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:
Feb. 24, 2009
Filed:
Aug. 02, 2007
Applicants:
Hiroyuki Tsuda, Yokohama, JP;
Hiroshi Ishikawa, Tokyo, JP;
Hisato Uetsuka, Tokyo, JP;
Inventors:
Assignees:
KEIO University, Tokyo, JP;
Hitachi Cable, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G02B 6/26 (2006.01);
U.S. Cl.
CPC ...
Abstract
A diffraction grating of the present invention includes a first block () and a second block (). The first block () is made up of a plurality of input waveguides (), a slab waveguide (), a delay waveguide array () and narrow grooves (): each of which being filled with resin. The second block () is made up of a plurality of input waveguides (), a slab waveguide () and a plurality of output waveguides (). Since a circuit is cut off at the ends of the arrayed waveguides, a relative phase can easily be measured. The resin has undergone a refractive-index adjustment and compensates a phase error.