title: Unit magnification optical system.
abstract: A simple self-conjugate optical arrangement, originally proposed by Dyson, consists of a spherical mirror and a plano-convex lens. Despite the fact that all the Seidel aberrations are corrected, the field coverage is severely limited by higher order tangential astigmatism. This paper discusses modifications to improve the field coverage. It also treats the creation of internal reflecting surfaces to separate the object and image planes. Finally a few possible applications are discussed, including one to the creation of a high speed spectrograph.
authors.forename: S
authors.initials: S
authors.lastname: Rosin