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:
Jun. 04, 2002
Filed:
Nov. 13, 1995
Mikiya Suzuki, Tokyo, JP;
Shigeru Shikii, Tokyo, JP;
Yukihiro Ozeki, Tokyo, JP;
Shusei Aoki, Tokyo, JP;
Oki Electric Industry Co., Ltd., Tokyo, JP;
Abstract
An EDFA is comprised of a pre-amp and a post-amp which are connected in series, a photocoupler a long wave pass filter (LWPF) and an LWPF controller The photocoupler is connected to an input-stage of the EDFA and enters the light signal in the LWPF controller The LWPF is located between the pre-amp and the post-amp and its cutoff wavelength is adjustable. A short-wavelength-part of the light signal which is amplified by the pre-amp is cut off by the LWPF The LWPF controller detects an input signal power of the input light signal and adjusts the cutoff wavelength of the LWPF based on the detected input signal power. Gain of light signals which are output from the post-amp are equalized ranging the extensive input signal power and covering wide signal-wavelength bands.