Real-time multiframe blind deconvolution of solar images.

The quality of images of the Sun obtained from the ground are severely limited by the perturbing effect of the turbulent Earth's atmosphere. The post-facto correction of the images to compensate for the presence of the atmosphere require the combination of high-order adaptive optics techniques, fast measurements to freeze the turbulent atmosphere and very time consuming blind deconvolution algorithms. Under mild seeing conditions, blind deconvolution algorithms can produce images of astonishing quality. They can be very competitive with those obtained from space, with the huge advantage of the flexibility of the instrumentation thanks to the direct access to the telescope. In this contribution we leverage deep learning techniques to significantly accelerate the blind deconvolution process and produce corrected images at a peak rate of ~100 images per second. We present two different architectures that produce excellent image corrections with noise suppression while maintaining the photometric properties of the images. As a consequence, polarimetric signals can be obtained with standard polarimetric modulation without any significant artifact. With the expected improvements in computer hardware and algorithms, we anticipate that on-site real-time correction of solar images will be possible in the near future.

[1]  R. Casini,et al.  ANALYSIS OF SEEING-INDUCED POLARIZATION CROSS-TALK AND MODULATION SCHEME PERFORMANCE , 2011, 1107.0367.

[2]  L. R. V. D. Voort,et al.  ON FIBRILS AND FIELD LINES: THE NATURE OF Hα FIBRILS IN THE SOLAR CHROMOSPHERE , 2015, 1502.00295.

[3]  Mats G. Lofdahl Multi-frame blind deconvolution with linear equality constraints , 2002, SPIE Optics + Photonics.

[4]  James R. Fienup,et al.  Joint estimation of object and aberrations by using phase diversity , 1992 .

[5]  Solar Hα features with hot onsets - II. A contrail fibril , 2016, 1609.07616.

[6]  Francois Rigaut,et al.  Clear widens the field for observations of the Sun with multi-conjugate adaptive optics , 2017 .

[7]  Mats G. Löfdahl,et al.  Solar Image Restoration By Use Of Multi-frame Blind De-convolution With Multiple Objects And Phase Diversity , 2005 .

[8]  A. Asensio Ramos,et al.  Enhancing SDO/HMI images using deep learning , 2017, ArXiv.

[9]  Yukio Katsukawa,et al.  The Solar Optical Telescope of Solar-B (Hinode): The Optical Telescope Assembly , 2008 .

[10]  J. C. del Toro Iniesta,et al.  The Imaging Magnetograph eXperiment (IMaX) for the Sunrise Balloon-Borne Solar Observatory , 2010, 1009.1095.

[11]  J. T. Hoeksema,et al.  The Helioseismic and Magnetic Imager (HMI) Investigation for the Solar Dynamics Observatory (SDO) , 2012 .

[12]  W. Pesnell,et al.  The Solar Dynamics Observatory (SDO) , 2012 .

[13]  M. Löfdahl,et al.  CRISPRED: A data pipeline for the CRISP imaging spectropolarimeter , 2014, 1406.0202.

[14]  Santiago,et al.  A CATALOG OF VISUAL-LIKE MORPHOLOGIES IN THE 5 CANDELS FIELDS USING DEEP LEARNING , 2015, 1509.05429.

[15]  Alan M. Title,et al.  Preparation of a Dual Wavelength Sequence of High-Resolution Solar Photospheric Images Using Phase Diversity , 1998 .

[16]  J. C. del Toro Iniesta,et al.  Sunrise: INSTRUMENT, MISSION, DATA, AND FIRST RESULTS , 2010, 1008.3460.

[17]  A. Asensio Ramos,et al.  DeepVel: deep learning for the estimation of horizontal velocities at the solar surface , 2017, ArXiv.