Scanning Telescope For The Advanced Polarized Infrared Imaging Sensor (Apiris)

An advanced polarized infra-red imaging sensor (APIRIS) has been designed and prototyped to acquire the polarization signature of targets in the far IR (8 - 12 microns) region with a field of view 4 degree(s) X 3 degree(s). The design (optical and optomechanical), fabrication and assembly issues of the scanning telescope for the APIRIS are discussed in this paper. The telescope is designed for diffraction limited performance using germanium lenses and Zerodur fold mirrors to minimize overall size of the telescope. The tolerance budgeting and thermal sensitivity analysis are also presented.