Abstract: Techniques and systems suitable for performing low-loss fusion splicing of optical waveguide sections are provided. According to some embodiments, multiple laser beams (from one or more laser) may be utilized to uniformly heat a splice region including portions of the optical waveguide sections to be spliced, which may have different cross-sectional dimensions. According to some embodiments, the relative distance of the optical waveguide sections and/or the power of the multiple laser beams may be varied during splicing operations.

Abstract: Techniques and systems suitable for performing low-loss fusion splicing of optical waveguide sections are provided. According to some embodiments, multiple laser beams (from one or more laser) may be utilized to uniformly heat a splice region including portions of the optical waveguide sections to be spliced, which may have different cross-sectional dimensions. According to some embodiments, the relative distance of the optical waveguide sections and/or the power of the multiple laser beams may be varied during splicing operations.

Abstract: Techniques and systems suitable for performing low-loss fusion splicing of optical waveguide sections are provided. According to some embodiments, multiple laser beams (from one or more laser) may be utilized to uniformly heat a splice region including portions of the optical waveguide sections to be spliced, which may have different cross-sectional dimensions. According to some embodiments, the relative distance of the optical waveguide sections and/or the power of the multiple laser beams may be varied during splicing operations.

Abstract: Methods and apparatus provide for birefringent waveguides suitable for optical systems exhibiting polarization dependence such as interferometer sensors including Sagnac interferometric fiber optic gyroscopes (IFOG). The waveguides, for some embodiments, may offer single polarization performance over lengths of about a kilometer or more due to polarization dependent attenuation. According to some embodiments, the waveguides incorporate a pure silica core for resistance to radiation-induced attenuation (RIA).

Abstract: Methods and apparatus provide for birefringent waveguides suitable for optical systems exhibiting polarization dependence such as interferometer sensors including Sagnac interferometric fiber optic gyroscopes (IFOG). The waveguides, for some embodiments, may offer single polarization performance over lengths of about a kilometer or more due to polarization dependent attenuation. According to some embodiments, the waveguides incorporate a pure silica core for resistance to radiation-induced attenuation (RIA).

Abstract: Methods and apparatus provide for birefringent waveguides suitable for optical systems exhibiting polarization dependence such as interferometer sensors including Sagnac interferometric fiber optic gyroscopes (IFOG). The waveguides, for some embodiments, may offer single polarization performance over lengths of about a kilometer or more due to polarization dependent attenuation. According to some embodiments, the waveguides incorporate a pure silica core for resistance to radiation-induced attenuation (RIA).

Abstract: Methods and apparatus provide for birefringent waveguides suitable for optical systems exhibiting polarization dependence such as interferometer sensors including Sagnac interferometric fiber optic gyroscopes (IFOG). The waveguides, for some embodiments, may offer single polarization performance over lengths of about a kilometer or more due to polarization dependent attenuation. According to some embodiments, the waveguides incorporate a pure silica core for resistance to radiation-induced attenuation (RIA).

Abstract: The present invention provides a new and unique method for increasing the photosensitivity of a large diameter optical waveguide having a cross-section of at least about 0.3 millimeters. The method features loading the large diameter optical waveguide with a photosensitizing gas at a pressure at least about 4000 pounds per square inch (PSI) at a temperature of at least about 250° Celsius. The photosensitizing gas may be hydrogen, Deuterium or other suitable gas. The method also includes the step of using a particular large diameter optical waveguide having a core more than 1000 microns from the surface thereof. The method may be used as part of a process for writing a Bragg grating in an inner core or a cladding of the large diameter optical waveguide.

Abstract: The present invention provides a new and unique method for increasing the photosensitivity of a large diameter optical waveguide having a cross-section of at least about 0.3 millimeters. The method features loading the large diameter optical waveguide with a photosensitizing gas at a pressure at least about 4000 pounds per square inch (PSI) at a temperature of at least about 250E Celsius. The photosensitizing gas may be hydrogen, Deuterium or other suitable gas. The method also includes the step of using a particular large diameter optical waveguide having a diameter of greater than 0.9 millimeters. The method may be used as part of a process for writing a Bragg grating in an inner core or a cladding of the large diameter optical waveguide.

Abstract: A tunable optical filter has a large diameter cane waveguide with “side-holes” in the cane cross-section that reduce the force required to compress the large diameter optical waveguide without overly compromising the buckling strength thereof. The large diameter optical waveguide has a cross-section of at least about 0.3 millimeters, including at least one inner core, a Bragg grating arranged therein, a cladding surrounding the inner core, and a structural configuration for providing a reduced bulk modulus of compressibility and maintaining the anti-buckling strength of the large diameter optical waveguide. The structural configuration reduces the cross-sectional area of the large diameter optical waveguide. These side holes reduce the amount of glass that needs to be compressed, but retains the large diameter.

Abstract: A fluid diffusion resistant tube-encased fiber grating pressure sensor includes an optical fiber 10 having a Bragg grating 12 impressed therein which is encased within a sensing element, such as a glass capillary shell 20. A fluid blocking coating 30 is disposed on the outside surface of the capillary shell to prevent the diffusion of fluids, such as water molecules from diffusing into the shell. The fluid diffusion resistant fiber optic sensor reduces errors caused by the diffusion of water into the shell when the sensor is exposed to harsh conditions.

