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. 23, 1991
Filed:
Nov. 16, 1988
Masahito Migita, Hachioji, JP;
Tsuyoshi Uda, Kodaira, JP;
Osam Kanehisa, Kodaira, JP;
Masatoshi Shiiki, Musashimuraya, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A semiconductor optical apparatus of the invention has a quantum well super-lattice structure essentially of only direct transition semiconductor or comprising a direct transition semiconductor and an indirect transiton semiconductor. In the semiconductor optical apparatus of the invention, by using an absorption saturation phenomenon of excitions in the direct transition semiconductor constructing the quantum well super-lattice structure, a non-volatile information recording apparatus which can record, reproduce, and erase information at a high speed even at the room temperature or even by irradiating a light of a low intensity is realized.