Abstract: A heating apparatus of an induction furnace used for stretching large-diameter preformed rods of optical fibers, said heating apparatus of the induction furnace comprising a furnace casing, a graphite exothermic sleeve, an insulating layer and an induction coil. At the upper end of the graphite exothermic sleeve is provided a floating seal gland, the inner bore thereof being adapted to the upper end of the graphite exothermic sleeve, and the outer periphery of the floating seal gland being adapted to the top cover plate furnace hole of the furnace casing. The use of the floating seal gland increases furnace stability and prolongs furnace life.

Abstract: Apparatus for applying traction to an elongate cylindrical element produced by fusion of an end portion of a preform of glass material, in which a traction device is capable of being connected to a portion of the elongate cylindrical element to provide traction of the elongate cylindrical element along an axis. A device for the rotation of the elongate cylindrical element applies a twist to the elongate cylindrical element about the axis simultaneously with the traction.

Abstract: Apparatus, system and methods of using the apparatus and system to manipulate fiber(s) into a chopper, winder or other fiber(s) processing equipment. By using the apparatus the operator(s) are freed up for pressing duties that will increase productivity and also create a safer workplace. The apparatus supports and constrains slowly or rapidly running fiber(s) and moves through a sequence of movements that reposition the fiber(s) into a path that places the running fiber(s) in the proper location for processing in the chopper, winder or other processing equipment and also places the running fiber(s) into a desired groove or valley on a separator roll or guide.

Abstract: A method of processing an optical fiber includes introducing fiber that has passed a pulling mechanism to a shredding unit with an introducing unit. The introducing unit includes a movable unit including a notch configured to fit with a capstan roller included in the pulling mechanism, a sliding mechanism that attaches the movable unit slidably with respect to a main body of the introducing unit, and a restoring mechanism configured to restore the movable unit to an initial position when the movable unit has slid. The method includes shredding the fiber introduced by the introducing unit into fiber pieces, and suctioning, carrying, and collecting the fiber pieces. A method of drawing an optical fiber includes drawing the fiber while controlling a drawing speed, adjusting a diameter of the fiber to a diameter passable through a die, and arranging the die around the fiber having the diameter passable through the die.

Abstract: Processes and systems for producing glass fibers having regions devoid of glass using submerged combustion melters, including feeding a vitrifiable feed material into a feed inlet of a melting zone of a melter vessel, and heating the vitrifiable material with at least one burner directing combustion products of an oxidant and a first fuel into the melting zone under a level of the molten material in the zone. One or more of the burners is configured to impart heat and turbulence to the molten material, producing a turbulent molten material comprising a plurality of bubbles suspended in the molten material, the bubbles comprising at least some of the combustion products, and optionally other gas species introduced by the burners. The molten material and bubbles are drawn through a bushing fluidly connected to a forehearth to produce a glass fiber comprising a plurality of interior regions substantially devoid of glass.

Abstract: An optical fiber production system and method are provided for producing optical fiber. An optical fiber is drawn from a preform in a furnace and passes through a treatment device under a reduced pressure in the range of 0.01 to 0.80 atm. The treatment device cools the bare optical fiber as it cools to a temperature in the range of at least 1,600° C. to 1,300° C. A non-contact fiber centering device is located near an exit of the treatment device to provide centering of the optical fiber as it exits the treatment device.

Abstract: Methods for producing a coated optical fiber may include drawing an optical fiber from a draw furnace along a first pathway and redirecting the optical fiber along a second, different pathway which is non-parallel with the first pathway. The optical fiber may be coated as it travels along the second pathway.

Abstract: An apparatus includes: an introducer to introduce a glass optical fiber that has passed a pulling mechanism pulling, to draw the glass optical fiber, one end of an optical fiber preform that has been fused by heating; a shredder including a casing connected to the introducer and a shredding mechanism to shred the glass optical fiber introduced by the introducer in the casing into glass optical-fiber pieces; a pipe connected to the casing of the shredder and to carry the glass optical-fiber pieces; and a suction unit connected to the pipe and to suction the glass optical-fiber pieces via the pipe.

