Fiber tip based sensor system for measurements of pressure gradient, air particle velocity and acoustic intensity
Patent 7224465 Issued on May 29, 2007. Estimated Expiration Date: January 21, 2025. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
356/480, Resonant cavity356/519, Having partially reflecting plates in series (e.g., Fabry-Perot type)385/12, OPTICAL WAVEGUIDE SENSOR73/705Photoelectric
A fiber optic sensor system for pressure measurements where the design permits multiplexity on the input side of the system and the optical part of the system, which has a sensor Fabry-Perot interferometer and a read-out interferometer, is based on low coherence fiber-optic interferometry techniques. This permits a high dynamic range and low sensitivity to the wavelength fluctuation of the light source as well as to the optical intensity fluctuations. The system includes fiber tip based Fabry-Perot sensors, where each sensor includes a diaphragm as the transducer. A combined pressure gradient sensor, air particle velocity sensor, as well as acoustic intensity sensor is built based on the fiber tip based Fabry-Perot sensors.
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