Thermal and broadband infrared optics continues to see an increased demand from both the military and commercial market, while maintaining a desire for a reduction in size and weight and cost (SWaPc). This has led to the development of many new potential optical materials from various sources . Most of these new materials are chalcogenide glasses due to their broad transmission window and potential for hot forming such as precision glass molding. When evaluating these materials from an optical design perspective, there are a few optimal materials that continue to appear in different designs. This work demonstrates why these materials are attractive optically, and reports on the thermal and optical properties of these materials that affect their design and manufacturing.

Linear Variable Filters (LVF) bandpass filters provide a gradient in passband wavelength along one axis and constant center wavelength along the orthogonal axis. Infrared LVF filters used to discriminate wavelength provide a hyperspectral capability to the infrared imager which is light weight and rugged. By exploiting filter harmonics, dual band LVF filters have been demonstrated for the mid and far infrared spectral regions.