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:
Dec. 10, 2013
Filed:
May. 15, 2012
Yumi Fukuda, Tokyo, JP;
Hironori Asai, Yokohama, JP;
Yumi Fukuda, Tokyo, JP;
Hironori Asai, Yokohama, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
Provided is a fluorescent substance excellent in quantum efficiency and in temperature characteristics, and a light-emitting device utilizing the fluorescent substance. This fluorescent substance contains an inorganic compound comprising a metal element M, a trivalent element Mother than the metal element M, a tetravalent element Mother than the metal element M, and either or both of O and N. In the inorganic compound, the metal element M is partly replaced with a luminescence center element R. The crystal structure of the fluorescent substance is basically the same as SrAlSiON, but the chemical bond lengths of M-N and M-N are within the range of ±15% based on those of Al—N and Si—N calculated from the lattice constants and atomic coordinates of SrAlSiON, respectively. The fluorescent substance emits luminescence having a peak in the range of 490 to 580 nm when excited with light of 250 to 500 nm.