25 April 2017 Speckle statistics in adaptive optics images at visible wavelengths
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Residual speckles in adaptive optics (AO) images represent a well-known limitation on the achievement of the contrast needed for faint source detection. Speckles in AO imagery can be the result of either residual atmospheric aberrations, not corrected by the AO, or slowly evolving aberrations induced by the optical system. We take advantage of the high temporal cadence (1 ms) of the data acquired by the System for Coronagraphy with High-order Adaptive Optics from R to K bands-VIS forerunner experiment at the Large Binocular Telescope to characterize the AO residual speckles at visible wavelengths. An accurate knowledge of the speckle pattern and its dynamics is of paramount importance for the application of methods aimed at their mitigation. By means of both an automatic identification software and information theory, we study the main statistical properties of AO residuals and their dynamics. We therefore provide a speckle characterization that can be incorporated into numerical simulations to increase their realism and to optimize the performances of both real-time and postprocessing techniques aimed at the reduction of the speckle noise.
© 2017 Society of Photo-Optical Instrumentation Engineers (SPIE)
Marco Stangalini, Fernando Pedichini, Enrico Pinna, Julian C. Christou, John Hill, Alfio Puglisi, Vanessa P Bailey, Mauro Centrone, Dario Del Moro, Simone Esposito, Fabrizio Fiore, Emanuele Giallongo, Phil Hinz, Amali Vaz, "Speckle statistics in adaptive optics images at visible wavelengths," Journal of Astronomical Telescopes, Instruments, and Systems 3(2), 025001 (25 April 2017). https://doi.org/10.1117/1.JATIS.3.2.025001 . Submission: Received: 14 October 2016; Accepted: 10 April 2017
Received: 14 October 2016; Accepted: 10 April 2017; Published: 25 April 2017


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