Method and apparatus for optical isolation

摘要

An optical isolator and circular polarizer are used in combination to optically isolate specular and diffuse reflections which result when a forward traveling radiation beam encounters an optical or non-optical boundary surface. The forward traveling radiation beam is linearly polarized with a linear polarizer such that its plane of linear polarization is aligned with a first polarization axis, then the axis of linear polarization is rotated to a second polarization axis with a polarization rotator and finally the linearly polarized forward traveling beam is circularly polarized with a quarter wave retarder.