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:
Nov. 07, 2017
Filed:
Mar. 20, 2017
Semiconductor Energy Laboratory Co., Ltd., Atsugi-shi, Kanagawa-ken, JP;
Hiroko Abe, Tokyo, JP;
Semiconductor Energy Laboratory Co., Ltd., Atsugi-shi, Kanagawa-ken, JP;
Abstract
An electroluminescent element which can easily control the balance of color in white emission (white balance) is provided according to the present invention. The electroluminescent element comprises a first light-emitting layer containing one kind or two or more kinds of light-emitting materials, and a second light-emitting layer containing two kinds of light-emitting materials (a host material and a phosphorescent material) in which the phosphorescent material is doped at a concentration of from 10 to 40 wt %, preferably, from 12.3 to 20 wt %. Consequently, blue emission can be obtained from the first light-emitting layer and green and red (or orange) emission can be obtained from the second light-emitting layer. An electroluminescent element having such device configuration can easily control white balance since emission peak intensity changes at the same rate in case of increasing a current density.