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:
May. 13, 2003
Filed:
Sep. 28, 2001
Sumitomo Electric Industries, Ltd., Osaka, JP;
Abstract
In a single mode optical fiber employed in an optical fiber coupler, letting r be the radial distance from the optical axis center, &Dgr;n(r) be the relative refractive index difference at the position r within a core portion with reference to the refractive index of a cladding portion placed about the core portion, &Dgr;n be the peak value of the relative refractive index difference &Dgr;n(r) at the position r , and a be the core radius, the relative refractive index difference &Dgr;n (r) satisfies the relationship of &Dgr;n(r)≦&Dgr;n [1−(r/a) ] in the range of r ≦r≦a; and the refractive index of the cladding portion gradually decreases outward in its radial direction.