Alignment of the SPHERE-ZIMPOL imaging polarimeter

ZIMPOL is the high contrast imaging polarimeter subsystem of the ESO SPHERE instrument. ZIMPOL is dedicated to detect the very faint reflected and hence polarized visible light from extrasolar planets. ZIMPOL is located behind an extreme 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 into SPHERE by the aid of an alignment unit. The field selecting tip/tilt mirror alignment and it’s requirement for perpendicularity 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.