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. 07, 2001
Filed:
Feb. 26, 1999
Yukio Michishita, Tokyo, JP;
Satoshi Ishii, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
A signal conversion device comprises a light source for emitting continuous wave (CW) light at a predetermined wavelength &lgr;, an optical element having a saturable absorption function, and a wavelength demultiplexing circuit for separating signal light at a desired wavelength from signal light outputted from the optical element. A threshold value for optical transmission and absorption of the optical element having the saturable absorption area is set to a level such that applied signal light at a wavelength &lgr;s and the CW light outputted from the light source are absorbed at a light intensity level of either of the two lights, and are transmitted at a light intensity level of a total of the two lights.