Focal-plane-assisted pyramid wavefront sensor: Enabling frame-by-frame optical gain tracking

@article{Chambouleyron2021FocalplaneassistedPW,
  title={Focal-plane-assisted pyramid wavefront sensor: Enabling frame-by-frame optical gain tracking},
  author={Vincent Chambouleyron and Olivier Fauvarque and Jean-François Sauvage and Benoı̂t Neichel and Thierry Fusco},
  journal={Astronomy \& Astrophysics},
  year={2021}
}
Aims. With its high sensitivity, the pyramid wavefront sensor (PyWFS) is becoming an advantageous sensor for astronomical adaptive optics (AO) systems. However, this sensor exhibits significant non-linear behaviours leading to challenging AO control issues. Methods. In order to mitigate these effects, we propose to use in addition to the classical pyramid sensor a focal plane image combined with a convolutive description of the sensor to fast track the PyWFS non-linearities, the so-called… 

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