Abstract: A method of manufacturing an optical fiber includes providing a preform in a furnace, and drawing a plurality of optical fibers from the preform at a plurality of different draw tensions. A bandwidth characteristic of each of the optical fiber is drawn at the different draw tensions is measured. A draw tension setpoint is selected based on the measured bandwidth characteristic of each optical fiber and the draw tension is adjusted to the selected draw tension setpoint. The method further includes drawing from the preform a tuned optical fiber at the selected draw tension setpoint which provides peak bandwidth.

Abstract: To provide a method for the inexpensive manufacture of a deposition burner with small manufacturing tolerances for use in the synthesis of quartz glass, and wherein moreover, when the deposition burner is used as intended, the risk of contamination of the quartz glass to be produced is low, the invention suggests the following method steps: (a) providing a start cylinder of quartz glass (40) which is mechanically provided with longitudinal bores (46, 47); (b) elongating the start cylinder with formation of a burner strand (42), the longitudinal bores being shaped as elongated channels extending in parallel with one another; (c) cutting the burner strand into pieces in the form of cylindrical quartz glass blocks (43), each being provided with passage lines extending in parallel with a central axis of the quartz glass block; and (d) manufacturing the deposition burner by using a respective one of such quartz glass blocks as burner head which has a proximal end and a distal end, the passage lines serving the sup

Abstract: Drawing methods and drawing furnaces for drawing an optical fiber with small non-circularity by simple drawing system are provided. An optical fiber preform is received into a muffle tube and heated by a primary heater placed to surround the muffle tube. The optical fiber preform is heated such that a starting position of a meniscus portion is higher in its position than the top of the primary heater, wherein the meniscus portion is created at the bottom portion of the optical fiber preform.

Abstract: A method for forming an optical fiber includes drawing the optical fiber from a glass supply and treating the fiber by maintaining the optical fiber in a treatment zone wherein the fiber is cooled at a specified cooling rate. The optical fiber treatment reduces the tendency of the optical fiber to increase in attenuation due to Rayleigh scattering, and/or over time following formation of the optical fiber due to heat aging. Methods for producing optical fibers along nonlinear paths incorporating fluid bearings are also provided thereby allowing for increased vertical space for the fiber treatment zone.

Abstract: A method for producing an optical fiber that includes a method for producing an optical fiber, said method comprising: (i) drawing a bare optical fiber from a preform along a first pathway at a rate of at least 10 m/sec; (ii) contacting said bare optical fiber with a region of fluid in a fluid bearing and redirecting said bare optical fiber along a second pathway as said bare optical fiber is drawn across said region of fluid cushion; (iii) coating the bare optical fiber; and (iv) irradiating said coated fiber in at least one irradiation zone to at least partially cure said coating, while subjecting the optical fiber to UV light.

Abstract: Methods for producing optical fibers along nonlinear paths include incorporating fluid bearings. An optical fiber is drawn from a preform along a first pathway, contacted with a region of fluid cushion of a fluid bearing, and redirected along a second pathway as the fiber is drawn across said region of fluid cushion.

Abstract: Inorganic fiber production processes and systems are disclosed. One process includes providing a molten inorganic fiberizable material, forming substantially vertical primary fibers from the molten material, and attenuating the primary fibers using an oxy-fuel fiberization burner. Other processes include forming a composition comprising combustion gases, aspirated air and inorganic fibers, and preheating a fuel stream and/or an oxidant stream prior to combustion in a fiberization burner using heat developed during the process. Flame temperature of fiberization burners may be controlled by monitoring various burner parameters. This abstract allows a searcher or other reader to quickly ascertain the subject matter of the disclosure. It will not be used to interpret or limit the scope or meaning of the claims. 37 CFR 1.72(b).

Abstract: An apparatus includes: an introducer to introduce a glass optical fiber that has passed a pulling mechanism pulling, to draw the glass optical fiber, one end of an optical fiber preform that has been fused by heating; a shredder including a casing connected to the introducer and a shredding mechanism to shred the glass optical fiber introduced by the introducer in the casing into glass optical-fiber pieces; a pipe connected to the casing of the shredder and to carry the glass optical-fiber pieces; and a suction unit connected to the pipe and to suction the glass optical-fiber pieces via the pipe.

