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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

Abstract: A method and apparatus for producing glass fibers wherein molten glass is deposited onto a spinning cup structure. Centrifugal force urges the molten glass outwardly and upwardly along the inner surface of an upstanding wall of the cup structure. The glass is then extruded through small holes in the cup wall. A downflowing stream of hot gas passes downwardly along the outer surface of the cup wall to turn the fibers downwardly while producing an attenuation (reduction) of fiber diameter. The lower portion of the cup side wall is heated to achieve greater temperature uniformity of the fibers as they are formed. A cool gas curtain is formed about the downflowing hot gas stream to somewhat concentrate the hot gas stream for more uniform heating of the downflowing glass fibers.

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.