Patents Examined by Robert L. Lindsay
  • Patent number: 5482525
    Abstract: A method of producing an elliptic core type polarization-maintaining optical fiber comprises the steps of providing a glass rod comprising a cladding glass layer around the periphery of a core glass layer, the cladding glass layer having a softening point higher than the softening point of the core glass layer, removing two side surface portions of the glass rod by machining along the axial direction of the glass rod to form a machined rod noncircular in cross section, outside depositing fine silica glass particles on the periphery of the machined rod, followed by sintering to provide a support glass layer having a softening point higher than the softening point of the cladding glass layer, and drawing the thus obtained glass rod body as an optical fiber preform. Since the portion for constituting the core of the optical fiber is formed by machining, the core is permitted to have a high ellipticity.
    Type: Grant
    Filed: May 28, 1993
    Date of Patent: January 9, 1996
    Assignee: Hitachi Cable Limited
    Inventors: Hiroshi Kajioka, Kohdo Yamada, Masashi Nakamura, Kazuya Murakami, Yuuetsu Takuma
  • Patent number: 5395412
    Abstract: A method and apparatus for the treatment of fiber pieces, with which the fiber pieces (24) in a gas/solid mix are fed through a transport line (11) into a heating device (14). Inside the heating device (14) the exposed ends of the fiber pieces (24) are rounded off and/or thickened. Subsequent to the treatment in the heating device the treated fibers (25) flow into a feed line and from there into a separating device (18), in which the gas/solid mix is separated. The fiber bits produced according to the invented method improve the mechanical quality and characteristics of fiber composite materials considerably. By utilizing the described device the invented method can be carried out most economically. (FIG.
    Type: Grant
    Filed: July 9, 1993
    Date of Patent: March 7, 1995
    Assignee: Poly ID AG
    Inventors: Peter Eyerer, Peter Stockmayer, Rolf Weigele
  • Patent number: 5392375
    Abstract: A process for producing a glass having a rod refractive index distribution, which includes pressing a glass at a temperature below the glass transition temperature to form a glass having a density increased towards the surface layer thereof, or alternatively includes heating a glass at a temperature around the transition temperature at the lowest to prepare glass having a uniformly enhanced density and heating the treated glass under a pressure lower than the applied pressure at a temperature below the glass transition temperature of the glass to prepare a rod glass having a density increased towards the central portion.
    Type: Grant
    Filed: August 9, 1993
    Date of Patent: February 21, 1995
    Assignee: Agency of Industrial Science and Technology
    Inventors: Naoyuki Kitamura, Kenichi Kinugawa, Jun Matsuoka, Kohei Fukumi, Isao Kondoh, Saburo Kose, Hiroshi Yamashita, Makoto Kinoshita
  • Patent number: 5385595
    Abstract: A durable, corrosion-resistant fiberglass spinner is prepared by applying a uniform layer of titanium nitride to the bores of the spinner by chemical vapor deposition, and applying over the layer of titanium nitride a layer of platinum by transient liquid phase deposition.
    Type: Grant
    Filed: December 23, 1993
    Date of Patent: January 31, 1995
    Assignee: Owens-Corning Fiberglas Technology Inc.
    Inventor: Dennis L. McGarry
  • Patent number: 5383946
    Abstract: In a heating furnace an optical fiber preform is heated and the optical fiber is drawn. The obtained optical fiber is cooled by a cooling gas in a cooling apparatus provided beneath the heating furnace, then a resin is coated on the outer circumference of this optical fiber by a resin coater. At this time, the blowing direction of the cooling gas blown out from the optical fiber inlet of the cooling apparatus is inclined exactly by a predetermined angle (.theta.) with respect to the axial line of the running optical fiber. As a result, even if no rise suppression gas is used, it is possible to prevent the cooling gas blown upward from the cooling apparatus from entering into the heating furnace and thereby to prevent the lowering of the quality of the optical fiber due to the adhesion of dust. Also, a cooling apparatus container enclosing the cooling apparatus is provided.
    Type: Grant
    Filed: June 16, 1993
    Date of Patent: January 24, 1995
    Assignee: The Furukawa Electric Co., Ltd.