Abstract: An induction furnace capable of drawing large diameter preforms of up to 130 mm is described. The induction furnace has top and bottom chimneys surrounding the entire preform during operation of the furnace with an inert conditioning gas which is introduced into the top chimney and flows downward through the furnace body and bottom chimney without significant turbulence. A distributor ring inside the top chimney redirects flow from a circumferential direction to a downward direction. The top chimney also includes a resilient seal to releasably hold the top of the preform. The bottom chimney has a smoothly decreasing cross-sectional area preventing turbulence at the furnace exit. The furnace insulation is preferably a rigid self-supporting graphite cylinder. A method of drawing large diameter preforms either to an optical fiber or to a preform of smaller diameter using such a furnace is also described.

Abstract: Apparatus and methods for making a continuous fiber product by gathering a plurality of fibers into a strand in contact with a pad wheel that is driven with a low voltage, variable speed motor or drive, and controlling the RPM of the motor in response to a breakout detector. Other embodiments further include accelerating the RPM of the motor and pad wheel at a desired ramp-up rate following the resumption of desired fiberization.

Abstract: Drawing methods and drawing furnaces for drawing an optical fiber with small non-circularity by simple drawing system are provided. An optical fiber preform is received into a muffle tube and heated by a primary heater placed to surround the muffle tube. The optical fiber preform is heated such that a starting position of a meniscus portion is higher in its position than the top of the primary heater, wherein the meniscus portion is created at the bottom portion of the optical fiber preform.

Abstract: Optical fiber preforms which can be drawn into optical fibers of desired dimensions are fabricated by applying a vacuum to a cladding tube and drawing molten glass from a crucible into a bore of the cladding tube while a portion of the cladding tube is within a furnace preferably through a small hole in the top of the furnace. The method and apparatus are particularly applicable to highly non-linear fiber (HNLF) glasses and highly doped or rare earth glasses since materials therein are generally expensive and only a small quantity of molten glass is required but can be applied to virtually any optical fiber construction where the core glass has a lower melting or softening point than that of the cladding tube. Sources of contamination, breakage and other preform defects are substantially avoided and toxic substances, if present are readily confined.

Abstract: Methods for producing a coated optical fiber may include drawing an optical fiber from a draw furnace along a first pathway and redirecting the optical fiber along a second, different pathway which is non-parallel with the first pathway. The optical fiber may be coated as it travels along the second pathway.

Abstract: A furnace for drawing an optical fiber includes a body having an upper and lower openings for supplying a preform and discharging a drawn optical fiber, a heating unit installed in the body for receiving and melting the preform, an atmosphere blocking tube installed to the lower opening for discharging the drawn optical fiber and blocking the optical fiber from the atmosphere, an upper introduction port formed at an upper portion of the body for introducing an inert gas toward the preform and partially discharged outside through a gap between the preform and the upper opening, a central and lower introduction ports formed at central and lower portions for introducing an inert gas into the body, a first flow guiding means for guiding the inert gas introduced through the central introduction port upward and then flowed down along a surface of the preform, and a second flow guiding means for guiding the inert gas introduced through the lower introduction port upward and then discharged outside through the atmosp

Abstract: A holey fiber includes a core region and a cladding region surrounding the core region and having air holes arranged around the core region. The cladding region includes an inner cladding layer surrounding the core region and an outer cladding layer surrounding the inner cladding layer. Furthermore, viscosities of the core region and the inner cladding layer are set lower than a viscosity of the outer cladding layer.

Abstract: Large-mode-area single material holey fiber tapers with collapsed by nonadiabatic process air holes in the waist for fiber optic sensors and a method for manufacturing these tapers are claimed. The gradual collapsing of the holes is achieved by tapering the fibers with a “slow-and-hot” method. This nonadiabatic process makes the fundamental mode of the holey fiber to couple to multiple modes of the solid taper waist. Owing to the beating between the modes, the transmission spectra of the tapered single material holey fibers exhibit several interference peaks. That means the all-fiber Mach-Zehnder type interferometer is formed in a holey fiber such a way. The multiple peaks, combined with a fitting algorithm, allow high-accuracy refractometric measurements, temperature-independent strain measurements, measurements of high temperature and may be used for measuring many others parameters.

