Abstract: Disclosed is a dispersion controlled optical waveguide fiber, and telecommunication systems using such a waveguide fiber, in which the end to end total dispersion and total dispersion slope is controlled by varying the refractive index profile along the fiber length. The waveguide fiber includes length portions each of which is characterized by total dispersion having a magnitude and sign and total dispersion slope having a magnitude and sign. The magnitudes and signs of total dispersion and total dispersion slope of respective length portions are chosen to provide for the optical waveguide fiber a desired end to end total dispersion and total dispersion slope. An advantage is achieved in the present invention by designing the refractive index profiles of the length portions to have total dispersion and total dispersion slope of opposite sign.

Abstract: A Dispersion Compensation (DC) fiber and transmission line including the same. The DC fiber has a refractive index profile having a central core with a core delta (&Dgr;1) value greater than 1.5%, a moat surrounding the central core having a moat delta (&Dgr;2) value less negative than −0.65%, and a ring surrounding the moat having a positive ring delta (&Dgr;3). The DC fiber's refractive index profile is selected to provide total dispersion less than −87 and greater than −167 ps/nm/km; dispersion slope more negative than −0.30 ps/nm2/km; and kappa of greater than 151 and less than 244 nm, all at 1550 nm. The DC fiber, when used in transmission lines, may provide low average residual dispersions across the C, L, C+L and S bands when such lines include transmission fibers with total dispersion between 4 and 10 ps/nm/km, and a positive dispersion slopes of less than 0.045 ps/nm2/km at 1550 nm. Further embodiments are described that include Raman pumping.

Abstract: A dispersion and dispersion slope compensating optical fiber includes a segmented core and a cladding layer wherein the refractive index profile is selected to provide a dispersion having a maximum deviation of less than 7 ps/nm-km over a wavelength band from 1550 nm to 1610 nm. According to a further embodiment of the invention, a dispersion compensating optical fiber is provided having a refractive index profile with a central core segment having a positive relative refractive index; a depressed moat segment on a periphery of the central core segment having a relative refractive index that is more negative than −1.2%; and an annular ring segment outward from the depressed moat segment having a relative refractive index that is greater than 1.2%.

Abstract: A method for doping silica soot with fluorine during laydown, including providing a bait rod, and providing a burner, wherein the burner emits a reactant flame. The method also including providing at least one first gas-feed separate from the burner, wherein the gas-feed supplies a first jet of fluorine-based gases, and depositing a layer of silica soot on the bait rod by vaporizing a silica producing gas within the reactant flame of the burner. The method further including supplying the first jet of fluorine-based gases to the silica soot deposited on to the bait rod via the first gas-feed subsequent to vaporizing at least a portion of the silica producing gas within the reactant flame of the burner.

Abstract: A burner module for delivering a flow of chemical reactants to a combustion site of a chemical vapor deposition process includes a plurality of substantially planar layers. The substantially planar layers are arranged in a generally parallel and fixed relationship and define an inlet, an outlet and a passage fluidly connecting the inlet and outlet. At least one of the layers is a distribution layer having a plurality of apertures therethrough and fluidly communicating with the passage. The plurality of apertures collectively define a non-uniform pattern arranged and configured to improve the uniformity of a flow out through the outlet. Burner adapter and assembly embodiments are also included.

Abstract: A method for making silica includes delivering a silica precursor comprising a pseudohalogen to a conversion site and passing the silica precursor through a flame to produce silica soot.

Abstract: A method of manufacturing a silica-containing article used in the manufacture of an optical fiber includes the steps of applying to the silica-containing article a protective layer, and then transporting the coated article to a second factory for further processing. The layer facilitates ease of removal of particulates that deposit on the protective layer. The layer preferably ablates during, or can be readily removed subsequent to, further processing of the silica-containing article. Any intermediate product used in the manufacture of an optical fiber, for example, a core blank, core cane segment, consolidated preform, etc. may be readily shipped between various factories because the articles are protected against break-inducing particulates by the protective layer.

Abstract: Disclosed is a dispersion compensating optical fiber that includes a refractive index profile selected to provide dispersion at 1550 nm of between −90 and −150 ps/nm/km; dispersion slope at 1550 nm of less than −1.5 ps/nm2/km; and kappa of between 40 and 95. The profile preferably has a core surrounded by a cladding layer of refractive index &Dgr;c, and at least three radially adjacent regions including a central core region having &Dgr;1, a moat region having a refractive index &Dgr;2, and an annular ring region having a refractive index &Dgr;3, wherein &Dgr;1>&Dgr;3>&Dgr;c>&Dgr;2.

Abstract: An optical signal transmission link includes a first single mode optical fiber for receiving an optical signal, and a graded index multimode optical fiber for receiving the optical signal from the first single mode optical fiber. The multimode fiber of the transmission link is adapted to support the propagation of greater than or equal to 4 LP modes within the wavelength range of from about 1310 nm to about 1550 nm, has a mode field diameter of the fundamental mode of within the range of from about 3.0 &mgr;m to about 14.0 &mgr;m within the wavelength range of from about 1300 nm to about 1650 nm, and has a numerical aperture (NA) value of greater than or equal to about 0.16.

Abstract: The present invention relates to a dispersion compensating optical fiber (“DC fiber”) having a segmented core and having a negative total dispersion and negative dispersion slope in the C-band. The index profile of the fiber is selected to provide an optical properties suitable for a high performance communication system operating in the C-band wavelength band, i.e., between about 1525 nm to 1565 nm. The DC fiber according to the invention exhibits dispersion slope at 1549 nm more negative than −3.4 ps/nM2-km and has a negative &Dgr;2% that is more negative than −0.4%. Preferably, the DC fiber has a total dispersion more negative than −125 ps/nm2-km. The DC fiber may be optically connected to a Non-Zero Dispersion Shifted Fiber (NZDSF) in the system to compensate for dispersion thereof. Optionally, the transmission system may include a positive dispersion, positive slope trim fiber.

