Optical waveguides – Optical waveguide sensor
Patent
1996-08-01
1997-12-09
Ngo, John
Optical waveguides
Optical waveguide sensor
25022718, 324 97, 3242241, G02B 626
Patent
active
056968582
ABSTRACT:
A fiber optics sensor (10) and method for attaining accurate measurement are provided. A polarization maintaining optic fiber (22) forms a linear optical path. An optical element (24) is used to convert linearly polarized light waves to circularly polarized light waves which propagate along the optical path and pass through a sensing medium (24). Because of external stresses and disturbances, the optical element (24) introduces light of the wrong state of polarization into the optical path. The result is a scale factor error in the measurement and an extra incoherent D.C. light detected at the detector (36). The presence and magnitude of the extra incoherent D.C. light is used to provide a normalizing factor to compensate for the scale factor error.
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Ngo John
The Texas A&M University System
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