This paper summarizes two subjects; one is theoretical development of zoom lenses and another is their configurational advances.ln
the former part, a general zoom equation is presented and its paraxial analysis is, in general, derived. In the latter part, it is
enumerated and analyzed newly developed configurations of zoom lenses, such as a built-in range extender, an electronically
compensated zoomlens, a two-component telephoto type and others.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.