Abstract: An optical device comprises a dichroic beamsplitter for splitting an object beam into a reflected beam having a first waveband and a transmitted beam having a second waveband; an astigmatism-correcting lens element, disposed in the optical path of the transmitted beam; and a coma-correcting lens element, disposed in the optical path of the transmitted beam.

Abstract: An optical system having a selected one of a pair of fields of view. The optical system includes a primary reflector; a secondary reflector; a refractive optical system; and a drive. The drive orients the secondary reflector to a first region in optical alignment with the primary reflector to provide the optical system with one of the pair of fields of view and for reorienting the secondary reflector to a second region out of optical alignment with the primary reflector and orienting the refractive optical system at the first region to provide a refractive optical system with a second one of the pair of fields of view. The optical system includes a detector and a second refractive optical system disposed between the first region and the detector. The detector comprises an array of detector elements.