Abstract: A method is provided for precise and repeatable location of one or more Bragg gratings in a large diameter optical waveguide having a cross-section of at least about 0.3 millimeters, featuring the steps of: defining a reference location on a fixed placement datum arranged on a waveguide fixture device; defining one or more desired locations on a large diameter optical waveguide arranged on the waveguide fixture location in relation to the reference location; and writing one or more Bragg gratings in the large diameter optical waveguide at the one or more desired locations based on the reference location on the fixed placement datum. The step of defining the reference location may include marking the fixed placement datum with a scribe mark thereon; and securing the fixed placement datum in a groove in a waveguide fixture device.

Abstract: A fluid diffusion resistant tube-encased fiber grating pressure sensor includes an optical fiber 10 having a Bragg grating 12 impressed therein which is encased within a sensing element, such as a glass capillary shell 20. A fluid blocking coating 30 is disposed on the outside surface of the capillary shell to prevent the diffusion of fluids, such as water molecules from diffusing into the shell. The fluid diffusion resistant fiber optic sensor reduces errors caused by the diffusion of water into the shell when the sensor is exposed to harsh conditions.

Abstract: Techniques and systems suitable for performing low-loss fusion splicing of optical waveguide sections are provided. According to some embodiments, multiple laser beams (from one or more laser) may be utilized to uniformly heat a splice region including portions of the optical waveguide sections to be spliced, which may have different cross-sectional dimensions. According to some embodiments, the relative distance of the optical waveguide sections and/or the power of the multiple laser beams may be varied during splicing operations.

Abstract: A method is provided for precise and repeatable location of one or more Bragg gratings in a large diameter optical waveguide having a cross-section of at least about 0.3 millimeters, featuring the steps of: defining a reference location on a fixed placement datum arranged on a waveguide fixture device; defining one or more desired locations on a large diameter optical waveguide arranged on the waveguide fixture location in relation to the reference location; and writing one or more Bragg gratings in the large diameter optical waveguide at the one or more desired locations based on the reference location on the fixed placement datum. The step of defining the reference location may include marking the fixed placement datum with a scribe mark thereon; and securing the fixed placement datum in a groove in a waveguide fixture device.

Abstract: A fluid diffusion resistant tube-encased fiber grating pressure sensor includes an optical fiber 10 having a Bragg grating 12 impressed therein which is encased within a sensing element, such as a glass capillary shell 20. A fluid blocking coating 30 is disposed on the outside surface of the capillary shell to prevent the diffusion of fluids, such as water molecules from diffusing into the shell. The fluid diffusion resistant fiber optic sensor reduces errors caused by the diffusion of water into the shell when the sensor is exposed to harsh conditions.

Abstract: A tunable optical filter has a large diameter cane waveguide with “side-holes” in the cane cross-section that reduce the force required to compress the large diameter optical waveguide without overly compromising the buckling strength thereof. The large diameter optical waveguide has a cross-section of at least about 0.3 millimeters, including at least one inner core, a Bragg grating arranged therein, a cladding surrounding the inner core, and a structural configuration for providing a reduced bulk modulus of compressibility and maintaining the anti-buckling strength of the large diameter optical waveguide. The structural configuration reduces the cross-sectional area of the large diameter optical waveguide. These side holes reduce the amount of glass that needs to be compressed, but retains the large diameter.

Abstract: The present invention provides a new and unique method for increasing the photosensitivity of a large diameter optical waveguide having a cross-section of at least about 0.3 millimeters. The method features loading the large diameter optical waveguide with a photosensitizing gas at a pressure at least about 4000 pounds per square inch (PSI) at a temperature of at least about 250E Celsius. The photosensitizing gas may be hydrogen, Deuterium or other suitable gas. The method also includes the step of using a particular large diameter optical waveguide having a diameter of greater than 0.9 millimeters. The method may be used as part of a process for writing a Bragg grating in an inner core or a cladding of the large diameter optical waveguide.

Abstract: A large diameter waveguide is provided having a diameter of at least about 0.3 millimeters, and an outer cladding with an inner core with a long period grating included therein. The long period grating either couples forward propagating cores modes to forward propagating cladding modes of one optical signal travelling in one direction in the large diameter waveguide, or couples forward propagating cladding modes to forward propagating cores modes of another optical signal travelling in another direction in the large diameter waveguide. The long period grating has an optical parameter that changes in response to an application of a compressive force on the optical waveguide. The outer cladding may also have the long period grating written therein. The long period grating has concatenated periodic or aperiodic gratings. The optical waveguide may be shaped like a dogbone structure having wider outer sections and a narrower central section inbetween.

Abstract: A compression-tuned fiber Bragg grating based reconfigurable wavelength add/drop module has a compression force assembly and an all-glass Bragg grating compression unit having gratings spaced along an axis of compression. The compression force assembly responds to a control electronics signal containing information about a selected wavelength of a channel to be added to or dropped from an optical traffic signal, for providing a compression force applied along the axis of compression. The compression unit responds to the optical traffic signal and the compression force, for providing an all-glass Bragg grating compression unit optical signal having the selected wavelength of the channel to be added to or dropped from the optical traffic signal. The compression unit optical signal may include either the traffic with an added reflected channel(s), or a dropped reflected channel(s).