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:
Apr. 19, 2016
Filed:
May. 23, 2013
Semiconductor Energy Laboratory Co., Ltd., Atsugi-shi, Kanagawa-ken, JP;
Hiroyuki Miyake, Atsugi, JP;
Kenichi Okazaki, Tochigi, JP;
Toshiyuki Miyamoto, Kanuma, JP;
Masafumi Nomura, Tochigi, JP;
Takashi Hamochi, Shimotsuga, JP;
Shunpei Yamazaki, Setagaya, JP;
Semiconductor Energy Laboratory Co., Ltd., Kanagawa-ken, JP;
Abstract
A light-emitting device that is less influenced by variations in threshold voltage of a transistor is provided. Further, a light-emitting device in which variations in luminance due to variations in threshold voltage of a transistor can be reduced is provided. Further, influences due to variations in threshold voltage of a transistor are corrected in a short time. A light-emitting element, a transistor functioning as a switch supplying current to the light-emitting element, and a circuit in which threshold voltage of the transistor is obtained and voltage between a gate and a source (gate voltage) of the transistor is corrected in accordance with the obtained threshold voltage are included. An n-channel transistor in which threshold voltage changes in a positive direction and the amount of the change is small is used. When the threshold voltage of the transistor is obtained, the gate voltage of the transistor is adjusted as appropriate.