Radiation scanning system

摘要

A radiation scanning system which includes a radiation detector located at the focus of an objective lens element and a radiation scanning element arranged to scan radiation emanating from a field of view across the detector. The radiation forms a primary pupil, and one of said elements is located at a conjugate pupil formed by an optical assembly which comprises first and second concave part-spherical reflectors respectively having their centers of curvature substantially optically coincident with the locations of the primary pupil and the conjugate pupil, and a convex reflector substantially coincident with the locus of the focii formed by parallel beams of radiation emanating from the primary pupil and incident upon the first concave reflector.