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, 1995
Filed:
Apr. 11, 1994
Tomoki Saito, Tokyo, JP;
Naoya Henmi, Tokyo, JP;
NEC Corporation, , JP;
Abstract
A signal light and a clock light which is generated by a clock light generator are propagated through a non-linear optical medium of, for instance, a silica based single mode optical fiber, from which the signal and clock lights and a four-wave mixing light are obtained. One light, for instance, the four-wave mixing light is extracted from the output lights of the non-linear optical medium, and a control signal which is dependent on a time-mean value in power of the extracted light is applied to a voltage controlled oscillator (VCO) for driving the clock light generator. Thus, a clock light which is locked in phase to the signal light is obtained. In case where the signal light comprises N time-division sequential lights (N=1, 2, 3, - - -), and a clock frequency of the clock light is 1/N of a clock frequency of the signal light, each one of the N time-division seaquential lights is shifted in phase or frequency by the non-linear optical medium, so that the phase or frequency shifted sequential light is switched to be demultiplexed by a switch device such as an optical coupler and a polarization beam splitter.