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. 21, 1992
Filed:
Aug. 07, 1991
Applicant:
Inventors:
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
357-4 ; 357 16 ; 357 30 ; 357 45 ; 357 17 ;
Abstract
A semiconductor optical modulator is provided wherein very thin films of two kinds of semiconductors having different band gaps are laminated alternately to form a multi-quantum well (MQW) structure, also called a super-lattice structure, and current is injected into the MQW structure to change the corresponding optical absorption and refractive index characteristic thereof so that a sufficient on/off ratio can be obtained.