Abstract: A heat processing procedure is used to create reinforcing whiskers of TiO.sub.2 in glass-ceramic materials in the LAS and MAS family. The heat processing procedure has particular application in creating TiO.sub.2 in-situ in a modified .beta.-eucryptite system.

Abstract: In a method of manufacturing a preform for a nonoxide glass fiber, cladding and core glass materials are placed in a cylinder of an extrusion apparatus such that ground end faces of the respective cladding and core glass materials are in contact with each other and such that the cladding glass material is located adjacent a molding section of the extrusion apparatus. The cladding and core glass materials are heated within inert-gas atmosphere, to their respective temperatures equal to or below their respective sag points and equal to or above their respective crystallization start temperatures. An extrusion punch of the extrusion apparatus is pushed within the atmosphere, to extrude the cladding and core glass materials through a molding nozzle in the molding section while the cladding and core glass materials are in fusible contact with each other, thereby forming the preform of a core and cladding structure.

Abstract: A silica-based glass rod is inserted into a space portion of a mold. Then, a slurry, which is obtained by dispersing a silica glass powder material in pure water, is poured into a molding space between the glass rod and the inner surface of the mold, whereby a porous glass shaped body is formed around the glass rod. Drying this shaped body results in a silica glass base material which includes the glass rod and the porous glass shaped body surrounding the same.

Abstract: An optical fiber soot synthesis apparatus which synthesizes around a fiber starting member forming a core of an optical fiber an optical fiber soot forming a cladding and which accurately calculates in real time the mass of the optical fiber soot when deposited so as to control the synthesis of the optical fiber soot. The optical fiber soot synthesis apparatus measures the weight of the rotating fiber starting member and optical fiber soot by a pair of soot weight detection sensors arranged at a fiber starting member support and rotational drive mechanisms divided so as to prevent the weight of the rotational drive mechanisms from having much of an effect. The computation and control apparatus performs operational processing from the measured weights and calculates the mass of only the optical fiber soot synthesized on the fiber starting member in real time. The computation and calculation apparatus refers to the calculated mass to control the synthesis of the optical fiber soot.

Abstract: The invention relates to a method of making multi-ferrules. It provides a method of making multi-ferrules from a vitreous material, the multi-ferrules having a series of cylindrical channels with parallel axes.

Abstract: Disclosed is a material for a tempering process of glass plates utilizing a so-called contact process. It proposes a material with a base of an arrangement of thin metallic threads exhibiting a heat resistance on the order of 0.25.multidot.10.sup.-3 to 2.5.multidot.10.sup.-3 m.sup.2 .multidot.K.multidot.W.sup.-1 intended to be inserted between the cooling plates and the glass of a contact-tempering installation. The process makes it possible to temper glazings sufficiently so that they are used as automobile glazings and the durability of this thread-based material is compatible with an industrial usage.

Abstract: A method for manufacturing a glass fiber having a polygonal cross section is provided. According to the method, a glass fiber having an orbicular cross section is manufactured by drawing molten glass supplied into a crucible heated at higher temperatures than a softening point of glass out of a nozzle having an orbicular cross section heated at lower temperatures than the heating temperature of the crucible and at higher temperatures than the softening point of glass. Then, the glass fiber is passed through a slit of a twin roller, having a predetermined shape, whereby glass fibers having a polygonal cross section are successively manufactured. The twin roller is heated at slightly higher temperatures than the softening point of the glass.

Abstract: A method of making an optical waveguide fiber with a fatigue resistant TiO.sub.2 -SiO.sub.2 outer cladding, and a substantially glass blank for drawing into such fiber, wherein a glass soot TiO.sub.2 -SiO.sub.2 outermost layer, with an initial TiO.sub.2 concentration greater than 10.5 wt. %, is deposited on a preform, and the preform is exposed to an atmosphere of chlorine and oxygen at a high temperature, and the resulting TiO.sub.2 concentration in the outermost layer of the TiO.sub.2 -SiO.sub.2 outer cladding of the substantially glass blank is less than the initial TiO.sub.2 concentration. In the glass blank form, the outermost layer includes a substantial volume percentage of crystalline phases and in the fiber form, the outermost layer includes inhomogeneities.

Abstract: A method of making an optical fiber having an oblong core comprising the steps of depositing layers of core glass particles and cladding glass particles on an enlarged mandrel, removing the mandrel to form a tubular porous preform, consolidating the porous preform to form a dense glass preform, evacuating the central hole of the dense glass preform while stretching that preform to collapse the central hole thereof and form a flattened rod, applying cladding material to the rod, and drawing the resultant composite to form an optical fiber. To facilitate the flat collapse of the central hole of the dense glass preform and to cause the core to have a large aspect ratio, the inside diameter-to-outside diameter ratio of the dense glass preform should be within the range of 0.3 to 0.9. For preferred core and cladding glasses, this ratio should be between 0.5 and 0.6. Also, the mandrel diameter should be at least 12 mm, and it is preferably between 25 mm and 50 mm.

Abstract: A method of forming an optical waveguide which includes the steps of forming on a substrate a waveguide layer including at least one host medium and one dopant medium, one of which is more volatile than the other; and heating the waveguide layer to selectively volatize the more volatile medium along a path, raising the index of refraction and creating a waveguide along the path.

