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:
Jan. 07, 1986
Filed:
Sep. 13, 1983
Takao Kuroda, Kokubunji, JP;
Takashi Kajimura, Hinodemachi, JP;
Yasutoshi Kashiwada, Hinodemachi, JP;
Naoki Chinone, Hachioji, JP;
Hirobumi Ouchi, Hino, JP;
Tsukuru Ohtoshi, Kokubunji, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
Disclosed is a semiconductor laser device having at least an optical confinement region which includes a first semiconductor layer, and second and third semiconductor layers holding the first semiconductor layer therebetween and having a greater band gap and a lower refractive index than those of the first semiconductor layer, the second and third semiconductor layers having conductivity types opposite to each other; characterized in that the relationship between a donor density (N.sub.D .times.10.sup.17 cm.sup.-3) of the n-conductivity type semiconductor layer in the second and third semiconductor layers and a proportion (.GAMMA..sub.n %) of an optical output existing in the n-conductivity type semiconductor layer relative to a total optical output of the laser is set at N.sub.D .times..GAMMA..sub.n .gtoreq.500. Noise characteristics are sharply improved.