Optically pumped submillimeter laser heterodyne receivers: astrophysical observations and recent technical developments

The use of optically pumped submillimeter lasers as a local oscillator source is discussed. The principle of operation of submillimeter lasers in heterodyne systems is examined, and a detailed description of an airborne laser receiver system is given as an example. Some ground-based and airborne laser heterodyne astrophysical observations are then reviewed. Advances in submillimeter technology, especially the miniaturization of the CW CO/sub 2/ pump laser, are discussed, and advances in submillimeter lasers designs are briefly addressed.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>