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:
Sep. 10, 2019
Filed:
Jul. 17, 2018
Seiko Epson Corporation, Tokyo, JP;
Akio Fukase, Chino, JP;
Hidetoshi Yamamoto, Suwa, JP;
SEIKO EPSON CORPORATION, Tokyo, JP;
Abstract
Provided is a light emitting device configured to suppress deterioration in a balance of white light emission and increase a service life. The light emitting device includes a red light emitting layer, a blue light emitting layer, a green light emitting layer, a first intermediate layer configured to adjust a transfer of holes and electrons between the red light emitting layer and the blue light emitting layer, and a second intermediate layer configured to adjust the transfer of holes and electrons between the blue light emitting layer and the green light emitting layer. The intermediate layers and the blue light emitting layer each contain an assist dopant material, a concentration of the assist dopant material in the intermediate layers being greater than a concentration of the assist dopant material in the blue light emitting layer.