    Inventors: Yasuhiro Naka, Yukio Komura
  • Patent number: 5383948
    Abstract: This invention relates to a method and apparatus for cracking off glass attached to, or comprising a portion of, the constricted end (neck) of the glass funnel component of a glass cathode ray tube and thereafter sealing a replacement glass neck component to the funnel component. A gauge and sensor mechanism are used to produce a signal representative of the location of a defined plane through the funnel. This signal is sent to a central processing unit which controls the apparatus so that the cracking off of the old neck and subsequent sealing of the new neck take place at that defined plane. In this way, the individual method steps are integrated into an automated process.
    Type: Grant
    Filed: July 6, 1993
    Date of Patent: January 24, 1995
    Assignee: Corning Incorporated
    Inventor: Lance P. Muir
  • Patent number: 5382276
    Abstract: A method of cutting an optical fiber ribbon obliquely, the ribbon being constituted by a plurality of optical fibers that are all parallel to a "longitudinal" axis of the ribbon, the fibers all being situated in the same horizontal plane referred to as the plane of the ribbon, and being protected by a common sheath, the method comprising the following steps:a portion of the ribbon is stripped of its sheath;the ribbon is held stationary at two points situated on either side of the stripped portion;a curved anvil is advanced along a displacement axis orthogonal to the horizontal plane so as to tension the portion in such a manner as to incline a part of the stripped portion relative to the horizontal plane; anda cutter is advanced facing the anvil and along a displacement axis parallel or coinciding with that of the anvil to cut the stripped portion in the inclined part.
    Type: Grant
    Filed: July 20, 1993
    Date of Patent: January 17, 1995
    Assignee: Mars Actel
    Inventors: Roland Hakoun, Michel Reslinger
  • Patent number: 5382275
    Abstract: A method for fusion-forming an optical signal attenuator using a piece of optical fibre, comprising essentially the following steps:a) fusing the piece of optical fibre;b) manipulating the piece of optical fibre during fusion;c) inserting the piece of optical fibre into a mechanical adaptor for connection to two standard connectors butt-coupled respectively to the ends of two optical fibres, wherein the manipulation of the piece of optical fibre during fusion is effected by subjecting the piece of optical fibre to both axial misalignment and angular misalignment.
    Type: Grant
    Filed: June 16, 1993
    Date of Patent: January 17, 1995
    Assignee: Sirtl S.p.A.
    Inventors: Marco Decao, Aurelio Pianciola, Tiziana Tambosso
  • Patent number: 5378256
    Abstract: This invention describes a method of manufacturing silica waveguide optical components in which silica glass films are laminated on a substrate by repeating a unit operation in which a sol material, a precursor of glass particles, is coated and then the coated layer is heated in an oxygen atmosphere. wherein the heating temperature is controlled in such a manner that the radius of curvature of warping of the substrate is 2 m or more after the coated layer is heated, thereby preventing cracking in the formed silica glass film and/or peeling of the coated layer. At locations where a difference in height is present, at least when sol is coated first time, the thickness of the coated layer is less than that of one of the subsequent coated layers.
    Type: Grant
    Filed: June 16, 1993
    Date of Patent: January 3, 1995
    Assignee: The Furukawa Electric Co., Ltd.
    Inventors: Mino Green, R. R. A. Syms, Andrew S. Holmes, Ken Ueki, Hisaharu Yanagawa
  • Patent number: 5374291
    Abstract: A method of processing a photosensitive glass includes exposing. Photosensitive glass by radiation from a laser whose oscillation wavelength lies within the range of wavelengths of exposing light to which the glass responds. Then, the exposed portions 1c are thermally developed and etched. Since a laser beam propagates with a high rectilinearity, the front and rear surfaces of thick photosensitive glass can be exposed without producing dimensional errors. Therefore, the etching accuracy is improved. Especially, where the front and rear surfaces of photosensitive glass are etched, both surfaces can be processed so as to form the same shape in them accurately. In addition, because almost all the energy of the laser radiation is used for exposure of the photosensitive glass, the energy is not wasted and so the efficiency is high.
