Fiber ring interferometer using a Kerr medium optical fiber loop

摘要

The invention comprises an interferometer for detecting rotation in which a single light beam is split by a first polarizing beam splitter into two linearly, orthogonally polarized beams and introduced to opposite ends of a linear polarization maintaining fiber optic loop formed of a Kerr medium optical fiber material having a 90° twist therein. Upon exiting the opposite ends of the loop, the two beams are recombined by the first polarizing beam splitter into a single beam. The recombined light beam is seperated from the input light beam and is passed through a quarter-wave plate which converts the linear polarization to circular polarization. The circularly polarized beam is then passed through a second polarizing beam splitter to form two separate beams of distinct intensity dependent upon the two distinct circular polarizations contained in the incident beam. The two light beams are introduced to a balanced detector whereupon the difference in intensity of the two light beams is detected. This difference in intensity indicates the rotational direction and velocity of the fiber optic loop, thus allowing the device to be used to detect rotation.