Abstract: A method of producing a blank for the primary member of a glass mould in which an organic polymer, multifocal, ophthalmic lens is cast. A glass major element is formed that has a raised countersink zone on one surface, the remainder of the glass major element being thinner than the countersink zone, but of such thickness that it can form the far vision surface of a mould. A countersink is formed in the countersink zone and a segment element is formed and fused in the countersink. This forms a lens mould assembly which, when ground and polished to the predetermined far vision curvature and countersink size, produces a mould in which an organic lens may be cast.

Abstract: In a plate microlens of the invention, wherein gradient index lenses each having an optical axis along a normal to a surface of a transparent base and a refractive index profile gradually changing along a direction of the optical axis and a direction perpendicular thereto are formed integrally in the transparent base; a ratio d/a (where d is a thickness of the gradient index lens on the optical axis and 2a is a diameter of the gradient index lens on a surface of the transparent base) falls within a range of 0.46 to 0.78.

Abstract: A fiber optic coupler is formed by providing a glass tube having a longitudinal aperture extending therethrough. Protective coating is removed from a region of a first optical fiber intermediate the ends thereof. Protective coating is removed from an end region of at least one other optical fiber. The coated portion of the first fiber is threaded through the tube until the uncoated region thereof is near the tube end. The size of the aperture is insufficient for simultaneously receiving the coated portions of the first and second fibers in side-by-side relationship at the coated portion of both. The uncoated region of the second fiber is placed adjacent that of the first fiber, and both uncoated regions are simultaneously fed into the tube aperture.

Abstract: The present invention relates to a method for making a glass article having at least one surface which is essentially defect-free and is at least equivalent in smoothness to a polished surface. The method includes the steps of:(a) bringing into contact with each other a body of a glass which is relatively insoluble in an acid solution and a body of a glass consisting essentially, expressed in terms of cation percent on the oxide basis, of 70-85% B.sub.2 O.sub.3, 7-20% BaO, 0-10%, PbO, 0-12% R.sub.2 O, wherein R.sub.2 O consists of Li.sub.2 O+Na.sub.2 O+K.sub.2 O, 3-15% PbO+R.sub.2 O, the glass from its setting point to room temperature having a linear coefficient of thermal expansion within about 5.times.10.sup.-7 /.degree.C. of that of the relatively insoluble glass, a strain point within 10.degree. C.

Abstract: Paper having an unique twill weave wiremark produced using a dandy roll in which the outer screen bears has a twill weave; the dandy roll and the papermaking process are also disclosed.

Abstract: A process for the production of silica-bound zeolite granulates is disclosed, wherein zeolite to be formed into a granulate is mixed with silica sol. The process is carried out by adding aqueous alkali metal silicate to the silica sol immediately before the silica sol is mixed with the solid zeolite to be granulated. By the described process, granulates of various grain sizes can be obtained, and the resultant granulates can have a narrow grain size distribution.

Abstract: A biochemical analysis apparatus for applying a liquid sample onto a long test film, incubating the sample-applied film portion by an incubator, and measuring the degree of color formation at the sample-applied portion comprises a test film conveyor for continuously conveying at least the part of the long test film inside of the incubator so that a speed v [cm/min.] at which the part of the long test film inside of the incubator is conveyed is expressed as v=n.l. The incubator is constituted so that a length L [cm] of the incubator in the direction of conveyance of the long test film satisfies the condition of L.gtoreq.(nt+1).l, where l [cm] denotes the length of a portion of the long test film necessary for a single step of sample application, t [min.] denotes the incubation time, and n [number/min.] denotes the number of repetitions of sample application per unit time.

Abstract: A method of producing glass bodies having regions with different optical refraction, including a basic body and a coating layer which is sintered onto the basic body, covers the basic body at least partially and is made of glass, which as it is doped, has an index of refraction differing from that of the glass of the basic body. The starting material for producing the cladding on the basis of pulverulent ceramic material is deformed into a self-supporting, unsintered porous green body, is dried and submitted to a cleaning procedure in a heated gas phase. The coating layer to be bonded onto the basic body is melted into glass in a subsequent combined doping/sintering procedure in a gas phase containing the doping agent at a temperature in the range from 1150.degree. to 1500.degree. C. and is sintered onto the basic body.

Abstract: In a method for the production of sheets of mineral glass with high transmission in the visible spectral range and with low solar energy transmission, a coating is sputtered onto the sheet in a coating chamber by cathode sputtering with a target of an alloy of 65% tin and 35% nickel in an atmosphere with an oxygen content. The sheet and coating are then heated at 640.degree. C. and then bent in the heated state, thus producing an especially stable and electrically conductive combination.

