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. 26, 2026
Filed:
Feb. 22, 2023
Semiconductor Energy Laboratory Co., Ltd., Atsugi, JP;
SEMICONDUCTOR ENERGY LABORATORY CO., LTD., Kanagawa-ken, JP;
Abstract
To provide a light-emitting device with high emission efficiency and high reliability. A light-emitting layer of the light-emitting device includes a first substance emitting light from a doublet excited state based on f-d transition and a second substance that is a fluorescent substance. The longest-wavelength absorption edge among absorption edges in the absorption spectrum of the first substance is positioned at a wavelength shorter than the wavelength of the longest-wavelength absorption edge among absorption edges in the absorption spectrum of the second substance. The first substance has a short exciton lifetime and high exciton generation efficiency, and efficient energy transfer occurs between the first substance and the second substance; thus, the light-emitting device can have high emission efficiency and high reliability.