Mirror facet tracker using spherical mirrors

摘要

An all mirror facet tracking system including first and second spherical mirrors. Both of the mirrors can be located along the same system axis on opposite sides of a rotating multi-faceted polygon which has its axis of rotation on the system axis. To reduce coma, the spherical mirrors are located along orthogonal system axes and a flat folding mirror is provided between the two spherical mirrors to reduce the angle of incidence of the chief ray with the second spherical mirror.