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. 24, 2005
Filed:
Apr. 25, 2002
Junji Yamauchi, Koganei, JP;
Michiya Masuda, Yokohama, JP;
Shigeru Kawaguchi, Yokohama, JP;
Hisamatsu Nakano, Kodaira, JP;
Yuichi Yamamoto, Koganei, JP;
Ryouichi Tazawa, Yokohama, JP;
Junji Yamauchi, Koganei, JP;
Michiya Masuda, Yokohama, JP;
Shigeru Kawaguchi, Yokohama, JP;
Hisamatsu Nakano, Kodaira, JP;
Yuichi Yamamoto, Koganei, JP;
Ryouichi Tazawa, Yokohama, JP;
NHK Spring Co., Ltd., Yokohama, JP;
Abstract
An optical multi-demultiplexer of the present invention comprises an input waveguide to which wavelength division multiple signals are applied, a plurality of output waveguides for demultiplexing and outputting the wavelength division multiple signals, an arrayed waveguide including a plurality of channel waveguides having different waveguide lengths, an input slab waveguide, and an output slab waveguide. The input slab waveguide is provided between the input waveguide and the arrayed waveguide. The output slab waveguide is provided between the arrayed waveguide and the output waveguides. The input slab waveguide is formed with tapered island regions having a refractive index lower than that of the core layer of the slab waveguide. The island regions are situated in positions opposite the channel waveguides of the arrayed waveguide.