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:
Feb. 23, 2021
Filed:
Nov. 28, 2016
Fujikura Ltd., Tokyo, JP;
Takayuki Kitamura, Chiba, JP;
Fujikura Ltd., Tokyo, JP;
Abstract
An optical fiber production method includes: drawing an optical fiber from an optical fiber preform; and cooling the optical fiber. When in the cooling process, the optical fiber is passed through a plurality of annealing furnaces and Equation (1) is held. A time constant of relaxation of a structure of glass forming a core in the optical fiber is τ(T). A temperature of the optical fiber at a point in time when the optical fiber is delivered into an nth annealing furnace from an upstream side is T. A fictive temperature of glass forming the core at the point in time when the optical fiber is delivered is T. A fictive temperature of glass forming the core after a lapse of time Δt from the point in time when the optical fiber is delivered is T.20° C.<=()exp(−Δ/τ())<100° C.  (1)