Field guide to terahertz sources detectors and optics The region of the electromagnetic spectrum between microwaves and infrared radiation has come to be known as the THz gap mainly due to the lack of readily available laboratory sources and detectors. Potential applications however particularly in medicine security and communications have led to increased activity by the mainstream physics and engineering community in recent years. The primary objective of this SPIE Field Guide is to provide the reader with a concise description of the quasi optical techniques used to design THz systems as well as the basic principles of operation of the most common THz components in use today Introduction THz sources THz detectors THz optics THz applications Equation summary Bibliography Index