Stabilized fiber optic sensor

Optics: measuring and testing – By particle light scattering – With photocell detection

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

73657, 250227, 350 9615, 356346, 356352, G01B 902

Patent

active

045306036

ABSTRACT:
A fiber optic sensor comprises a length of optical fiber, forming a loop, and a fiber optic directional coupler for optically closing the loop. The loop and coupler form a resonant cavity for light circulating therethrough. A PZT cylinder, about which the fiber loop is wrapped, is utilized to control the total round trip phase delay of the circulating light, and thus, control the intensity of the optical output signal. The phase delay is adjusted to a point where the optical output signal is at maximum sensitivity to changes in phase. When the fiber loop is exposed to, e.g., acoustic waves, the loop length changes correspondingly, thereby causing the phase delay, and thus, the optical output signal to vary. By detecting variations in output signal intensity, the frequency and intensity of the acoustic waves may be determined. The sensor also includes a feedback system for stabilizing the fiber loop against low frequency thermal drift.

REFERENCES:
patent: 4002997 (1977-01-01), Thompson
patent: 4136929 (1979-01-01), Suzaki
patent: 4325636 (1982-04-01), Schiffner
patent: 4342499 (1982-08-01), Hicks, Jr.
patent: 4354760 (1982-10-01), Schiffner
patent: 4451151 (1984-05-01), Huignard
patent: 4469397 (1984-09-01), Shaw et al.
patent: 4473270 (1984-09-01), Shaw
Ezekiel, S.; Cole, J. A.; Harrison, J.; and Sanders, G.; "Passive Cavity Optical Rotation Sensor", SPIE, vol. 157, Laser Inertial Rotation Sensors, 1978, pp. 68-72.
Jackson, D. A.; Dandridge, A.; and Sheem, S. K., "Measurement of Small Phase Shifts Using a Single-Mode Optical-Fiber Interferometer", Optics Letters, vol. 5, No. 4, Apr., 1980, pp. 139-141.
Hill, K. O.; Kawasaki, B. S.; and Johnson, D. C., "cw Brillouin Laser", Applied Physics Letters, vol. 28, No. 10, May 15, 1976, pp. 608-609.
Bergh, et al., "Single-Mode Fibre Optic Directional Coupler", Electronics Letters, vol. 16, No. 7, Mar. 27, 1980.
Stokes et al., "All-Single-Mode Fiber Resonator", Optics Letters, vol. 7, No. 6, Jun. 1982.
Cielo, "Fiber Optic Hydrophone: Improved Strain Configuration and Environmental Noise Protection", Applied Optics, vol. 18, No. 17, pp. 2933-2937, 9/79.
Fritsh et al., "Simple Circuit for Feedback Stabilization of a Single-Mode Optical Fiber Interferometer", Rev. Sci. Instru., vol. 52, No. 7, pp. 996-1000, 7/81.
Ponikvar, Donald R. and Ezekiel, Shaoul, "Stabilized Single-Frequency Stimulated Brillouin Fiber Ring Laser", Optics Letters, vol. 6, No. 8, Aug., 1981, pp. 398-400.
Jackson, D. A.; Priest, R.; Dandridge, A.; and Tveten, A. B., "Elimination of Drift in a Single-Mode Optical Fiber Interferometer Using a Piezoelectrically Stretched Coiled Fiber", Applied Optics, vol. 19, No. 17, Sep. 1, 1980, pp. 2926-2929.
Sanders, G. A.; Prentiss, M. G.; and Ezekiel, S., "Passive Ring Resonator Method for Sensitive Inertial Rotation Measurements in Geophysics and Relativity", Optics Letters, vol. 6, No. 11, Nov., 1981, pp. 569.intg.571.
Petuchowski, S. J.; Giallorenzi, T. G.; and Sheem, S. K., "A Sensitive Fiber Optic Fabry-Perot Interferometer", IEEE Journal of Quantum Electronics, vol. QE-17, No. 11, Nov., 1981, pp. 2168-2170.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Stabilized fiber optic sensor does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Stabilized fiber optic sensor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Stabilized fiber optic sensor will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-632565

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.