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:
Mar. 09, 1982
Filed:
Jul. 21, 1980
Applicant:
Inventors:
Takao Edahiro, Mito, JP;
Gotaro Tanaka, Yokohama, JP;
Toru Kuwahara, Yokohama, JP;
Michihisa Kyoto, Yokohama, JP;
Assignees:
Nippon Telegraph & Telephone Public Corp., Tokyo, JP;
Sumitomo Electric Industries, Osaka, JP;
Primary Examiner:
Int. Cl.
CPC ...
C03B / ;
U.S. Cl.
CPC ...
65 182 ; 65-312 ; 65 13 ; 65 32 ;
Abstract
A process for producing an optical fiber preform which comprises forming a particulate glass rod in which the dopant concentration gradually increases toward the center of its cross section, and gradually heating the rod starting at a temperature below the minimum collapsing point of the fine glass particles in the center of the rod in such a manner that the softening of the rod proceeds from the center outward, to thereby produce a transparent glass rod.