Abstract: An optical cable is manufactured in a single continuous process starting directly from at least an optical perform, by means of a fiber/cable integrated manufacturing line (50) including a fiber(s) drawing assembly (100) for the production of one or more optical fibers from respective optical preforms, and a cabling assembly (200) for producing the optical cable from the optical fiber(s), the cabling assembly comprising a fiber buffering assembly (200a) for the application of a loose or tight coating to the optical fiber(s), and a strengthening and sheathing sub-assembly (200b) for applying one or more reinforcing and protective layers to the buffered optical fiber(s).

Abstract: There is provided an apparatus and method for fabricating a holey optical fiber. An optical fiber with air holes of a predetermined size and shape along the length of the optical fiber is drawn by supplying nitrogen gas into air holes through one end of a holey optical fiber preform while heating the other end of the preform.

Abstract: In a method of fabricating an optical fiber comprising a silica-based glassy material deuterium is injected in a fiber drawing device. Defect centers generated during the fiber drawing are occupied by deuterium atoms.

Abstract: A furnace for drawing an optical fiber includes a body having an upper and lower openings for supplying a preform and discharging a drawn optical fiber, a heating unit installed in the body for receiving and melting the preform, an atmosphere blocking tube installed to the lower opening for discharging the drawn optical fiber and blocking the optical fiber from the atmosphere, an upper introduction port formed at an upper portion of the body for introducing an inert gas toward the preform and partially discharged outside through a gap between the preform and the upper opening, a central and lower introduction ports formed at central and lower portions for introducing an inert gas into the body, a first flow guiding means for guiding the inert gas introduced through the central introduction port upward and then flowed down along a surface of the preform, and a second flow guiding means for guiding the inert gas introduced through the lower introduction port upward and then discharged outside through the atmosp

Abstract: An apparatus for drawing a fiber (11), particularly an optical glass fiber, from a heated preform (9), has a tubular heating element (1), which encloses preform (9) at least partly in its longitudinal direction, and an induction coil (4) surrounding tubular heating element (1) at a radial distance. Along an inside surface (19) of the tubular heating element (1) a protective tube (20) is provided, which surrounds fiber (11) and preform (9) at a radial distance. Protective tube (20) reliably prevents burning off of the heating element and thus a deterioration of the properties of the fiber (11).

Abstract: A device for continuously twisting an optical fiber, which can add a sufficient twist to an optical fiber, is provided. Reciprocating rollers reciprocate so that the moving direction would be opposite each other along a center axis of rotation. The optical fiber passes through a gap between the reciprocating rollers and runs in contact with the outer circumferential surface of respective reciprocating rollers in order. Reciprocation of the reciprocating rollers adds a twist to the optical fiber. When &phgr; is a contacting angle between the optical fiber and the reciprocating rollers, F is maximum static friction of the optical fiber against the outer circumferential surface of the reciprocating rollers, and T is tension of the optical fiber, the coefficient of friction &mgr; between the optical fiber and the outer circumferential surface of the reciprocating rollers is lead from an operational formula of &mgr;=(1/&phgr;)·ln(F/T).

Abstract: An end heating and processing method of an optical fiber preform. In this method, an optical fiber preform is processed by heating and melting an end of a vitrified optical fiber preform including a core portion and a cladding portion formed on an outer circumference thereof to process the end having a shape for drawing as an optical fiber.

Abstract: Furnace assemblies are provided including a furnace defining an internal process chamber extending therethrough. A first gas screen is coupled to the furnace. The first gas screen is configured to introduce a first gas into the internal process chamber at a first end of the furnace. A second gas screen is positioned adjacent to the first gas screen at an opposite end of the first gas screen from the furnace. The second gas screen is configured to introduce a second gas to provide a seal for the first end of the furnace. The furnace may be a draw furnace and the process chamber may be an internal draw chamber.

