PASSIVE TOPOLOGICALLY BIASED SAGNAC INTERFEROMETER AS A ROTATIONAL SENSOR CAPABLE OF SENSING MAGNITUDE AND DIRECTION OF ROTATION

Many optical gyroscopes are based on an optical Sagnac interferometer configuration including various interferometric fiber-optic gyroscopes (IFOG) to measure magnitude and direction of rotation. IFOGs require active phase modulation in their fiber coil to decipher direction of rotation. This patent document discloses a new type of IFOGs that utilizes a passive topological (also known as geometric) phase shift to sense magnitude and direction of rotation without requiring active phase modulation.