title: Figure control for a fully segmented telescope mirror.
abstract: A system is described to control the figure of a large telescope primary mirror that is composed of many individual segments. The geometry considered, employing hexagonal mirrors, allows a simple and economical control system. The system is shown to be reliable and effective in continuously maintaining the figure to the precision required for optical astronomy.
authors.forename: T S
authors.initials: TS
authors.lastname: Mast
authors.forename: J E
authors.initials: JE
authors.lastname: Nelson