Abstract: The invention relates to a device for drawing optical fibers from a preform, comprising: a furnace comprising a tube for heating one end of said preform to the drawing temperature thereof, which tube comprises: i) a central tube, ii) an upper extension tube connected to the lower part of said central tube so as to obtain a gas tight seal against an ambient atmosphere exterior said furnace, wherein the upper extension tube comprises an inlet for an inert gas in the top region of the upper extension tube, as a result of which the preform and the fiber to be drawn therefrom are surrounded by an inert gas, iii) a lower extension tube connected to said upper extension tube in such a manner that a gas tight seal against an ambient atmosphere exterior said furnace is obtained, iv) a tube outlet connected to said lower extension tube, means for drawing the fiber, means for supporting the preform in the furnace.

Abstract: An optical fiber drawing furnace, comprising a furnace core tube where an optical fiber preform is inserted, fused with heat by a cylindrical heating element that is provided around the furnace core tube, and drawn to an optical fiber, wherein a protective tube is provided being contacted with an upper end edge of the furnace core tube.

Abstract: An apparatus for receiving and automatically moving a moving strand of fibers from a starting position to any one of a plurality of predetermined positions in a multi-grooved separator roll is disclosed. This apparatus is particularly in processes of making continuous fiber products from molten material and replaces a manual operation that presented safety problems.

Abstract: An apparatus for drawing a fiber (11), particularly an optical glass fiber, from a heated preform (9), has a tubular heating element (1), which encloses preform (9) at least partly in its longitudinal direction, and an induction coil (4) surrounding tubular heating element (1) at a radial distance. Along an inside surface (19) of the tubular heating element (1) a protective tube (20) is provided, which surrounds fiber (11) and preform (9) at a radial distance. Protective tube (20) reliably prevents burning off of the heating element and thus a deterioration of the properties of the fiber (11).

Abstract: An inlet arrangement for inserting a preform (3′) into a furnace (1′) for drawing a fiber (2′). The furnace includes an enclosure (4′) at the top of which there are both an opening to allow insertion of a preform which moves in translation, and a preform inlet arrangement (13′). The inlet arrangement comprises both an injector (6′) situated at the level of the opening to inject inert gas around the preform and to fill the enclosure, and at least one seal (17B) fixed above the injector and designed to allow the preform to pass therethrough, with its cylindrical main body (9′) being surrounded. The inlet arrangement further comprises an airlock (13) for closing and sealing the top of the furnace, above the injector, whether a preform is present or absent, which airlock is pressurized to prevent the surrounding air entering. The rods of the equipped preforms carry respective continuity tubes (20) of the same diameter as the bodies.

Abstract: An apparatus for receiving and automatically moving a moving strand of fibers from a starting position to any one of a plurality of predetermined positions in a multi-grooved separator roll is disclosed. This apparatus is particularly in processes of making continuous fiber products from molten material and replaces a manual operation that presented safety problems.

Abstract: A furnace body for a glass preform elongating apparatus which makes an elongated body by passing the glass preform through the furnace body and elongating the glass preform while heating the glass preform, the furnace body comprising a furnace core tube shaped like a cylinder through which the glass preform passes and having so adequate length in an axial direction that the elongated body may not bend or distort its form, a heating member disposed at an outer peripheral portion of the furnace core tube, a thermal insulator enveloping the furnace core tube and the heating member from outside in circumferential and axial directions thereof, and a furnace body outer shell holding the thermal insulator therein, wherein a through hole is disposed near the heating member downstream thereof in an advancing direction of the glass preform so as to penetrate through the furnace core tube, thermal insulator, and furnace body outer shell in the direction orthogonal to the furnace core tube.

Abstract: Apparatus and methods of using the apparatus to automate a labor intensive portion of the process of making continuous fiber products, like chopped glass fiber. In this process many fiberizers are used, each fiberizer forming as many as several thousand fibers. Fibers break frequently requiring the fiberizers to be restarted and this has always been a labor intensive part of the process. Apparatus for getting the fiberizers ready to restart quickly and for forming a fiber strand, apparatus for gripping the strand, breaking it and transporting it to strand pulling and processing equipment and apparatus for moving a newly started strand into a desired position on an optional strand separating and guiding means, and methods of using the apparatus are disclosed.

Abstract: A device for drawing down an optical fiber preform (2) connected at one end to a feed rod (3) having an equal or smaller diameter. A chamber (11) in which the preform is drawn has an upper part (11A) with an opening (12). The opening engages the preform to seal the chamber. An enclosure (5) has a seal (6) at its upper part (5A) for sealing around the feed rod. A lower part (5B) of the enclosure contacts the upper part of the chamber to seal the chamber while the feed rod is passing through the opening.