Abstract: Low sodium hollow glass microspheres containing less than about 3 wt. % Na.sub.2 O are produced from aqueous precursors. The method comprisesa) forming an aqueous glass precursor solution or slurry by combining sources of cations contained in the glass, the solution or slurry comprising all of the glass cations in proportions substantially identical to those in the glass,b) forming the solution or slurry into droplets, andc) heating the droplets to form the microspheres.The precursor may also contain surfactants, blowing agents or other known expedients. Nonionic fluorocarbon surfactants are preferred.The droplets may be formed by spraying or any other known technique. The droplets may be spray dried prior to heating step c).

Abstract: The invention provides a method for producing an optical-fiber coupler with a preset branching ratio. The present invention relates to a method in which part of a plurality of optical fibers are made to closely contact with each other so as to form a coupler. The coupler is heated to thereby obtain a predetermined branching ratio; the flow rate of a gas to be supplied to a heat source is increased/decreased by a quantity proportional to a difference between the drawing speed and a preset drawing speed while predetermined tension is applied to the optical fibers.

Abstract: Fibers are drawn out by maintaining a temperature gradient between the interior and exterior walls of the peripheral band of a centrifuge. The peripheral band is made from a material having a thermal conductivity below 20 Wm.sup.-1 C.sup.-1 at 1000.degree. C. Application to the drawing out of fibers from glasses having a working range less than 100.degree. C. wide.

Abstract: In a device for performing measurements on at least partly transparent objects such as optical fibres a radiation beam is directed on the object. The radiation deflected by the object is imaged by means of a lens system (321, 322) on a radiation-sensitive detection system (330). As a result of refraction on interfaces between areas having a different refractive index (311, 312) in the object and between the object and the surroundings (315), dark or light bands corresponding to the projection of the interfaces are produced on the radiation-sensitive detection system (330). Thus measurements can be performed on the internal structure of the object.

Abstract: A process for manufacturing mirrors comprising notching the backside of a plate and etching it from one or both sides. The front side is plated and polished to a flat mirror-like-like surface. The plate is made from glass rods that have been fused together in a bundle and then heated and stretched. One of the glass rods, near the center, is being susceptible to etching while the others are not. Therefore, when the glass rod bundle is drawn out, they will neck-down and become very fine. When the center glass rod has been drawn down to, for example, about five mils in diameter, the neck of the bundle is harvested for the above plates, by slicing out wafers at an angle, e.g., 45.degree.. The etchants will attack the center glass rod, but not those that surround it, due to their chemical properties. The result is a very sharply formed aperture hole of any desired diameter.

Abstract: A process for manufacturing various series of plug-in light bulbs wherein a glass tube used in making a Wedge lamp having an increasing diameter toward one end, inserting two conductive wires and a button rod within this tube integrated with its bottom end by heating, pinching and attaching three filaments to the top portion of the button rod by heating and connecting to the conductive wires with a plurality of tungsten filaments to form a glow portion, inserting a bulb portion over the top end of the tube, then shaping a integral body by heating a lower portion of the tube rod slightly below the bottom end of the button rod, which is fused off by heating, the lower portion of the conductive wires being folded and stuck to the respective outside walls of the bottom end of the tube.

Abstract: A quartz glass crucible for use in a process for pulling a single crystal silicon and having an outer layer and an inner layer. The outer layer contains less than 0.3 ppm each of Na, K and Li and more thant 5 ppm of Al. The outer layer further contains bubbles to present an opaque appearance. The inner layer is made by melting powders of high purity non-crystalline synthetic silica and contains less then 200 ppm of OH group. There is also disclosed a method for producing the crucible.

Abstract: A preform tube (31) is caused to be collpased into a preform rod by causing a heat zone (54) provided by a torch assembly (50) to traverse the tube longitudinally in a plurality of passes. During this so-called collapse mode, a muffle tube (100) encloses that portion of the tube which extends through the torch assembly. Advantageously, the muffle tube projects a predetermined distance beyond one major face of the torch assembly. The torch assembly comprises annular semi-circular end plates and as annular semi-circular center portion having a plurality of exit ports through which gases are directed into engagement with the tube. The center portion is caused to be recessed between the end plates thereby causing the heat zone generated by the gases to be narrowed.

Abstract: A miniaturized sensor element is prepared using a capillary having first and second ends with a channel therebetween. One of the ends is closed while the other is open. Near the closed end, the capillary material which softens when heated, is heated and gas is supplied to the open end. This expands a chamber near the closed end which can be shaped and sized by moving the point of heating and varying the gas supply into the channel. The initially closed end is then opened and the channel inverted. The initially open end is then closed and again the capillary is heated and gas is supplied to form and shape a second chamber in the channel. After this, the closed end of the channel is again opened and both now open ends are smoothed to complete the capillary for use as part of a miniaturized sensor element.

Abstract: The present invention pertains to a process for manufacturing a road warning device for a divided driveway, expecially a process for manufacturing a warning device in different colors, in order to match the traffic signs, in such a way that one first presses a melting pulp of potash-glass to form a main body, then high pressure spray a tinfoil metal powder on the spherical surface of the warning device, trim the circumferences of the uncooled reflecting spheroid, remove the excess metal alloy powder, and finally spray a metal-oxide or metal-halide (e.g. silver oxide, plumbous oxide or gold sodium chloride etc.) either on the entire spherical or semispherical surface of the reflecting spheroid, in order to show different colors on the reflecting spheroid.