Abstract: An optical fiber twisting apparatus that prevents line distortion in an optical fiber undergoing a drawing process and provides a consistent coating on a bare optical fiber. This optical fiber twisting apparatus includes a twist roller apparatus that having a twist roller that, by imparting a twist to an optical fiber, imparts a twist to a molten portion of an optical fiber preform positioned on an upstream side of the optical fiber, and a support portion that supports the twist roller. The accuracy of the outer circumference of the twist roller when the twist roller is forming a part of the twist roller apparatus is 15 ?m or less.

Abstract: The specification describes methods for the manufacture of very large optical fiber preforms wherein the core material is produced by MCVD. Previous limitations on preform size inherent in having the MCVD starting tube as part of the preform process are eliminated by removing the MCVD starting tube material from the collapsed MCVD rod by etching or mechanical grinding. Doped overcladding tubes are used to provide the outer segments of the refractive index profile thus making most effective use of the MCVD produced glass and allowing the production of significantly larger MCVD preforms than previously possible.

Abstract: An apparatus for adjusting the cooling members located beneath fiberizing bushings is disclosed having the capability of moving each cooling member, or one portion of each cooling member, in a generally vertical direction, and/or in a lateral and/or tilting direction. Also disclosed is a process of using the apparatus to make fibers from molten material including molten glass.

Abstract: Methods for modifying preform core ovality during and subsequent to the formation of an optical fiber preform. After MCVD deposition forms the core rod, but prior to overcladding of the core rod, the code rod may be etched to change its ovality. In order to etch the core rod, the core rod may be mounted to lathe, rotated by at least two rotors, and subjected to a heat source. Additionally, one of the at least two rotors may be phase-shifted from another one of the at least two rotors after the core rod is mounted on the lathe.

Abstract: A method of optical fiber manufacture involves the writing of a grating on the fiber using a laser. A first laser beam is directed on a first locality of the fiber having a circumference. A second laser beam is then directed on a second locality circumferentially displaced from the first locality. The first laser beam may be the second laser beam. In this way, a grating is formed on the fiber. The fiber may have a core and a cladding layer. The fiber may also comprise two gratings to form an interferometer.

Abstract: Bulk, superhard, B—C—N nanocomposite compacts were prepared by ball milling a mixture of graphite and hexagonal boron nitride, encapsulating the ball-milled mixture at a pressure in a range of from about 15 GPa to about 25 GPa, and sintering the pressurized encapsulated ball-milled mixture at a temperature in a range of from about 1800-2500 K. The product bulk, superhard, nanocomposite compacts were well sintered compacts with nanocrystalline grains of at least one high-pressure phase of B—C—N surrounded by amorphous diamond-like carbon grain boundaries. The bulk compacts had a measured Vicker's hardness in a range of from about 41 GPa to about 68 GPa.

Abstract: An effective process for removing organic coatings and binders from glass fiber surfaces in a manner that is both environmentally friendly and does not comprise the integrity or physical properties of the fiber.

Abstract: A method for manufacturing a preform for optical fibers by means of a vapor deposition process, wherein plasma conditions are created and wherein the plasma is moved back and forth along the longitudinal axis of the hollow substrate tube between a reversal point near the supply side and a reversal point near the discharge side of the hollow substrate tube, so that the location where the soot deposition associated with one phase takes place is axially spaced from the location where the soot deposition associated with the other phase(s) takes place.

Abstract: Microstructured optical fiber and method of making. Glass soot is deposited and then consolidated under conditions which are effective to trap a portion of the consolidation gases in the glass to thereby produce a non-periodic array of voids which may then be used to form a void containing cladding region in an optical fiber. Preferred void producing consolidation gases include nitrogen, argon, CO2, oxygen, chlorine, CF4, CO, SO2 and mixtures thereof.

Abstract: There is provided a method of manufacturing an optical waveguide, the method including: allowing a beam to be incident in an optical waveguide direction of an optical waveguide material; generating an optical soliton in the optical waveguide material by adjusting intensity of the incident beam according to the optical waveguide material; allowing the incident beam to be re-incident at an intensity higher than an intensity of the incident beam after checking generation of the optical soliton in the optical waveguide material; and increasing a refractive index of an optical soliton-generating area of the optical waveguide material by the re-incident beam to thereby form an optical waveguide.

