Alignment of the SPHERE-ZIMPOL imaging polarimeter

摘要

ZIMPOL is the high contrast imaging polarimeter subsystem of the ESO SPHERE instrument. ZIMPOL is dedicated todetect the very faint reflected and hence polarized visible light from extrasolar planets. ZIMPOL is located behind anextreme AO system (SAXO) and a stellar coronagraph. SPHERE is foreseen to have first light at the VLT early 2013.ZIMPOL is currently integrated in the SPHERE system and in testing phase.We describe the alignment strategy and the results of the ZIMPOL system and the related alignment of ZIMPOL intoSPHERE by the aid of an alignment unit. The field selecting tip/tilt mirror alignment and it’s requirement forperpendicularity to the two detectors is described. The test setup of the polarimetric components is described.SPHERE is an instrument designed and built by a consortium consisting of IPAG, MPIA, LAM, LESIA, Fizeau, INAF,Observatoire de Genève, ETH, NOVA, ONERA and ASTRON in collaboration with ESO.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.