Abstract: A system for automated production of a fiber optic device includes a chamber regulating an environment and/or atmosphere within for the automated production of the fiber optic device. The system also includes a sealable input port, communicating with the chamber and substantially sealing the environment and the atmosphere of the chamber. The sealable input port receives an optical fiber for insertion therethrough into the chamber. A movable holding stage is included within the chamber, including at least one clamp to be secured to the optical fiber. An energy source is disposed within the chamber, and used to apply energy to the optical fiber. The system also includes a gripping device within the chamber. The gripping device includes a cavity adapted for receiving the optical fiber therethrough and for securing thereto.

Abstract: A method and apparatus are provided for removing protective coating material from a fiber optic cable including one or more optical fibers. A stream of hot inert gas is directed onto the cable to soften the protective coating material and blow it from the cable. The stream can be moved relative to the cable until the desired length of coating material has been removed.

Abstract: In a method for molding glass products having a fine structure as of an optical fiber holder with a high size precision, a mold used for the molding has the fine structure in a size such that a size difference occurring when the glass product is cooled down to a room temperature where at the end of molding with a pressure a size of the fine structure of the mold for glass product and a size of a fine structure of the glass product formed by transfer of the fine structure of the mold are the same as one another is so adjusted that a size of the fine structure of the completed glass product falls within a permissive size precision range. The mold may has a size satisfying, as a size of a fine structure at a room temperature, a formula [1+(.alpha.g-.alpha.m).times..DELTA.T+.alpha.g'.times..DELTA.T'].times.Sg, wherein Sg denotes a size of a fine structure of thc glass product at the room temperature; .alpha.

Abstract: Process for making preforms for multicore optical fibers. According to this process, several elementary preforms are made, a first machining is performed on them such that a chosen geometric model will be obtained after they are assembled, a second machining is performed such that the assembly (11) has at least one hole (12), the preforms are assembled and an induction furnace (18) is used to fuse the preforms, while creating a vacuum in each hole.

Abstract: A manufacturing method for a glass product not having a rotatively symmetric body like an optical fiber fixing member but having a fine structure as of optical fiber engagement portions, to transfer the fine structure with a high precision without creating molding burrs, includes the steps of placing a glass material in a cavity defined by a lower mold, an upper mold, and a side mold, molding the glass material in the cavity with pressure into the glass product in so controlling that the glass material has a viscosity range of 10.sup.6.5 to 10.sup.9.

Abstract: A method of patterning a plurality of optical rods includes bonding a plurality of optical rods into an array wherein each of the optical rods is aligned so that an exposed end face of each of the optical rods is oriented in a common direction. The exposed end faces of the optical rods are patterned so that each of the exposed end faces has a three-dimensional pattern formed thereon. These patterned optical rods can then be separated and used in the fabrication of optical systems.

Abstract: A method and apparatus are provided for removing protective coating material from a fiber optic cable including one or more optical fibers. A stream of hot inert gas is directed onto the cable to soften the protective coating material and blow it from the cable. The stream can be moved relative to the cable until the desired length of coating material has been removed.

Abstract: A method of manufacturing a multi-core optical fiber, the method including assembling together a plurality of substantially identical single-core optical fiber preforms (2', 2"), referred to as "single-core preforms", each of which includes a core bar (3) surrounded by a layer of optical cladding (4), so as to form a "multi-core preform" (10) and drawing down the multi-core preform (10) so as to obtain the multi-core optical fiber. The assembly step includes securing the single-core preforms (2', 2") to one another by fusing them over their entire lengths or over portions thereof along their tangential lines of contact (T), without inserting the multi-core preform (10) into a holding tube. A vacuum is maintained in the preform during the drawing step, the vacuum being formed before or during the drawing step.

Abstract: A method for constructing a glass fiber imaging bundle includes drawing a continuous glass fiber from a dispenser. The dispenser is mounted for movement parallel to a drum having first, second, and third areas around the drum's circumference. The fiber is affixed to the drum at a location in the first area. The drum continuously rotates during the present process as the fiber is wound around the surface of the drum in the second area. The dispenser moves from a location adjacent to the first area to a location adjacent the third area. Once a ribbon is created, the fiber is dispensed to a location in the third area. The fiber is affixed to the surface of the drum in the third area, and the fiber is then dispensed from the third area to a second location in the first area. The fiber transversing the second area is cut and removed from the surface of the drum.

Abstract: A method for making a fused fiber bundle by providing a bundle of optical fibers, heating the fibers by a flame extending axially along the bundle, and translating the flame axially along the fibers. Tension may be applied to the heated bundle to reduce the diameter of the bundle.

Abstract: The end portions of a plurality of optical optical fibers are stripped; the coated portions of the fibers constituting pigtails. The stripped portion of one of the fibers is fused to an uncoated fiber section having a diameter that is larger than that of the stripped fiber end portions. A fiber optic coupler preform is made by surrounding the uncoated fiber section with the stripped portions of the remaining fibers to form a close-packed fiber array. At least a portion of the overlapping region of the uncoated fiber section and the stripped end portions is heated and drawn to induce the coupling of optical signals between the uncoated fiber section and the stripped portions.

