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:
Apr. 15, 2003
Filed:
Aug. 08, 2000
Hisato Uetsuka, Hitachi, JP;
Masahiro Okawa, Hitachi, JP;
Koichi Maru, Hitachi, JP;
Hideki Nounen, Hitachi, JP;
Tatsuo Teraoka, Hitachi, JP;
Hitachi Cable, Ltd., Tokyo, JP;
Abstract
An optical wavelength multiplexer/demultiplexer includes a substrate, an input channel waveguide, an input slab waveguide, a channel waveguide array which has a plurality of channel waveguides, each channel waveguide differing in length from its neighboring waveguide by predetermined amount, an output slab waveguide, and a plurality of output channel waveguides. The input slab waveguide or output slab waveguide have a temperature compensation material, in its light path, having an opposite sign of diffraction temperature change to the plurality of channel wave guides, or a material capable of canceling a change in the in-phase plane of light having each wavelength which occurs in a vicinity of the channel waveguide array and the slab waveguide, or a waveguide for band width adjustment on which a waveguide to adjust band width of wavelength multiplexing light is provided.