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:
Aug. 11, 2009
Filed:
Apr. 27, 2007
Dai Inoue, Gunma, JP;
Hiroshi Oyamada, Gunma, JP;
Yuichi Morishita, Kawasaki, JP;
Shin-Etsu Chemical Co., Ltd., Tokyo, JP;
Abstract
An optical fiber includes a clad portion and a core portion surrounded by the clad portion. Here, the clad portion is formed by substantially pure quartz, and the core portion has a higher refractive index than the clad portion. The optical fiber is characterized in that a relative refractive index difference of a center of the core portion falls within a range from 0.15% to 0.30%, and a maximum relative refractive index difference of the core portion falls within a range from 0.4% to 0.6%. Here, it is preferable that an average relative refractive index difference of the core portion falls within a range from 0.30% to 0.40%. Here, a mode field diameter of the optical fiber falls within a range from 8.6 μm to 9.5 μm at 1310 nm, and a cable cutoff wavelength of the optical fiber is equal to or lower than 1260 nm. Note that, after the optical fiber is subjected to hydrogen aging, a loss of the optical fiber is preferably equal to or lower than 0.4 dB/km at 1383 nm.