Abstract: A method of manufacturing a multi-core optical fiber, the method including assembling together a plurality of substantially identical polished single-core optical fiber preforms (2', 2"), referred to as "single-core preforms", each of which includes a core bar (3) surrounded by a layer of optical cladding (4), so as to form a "multi-core preform" (10), and drawing down the multi-core preform (10) so as to obtain the multi-core optical fiber. The assembly step includes securing the single-core preforms (2', 2") to one another by fusing them over their entire lengths or over portions thereof along their tangential lines of contact (T), without inserting the multi-core preform (10) into a holding tube. A vacuum is maintained in the preform during the drawing step, the vacuum being formed before or during the drawing step.

Abstract: The present invention provides fiber optic couplers for use with at least three optic fibers. The optic fibers arranged in a linear array, that is, the optic fibers are coupled side by side. The fibers along either end of the linear-array are coupled only to a single fiber, while the remaining fibers are generally coupled between only two adjacent fibers. Generally, at least one of the fibers has a propagation constant different than the other fibers. Such variations in the propagation constant are used to vary the coupling coefficients among the fibers of the linear-array, thereby providing a repeatable mechanism, to vary coupled power ratios among the fibers of the coupler. Theoretical calculations and empirical experience have shown that varying the propagation constant of fibers among a linear-array, generally by pre-pulling the fibers by varying amounts, allows repeatable manufacturing of 1.times.3, 3.times.3, 1.times.4, 4.times.4, 1.times.N and even N.times.

Abstract: A method and device is provided wherein a reinforcement is provided for one or more optical fibers. One or more fibers are inserted into a sleeve made of a material that is substantially the same as the material of the cladding of the one or more optical fibers. The bore of the sleeve is sized to accommodate the one or more optical fibers; After the one or more optical fibers is inserted into the sleeve sufficient heat is applied to the sleeve for a duration to collapse the sleeve onto the one or more optical fibers. Preferably, the sleeve is a glass pre-form consisting substantially of 90% or greater silica.

Abstract: Optical fibers are fixed to elongating tables by optical fiber fixing jigs. Coatings are removed from portions of the fibers and respective fibers of two different groups are placed into tight contact with one another. The fibers are then heated by a gas burner 4A so as to be welded integrally with each other, and are then elongated. In one preferred embodiment, the fibers are arranged such that there are gaps therebetween. These gaps are substantially 250 .mu.m. The gaps are sufficiently wide that heating gas flows in a manner such that all the optical fiber strands are heated uniformly to make it possible uniform welding and elongation.

Abstract: A method of bonding glass-based optical elements comprising the steps of positioning a first glass-based optical element relative to a second glass-based optical element, applying a glass-based bonding compound about the first and second optical elements, and applying sufficient localized heat to the glass-based bonding compound to cause the glass-based bonding compound to soften and fuse with the optical elements.

Abstract: The present invention provides a method for manufacturing an optical fiber coupler in which an optical fiber is elongated and heated by using a heating source under a constant tension. The heat source is controlled based on the ratio of a target elongating speed and an actual elongating speed of the optical fiber.

Abstract: Overclad fiber optic couplers are made by inserting the uncoated portions of a plurality of optical fibers into the bore of a glass tube, collapsing the tube midregion onto the fibers and stretching the central portion of the tube midregion. The present method utilizes a glass tube the bore of which includes a circular portion and a recess. A plurality of optical fibers are sequentially inserted into the tube by threading the coated end into the circular bore portion until the uncoated portion of fiber is centered in the tube. The uncoated portion of fiber is then transferred laterally into the bore recess. After all fibers have been threaded into the circular bore portion and transferred to the recess, a filler fiber is inserted into the circular bore portion. The resultant coupler exhibits low excess loss.

Abstract: A varied ratio coupler, and a method of forming the same, constructed and arranged, in a unitary structure, to cause optical power in an input optical fiber to couple asymmetrically to at least two output optical fibers in a manner establishing different insertion losses between the input fiber and at least two output optical fibers. The coupler includes a central fiber surrounded by a close-packed ring of fibers. In certain preferred embodiments, the coupler has a bend that lies in a preselected plane and has a radius of curvature that is selected to provide the above difference in the insertion losses.

Abstract: Overclad fiber optic couplers typically include an elongated glass body having a solid midregion through which at least two glass optical fibers extend in optical signal coupling relationship. At each end of the midregion is an end region containing a bore from which optical fiber pigtails extend. In accordance with the invention, each end region includes a first projecting portion, one surface of which forms a ledge. That end of each bore opposite the midregion terminates at a recessed face that intersects the respective ledge. One end of at least the first fiber extends from the first bore. That portion of the first fiber outside the first bore has a coating that extends along the ledge, the coating terminating outside the first bore. A mass of glue extends between the ledge and the recessed face and encompasses the bare portion of the first fiber that extends along the first ledge and at least a portion of the first coating that extends along the first ledge.

Abstract: Optical fibers are fixed to elongating tables by optical fiber fixing jigs. Coatings are removed from portions of the fibers and respective fibers of two different groups are placed into tight contact with one another. Rectifier rods, supported movably by rectifier rod supporting members, are disposed outside the optical fiber strands. The fibers are then heated by a gas burner 4A so as to be welded integrally with each other, and are then elongated. By using rectifier rods, the outside optical fiber strands of the groups being welded are not so strongly heated that uniform welding and elongation can be realized. In one preferred embodiment, the fibers are arranged such that there are gaps therebetween. These gaps are substantially 250 .mu.m. The gaps are sufficiently wide that heating gas flows in a manner such that all the optical fiber strands are heated uniformly to make it possible uniform welding and elongation.