Telescope wavefront control at ELT

lundi 18 novembre 2019, par Henri Bonnet (ESO)

Jeudi 12 décembre 2019 à 16h00 , Lieu : Salle de conférence du bâtiment 17

The ESO Extremely Large Telescope will be exposed to large amplitude dynamic perturbations in a broad range of spatial and temporal scales.

The task of the Telescope Control System is to bring the quality of the beam delivered to the instruments within the capture range of their post-focal Adaptive Optics systems. The Phasing and Diagnostic Station, located at the folded Nasmyth focus, below the optical axis, hosts the sky metrologies used in the telescope engineering mode to validate the wavefront performance at the interface to the instruments. The talk will present the baseline scenario for the phasing of the primary mirror and the telescope adaptive optics mode, based on a pyramid wavefront sensor operated in the near infrared. This mode encompasses background algorithms in charge of maintaining the alignments and the connection between the sectors of the pupil.