Abstract: A single-mode optical waveguide is constructed in a manner such that the core thereof is subjected to a stress-induced birefringence. A coating of core glass soot is deposited on the surface of a cylindrical mandrel, and a coating of inner cladding glass soot is deposited on the core glass soot. The mandrel is removed and the resultant porous preform is consolidated to form a hollow dense glass preform. The preform aperture is closed at both ends. Diametrically opposed slabs are removed from the inner cladding region of the consolidated preform. The resultant article is evacuated, heated and stretched to close the aperture and form a preform foreproduct having two opposed rounded sides and two opposed flattened sides. The foreproduct is coated with a layer of outer cladding glass soot having a thermal coefficient of expansion which differs from that of the inner cladding glass by at least 1.times.10.sup.-7 /.degree.C.

Abstract: A lightguide furnace (10) includes a tube (32) at its base. The tube (32) has at least one opening (34) therethrough, in communication with, but substantially misaligned relative to, a corresponding opening (40) through a sleeve (36) coaxially aligned with, and rotatable about the tube (32). The substantial misalignment between each sleeve opening (40) and each tube opening (34) causes the cooling gas entering the furnace to be directed at least partially around the lightguide fiber (14). The cooling gas passes upwardly along the walls of the furnace away from the lightguide fiber (14) to reduce the likelihood of contamination thereof by particulates in the cooling gas. By rotating the sleeve (36) relative to the tube (32), the degree of misalignment of the sleeve openings (40) relative to the tube openings (34) can be adjusted to control the lightguide fiber cooling to regulate the tension.

Abstract: The invention relates to a glass lathe for producing preforms which may be drawn into energy transmitting fibers. The apparatus includes a head stock and a tail stock for rotatably holding a starter tube and the preform as it is built from the starter tube. The tail stock is movable along the lathe bed with respect to the head stock so that a preform may be drawn down to approximately the diameter of the starter tube. A carriage is provided on the lathe bed which carries at least one burner for melting a particulate quartz feed and depositing it onto the rotating surface of the starter tube. A slide member mounted on the carriage supports a container for catching particulate quartz which does not adhere to the tube and a coolant reservoir adapted to produce a fountain for contacting and cooling the tube downstream of the burner.

Abstract: A color cathode ray tube having a phosphor pattern on the mask and a window in the tube wall to allow external detection of the phosphor emissions, also incorporates arc limiting features including a high resistance coating in the neck region of the tube and a getter designed and placed to direct getter flash away from the neck, window and mask areas. Such a tube is useful, for example, for high resolution color displays having an automatic convergence feature.

Abstract: A porous glass optical waveguide preform is formed by depositing a coating of glass particulate material on the lateral surface of a core which may be a porous glass body continuously produced by the axial deposition of glass particles. The core rotates and moves longitudinally in one direction with respect to two flame hydrolysis burners which emit streams of glass particles having different compositions. In addition, the two burners reciprocatingly move with respect to a portion of the length of the core. The speed of each burner varies as it traverses along its path of reciprocating motion. The thickness of the layer produced by a burner at a given point is inversely related to the speed of the burner as it passes that point. The layers formed by the completion of a single traverse by both burners combine to form a conically-shaped layer, the composition of which varies from the base toward the apex thereof.

Abstract: A four axis adjustment mechanism is disclosed for adjusting the orientation of the deflector of the delivery system of a rotating table type of glassware forming machine. The orientation of the deflector is adjustable as it oscillates along a predetermined arcuate path relative to its deflector axis in order to properly position the deflector over a corresponding continuously moving blank mold. These adjustments are termed radial, radial tilt, peripheral and peripheral tilt.

Abstract: A single-mode optical waveguide is constructed in a manner such that the core thereof is subjected to a stress-induced birefringence. A single-mode optical fiber preform is formed by a CVD process. A pair of longitudinally extending holes is formed on opposite sides of the core, spaced slighty therefrom. A stress rod having a TCE different from that of the cladding portion of the preform is inserted into each hole. The space between the holes and the rods is evacuated. The resultant composite structure is drawn into an optical fiber. A similar method is used to form a fiber having multiple light conducting cores, this method differing in that the rods which are inserted into the holes are formed of a glass having a refractive index greater than that of the cladding portion of the preform.

Abstract: A single mode optical fiber manufacturing process can be monitored and/or controlled determining the mode field radius and/or the cut-off wavelength of fiber produced by the process, comparing these measured fiber parameter values to predetermined target values, and setting a process step in accordance with the result of the comparison. Both fiber parameters are determined by a procedure comprising measuring, as a function of angle, the far-field power emitted by a test fiber segment, and determining the parameters of a Gaussian function G(.theta.), typically by maximizing the value of an overlap integral.

Abstract: A glass melting apparatus is provided with a melting tank, a refining tank and a working tank wherein the melting tank is operatively connected to the refining tank by a temperature control connecting pipe for intermittently supplying molten glass from the melting tank to the refining tank in dependence upon the level of molten glass within the refining tank. The melting tank may be comprised of a single tank which is considerably larger than the refining tank and the working tank or may be comprised of a plurality of individual, movable tanks each of which may be brought into operative association with the refining tank for melting raw material in the melting tank, the molten glass being supplied to the refining tank and continuously treated and supplied to the working tank.

