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:
Sep. 18, 2001
Filed:
Jun. 03, 1998
Naohiro Shimada, Yokosuka, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
An InGaAlP active region,which substantially lattice-matches with a GaAs substrate,has a multiple quantum well structure (MQW) formed by quantum well layers,of InGaP. When the oscillating wavelength caused by the current injection is less than or equal to 670 nm, the thickness (Lz) of the InGaP quantum well layers,is set to be less than 8 nm to form a lattice mismatching so that the quantum well layers,have a greater lattice constant than that of the GaAs substrate,and a compressive strain is added to the quantum well layers,Thus, gain is increased by reducing the thickness of the quantum well layers,and adding the compressive strain thereto, so that it is possible to achieve the improvement of the temperature characteristics, such as a reduced threshold, an improved efficiency, and a reduced current during operation at a high temperature, in a laser having an oscillating wavelength of 650 nm.