Abstract: A multi-screen mixing apparatus for installation in a fiber-forming bushing used in the manufacture of glass fibers. The multi-screen mixer attaches to the walls of the bushing, and includes a first screen having openings therein through which the glass flows and a second screen having openings through which the glass flows longitudinally spaced from the openings in the first screen such that the molten glass must flow in a non-linear path as it passes through the screens. Additional screens can be added to cause additional flow diversion to further mix the molten glass.

Abstract: This invention provides a method of increasing adhesion of radiation-cured, inner primary coatings on glass optical fibers. A glass optical fiber drawing tower has a controllable variable amperage electron beam for exposing different sections of a glass optical fiber with different amperage levels of electron beam radiation. The different sections of the glass optical fiber after being exposed to the selected amperage levels of electron beam radiation are then coated with an inner primary coating composition which is finally cured by exposure to actinic radiation. Later formed sections of the same glass optical fiber can be exposed to different amperage levels of electron beam radiation and then coated and cured. The different sections of the glass optical fiber which have been coated with an inner primary coating using this method demonstrate correspondingly different degrees of coating adhesion. Reduced levels of adhesion promoter are required for inner primary coating compositions when using this method.

Abstract: An apparatus is provided for producing a glass fiber package. The apparatus includes a heated bushing for supplying streams of molten glass to be drawn into continuous fibers, a rotatable member adapted to draw the streams into fibers and to wind the fibers into a package, an applicator for applying a size to the fibers, and a drying device including a heated element maintained at a temperature of between about 1000.degree. F. and 1500.degree. F. for contacting and transferring energy in the form of heat to the sized fibers to dry the fibers before they are wound into the package. The heating member is stationary while contacting the sized fibers.

Abstract: A method and apparatus are provided for drawing a self-aligned core fiber free of surface contamination and inserting the core fiber into a cladding material to make an optical fiber preform. Single or multi-mode optical fibers having high quality core-clad interfaces can be directly drawn from the preforms described herein.

Abstract: A glass preform for an optical fiber is effectively drawn by connecting dummy rods to both ends of the glass preform and connecting the dummy rods to fitting members.

Abstract: An apparatus is provided for applying a tensile force along the longitudinal axis of a cane assembly during the deposition of soot thereon to produce an optical fiber preform. Fiber drawn from such a preform exhibits improved core/clad concentricity. The tensile force may be applied at one or both ends of the cane assembly, with application at both ends being preferred. The tensile force may be varied during the deposition of soot. The cane assembly may be annealed prior to beginning the deposition of soot thereon.

Abstract: A method and apparatus are provided for forming a glass preform which can be directly drawn into a single or multi-mode optical fiber. Single or multi-mode fibers drawn from the preforms described herein have high quality core-clad interfaces since the core and cladding materials are not exposed to crystallization temperatures upon the addition of the core material to cladding material.

Abstract: A capstan belt (80) is mounted on a pair of pulleys (82,83) for engagement with the surface of a draw capstan (75), the capstan belt (80) being driven for rotation on the pair of pulleys (82,83) by rotational movement of the capstan (75). A coated optical fiber (35) is drawn between the capstan (75) and the capstan belt (80). At least a surface of the capstan belt (80) is manufactured of a very low modulus material which easily deforms when contacting the coated optical fiber (35) such that the belt material deforms rather than the coating on the fiber during contact between the belt and the coated fiber. An idler belt (78) may surround the capstan (75) and an idler pulley (79), at least the surface of the idler belt (78) being manufactured of the same or similar material as the capstan belt (80). The belt material has a modulus of elasticity in the range of 10 to 200 PSI (0.07 to 1.38 MPa) at 10% strain and 200 to 5000 PSI (1.38 to 34.5 MPa) at 100% strain.

Abstract: A process and apparatus are provided for coating a sizing composition onto glass fibers. The apparatus includes an applicator for applying a liquid sizing composition to the glass fibers and a treatment station for treating the sized fibers to increase the viscosity of the sizing composition, thereby improving the adherence of the sizing composition to the fibers.