Abstract:
Eine bekannte biegeunempfindliche optische Faser weist eine Kernzone mit einem Brechungsindex n K , einen die Kernzone umhüllende Mantelzone mit einem Brechungsindex n M , und eine die Mantelzone umgebende Ringzone aus einem mit Fluor dotierten Quarzglas mit einem Brechungsindex n F auf, wobei gilt n F M K . Hiervon ausgehend soll eine optische Faser zur Verfügung gestellt werden, die sich durch hohe Biegeunempfindlichkeit, gute Spleißbarkeit und Kompatibilität auszeichnet und ein Verfahren für eine kostengünstige Herstellung einer derartigen Faser angegeben werden. Hinsichtlich des Verfahrens wird diese Aufgabe erfindungsgemäß dadurch gelöst, dass das Quarzglas der Ringzone (21) in einem Plasma-Außenabscheideprozess erzeugt wird, indem auf einem Substratkörper (20) eine Ringzonenschicht aus dem mit Fluor dotierten Quarzglas mit einer Schichtdicke von mindestens 1 mm und einer Brechzahl n F
Abstract:
The invention starts from a known component of quartz glass for use in semiconductor manufacture, which component at least in a near-surface region shows a co-doping of a first dopant and of a second oxidic dopant, said second dopant containing one or more rare-earth metals in a concentration of 0.1-3% by wt. each (based on the total mass of SiO 2 and dopant). Starting from this, to provide a quartz glass component for use in semiconductor manufacture in an environment with etching action, which component is distinguished by both high purity and high resistance to dry etching and avoids known drawbacks caused by co-doping with aluminum oxide, it is suggested according to the invention that the first dopant should be nitrogen and that the mean content of metastable hydroxyl groups of the quartz glass is less than 30 wtppm.
Abstract:
Disclosed are high purity synthetic silica glass material having a high OH concentration homogeneity in a plane perpendicular to the optical axis, and process of making the same. The glass has high refractive index homogeneity. The glass can have high internal transmission of at least 99.65%/cm at 193 nm. The process does not require a post-sintering homogenization step. The controlling factors for high compositional homogeneity, thus high refractive index homogeneity, include high initial local soot density uniformity in the soot preform and slow sintering, notably isothermal treatment during consolidation.
Abstract:
Disclosed are a method for dehydration used in the optical fiber preform manufacturing process, and method and apparatus for manufacturing an optical fiber using the dehydration method. In the dehydration method, when the dehydrating gas is supplied into a tube during the optical fiber preform manufacturing process, dehydration reaction gas included in the dehydration gas is activated using a light source which emits light having a predetermined frequency capable of activating the dehydration reaction gas included in the dehydrating gas into atoms or ions. Then, the method uses the activated dehydration reaction gas generated as a result of the above process to eliminate moisture or hydroxyl group causing optical losses during the optical fiber preform manufacturing process.
Abstract:
Method for fabricating an optical fiber preform substantially without hydroxyl group in core includes forming clad layer having relatively low refractive index by depositing soot (SiO 2 , GeO 2 ) to inner surface of quartz tube; and forming core layer having relatively high refractive index on clad layer, which includes (a) a base core layer forming step composed of generating soot by heating inside of quartz tube to 1000 °C~1400 °C with introducing reaction gases (SiCl 4 GeCl 4 ) into quartz tube, accumulating soot on clad layer removing hydroxyl-groups (OH) and moisture from soot and tube by heating inside of quartz tube to 600 °C~1200 °C with introducing dehydration gases (He, Cl 2 ; O 2 ) into quartz tube, and sintering and vitrifying soot by heating quartz tube inside over 1700 °C with introducing dehydration gas (He, Cl 2 , O 2 ); and (b) a step of forming at least one additional core layer on base core layer by repeating the accumulating/dehydrating/sintering of the step (a) at least one time.
Abstract:
According to a known method for producing a tube consisting of doped quartz glass, the starting components are fed to a deposition burner, particles containing SiO2 and GeO2 are formed, and are deposited on a mandrel rotating about its longitudinal axis, forming a porous layer of soot. Based on said method, the aim of the invention is to ensure that the doping agent is distributed over the tube wall in a radially homogeneous manner. In order to achieve this, an outer compression area (3) having a higher density is generated in the outer area of the layer of soot, and surrounds an inner area (2) of the layer of soot, said inner area having a lower density. A tubular semifinished product consisting of porous quartz glass containing GeO2, which can be subjected to dehydration treatment without significantly changing the predefined distribution of doping agent over the tube wall, is characterised in that the area of the outer wall of the tube is provided with an outer compression area (3) having a higher density and surrounding an inner area (2) having a smaller density.