Abstract: A method for manufacturing optical fiber with enhanced photosensitivity comprising the step of: forming a molten layer of glass and drawing a fiber from the molten layer of glass at a temperature of between about 1900° C. and 1995° C. Draw tension can be adjusted to attain the desired draw speed.

Abstract: An apparatus for compensating for chromatic dispersion over a wavelength band includes a dispersion compensating optical fiber that is coupled to an optical grating, which compensates for residual dispersion in the optical signal.

Abstract: A long-period fiber grating includes a fiber having a core surrounded by a cladding, and a plurality of refractive index variations periodically spaced along the longitudinal axis of a portion of the core of the fiber. The fiber is twisted throughout at least a portion of its length that includes the plurality of refractive index variations. By twisting the long-period fiber grating, polarization dependent loss is reduced by as much as 30 percent. Also, the peak wavelength of the light propagating through the long-period fiber grating that is coupled into the cladding of the fiber may be adjusted. The peak wavelength may be adjusted in as little as 0.1 nm increments by twisting the long-period fiber grating after the grating has been written and annealed.

Abstract: A dynamically tunable filter controls the magnitude of couplings between core and cladding modes of a waveguide by surrounding the waveguide with an overcladding having an adjustable refractive index. The coupled modes are attenuated along the core to produce the desired spectral response. The adjustment to the overcladding index is made in a range that is above the refractive index of the underlying cladding to vary amplitudes of attenuated bands of wavelengths without shifting central wavelengths of the bands.

Abstract: The present invention is a chromatic dispersion compensator. The chromatic dispersion compensator includes a first 3-port optical circulator, a first grating coupled to the second optical port of the first 3-port optical circulator. A polarization controller is coupled to the third optical port of the first 3-port optical circulator. The chromatic dispersion compensator further includes a second 3-port optical circulator, the polarization controller is coupled to the first optical port of the second 3-port optical circulator and a second grating is coupled to the second optical port of the second 3-port optical circulator.

Abstract: A method for manufacturing optical fiber with enhanced photosensitivity comprising the step of: forming a molten layer of glass and drawing a fiber from the molten layer of glass at a temperature of between about 1900° C. and 1995° C. Draw tension can be adjusted to attain the desired draw speed.

Abstract: The present relates to a method of changing the index of refraction of a optical fiber waveguide having a photosensitive core region fiber. The method includes providing a laser beam having a wavelength that will interact with the photosensitive core to change the index of refraction of the photosensitive core. The method uses a shadow mask and a lens. The lens is positioned to direct the portion of the laser beam passing through and the opening in the shadow mask onto the photosensitive core region of the optical waveguide fiber.

Abstract: The present invention is a chromatic dispersion compensator. The chromatic dispersion compensator includes a first 3-port optical circulator, a first grating coupled to the second optical port of the first 3-port optical circulator. A polarization controller is coupled to the third optical port of the first 3-port optical circulator. The chromatic dispersion compensator further includes a second 3-port optical circulator, the polarization controller is coupled to the first optical port of the second 3-port optical circulator and a second grating is coupled to the second optical port of the second 3-port optical circulator.

Abstract: Compound gain flattening filters of optical amplification include a series of filter components with spectral responses that are combined to approach a target loss spectrum. Small variations in the central wavelengths of the component responses can produce large errors in the combined response of the compound gain flattening filter. However, the components can be divided into sub-components with balanced central wavelength deviations to achieve the desired response goals despite exhibiting otherwise detrimental wavelength deviations.

Abstract: A dynamic slope compensation filter (DSCF) provides dynamic gain slope modification for an optical amplifier. The optical amplifier provides amplification for a plurality of wavelengths within an amplification band. The filter includes an optical waveguide core, an optical waveguide cladding and an optical waveguide overcladding. The optical waveguide core guides a plurality of wavelengths. The core has a core refractive index and includes at least one coupler that functions to couple at least a portion of the plurality of wavelengths from the core to the cladding. The optical waveguide cladding surrounds the core and has a cladding refractive index that is less than the core refractive index. The optical waveguide overcladding surrounds at least a portion of the cladding and has a variable overcladding refractive index that is adjustable within a range that is less than and greater than the cladding refractive index.

