ABSTRACT
Nonimaging concentrators and illuminators have several current and some potential applications. It is best to explain the general concept of a nonimaging concentrator by highlighting one of its applications: the utilization of solar energy. The particular kind of nonimaging concentrator that has given rise to the great developments was originally conceived as a device for collecting as much light as possible from a luminous volume over a certain range of solid angles and sending it onto the cathode of a photomultiplier. Nonimaging collectors are also used in illumination. The source (a filament, an LED, etc.) in general emits in a wide angular spread at low intensity, and the problem consists of designing an optical device that efficiently collimates the radiation so it is emitted in a certain angular emitting region, which is smaller than the angular emitting region of the source. The chapter also presents an overview of the key concepts discussed in this book.
