Abstract: A technique is described for fabricating one or more optical devices in a carbon-coated optical fiber. A photosensitive optical fiber is provided having a hermetic carbon coating. Further provided is a laser having a beam output that is configured to inscribe one or more refractive index modulations into the optical fiber through the hermetic carbon layer while leaving the hermetic carbon layer intact. The laser is used to inscribe one or more optical devices into the optical fiber through the hermetic carbon layer.

Abstract: A technique is described for fabricating one or more optical devices in a carbon-coated optical fiber. A photosensitive optical fiber is provided having a hermetic carbon coating. Further provided is a laser having a beam output that is configured to inscribe one or more refractive index modulations into the optical fiber through the hermetic carbon layer while leaving the hermetic carbon layer intact. The laser is used to inscribe one or more optical devices into the optical fiber through the hermetic carbon layer.

Abstract: An optical fiber-based sensor is described that is suitable for operation in a gas-rich environment. The sensor comprises a chamber into which are mounted one or more segments of optical fiber, into which are inscribed a plurality of sensor gratings. Each of the plurality of sensor gratings is configured to have the same wavelength shift over time in response to a change in gas diffusion, such that gas diffusion parameters are excluded in the determination of the respective amount of change in temperature, applied strain, and gas diffusion. Also described is a fiber, and techniques for making same, comprising of cores extend through a common cladding. The cores are doped so as to create, in conjunction with the cladding, a plurality of waveguides having the same wavelength shift over time is response to a change in gas diffusion, but different wavelength shifts in response to changes in other parameters.

Abstract: A technique is described for fabricating one or more optical devices in a carbon-coated optical fiber. A photosensitive optical fiber is provided having a hermetic carbon coating. Further provided is a laser having a beam output that is configured to inscribe one or more refractive index modulations into the optical fiber through the hermetic carbon layer while leaving the hermetic carbon layer intact. The laser is used to inscribe one or more optical devices into the optical fiber through the hermetic carbon layer.

Abstract: A technique is described for fabricating one or more optical devices in a carbon-coated optical fiber. A photosensitive optical fiber is provided having a hermetic carbon coating. Further provided is a laser having a beam output that is configured to inscribe one or more refractive index modulations into the optical fiber through the hermetic carbon layer while leaving the hermetic carbon layer intact. The laser is used to inscribe one or more optical devices into the optical fiber through the hermetic carbon layer.

Abstract: An optical fiber-based sensor is described that is suitable for operation in a gas-rich environment. The sensor comprises a chamber into which are mounted one or more segments of optical fiber, into which are inscribed a plurality of sensor gratings. Each of the plurality of sensor gratings is configured to have the same wavelength shift over time in response to a change in gas diffusion, such that gas diffusion parameters are excluded in the determination of the respective amount of change in temperature, applied strain, and gas diffusion. Also described is a fiber, and techniques for making same, comprising of cores extend through a common cladding. The cores are doped so as to create, in conjunction with the cladding, a plurality of waveguides having the same wavelength shift over time is response to a change in gas diffusion, but different wavelength shifts in response to changes in other parameters.

Abstract: A technique is described for fabricating one or more optical devices in a carbon-coated optical fiber. A photosensitive optical fiber is provided having a hermetic carbon coating. Further provided is a laser having a beam output that is configured to inscribe one or more refractive index modulations into the optical fiber through the hermetic carbon layer while leaving the hermetic carbon layer intact. The laser is used to inscribe one or more optical devices into the optical fiber through the hermetic carbon layer.

Abstract: In a method and system for providing dispersion compensation in an optical system, there is coupled into the optical system at least one pathway into which there is connected a tunable chirped fiber Bragg grating, each such grating providing a respective tunable amount of dispersion. At least one respective DGD element is connected into the respective pathway for each such grating. The set of all such respective DGD elements in a given pathway introduces a bias differential group delay DGD(bias) having an absolute value that, for at least one tuning value of the grating, is substantially equal to differential group delay introduced by the grating.

Abstract: A twin core fiber for sensor applications is developed. It is particularly useful in de-coupling the strain and temperature and thus obtaining both measurement parameters at the same time and location. It is also particularly useful for measuring the temperature in a high humidity environment. The twin core fiber has two cores and each of the cores having a different dopant regime. Also, each of the cores includes a grating having substantially the same grating period.

Abstract: In a method and system for providing dispersion compensation in an optical system, there is coupled into the optical system at least one pathway into which there is connected a tunable chirped fiber Bragg grating, each such grating providing a respective tunable amount of dispersion. At least one respective DGD element is connected into the respective pathway for each such grating. The set of all such respective DGD elements in a given pathway introduces a bias differential group delay DGD(bias) having an absolute value that, for at least one tuning value of the grating, is substantially equal to differential group delay introduced by the grating.

Abstract: In a method and system for providing dispersion compensation in an optical system, there is coupled into the optical system at least one pathway into which there is connected a tunable chirped fiber Bragg grating, each such grating providing a respective tunable amount of dispersion. At least one respective DGD element is connected into the respective pathway for each such grating. The set of all such respective DGD elements in a given pathway introduces a bias differential group delay DGD(bias) having an absolute value that, for at least one tuning value of the grating, is substantially equal to differential group delay introduced by the grating.

Abstract: A twin core fiber for sensor applications is developed. It is particularly useful in de-coupling the strain and temperature and thus obtaining both measurement parameters at the same time and location. It is also particularly useful for measuring the temperature in a high humidity environment. The twin core fiber has two cores and each of the cores having a different dopant regime. Also, each of the cores includes a grating having substantially the same grating period.

Abstract: In a method and system for providing dispersion compensation in an optical system, there is coupled into the optical system at least one pathway into which there is connected a tunable chirped fiber Bragg grating, each such grating providing a respective tunable amount of dispersion. At least one respective DGD element is connected into the respective pathway for each such grating. The set of all such respective DGD elements in a given pathway introduces a bias differential group delay DGD(bias) having an absolute value that, for at least one tuning value of the grating, is substantially equal to differential group delay introduced by the grating.

Abstract: A temperature compensating device for optical fiber gratings includes first and second expansion members having different coefficients of thermal expansion. The expansion members are elongated in a direction parallel to the fiber grating and levers are secured to both ends of the expansion members. Each lever has a first end flexibly secured to a respective end of the first expansion member and a middle portion flexibly secured to a respective end of the second expansion member. The other end of each lever is secured to a respective end of the fiber grating. The expansion members, the levers and the fiber grating all lie substantially in a single plane. There is also disclosed a package for holding four of the temperature compensating devices in two rows of two devices each, with their fiber gratings adjacent each other so that when viewed in a plane orthogonally to the longitudinal axes of the fiber gratings, the fiber gratings are each at a respective corner of a rectangle.