Phase-Induced Amplitude Apodization on centrally obscured pupils: design and first laboratory demonstration for the Subaru Telescope pupil

A B ST R A C T High contrast coronagraphic im aging ischallenging fortelescopes with centralob- structionsandthickspidervanes,suchastheSubaruTelescope.W epresentinthispaper therstlaboratory dem onstration ofa high eciency PIAA-typecoronagraph on such a pupil,using coronagraphic optics which willbe part ofthe Subaru Coronagraphic Extrem e-AO (SCExAO)system currently underassem bly. Losslesspupilapodization isperform ed by a setofaspheric PIAA lensesspecically designed to also rem ove the pupil'scentralobstruction,coupled with a SpiderRem ovalPlate(SRP)which rem oves spidervanesby translating fourpartsofthepupilwith tilted plane-parallelplates.An "inverse-PIAA" system ,located after the coronagraphic focalplane m ask,is used to rem ove o�-axisaberrationsand delivera wideeld ofview. Ourresults validate the concept adopted for the SCExAO system ,and show that the Subaru Telescope pupilcan properly be apodized forhigh contrastcoronagraphic im aging as close as � 1 �=D with no loss ofsensitivity. W e also verify that o�-axis aberrations in the system are in agreem ent with theory,and that the inverse PIAA system recoversa wideusableeld ofview forexoplanetdetection and disksim aging. Subjectheadings: instrum entation:adaptiveoptics| techniques:coronagraphy,apodiza- tion

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