Today's SWIR, MWIR, LWIR and multispectral technologies cover a wide range of commercial and military applications and continue to rapidly expand in almost every aspect of our lives. This Field Guide focuses on the most common infrared crystals and glasses used in these systems, from their manufacturing methods through modern optical fabrication technologies to the end-use applications. Detailed optical, crystallographic, mechanical, chemical, and thermal properties of the most popular infrared materials are reviewed in detail along with process flows and relative comparisons. The Field Guide to Infrared Optical Materials provides a concise and convenient resource for those interested in the materials used in infrared optical systems