Active polarization control servo and method

Abstract From the Canadian patent

Abstract of the Disclosure, An active polarization control system which provides two dimensional, optical waveguide birefringence modulation provides polarization control in, systems such as fiber optic rotation sensors and coherent fiber optic communications systems without the necessity of using costly polarization preserving fiber. In a rotation sensor the signal output from the sensing loop is used to form feedback signals for correcting polarization state errors. The feedback signals are used to provide the corrective voltage applied to two banks of orthogonally modulated birefringence transducers situated inside the rotation sensing loop. In a coherent fiber optic communications …