The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 17, 1989
Filed:
Apr. 25, 1988
Kiyoshi Yokokawa, Gunma, JP;
Kazuo Koya, Gunma, JP;
Shin-Etsu Chemical Co., Ltd., Tokyo, JP;
Abstract
In place of the conventional rod-in-tube method, a novel method is proposed for the preparation of a high-quality base material of quartz glass for optical fibers according to which a glassy rod composed of the core portion of a larger refractive index and the first cladding layer of a smaller refractive index is first prepared by silica soot deposition by the flame hydrolysis of a gaseous silicon compound followed by dehydration and vitrification, and then the glassy rod is covered with a layer of further silica soot deposition which is subsequently converted to the second cladding layer by vitrification. The inventive base material for optical fibers is excellent in the geometry relative to the diameter of the core portion and thickness of the cladding layer as well as concentricity of the core and the cladding.