Compact, Broadband Infrared Spectrometer

Large-aperture, wide-angle, broad-band infrared spectrometer compact and light in weight. Based on double-pass version of Schmidt optical system that acts as both collimator and camera. Because optical system contained in piece of solid glass, it is mechanically and thermally stable. System made of water-free fused silica to minimize absorption of infrared radiation. Although in principle made from single, solid piece, in practice made in two pieces cemented together. Fabrication easier and simpler if more cemented surfaces used so each optical surface grounded and polished like single lens element.