Abstract: Compound gain flattening filters of optical amplification include a series of filter components with spectral responses that are combined to approach a target loss spectrum. Small variations in the central wavelengths of the component responses can produce large errors in the combined response of the compound gain flattening filter. However, the components can be divided into sub-components with balanced central wavelength deviations to achieve the desired response goals despite exhibiting otherwise detrimental wavelength deviations.

Abstract: Packages for long period fiber gratings and other optical components (and methods for forming the packages) are described. According to an aspect of the invention, a hollow tube surrounding an optical fiber containing a long-period grating is collapsed in two areas, forming a seal at each end of the tube. According to another aspect of the invention, a hollow tube with a shelf section at each end surrounds an optical fiber containing a long-period grating. The hollow tube is sealed at each end with a fused frit. According to another aspect of the invention, a hollow tube surrounding an optical fiber containing a long-period grating is sealed at each end with a glass plug.

Abstract: Packages for long period fiber gratings and other optical components (and methods for forming the packages) are described. According to an aspect of the invention, a hollow tube surrounding an optical fiber containing a long-period grating is collapsed in two areas, forming a seal at each end of the tube. According to another aspect of the invention, a hollow tube with a shelf section at each end surrounds an optical fiber containing a long-period grating. The hollow tube is sealed at each end with a fused frit. According to another aspect of the invention, a hollow tube surrounding an optical fiber containing a long-period grating is sealed at each end with a glass plug.

Abstract: Packages for long period fiber gratings and other optical components (and methods for forming the packages) are described. According to an aspect of the invention, a hollow tube surrounding an optical fiber containing a long-period grating is collapsed in two areas, forming a seal at each end of the tube. According to another aspect of the invention, a hollow tube with a shelf section at each end surrounds an optical fiber containing a long-period grating. The hollow tube is sealed at each end with a fused frit. According to another aspect of the invention, a hollow tube surrounding an optical fiber containing a long-period grating is sealed at each end with a glass plug.

Abstract: Packages for long period fiber gratings and other optical components (and methods for forming the packages) are described. According to an aspect of the invention, a hollow tube surrounding an optical fiber containing a long-period grating is collapsed in two areas, forming a seal at each end of the tube. According to another aspect of the invention, a hollow tube with a shelf section at each end surrounds an optical fiber containing a long-period grating. The hollow tube is sealed at each end with a fused frit. According to another aspect of the invention, a hollow tube surrounding an optical fiber containing a long-period grating is sealed at each end with a glass plug.

Abstract: Packages for long period fiber gratings and other optical components (and methods for forming the packages) are described. According to an aspect of the invention, a hollow tube surrounding an optical fiber containing a long-period grating is collapsed in two areas, forming a seal at each end of the tube. According to another aspect of the invention, a hollow tube with a shelf section at each end surrounds an optical fiber containing a long-period grating. The hollow tube is sealed at each end with a fused frit. According to another aspect of the invention, a hollow tube surrounding an optical fiber containing a long-period grating is sealed at each end with a glass plug.

Abstract: Disclosed is a tuning method for optical interference devices which comprise at least one plurality of waveguides arranged to produce a preselected phase shift in light transmitted therethrough. The tuning is carried out by irradiating the plurality of waveguides using a source of UV light. The method is faster and more reproducible than other tuning methods known in the art, such as tuning by heat induced dopant diffusion. The method is exemplified by data taken using a Mach-Zehnder interferometer. However, the method is compatible with more sophisticated devices which use integrated waveguides or large numbers of waveguides in the phase changing portion of the device.

Abstract: The disclosed Mach-Zehnder (MZ)-type devices are planar waveguide devices, with interferometer arms of essentially equal length, with a maximum spacing between the arms (e.g., between the waveguide core centers) selected to make possible simultaneous exposure of both arms to refractive index-altering radiation. Exemplarily the maximum spacing is in the range 20-100 .mu.m. The simultaneous exposure of both waveguides makes it possible to form gratings of essential equal strength, such that typically no individual trimming is required. The resulting devices (typically add-drop filters) are substantially less sensitive to environmental changes (e.g., temperature gradients, mechanical vibrations) than prior art fiber-based devices, and are advantageously used in, for instance, WDM optical communication systems.

Abstract: A waveguide structure includes a substrate, a waveguide film, and an overlay material in contact with the waveguide film. The overlay material may also contact the substrate or the film may be disposed between the overlay and the substrate. The overlay material has a higher refractive index than the waveguide so that the ratio of the effective refractive indexes is substantially constant for all propagating modes supported by the waveguide.