Faraday Rotator Mirror

An apparatus comprising:

• a polarization beam splitter configured to separate an incoming light beam input at a first port into component light beams having orthogonal polarization directions and directing the component light beams to respective second and third ports of the polarization beam splitter;
• a Faraday rotator positioned between the polarization beam splitter and a first folding mirror such that light beams exiting the second port of the polarization beam splitter are directed through the Faraday rotator to the first folding mirror, and wherein the first folding mirror directs incident light beams from the Faraday rotator to a second folding mirror;
• and
• the second folding mirror positioned between the polarization beam splitter and the first folding mirror such that light beams exiting the third port of the polarization beam splitter are reflected by the second folding mirror to the first folding mirror, and wherein first folding mirror directs incident light beams from the second folding mirror to the Faraday rotator.

A method comprising:

• receiving a light beam, the components of the light beam having random polarization directions;
• separating the light beam into a first beam and a second beam, the first beam following a first path and the second beam following a second path, wherein the first beam and the second beam have orthogonal polarization directions;
• rotating the polarization direction of the first beam and then reflecting the first beam back along the second path;
• reflecting the second beam back along the first path and then rotating the polarization direction of the second beam;
• combining the first beam and the second beam such that the first beam and the second beam have orthogonal polarization directions, providing suppression of error in the rotation of the polarization direction of the first and second beams;
• and
• outputting the combined beam.