Closed-loop focal plane wavefront control with the SCExAO instrument

  title={Closed-loop focal plane wavefront control with the SCExAO instrument},
  author={Frantz Martinache and Nemanja Jovanovic and Olivier Guyon},
  journal={arXiv: Instrumentation and Methods for Astrophysics},
This article describes the implementation of a focal plane based wavefront control loop on the high-contrast imaging instrument SCExAO (Subaru Coronagraphic Extreme Adaptive Optics). The sensor relies on the Fourier analysis of conventional focal-plane images acquired after an asymmetric mask is introduced in the pupil of the instrument. This absolute sensor is used here in a closed-loop to compensate the non-common path errors that normally affects any imaging system relying on an upstream… 
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