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. 31, 1981
Filed:
Mar. 02, 1979
Yasuo Tsukuda, Ome, JP;
Katsuyuki Imoto, Sayama, JP;
Kenzo Susa, Tokyo, JP;
Iwao Matsuyama, Sagamihara, JP;
Tsuneo Suganuma, Tokorozawa, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A method for producing an optical fiber preform comprising the steps of blowing, through at least one nozzle, gaseous material producing glass material soot by a CVD reaction to permit the glass material soot to be deposited on a target to produce a soot rod which grows in size, and heating and rendering transparent the soot rod produced in the first step, wherein a pipe is arranged substantially concentrically with the glass material soot so as to permit gas to flow through a clearance between the deposited glass material soot and the inner wall surface of the pipe in a direction in which the soot rod grows in size. The method makes it possible to prevent the outer peripheral portion of the soot rod from becoming porous and to satisfactorily control the diameter of the soot rod.