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:
Dec. 31, 2002
Filed:
Mar. 27, 1998
Applicant:
Inventors:
Kiyoshi Takei, Tsurugashima, JP;
Yoshiaki Watanabe, Tsurugashima, JP;
Nong Chen, Tsurugashima, JP;
Kiyofumi Chikuma, Asaka, JP;
Assignee:
Pioneer Electronic Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01S 5/30 ;
U.S. Cl.
CPC ...
H01S 5/30 ;
Abstract
A method for producing a distributed feedback semiconductor laser element includes the steps of forming a laser substrate, forming a ridge by etching the laser substrate, and forming a flattening layer on the ridge. A grating is then formed on the flattening layer and the grating is further transferred to the laser substrate on which the ridge is formed. The flattening layer is removed and electrodes are then formed.