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:
Nov. 18, 2014
Filed:
Oct. 07, 2010
Nobuaki Hatori, Kanagawa, JP;
Tsuyoshi Yamamoto, Kawasaki, JP;
Yasuhiko Arakawa, Kanagawa, JP;
Fujitsu Limited, Kawasaki, JP;
University of Tokyo, Tokyo, JP;
Abstract
An active layer () is formed over a semiconductor substrate having a pair of facets (A,B) mutually facing opposite directions. An upper cladding layer () is formed on the active layer, having a refractive index lower than that of the active layer. A diffraction grating () is disposed in the upper cladding layer on both sides of a distributed feedback region in a waveguide region (), the waveguide region extending from one facet to the other of the semiconductor substrate. End regions (B) are defined at both ends of the waveguide region and the distributed feedback region (A) is disposed between the end regions. Low refractive index regions () are disposed in the upper cladding layer on both sides of each of the end regions of the waveguide region, the low refractive index regions having a refractive index lower than that of the upper cladding layer.