Abstract: A plurality of open trenches or sluices is suspended from the underside of the forming floor of a glass factory to register with the lower, discharge ends of hot gob reject or cullet chutes. Each sluice is suspended with one end higher than the other, and with their lower, discharge ends communicating with one end of a large quenching tank, which is mounted on the floor beneath the forming floor. The tank contains a supply of cooling water, which is continuously pumped to the upper ends of the sluices, so that as hot gobs drop from the chutes into the sluices they are immersed in the cooling water and travel by gravity with the cooling water downwardly in the sluices to the quenching tank. A conveyor in the tank transports the cullet through the cooling water to a discharge point adjacent the opposite end of the tank. The bottom of each sluice is generally V-shaped in configuration so that frictional engagement of the hot cullet with opposite sides of a sluice is minimized.

Abstract: Processes and alkaline cleaning compositions for cleaning aluminum containers to prevent off-flavor and off-taste in liquid comestible products with which the containers are filled. The processes involve the use of an aqueous alkaline cleaning solution having the following compositions:______________________________________ Ingredient Quantity, g/l ______________________________________ 1. Alkali metal or ammonium carbonate 0.1-0.9 2. Alkali metal or ammonium tripoly- 0.6-7.6 phosphate (anhydrous) 3. Alkali metal or ammonium tetraborate 0.5-6.3 (pentahydrate) 4. Alkali metal or ammonium metasilicate 0.1-0.8 (anhydrous) 5. Tri(alkali metal or ammonium)phosphate 0.4-5.4 (anhydrous) 6. Alkali metal or ammonium gluconate or 0.1-1.3 glucoheptonate 7. Surfactant 0.02-0.

Abstract: A tunnel furnace composed of modular sections, each modular section comprising horizontal and mutually parallel openings occupying the width of a heat treatment enclosure, the openings being beneath the top of a conveyor and adjacent each other in a direction parallel to the direction of travel of the conveyor with each opening extending perpendicular to the direction of travel, such that each opening gives out a sheet of ascending gas, a collecting slot formed in an upper wall of the heat treatment enclosure extending horizontally, mutually parallel, perpendicular to the direction of travel of the conveyor and extending the width of the enclosure, such that the slot collects the sheet of ascending gas, temperature adjusting devices for maintaining the temperature of the collected gas for the module, a circulating fan for accepting the collected gas and circulating the gas via a gas circulation path to the openings after passing through the temperature adjusting devices and a regulating device for controlling

Abstract: A high temperature induction furnace (10) for drawing lightguide fiber (52) from a silica preform (44) has an axially located tubular zirconium dioxide susceptor (34) therein. Prior to use, at least a portion of the inside surface of the susceptor (34) is coated with a vapor deposited silica "soot" (54). The silica soot (54) is then consolidated at an elevated temperature. Surprisingly, such a technique substantially eliminates migration of zirconium dioxide particles from the susceptor (34) to the preform (44) and/or the fiber 52 without deleteriously affecting the susceptor (34) and/or the operation of the furnace (10).

Abstract: The present invention relates to a technique for producing polarization-preserving and single polarization optical fibers. As disclosed, high birefringence is introduced into the preform by deforming the fiber preform such that a cladding layer becomes flat and highly conformable, while the core remains hard and substantially round. In particular, a cladding layer with a relatively low melting point is utilized such that when the preform is heated the cladding becomes liquified while the core remains solid. The preform may then be deformed so that the cladding layer is substantially flattened. Standard drawing techniques may then be utilized to form polarization-preserving fibers and single polarization fibers from the preform.

Abstract: There is disclosed a system for delivering gobs to a plural section glass forming machine in which an oscillating scoop distributes the gobs not only to the machine sections but also, on command to the servo motor drive for the scoop, to a delivery trough extending to a cullet chute. The chute may be behind the machine or in front. When it is desired to reject gobs from a section, the command is given to the motor control, which will index the scoop to the reject position instead of to the section so that it may be taken out of service.

Abstract: A method for reducing the amount of particles which become airborne during either or both the dismantling and moving of structures wherein a foam is sprayed on the structures prior to either or both the dismantling and moving of such structures.

Abstract: A process for manufacturing a preform from which is drawn an optical fiber, the core of which comprises layers of different glass composition. In one embodiment, the known CVD process for making preforms is modified by halting rotation of the substrate tube while the tube is asymmetrically heated by a source that traverses the length of the tube. A vapor mixture flowing through the tube reacts only near that region of the inner surface of the tube that is being heated. This forms a longitudinal strip of glass particles. The flow of reactants stops, the tube is rotated, and it is traversed by heating means which heats the tube to a temperature sufficiently high to fuse the glass particles and forming a longitudinal strip of glassy material.

Abstract: An improved blank cylinder mechanism for a glassware making machine which utilizes shims between the bottom plate and support in conjunction with the cam track to adjust the angular position of the cylinder in down position. Also, the blank cylinder mechanism uses a double tapered slot in the piston rod to provide cushioning.

Abstract: An improved means for incorporating an electron gun and stem assembly into the neck of a cathode ray tube wherein the stem is engaged with a metal collar while providing a groove therebetween, a thermally insulating fusible adhesive having an initial melting point lower than that of the stem is introduced into the groove, an end portion of the neck of the cathode ray tube is inserted into the groove, and the entire assembly is bonded together by means of fusion of the thermally insulating adhesive.

Abstract: A method of forming optical fibers with minimal contamination from ambient air is disclosed. In the inventive method a gas stream is introduced into a rotating structure by means of a rotating seal. The rotating seal comprises a rotating member seated within a stationary member. Counterflowing gases are flowed through the clearance region between the rotating and stationary members to prevent seepage of ambient air into the gas stream.