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:
Apr. 05, 1977
Filed:
Aug. 28, 1975
Kunio Itoh, Takatsuki, JA;
Morio Inoue, Takatsuki, JA;
Matsushita Electronics Corporation, Oaza-Kadoma, JA;
Abstract
A double-heterostructure injection laser can be improved to have a low threshold current. The improvement is obtained when the active region of GaAs or Ga.sub.l-y Al.sub.y As consists of several component layers wherein the central layer has the highest carrier concentrations and the layers on both sides of the central layer have lower carrier concentrations and the farther the outer layers are apart from the central layer, the lower are their carrier concentrations. By forming the active region in this manner, the light generated in the active region is well confined in the region without undesirable leaking, resulting in a considerable lowering of the threshold current.