Method of producing synthetic quartz glass, apparatus for the practice of the method, and use of the synthetic quartz glass
Patent 4162908 Issued on July 31, 1979. Estimated Expiration Date: 
February 3, 1998. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
February 3, 1998. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 3275408 3659915 3778132 3843229 Method of making fluorine out-diffused optical device Patent #: 3981707 InventorsAssigneeApplicationNo. 05/874965 filed on 02/03/1978US Classes:65/60.53, From inorganic oxides or hydroxides385/123, OPTICAL FIBER WAVEGUIDE WITH CLADDING385/141, HAVING PARTICULAR OPTICAL CHARACTERISTIC MODIFYING CHEMICAL COMPOSITION427/167, Silicon compound coating (e.g., quartz, etc.)427/452, Silicon containing coating65/391, Plasma utilized65/397, Fluorine doping65/426Drying, dehydration, OH removal or preventionExaminersPrimary: Schor, Kenneth M.Attorney, Agent or FirmInternational ClassesC03B 37/018 (20060101)C03C 3/06 (20060101) C03B 37/014 (20060101) Foreign Application Priority Data1975-08-16 DEAbstractAn improvement in a method for producing a synthetic hydroxyl ion-free quartz glass wherein a hydrogen free silicon compound is heated in a hydrogen-free gas stream while the gas stream is passed through an induction coupled plasma burner, the gas stream containing elemental and/or bound oxygen and the oxidation product is deposited on a refractory support as a vitreous mass, the improvement lying in including in the gas stream a gaseous hydrogen-free, thermally decomposable compound which yields fluorine in an amount of at least 500 gms. per kilogram of silica to be produced; an apparatus for producing a synthetic OH ion-free quartz glass comprising an induction coupled plasma burner which burner has disposed thereabout 3 concentric quartz glass tubes disposed in stepped configuration of which the outermost tube is the longest and the innermost tube is the shortest. The apparatus includes means for passing through the innermost tube a hydrogen-free gas stream containing elemental oxygen and/or bound oxygen together with a gaseous hydrogen free thermally decomposable compound which yields fluorine. The apparatus further contains means for passing a separating gas such as oxygen through the space defined by the innermost tube and the middle tube and the middle tube and the outermost tube. | |
