FN Archimer Export Format
PT C
TI Adapting the pyramid wavefront sensor for pupil fragmentation of the ELT class telescopes
BT 
AF LEVRAUD, Nicolas
   CHAMBOULEYRON, Vincent
   FAUVARQUE, Olivier
   CISSE, Mahawa
   SAUVAGE, Jean-Francois
   NEICHEL, Benoit
   BOND, Charlotte
   PINNA, Enrico
   ESPOSITO, Simone
   SCHWARTZ, Noah
   FUSCO, Thierry
AS 1:1,2,4;2:1,2;3:3;4:1,2;5:1,2;6:2;7:5;8:4;9:4;10:5;11:1,2;
FF 1:;2:;3:PDG-REM-RDT-LDCM;4:;5:;6:;7:;8:;9:;10:;11:;
C1 DOTA, ONERA, Univ. Paris Saclay (France)
   Aix Marseille Univ., CNRS, CNES, Lab. d'Astrophysique de Marseille (France)
   Ifremer, Lab. Detection, Capteurs et Mesures (LDCM) (France)
   INAF, Osservatorio Astrofisico di Arcetri (Italy)
   UK Astronomy Technology Ctr. (United Kingdom)
C2 ONERA, FRANCE
   UNIV AIX MARSEILLE, FRANCE
   IFREMER, FRANCE
   INAF OSSERV ASTROFIS ARCETRI, ITALY
   UK ASTRON TECHNOL CTR, UK
SI BREST
SE PDG-REM-RDT-LDCM
IN WOS Ifremer UPR
   copubli-france
   copubli-europe
   copubli-univ-france
UR https://archimer.ifremer.fr/doc/00801/91285/97065.pdf
LA English
DT Proceedings paper
DE ;Segmented Telescope;Pyramid Wavefront Sensor;ELT
AB The next generation of Extremely Large Telescope (24 to 39m diameter) will suffer from the so-called "pupil fragmentation" problem. Due to their pupil shape complexity (segmentation, large spiders ... ), some differential pistons may appear between some isolated part of the full pupil during the observations. Although classical AO system will be able to correct for turbulence effects, they will be blind to this specific telescope induced perturbations. Hence, such differential piston, a.k.a petal modes, will prevent to reach the diffraction limit of the telescope and ultimately will represent the main limitation of AO-assisted observation with an ELT. In this work we analyse the spatial structure of these petal modes and how it affects the ability of a Pyramid Wavefront sensor to sense them. Then we propose a variation around the classical Pyramid concept for increasing the WFS sensitivity to this particular modes. Nevertheless, We show that one single WFS can not accurately and simultaneously measure turbulence and petal modes. We propose a double path wavefront sensor scheme to solve this problem. We show that such a scheme,associated to a spatial filtering of residual turbulence in the second WFS path dedicated to petal mode sensing, allows to fully measure and correct for both turbulence and fragmentation effects and will eventually restore the full capability and spatial resolution of the future ELT. 
PY 2022
CT Proceedings SPIE. Volume 12185, Adaptive Optics Systems VIII, 1218559 (29 August 2022), 11p. + poster
DI 10.1117/12.2629861
ID 91285
ER

EF