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:
Jun. 22, 1999
Filed:
Oct. 10, 1997
Toshikazu Mukaihara, Yokohama, JP;
Akihiko Kasukawa, Tokyo, JP;
The Furukawa Electric Co., Ltd., Tokyo, JP;
Abstract
A reflection multilayer including low-refraction layers and semiconductor layers is formed on the facets of a semiconductor laser. The bandgap energy (Ewg) of a waveguide layer of the reflection multilayer is greater than the bandgap energy (Eac) of an active layer of the semiconductor laser (Eac<Ewg), while the thickness (Twg) of the former is smaller than the thickness (Tac) of the latter (Tac>Twg). Further, a photodetector and an optical modulator are formed on the semiconductor laser with the reflection multilayer thereon by butt-Jointing or monolithically by selective vapor growth with use of selective growth masks. Relations Ewg>Emod>Eac>Epd and Twg>Tmod>Tac>Tpd are established between the respective bandgap energies and thicknesses of individual layers, whereby the absorption rate of the reflector waveguide layer and diffraction loss are lowered or reduced, and the rates of optical absorption in an optical absorption layer of the photodetector are increased.