LENS HAVING A CIRCUMFERENTIAL FIELD OF VIEW

摘要

A lens having an axis of symmetry, including a transparent circumferential surface, circumferentially extending about the axis of symmetry, the transparent surface having optical power in planes which include the axis of symmetry, a first reflective surface, symmetric with respect to the axis of symmetry and being operative to reflect light passing through the transparent surface and a second reflective surface, symmetric with respect to the axis of symmetry and axially spaced from the transparent surface and being operative to reflect light reflected by the first reflective surface.