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. 25, 2004
Filed:
Sep. 18, 2002
Applicant:
Inventor:
Tohru Takiguchi, Tokyo, JP;
Assignee:
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01S 5/00 ; H01S 3/08 ;
U.S. Cl.
CPC ...
H01S 5/00 ; H01S 3/08 ;
Abstract
A ridge waveguide distributed feedback laser includes a p-type InGaAsP grating layer having a p-type carrier density ranging from 1.5×10 cm to 4.0×10 cm and preferably from 2.0×10 cm to 3.0×10 cm . In combination with such raised levels of p-type carrier density in the InGaAsP grating layer, the p-type carrier density may also be enhanced both in a p-type InP layer between the grating layer and a contact layer, and in another p-type InP layer between the grating layer and a quantum well active layer, the density ranging from 1.5×10 cm to 4.0×10 cm and preferably from 2.0×10 cm to 3.0×10 cm .