    Type: Grant
    Filed: May 21, 1993
    Date of Patent: December 20, 1994
    Assignees: Director-General of Agency of Industrial Science and Technology, Seikosha Co., Ltd.
    Inventors: Akira Yabe, Hiroyuki Niino, Nobuhiro Kondo, Hirokazu Ono, Tomoaki Takahashi, Yoshinaga Takahashi, Toshio Matsumura
  • Patent number: 5372625
    Abstract: The method of manufacturing a multiferrule for optical fibers, the method consisting in fiber drawing a preform of silica that includes a plurality of mutually parallel channels, the method being characterized by the fact that said preform is made from a rod (1) of silica having a plurality of longitudinal grooves (3) uniformly distributed about an axis (2) and closed by at least one piece of silica (4) for defining said plurality of channels.
    Type: Grant
    Filed: June 8, 1993
    Date of Patent: December 13, 1994
    Assignee: Mars Actel
    Inventors: Claude Brehm, Jean-Pierre Dumas, Philippe DuPont
  • Patent number: 5372756
    Abstract: A light transmitting body (10), (40) has a longitudinal axis (12), (42), and a light radiating surface (14), (46) extending substantially parallel to the axis (12), (42). Where the body is an optical fiber (10), the light radiating surface is the circumferential surface (14) of the fiber (10). Where the body is a rectangular panel (40), the light radiating surface is a rectangular surface (46) of the panel (40). A plurality of striations (16), (44) are formed in the light radiating surface (14), (46) parallel to the axis (12), (42), which cause light entering the body (10), (40) along the axis (12), (42) to be radiated out of the body (10), (40) through the light radiating surface (14), (46) with substantially uniform intensity along the axis (12), (42). The striations (16), (44) may be formed by molding, cold drawing, heating the body (10), (40) under tension, cutting, or by bundling and fusing a plurality of small optical fibers (90) together.
    Type: Grant
    Filed: May 14, 1993
    Date of Patent: December 13, 1994
    Inventor: Nobuo Oyama
  • Patent number: 5368623
    Abstract: The objective is to provide a process and an apparatus for the continuous production of mineral wool nonwovens, by means of which a stable flow pattern is created in the chute, thus facilitating a clearly defined, homogeneous layer of deposited mineral wool.According to the invention, at least one backflow region (24, 25) is generated in the chute (9) outside the fibre flow (23), which backflow region (24, 25) is sufficient for such a large-volume backflow with such a low mean velocity that appreciable upward fibre transport is avoided. In this connection, a portion (32) of the process air entrained with the fibre flow is deflected upward in the backflow, and another portion (34) of the process air is extracted.
    Type: Grant
    Filed: January 3, 1994
    Date of Patent: November 29, 1994
    Assignee: Grunzweig & Hartmann AG
    Inventors: Klemens Hirschmann, Joachim Mellem
  • Patent number: 5366531
    Abstract: An improvement is proposed in the method for the flame hydrolysis of a silicon-containing gas, e.g., silicon tetrachloride, to produce fine silica particles to be deposited on a substrate in a process for the preparation of a silica glass preform of optical fibers by using a fivefold concentric multiplex-tube burner nozzle. In contrast to the conventional way for the flame hydrolysis in which the center or first nozzle opening of the burner serves for ejection of a mixture of silicon tetrachloride and oxygen and hydrogen is ejected from the third nozzle opening while argon is ejected from the second nozzle opening inbetween, the gas ejected from the second nozzle opening is, instead of argon alone, a mixture of oxygen and argon in a specified mixing proportion so that deposition of silica particles on the nozzle end can be prevented even when the feed rate of silicon tetrachloride is relatively high.
    Type: Grant
    Filed: October 4, 1993
    Date of Patent: November 22, 1994
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Hiroyuki Koide, Hitoshi Iinuma, Hideo Hirasawa
  • Patent number: 5366527
    Abstract: A method and apparatus is provided for controlling the diameter of a coated optical waveguide fiber. The viscosity profile of the coating material is controlled by adjusting the temperature of a portion of the coating assembly based on a measurement of the diameter of the coated fiber. By controlling the viscosity profile of the coating material, the amount of coating applied to the fiber is controlled,, thereby determining the diameter of the coated fiber.
