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:
May. 06, 2003
Filed:
Aug. 03, 2001
Applicant:
Inventors:
Assignee:
Sumitomo Electric Industries, Ltd., Osaka, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02B 6/26 ; G02B 6/42 ;
U.S. Cl.
CPC ...
G02B 6/26 ; G02B 6/42 ;
Abstract
Three Mach-Zehnder interferometers to are connected in a series between an optical input terminal and an optical output terminal in an optical filter. Each interferometer is composed of two optical paths optical coupled at both ends by optical couplers. Only one interferometer has same optical path lengths between optical couplers. Heaters are disposed on each optical paths to allow the slope of transmission loss to change through the adjustment of the phase shift between those respective optical paths.