationship between Strehl ratio (S) and visibility (V).
- Determine how well S predicts V in different atmospheric turbulence conditions.
Main Methods:
- Simulations of atmospheric turbulence.
- Analytical formulation of the relationship between S and V.
- Analysis under Kolmogorov turbulence assumptions.
Main Results:
- For high Strehl ratios (S), visibility (V) is approximately equal to S.
- At low Strehl ratios, S underestimates the actual V.
- Discrepancy increases as Strehl ratio decreases.
Conclusions:
- The Strehl ratio is a reliable indicator of visibility only under high Strehl conditions.
- Interferometry practitioners should be cautious when using S to infer V at low Strehl ratios.
- Further research may refine the relationship for low Strehl regimes.
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