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. 28, 2014
Filed:
May. 01, 2012
Naritoshi Yamada, Sakura, JP;
Shunichirou Hirafune, Sakura, JP;
Naritoshi Yamada, Sakura, JP;
Shunichirou Hirafune, Sakura, JP;
Fujikura Ltd., Tokyo, JP;
Abstract
A method of producing optical fiber preform includes: forming a deposited layer by depositing glass particles on a periphery of a target element in a deposition mode while burning a mixed gas containing a glass source material gas, a flaming gas, and a supporting gas by use of a flaming burner; maintaining a state where the supporting gas flows at a flow velocity greater than or equal to a flow velocity at which a nozzle end of the supporting gas discharge nozzles does not glow while maintaining a pilot burner by allowing the flaming gas to flow to the seal gas discharge nozzle after a seal gas is replaced with the flaming gas in a case where a mode is changed from the deposition mode to a non-deposition mode; and replacing the flaming gas flowing to the flaming gas port with a purge gas.