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Journal of the Optical Society of America A

Journal of the Optical Society of America A


  • Editor: Franco Gori
  • Vol. 27, Iss. 11 — Nov. 1, 2010
  • pp: A1–A8

Optimal reconstruction for closed-loop ground-layer adaptive optics with elongated spots

Clémentine Béchet, Michel Tallon, Isabelle Tallon-Bosc, Éric Thiébaut, Miska Le Louarn, and Richard M. Clare  »View Author Affiliations

JOSA A, Vol. 27, Issue 11, pp. A1-A8 (2010)

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The design of the laser-guide-star-based adaptive optics (AO) systems for the Extremely Large Telescopes requires careful study of the issue of elongated spots produced on Shack–Hartmann wavefront sensors. The importance of a correct modeling of the nonuniformity and correlations of the noise induced by this elongation has already been demonstrated for wavefront reconstruction. We report here on the first (to our knowledge) end-to-end simulations of closed-loop ground-layer AO with laser guide stars with such an improved noise model. The results are compared with the level of performance predicted by a classical noise model for the reconstruction. The performance is studied in terms of ensquared energy and confirms that, thanks to the improved noise model, central or side launching of the lasers does not affect the performance with respect to the laser guide stars’ flux. These two launching schemes also perform similarly whatever the atmospheric turbulence strength.

© 2010 Optical Society of America

OCIS Codes
(010.1080) Atmospheric and oceanic optics : Active or adaptive optics
(120.5050) Instrumentation, measurement, and metrology : Phase measurement
(350.1260) Other areas of optics : Astronomical optics

Original Manuscript: January 15, 2010
Manuscript Accepted: March 27, 2010
Published: May 17, 2010

Clémentine Béchet, Michel Tallon, Isabelle Tallon-Bosc, Éric Thiébaut, Miska Le Louarn, and Richard M. Clare, "Optimal reconstruction for closed-loop ground-layer adaptive optics with elongated spots," J. Opt. Soc. Am. A 27, A1-A8 (2010)

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