Resources Contact Us Home
Solid medium optical ring laser rotation sensor

Image Number 3 for United States Patent #5408492.

An optical rotation sensor comprises a light amplification stimulated emission ring laser formed in a solid medium is provided with phase modulator devices which produce push-pull phase modulation of counterpropagating optical waves in the ring thereby enhancing bidirectional lasing in single longitudinal modes in each direction. A frequency selective output coupler couples a predetermined portion of the optical energy at the lasing frequency from the ring to an output waveguide. A substantially U-shaped output waveguide having legs extending away from the ring in opposite directions and toward a common position. Clockwise and counterclockwise light waves are coupled from the ring to the two separate legs of the output waveguide and are directed to the common position to create an interfering light pattern on photodetector apparatus. The interfering light pattern is indicative of the rate of rotation, as defined by the Sagnac effect. Signal processing circuitry connected to the detector derives navigation and flight control information from the detector. In one embodiment, the ring laser and input and output couplers are implemented in a rare earth-doped lithium niobate substrate. In another embodiment, the ring laser and the input and output waveguides are implemented in rare earth-doped optical fibers. In a further embodiment, the ring laser and input and output couplers as well as the phase modulators and the photodetector apparatus are implemented in a single semiconductor substrate and gain electrically supplied to the ring laser.

  Recently Added Patents
Photosensitive drum unit, assembling method therefor, and disassembling method therefor
Flexible macroblock ordering and arbitrary slice ordering apparatus, system, and method
Semiconductor device and electronic apparatus
Method for inspecting bolts
Swirler for gas turbine engine fuel injector
Providing associations between objects and individuals associated with relevant media items
Information processing apparatus and locus data recognition method
  Randomly Featured Patents
System and method for static and dynamic load analyses of communication network
Shutter mechanism
Broadhead arrow head
Reset recovery in a microprocessor controlled device
System and method for creating a wireless picocell
Method for producing compound semiconductors and apparatus therefor
Abatement of hydrogen sulfide with epoxides
Process for the preparation of optically and chemically highly pure (R)- or (S)-.alpha.-hydroxycarboxylic acids
Double-talk and path change detection using a matrix of correlation coefficients
Protective shipper