Abstract: A preform tube (31) is caused to be collapsed 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 collapse mode, a muffle tube (100) encloses that portion of the tube which extends through the torch assembly. 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 an 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. The narrowing of the heat zone and the substantial confinement of the heat energy within the muffle tube cooperate with increased gas flow rates to cause the tube to be collapsed in a time period which is substantially less than that achieved by prior art methods.

Abstract: A buried wave guide device is produced by immersing a phosphate glass containing exchangeable ions in a molten salt. Ions are exchanged from the phosphate glass to give a wave guide whose refractive index increases sharply from a first surface to a maximum at a depth below the first surface then decreases gradually in the direction of the opposite surface.

Abstract: A method disclosure for making an economical fiber coupler including providing a glass tube having first and second end portions and a midregion, and a longitudinal aperture extending through it. Two suitably prepared glass optical fibers, each having a core and cladding, are disposed within the longitudinal aperture, the fibers extending beyond each end of the tube. The fibers are glued to each end portion. The midregion of the tube is evacuated, heated, collapsed about the fibers, and drawn to reduce the diameter of the resulting composite.

Abstract: Disclosed is a dry-etching apparatus composed of any of metal, silica, ceramic or combination thereof including a processing chamber in which substrates are placed and a diluted anhydrous hydrogen fluoride gas generator, the processing chamber being connected to the diluted anhydrous hydrogen fluoride gas generator through a pipe line of such metal as stainless steel or nickel. There is also provided according to the invention a dry-etching method with the dry-etching apparatus, a cooled anhydrous hydrogen fluoride gas source and a diluted anhydrous hydrogen gas generator used in the dry-etching apparatus and dry-etching method.

Abstract: A bushing balance controller controls the overall average temperature of a multiple segment glass fiber forming bushing and the temperature of each individual bushing segment. Current shunting loops divert current away from each bushing segment as required to provide the proper bushing segment temperature profile as well as the desired average bushing temperature.

Abstract: A fluoride glass is prepared by depositing a solid including a metal fluoride on a heated substrate, from a gaseous mixture of a nonmetallo-organic compound, carbon dioxide, and a source of carbonyl fluoride. The nonmetallo-organic compound contains the metallic cation of the metal fluoride bonded to an organic species through an electronegative element such as oxygen, but not directly to a carbon atom. The carbon dioxide, or optionally another species reactive with carbon to produce a gas, oxidizes solid carbon and other reduction products of the organic compound that could otherwise be present in the deposited metal fluoride to impair optical properties of the fluoride glass. The carbonyl fluoride, supplied by the gas itself or by reactants that produce the gas, reacts with the nonmetallo-organic compound without producing water, which would otherwise degrade the glass purity.

Abstract: Reproducible doped optical fiber preforms having a predetermined dopant concentration level are fabricated by inserting a doped filament into a completed preform prior to consolidation and final collapse so that the filament and dopant materials are centrally located in the core region upon formation of the preform. Doped fiber is drawn from the doped preform using standard fiber drawing techniques.

Abstract: In a glass manufacturing method by means of a float bath for manufacturing a sheet glass by floating a glass ribbon on molten metal, a plate made of heat resistant and highly heat conductive carbon fiber carbon composite material is disposed between the floated glass ribbon and the ceiling portion of the float bath, so that obstacles can be prevented from dropping on the glass ribbon.

Abstract: Improved fluoride glass optical fibers are produced by a process introducing several improvements in the production of fluoride glass preforms and the drawing of fibers therefrom. Reduced bubble formation and crystallization are obtained by vertically spinning a fluoride glass melt within a glass cladding tube at a high rotational speed, or alternatively, pouring a flouride glass core melt into a cladding tube while slowly raising the mold from an inclined position to a vertical position, or alternatively, introducing a core tube inside a cladding tube. The production of fibers is enhanced if at least one production phase, i.e., preform formation or fiber drawing, is conducted in an atmosphere containing reactive gases that scavenge molecules that could otherwise react with, hydrolyze and oxidize the fluoride glass. The disclosure also describes several devices uniquely useful in the process of the present invention.

Abstract: An optical fiberglass preform having fluorine selectively added to its cladding is produced by:depositing soot of quartz glass on a pipe from starting member by using burners for synthesizing glass soot to form a porous glass preform consisting of a core porous glass body a peripheral portion of which has a larger bulk density than the other portion and a cladding porous glass body,heating said porous glass preform in a dehydration atmosphere while supplying dehydration gas through the pipe form starting member andheating and vitrifying the dehydrated porous glass preform in an atmosphere containing a fluorine-containing compound.

Abstract: A method for producing a glass preform for use in the fabrication of an optical fiber, including the steps of forming a glass soot preform from a glass-forming raw material and heating the soot preform to vitrify it, the soot preform being heated in an atmosphere comprising SiF.sub.4 under pressure higher than 1 atm. for a period of time sufficient to add fluorine, between the formation of the soot preform and the vitrification of it, fluorine being added at a high rate and in a large amount.