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:
Dec. 12, 2000
Filed:
Jul. 20, 1999
Hiroyuki Hoshino, Hitachi-shi, JP;
Other;
Abstract
Disclosed is a method for producing a chirped in-fiber Bragg grating, in which an interval between gratings varies continuously depending on a location of the gratings observed along an optical fiber, comprising a first step of winding the optical fiber in a spiral groove formed around a conical bobbin which is shaped in a frustum of a right circular cone having a predetermined vertex angle and a height between predetermined first and second diameters, and a second step of irradiating the optical fiber wound on the conical bobbin with ultraviolet rays at every crossing of the optical fiber with a predetermined number of uniformly distributed generating lines of the conical bobbin, each extending radially on the surface of the conical bobbin from an imaginary vertex thereof, for modifying the refractive index of a core of the optical fiber to form the grating at the every crossing.