Hans Wolter
Hans Wolter was a German physicist who designed an aplanatic system of angle of [incidence (optics)|grazing incidence] mirrors that satisfied the Abbe sine condition.
Wolter showed such a system could be produced using a combination of a paraboloid with either a hyperboloid or ellipsoid secondary. The three simplest designs are outlined and are known as Wolter telescopes of types I, II and III.