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:
May. 31, 2011
Filed:
Aug. 12, 2005
Atsushi Tokuda, Kanagawa, JP;
Masakazu Egawa, Kanagawa, JP;
Atsushi Tokuda, Kanagawa, JP;
Masakazu Egawa, Kanagawa, JP;
Abstract
According to the present invention, a light-emitting element, a light-emitting device, and a lighting system, each of which has a broad spectrum like sunlight and has high color rendering properties, can be obtained. One embodiment of the present invention has a light-emitting device which includes at least two kinds of luminescence center materials, and at least one kind of the luminescence center materials is a quinoxaline derivative represented by the following general formula (1): wherein R1 to R4 are individually hydrogen or an alkyl group having 4 carbon atoms (a straight-chain structure or a branch structure).