Abstract: Optical fiber preforms can comprise a glass preform structure with an inner cavity. A powder can be placed within the inner cavity having an average primary particle size of less than about one micron. The powder can be in the form of an unagglomerated particles or a powder coating with a degree of agglomeration or hard fusing ranging from none to significant amounts as long as the primary particles are visible in a micrograph. Powders can be placed within a preform structure by forming a slurry with a dispersion of submicron/nanoscale particles within a cavity within the preform. In other embodiments, a powder coating is formed within a preform structure by depositing the powder coating directly from a reaction product stream. The formation of the powder coating can be formed within the reaction chamber or outside of the reaction chamber by flowing the product particle stream through a conduit leading to the preform structure. In additional embodiments, a powder coating is placed on an insert, e.g.

Abstract: A method of determining a heating amount adequate for fusion splicing is provided. In the method, the melting state of the end portions of optical fibers can be monitored on a real time basis so that fewer tests need to be performed. A method of fusion splicing and a fusion splicer are also provided. In the method of determining the heating amount, end portions of optical fibers that are placed opposite one another with a predetermined gap therebetween are heat-melted; an image of portions to be heat-melted is observed with an image-capturing device; and a luminance, a light emitting width, or a change in the luminance or the light emitting width is measured. In the method of fusion splicing, optical fibers are heat-melted with the heating amount that is determined using test fibers in advance, or determined using the optical fibers to be fusion spliced.

Abstract: There are the steps of conveying a glass plate by a roller conveyor including a plurality of rollers; and moving a roller in contact with the glass plate in conveyance to position the glass plate so as to conform a posture of the glass plate to a reference posture.

Abstract: To provide a elongating method for elongating an optical fiber parent material with high reliability by implementing a high precision control for the outer diameter in short time. This elongating method includes a process for switching a control method for at least one of the control items of measurement object, based on at least one of a difference between measured value and target value and a change rate of the difference per unit time, in measuring the outer diameter of a glass parent material elongating portion and making a feedback control for the elongating conditions based on the difference from the target outer diameter.

Abstract: A dehydration-sintering furnace for dehydrating and/or sintering an optical fiber preform for use in production of an optical fiber includes a muffle for accommodating the optical fiber preform, a heater for heating the muffle, and a pressure fluctuation absorbing apparatus connected to the muffle. Since the pressure fluctuation absorbing apparatus is thermally insulated from a room temperature atmosphere or heated, vapor produced in a dehydration-sintering process is prevented from condensing (liquefying) in a pressure fluctuation absorbing apparatus, thereby preventing reduced dehydration effectiveness in the muffle and reduced quality of the optical fiber preform.

Abstract: The present invention relates to an apparatus for carrying out a PCVD deposition process, wherein one or more doped or undoped layers are coated onto the interior of a glass substrate tube, which apparatus comprises an applicator having an inner and an outer wall and a microwave guide which opens into the applicator, which applicator extends around a cylindrical axis and which is provided with a passage adjacent to the inner wall, through which the microwaves can exit, over which cylindrical axis the substrate tube can be positioned, and wherein at least one choke of annular shape having a length l and a width w is centred around the cylindrical axis within the applicator.

Abstract: A method and apparatus for impulsively spinning optical fiber while the optical fiber is being drawn is disclosed herein.

Abstract: A process for making a non-zero dispersion shifted optical fiber having low splice loss and low attenuation and to an optical fiber produced by this process. A reduction of the splice loss is observed with decreasing drawing tension. The optical fiber has a core region that includes three segments and an inner cladding segment, each having a maximum refractive index percent difference, ?deltai %, i=0-3, the subscript i referring to a particular refractive index, the core segments being selected such that ?delta0%>?delta2%>?delta1%?0 and ?delta2%>?delta3%?0. Optical fibers exhibiting low splice loss were drawn at tensions not larger than 150 g, preferably not larger than 100 g.

Abstract: An optical fiber twisting apparatus that prevents line distortion in an optical fiber undergoing a drawing process and provides a consistent coating on a bare optical fiber. This optical fiber twisting apparatus includes a twist roller apparatus that having a twist roller that, by imparting a twist to an optical fiber, imparts a twist to a molten portion of an optical fiber preform positioned on an upstream side of the optical fiber, and a support portion that supports the twist roller. The accuracy of the outer circumference of the twist roller when the twist roller is forming a part of the twist roller apparatus is 15 ?m or less.

Abstract: In splicing two optical fibers to each other using an electric arc formed between electrodes images of the regions being heated and thereby fusioned to each other are taken. The images cover a rectangular field (43) having the fibers located centrally, along a center line of the field and parallel to the long sides of the field. The images are evaluated to determine a value of the position of the center of the electric arc in relation to the position of the end surfaces of the fibers. This value can then be used for placing the end surfaces just at the arc center. In the image the image of the optical fibers can be excluded so that only light intensity from the air discharge of the electric arc is recorded in the captured images. The field (41) excluded can be a narrow strip of uniform width located symmetrically around the image of the fibers.