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:
Jul. 16, 2019
Filed:
Sep. 12, 2016
Semiconductor Energy Laboratory Co., Ltd., Atsugi-shi, Kanagawa-ken, JP;
Hajime Kimura, Kanagawa, JP;
Yoshifumi Tanada, Kanagawa, JP;
Semiconductor Energy Laboratory Co., Ltd., Atsugi-shi, Kanagawa-ken, JP;
Abstract
Display irregularities in light emitting devices, which develop due to dispersions per pixel in the threshold value of TFTs for supplying electric current to light emitting elements, are obstacles to increasing the image quality of the light emitting devices. An electric potential in which the threshold voltage of a TFT () is either added to or subtracted from the electric potential of a reset signal line () is stored in capacitor means (). A voltage, in which the corresponding threshold voltage is added to an image signal, is applied to a gate electrode of a TFT (). TFTs within a pixel are disposed adjacently, and dispersion in the characteristics of the TFTs does not easily develop. The threshold value of the TFT () is thus cancelled, even if the threshold values of the TFTs () differ per pixel, and a predetermined drain current can be supplied to an EL element ().