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. 10, 2000
Filed:
Sep. 29, 1997
Olivier Gautheron, Montigny le Bretonneux, FR;
Vincent Letellier, Paris, FR;
Alcatel, Paris, FR;
Abstract
A drop/insert apparatus for dropping/inserting channels on a both-way multi-channel optical link includes a 'line' optical fiber serving to convey optical signals in two opposite transmission directions, over at least two channels having distinct wavelengths per transmission direction. The apparatus comprises: two main circulators inserted in said line fiber [two of the ports of each of them are connected to said line fiber, and their third ports are connected respectively to a first auxiliary optical fiber and to a second auxiliary optical fiber], each main circulator causing the optical signals to rotate in a rotation direction such that the signals propagating along said line fiber in one of the transmission directions remain in the line fiber; and, two auxiliary circulators inserted respectively in said first auxiliary fiber and in said second auxiliary fiber, each of said auxiliary circulators causing the optical signals to rotate in a direction opposite to that of the main circulator to which it is connected directly by one of said auxiliary fibers. At least one diffraction grating, having a reflection wavelength corresponding to the wavelength of a channel to be dropped in the go direction, is inserted in the line fiber between the main circulators, and at least one diffraction grating, having a reflection wavelength corresponding to the wavelength of a channel to be dropped in the return direction, is inserted in the by-pass fiber between the auxiliary circulators.