    Type: Grant
    Filed: April 5, 1993
    Date of Patent: November 22, 1994
    Assignee: Corning Incorporated
    Inventors: Lynn G. Amos, Paul A. Chludzinski, Heidi B. Leoni, Johnnie E. Watson, Richard R. Williams
  • Patent number: 5366530
    Abstract: The invention concerns the method and apparatus to fabricate an oval cross-sectional optical waveguide which only allows light to propagate in one direction of polarization. The optical waveguide preform for such an optical waveguide according to the modified chemical vapor deposition (MCVD) process is produced in such a way, that cooling is used to provide the substrate tube with an oval or elliptical temperature cooling profile. The apparatus for carrying out the fabrication method includes a cooling device (5) mounted to a support (3) beside a gas burner (4) and consists of two nozzles (10) directed toward the substrate tube (2) so as to direct cooling gas toward the substrate tube as glass layers are deposited thereon to produce core and cladding of the optical waveguide. The nozzles rotate synchronously with the substrate tube.
    Type: Grant
    Filed: April 13, 1993
    Date of Patent: November 22, 1994
    Assignee: Alcatel, N.V.
    Inventor: Dieter Weber
  • Patent number: 5364427
    Abstract: Bent sol-gel produced tubing is straightened by drawing, with tensile force and operating temperature to result in minimal plastic flow, so that size reduction is small. The method is usefully applied to reject recovery in the preparation of overclad tubes, which as encompassing closely-fitting core rods, form the composite preform from which optical fiber is drawn.
    Type: Grant
    Filed: July 16, 1993
    Date of Patent: November 15, 1994
    Assignee: AT&T Bell Laboratories
    Inventor: James W. Fleming, Jr.
  • Patent number: 5364430
    Abstract: Low attenuation, low dispersion of optical waveguides are provided by a process initiating with axial deposition of a high velocity-core soot stream impinging on a target at a high angle of incidence relative to the axis of rotation of the target. A core cylinder is built up axially by relative movement between the soot stream and target during deposition, the movement being non-constant in order to maintain a substantially constant diameter with a constant deposition rate. A cladding layer is then built up by deposition of soot radially on the core. Subsequent drying and sintering provides a vitreous preform which may be drawn directly into optical waveguides. Alternatively, the sintered product may be drawn down to smaller rods, which then are covered with further deposited soot cladding to a desired final thickness, and after further drying and sintering may be drawn to optical waveguides.
    Type: Grant
    Filed: January 8, 1993
    Date of Patent: November 15, 1994
    Assignee: Cal-Optics, Inc.
    Inventor: Arnab Sarkar
  • Patent number: 5364428
    Abstract: A glass preform which is used for fabricating an optical fiber, has substantially no bubbles therein and contains sufficient amount of fluorine is produced by a method comprising steps of: forming a porous glass soot body from a glass-forming raw material, removing trapped gas and water from pores of the soot body by heating the soot body under pressure lower than several ten Torr. at a temperature at which the soot body is not vitrified, filling the pores of the soot body with a gas containing SiF.sub.
    Type: Grant
    Filed: March 1, 1994
    Date of Patent: November 15, 1994
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Michihisa Kyoto, Yoichi Ishiguro, Akira Urano, Hideo Kakuzen
  • Patent number: 5364426
    Abstract: A glass melter 30 having a mixing impeller 34 for converting a feed stream 38 supplied to a vessel 32 into a vitrified glass melt 50. Heating means such as electrodes 36 or a gas burner 58 are used to heat the glass melt 50. Electrode 36 arrangements are proposed for minimizing current flow through the impeller 34. Current flow through a special continuous circular impeller or conical pump 70 is disclosed. A cylindrical vessel 98, triangular vessel 94, square vessel 32, and hexagonal vessel 96 are disclosed. Methods of processing particular waste streams are disclosed including coated mineral fibers, fly ash, radioactive material, chemical waste and the like.
    Type: Grant
    Filed: September 16, 1993
    Date of Patent: November 15, 1994
    Assignee: Stir-Melter, Inc.
    Inventor: Ray S. Richards