Optical power measurement of a closed loop fiber optic gyroscope
AssigneeLitton Systems, Inc.
InventorsLeon Kristal, Mark Bowser, Rocco Pennacchio
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Abstract
This disclosure describes fiber optic gyroscopes that have integrated power measurement capabilities, and related methods and apparatus. More particularly, it describes determining the optical power of a fiber optic gyroscope (FOG) by temporarily adjusting the phase difference between two counter-propagating light beams, measuring the change in light intensity caused by the phase difference adjustment, and using the measured change in light intensity along with known characteristics of the FOG to compute an optical power value. The temporary adjustment in phase difference is preferably done in such a manner not to disturb the normal operation of the FOG.
Claims16
An interferometer fiber optic gyroscope (IFOG) that measures the intensity of an interference signal that is a combination of a first light signal and a second light signal out of phase with the first light signal, the IFOG comprising:
- a set of one or more controllers that computes a difference between a first measured intensity of the interference signal and a second measured intensity of the interference signal;
- wherein
- the first measured intensity results from a first phase difference between the first light signal and the second light signal at a first time;
- the second measured intensity results from a second phase difference between the first light signal and the second light signal at a second time;
- and
- the absolute value of the first phase difference differs from the absolute value of the second phase difference.
An interferometer fiber optic gyroscope (IFOG) that utilizes temporary changes to a phase difference between counter-propagating light beams to determine optical power.
A method of obtaining an optical power value for an interferometer fiber optic gyroscope (IFOG) comprising:
- determining an amount of change in light intensity caused by a change in phase difference between two counter-propagating light beams;
- and
- using the determined amount of change in light intensity to compute an optical power value.
Dependencies are inferred from the claim text.