Waveguide (integrated) optics. Classification and definitions

A classification is proposed of waveguide-optics (integrated-optics) systems developed up to now in the Soviet Union and abroad. The classification is based on the function of the system and its design features. Several new definitions are also suggested (structure element, functional systems of different classes, spatial zone of a system) and these are used to develop the classification. This classification makes it possible to consider in a systematic manner the systems developed so far, to forecast future systems, and to assign a unique index to a given system, independent of its various applications.