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:
Jul. 17, 2012
Filed:
Aug. 21, 2008
Brent E. Little, Glen Head, NY (US);
Wei Chen, Ellicott City, MD (US);
Brent E. Little, Glen Head, NY (US);
Wei Chen, Ellicott City, MD (US);
Infinera Corporation, Sunnyvale, CA (US);
Abstract
Consistent with the present disclosure a compact, integrated tunable filter is provided that can adjust the power levels of optical signals output from an optical amplifier, for example, so that the amplifier has a uniform spectral gain. The tunable optical filter includes a planar lightwave circuit (PLC) having cascaded Mach-Zehnder interferometers, each of which having corresponding differential optical delays. At least one of the differential optical delays is different than the rest. Alternatively, the differential optical delays are different from one another. Each of the Mach-Zehnder interferometers is connected to one another by a tunable optical coupler. Such a filter has an improved frequency response in that the number of shapes that the transmission spectrum may have is increased. Accordingly, the optical filter may be more finely tuned to more effectively flatten, for example, the output of the optical amplifier. In addition, since the tunable optical filter is realized with a planar lightwave circuit (PLC) component, manufacturing costs can be reduced, and a more compact device can be obtained.