Optical design of CPAPIR, a cryogenic IR camera for OMM

The optical design of the wide-field infrared camera CPAPIR (Camera PAnoramique Proche InfraRouge) for the Mont Megantic Observatory (OMM) has been completed. CPAPIR will be a unique wide-field camera at the OMM. It has a full field of view of 0.71 degrees, an instantaneous field of view of 0.88 arc-seconds, and a spectral coverage of 0.85 - 2.5 μm. The camera is operated under vacuum and at cryogenic temperature. The performance (image quality, vignetting, cold stop efficiency, ghost analysis and tolerancing) of CPAPIR has been optimized at cold temperature using cryogenic indices of refraction and coefficients of thermal.