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. 11, 1986
Filed:
May. 07, 1984
Applicant:
Inventor:
Ikuo Mito, Tokyo, JP;
Assignee:
NEC, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01S / ;
U.S. Cl.
CPC ...
372 45 ; 372 48 ; 372 50 ; 372 96 ;
Abstract
A single longitudinal mode semiconductor laser having a distributed Bragg reflector with increased diffractive efficiency. The increased diffractive efficiency results from placing the diffraction grating within the optical waveguide, rather than on either its upper or its lower face. This placement enables maximization of the electric field component of light beams subjected to periodic variations in the refractive index within the optical waveguide, in turn enabling increased reflecting power which results in a low oscillation threshold and a high differential quantum efficiency.