Process for preparing an optical fiber sensor with enhanced sensitivity

Patent 6035082 Issued on March 7, 2000. Estimated Expiration Date:

March 16, 2018. 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.

Abstract Claims Description Full Text

Patent References

Single mode modified W-fiber
Patent #: 4691991
Issued on: 09/08/1987
Inventor: Unger

Optical waveguide sensor arrangement having guided modes-non guided modes grating coupler Patent #: 5641956
Issued on: 06/24/1997
Inventor: Vengsarkar, et al.

Inventors

Assignee

Luna Innovations, Inc.

Application

No. 039688 filed on 03/16/1998

US Classes:

385/37, Grating385/12OPTICAL WAVEGUIDE SENSOR

Examiners

Primary: Lee, John D.
Assistant: Kang, Ellen E.

Attorney, Agent or Firm

Bryant; Joy L.

International Class

G02B 006/34

Abstract

A process for preparing an optical fiber having at least one long period grating with enhanced sensitivity is provided. A length of optical fiber having a refractive index profile is provided. The optical fiber supports a core mode and cladding modes for a range of operational wavelengths. Group indices are identified for the core mode and the cladding modes for a specific wavelength wherein the group indices are equal to each other. A long period grating is written in the optical fiber. The long period grating has a grating defined by the group indices and it couples light from the core mode to a cladding mode proximate to where the group indices are equal. The optical fibers prepared by the present invention may be used for measuring an environmental perturbation where high sensitivity is required.

Other References

Byeong Ha Lee, Yu Lee, Sang Bae Lee, Sang Sam Choi, Joo Nyung Jang, "Displacements of the Resonant Peaks of a Long-Period Fiber Grating Induced by a Change of Ambient Refractive Index," Optics Letters, Jul. 23, 1997, pp. 1769-1771, vol. 22, No. 23, Optical Society of America, U.S.A
Ashish M. Vengsarkar, Paul J. Lemaire, Justing B. Judkins, Vikram Bhatia, Turan Erdogan, J.E. Sipe, "Long-Period Fiber Gratings as Band-Rejection Filters," Journal of Lightwave Technology, Jan. 1996, pp. 58-65, vol. 14, No. 1, IEEE, U.S.A
A.M. Vengsarkar, P.J. Lemaire, G. Jacobovitz-Veselka, J.B. Judkins, V. Bhatia, T. Erdogan, J.E. Sipe, "Long-Period Cladding-Mode-Coupled Fiber Gratings: Properties and Applications," 1995 Technical Digest Series, Sep. 9-11, 1995, pp. SaB2-1-SaB2-4, vol. 22, Optical Society of America, Portland, Oregon
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Zheng Zhang, James S. Sirkis, "Temperature-Compensated Long Period Grating Chemical Sensor," Technical Digest Series, Oct. 28-31, 1997, pp. 294-297, vol. 16, Optical Society of America, U.S.A
H.Y. Tam, W.Du, "Simple Method for Enhancing Fiber Grating's Bragg Wavelength Shift," SPIE, Oct. 11, 1996, pp. 300-304, vol. 289