Abstract:
Die Erfindung beschreibt ein Verfahren zur Herstellung von Quarzglas, das zusätzlich zu einer Dotierung mit Seltenen Erden und/oder Übergangsmetallen die Fluorierung des Quarzglases umfasst. Durch das beschriebene Verfahren lässt sich ein Ausdiffundieren er Dotanden während der Fluorierung verhindern. Weiterhin betrifft die Erfindung das nach dem erfindungsgemäßen Verfahren erhältliche Quarzglas sowie dessen Verwendung als laseraktives Quarzglas, zur Erzeugung von lichtführenden Strukturen und für den Einsatz in optischen Anwendungen.
Abstract:
Process for producing a sintered granular material containing silicon dioxide and having a BET surface area of less than 1 m 2 g and a proportion of impurities of less than 50 ppm, in which a mixture which contains silicon dioxide powder and a metal compound is intensively mixed in an atmosphere having a relative atmospheric humidity of from 1.0 to 100% at temperatures of from 0 to 50°C by means of a dispersing apparatus, the crumbly mass is divided into pieces, subsequently dried, purified 'and sintered. The moisture content of the silicon dioxide powder and/or the atmospheric humidity are/is at least sufficient to hydrolyse the metal compound completely.
Abstract:
Die vorliegende Erfindung betrifft ein Verfahren zur Herstellung von mit Fluor dotiertem Quarzglas. Weiterhin betrifft die vorliegende Erfindung nach dem vorgestellten Verfahren erhältliches mit Fluor dotiertes Quarzglas sowie dessen Verwendung im Bereich der Optik, beispielsweise als optisches Bauteil.
Abstract:
This disclosure is directed to a silica-titania-niobia glass and to a method for making the glass. The composition of the silica-titania-niobia (SiO 2 -TiO 2 -Nb 2 O 5 ) glass, determined as the oxides, is Nb 2 O 5 in an amount in the range of 0.005 wt.% to 1.2 wt.% TiO 2 , in an amount in the range of 5 wt.% to 10 wt.%, and the remainder of glass is SiO 2 . In the method, the STN glass precursor is consolidated into a glass by heating to a temperature of 1600°C to 1700°C in flowing helium for 6 hours to 10 hours. When this temperature is reached, the helium flow can be replaced by argon for the remainder of the time. Subsequently the glass is cooled to approximately 1050°C, and then from 1050°C to 700°C followed by turning off the furnace and cooling the glass to room temperature at the natural cooling rate of the furnace.
Abstract:
A method for controlling the refractive index achieved using a fluorine dopant gas, wherein CF4 is employed as the dopant gas, and the soot preform (12) is doped using the CF4 for a time and temperature sufficient to result in a decrease in fluorine dopant nearest the surface which is in contact with the CF4 gas. Preform (12) is mounted on handle (11) which is fused to handle (14) and the assembly (20) is heated in a furnace muffle (15). The CF4 flows through furnace muffle (15), as indicated by arrows (17), and preferably contains a diluent gas such as helium. An optional centerflow gas (16) may be flowed through the centerline hole (18) in several embodiments, which consists of helium. The end of the porous preform (12) may optionally include a capillary tube (19) to prevent the muffle gases (17) from entering the preform.
Abstract:
A ultralow-loss silica glass characterized by comprising a high-purity silica glass and at least one network-modifying oxide in an amount of 1 to 500 ppm (by weight). The oxide is considered to suitably relax the tetrahedral network structure of silica so as to lower the Rayleigh scattering loss. Examples of the network modifying oxides usable herein include Na>2 2 2
Abstract:
Doped quartz glass is produced by fusing a mixture of quartz powder with a concentrate. The concentrate consists of the oxides of alkaline earth metals and/or alkali metals. (dopants) By adding a small quantity of dopants a doped quartz glass can be obtained having a viscosity behaviour corresponding to that of Vycor glass. Still softer glasses can be obtained by the addition of some more dopants.