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. 16, 1999
Filed:
Sep. 29, 1998
Applicant:
Inventors:
Assignee:
British Telecommunications public limited company, London, GB;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01S / ;
U.S. Cl.
CPC ...
438 31 ; 438 29 ; 438 39 ; 438 46 ; 372 45 ; 385 28 ; 385 49 ;
Abstract
A semiconductor optical device, for example a laser, has a composite optical waveguide including a tapered, MQW active waveguide in optical contact with a substantially planar, passive waveguide. The fundamental optical mode supported by the composite waveguide varies along the length of the composite waveguide so that, in a laser, the laser mode is enlarged and is a better match to single mode optical fibre. A method for making such semiconductor optical devices is also disclosed.