Patent ID: 7505192

Claim:
An optical apparatus for operating on a polarization state of a light beam, said optical apparatus comprising: a) a compound tri-state non-reciprocal rotator placed in the optical path of said light beam and having: 1) a first Faraday rotator for rotating said polarization state into one of two partially rotated states at angles +α, −α, wherein α=22.5°; 2) a second Faraday rotator in communication with said first Faraday rotator for rotating said polarization state from said one of two partially rotated states at angles +α, −α into one of three fully rotated states at angles +2α, 0, −2α; b) a polarization selection means for guiding light in said three fully rotated states to generate a tri-state output comprising two distinct output beams and an overlapping pair of output beams.