Abstract: Disclosed is a dispersion compensating and dispersion slope compensating single mode optical waveguide fiber. The refractive index profiles of waveguide fibers in accord with the invention are disclosed and described. These index profiles provide a waveguide fiber having negative total dispersion and negative total dispersion slope so that a standard waveguide fiber is compensated over an extended wavelength range. A telecommunications link using the fiber in accord with the invention is also disclosed and described. A standard fiber to compensating fiber length ratio in the range of 1:1 to 3:1 is shown to give optimum link performance with respect to limiting non-linear dispersion effects.

Abstract: Disclosed are refractive index profiles for total dispersion compensating optical waveguide fibers for use in high data rate, long length telecommunications systems. The optical waveguide fibers in accord with the invention provide substantially equal compensation of total dispersion over a range of wavelengths, thus facilitating wavelength division multiplexed systems. Also disclosed are spans of optical waveguide fiber that include a length of transmission fiber together with a length of the compensating fiber. The spans are joined end to end in series arrangement to form the optical waveguide fiber part of a telecommunication system.

Abstract: A dispersion compensating (DC) fiber preferably including a central segment having a relative refractive index, a depressed moat segment, an intermediate segment, an annular ring segment and a cladding layer. The relative refractive index profile of the DC fiber is selected to provide negative dispersion, negative dispersion slope, a &kgr; value of less than or equal to about 100, and MPI of less than −40 dB at 1550 nm. The DC fiber preferably has a pin array bend loss of less than or equal to about 30 dB at a wavelength of about 1550 nm.

Abstract: A single mode dispersion and dispersion slope compensating optical fiber includes a central core segment, a depressed moat segment, an annular ring segment, and a cladding layer. Each of the segments of the fiber have a relative refractive index that are selected to provide negative dispersion at a wavelength of within the range of about 1530 nm to about 1620 nm, negative dispersion slope at a wavelength of within the range of about 1530 nm to about 1620 nm, a kappa value of within the range of 40 to about 60 at a wavelength of about 1550 nm, and a fiber cut-off wavelength of less than about 1650 nm, and more preferably less than 1550 nm.

Abstract: A dispersion compensating module, mode converter, coupler and dispersion compensated optical fiber therein. The dispersion compensating fiber has a plurality of core segments, the refractive index profile being selected to exhibit properties such that an LP02 mode at 1550 nm may be propagated a distance (generally 0.5-3.0 km), upon conversion to LP02, to compensate for dispersion of a length of transmission waveguide preferably greater than 25 km propagating in an LP01 mode. In another embodiment, the dispersion compensating module has a mode converter having a reflective fiber grating for converting a first to a second mode interconnected to a dispersion compensated fiber propagating in the second mode. The mode converter has a coupler adapted to operatively couple light propagating in a first mode from a first fiber into a second, and a reflective fiber grating operatively coupled to the second fiber; the grating being capable of converting light from the first into the second mode.

Abstract: Dispersion managed fibers which preferably have a central core region, a moat region, and a ring region are provided. The central core region preferably has an alpha profile with an alpha value preferably less than about 2.3. The moat region preferably includes four sub-regions, namely, a first sub-region (11) in which the index of refraction decreases, a second sub-region (12) in which the index of refraction increases substantially linearly, a fourth sub-region (14) in which the index of refraction again increases substantially linearly, and a third sub-region (13) which serves as a transition region which smoothly connects the third and fourth substantially linear sub-regions.

Abstract: A method for manufacturing optical fiber preform and fiber. According to the method, a core cane segment is formed with a refractive index delta preferably between 0.2% and 3% that is most preferably formed by an OVD method. A sleeve is formed including at least one down-doped moat preferably having a refractive index delta between −0.1% and −1.2% and at least one up-doped ring preferably having a refractive index delta between 0.1% and 1.2%. The sleeve is formed by introducing glass precursor and dopant compounds into a cavity of a preferably silica glass tube (e.g., one of an MCVD and PCVD method). The core cane segment is inserted into the sleeve and the sleeve is collapsed onto the core cane segment to form a core-sleeve assembly. The core-sleeve assembly is again drawn into a cane and additional cladding is preferably formed thereon. Optical fiber may be drawn from the preform in a conventional draw apparatus.

Abstract: Optical fiber is provided with a periodically reversing spin while the fiber is pulled through a melt zone. A cooled region of the fiber downstream from the melt zone passes between a pair of opposed elements. The opposed elements are moved so that surface regions engaging the fiber move in opposite lateral directions relative to one another, thus spinning the fiber about its axis. The lateral movement of the engaged surface portions is periodically reversed to reverse the spin direction. The opposed elements may include belts or rollers, which can be tilted to orientations oblique to the longitudinal direction of the fiber.

Abstract: A fiber (106) having low polarization mode dispersion is made by heating the end of a preform (100) with a furnace (101). The fiber is drawn from the heated end. The fiber passes between two rollers (102, 104). As the fiber passes therebetween, the angular tilt of each of the rollers is changed so that a spin is imparted to the fiber.

Abstract: Disclosed is a dispersion compensating optical fiber that includes a core surrounded by a cladding layer of refractive index &Dgr;c. The core includes at least three radially adjacent regions, a central core region having &Dgr;1, a moat region having a refractive index &Dgr;2 and an annular ring region having a refractive index &Dgr;3, such that &Dgr;1>&Dgr;3>&Dgr;c>&Dgr;2. The fiber exhibits a dispersion at 1550 which is less than −30 ps/nm/km, and a &kgr; value obtained by dividing the dispersion value by the dispersion slope which is between 40 and 100.