Rotation and acceleration sensor based on nondegenerate ring lasers
AssigneeDigital Optics Technologies, Inc.
InventorsSelim M. Shahriar, Nicholas J. Condon, Devin J. Hileman, Shih C. Tseng
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Abstract
Ring laser gyroscopes, in which rotation is detected by the Sagnac effect between counterpropagating lasers, are in common use in navigation applications. The invention disclosed here uses lasers operating at different frequencies; the resulting device is referred to as a Nondegenerate Ring Laser Gyroscope (NRLG). The invention disclosed here also incorporates an acceleration-sensing element that modifies the path length of the ring lasers in the gyroscope, the effects of which on the output of the gyroscope can be separated from those of rotation. The resulting composite device is a Nondegnerate Ring Laser Gyroscope/Accelerometer (NRLGA).
Claims12
A device comprising:
- two counter propagating ring lasers sharing a common cavity, wherein the lasers are generated using a resonant Raman process in an alkali metal vapor, wherein the cavity contains a mirror mounted on an acceleration-sensitive element to generate acceleration detection;
- and
- an optical pump module, wherein the optical pump module includes a first 780 nm Distributed Bragg Reflector laser and a second 780 nm DBR laser, wherein the output of the first 780 nm DBR laser is locked to an 85Rb absorption transition, wherein the output of the second 780 nm DBR laser is locked to an 87Rb absorption transition, wherein the output of the lasers is passed through a heated rubidium vapor cell.
A combined nondegenerate ring laser gyroscope and accelerometer device comprising:
- a clockwise resonant Raman laser pump module;
- a counter clockwise resonant Raman laser pump module;
- an optical pump module;
- a ring laser module including a laser gain medium, wherein the laser gain medium is the vapor of an alkali metal element;
- and
- a readout module,
- wherein the output from the clockwise resonant Raman laser pump module and the counter clockwise resonant Raman laser pump module combine with one of the two optical pump outputs on a dichroic beam combiner to form a combined set of beams,
- wherein the ring laser module receives the combined set of beams in a single cavity, wherein the ring laser module generates a pair of counter-propagating resonant Raman lasers in a single cavity, wherein the cavity contains a mirror mounted on an acceleration-sensitive element to generate acceleration detection,
- wherein the readout module receives the output of the ring laser module to produce a desired rotation and acceleration signal,
- wherein the optical pump module includes a first 780 nm Distributed Bragg Reflector laser and a second 780 nm DBR laser, wherein the output of the first 780 nm DBR laser is locked to an 85Rb absorption transition, wherein the output of the second 780 nm DBR laser is locked to an 87Rb absorption transition, wherein the output of the lasers is passed through a heated rubidium vapor cell.
Dependencies are inferred from the claim text.