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.
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.
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