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:
Dec. 30, 2008
Filed:
Feb. 07, 2005
Akinori Hayafuji, Yonezawa, JP;
Katsuhiro Kanauchi, Yonezawa, JP;
Akinori Hayafuji, Yonezawa, JP;
Katsuhiro Kanauchi, Yonezawa, JP;
Tohoku Pioneer Corporation, Yamagata, JP;
Abstract
A clock signal in synchronization with a data writing signal, every scanning line, which is supplied from a light-emitting control circuitto a scanning driver, is supplied to an oscillatorwhich generates a reference switching signal, according to a PWM method, in a DC-DC converter. Thereby, the timing at data writing every scanning line is in synchronization with the phase of a ripple component superimposed on a driving voltage Va from the DC-DC converter. Accordingly, a problem that there is caused a state in which light-emitting intensity is different every scanning line can be solved because the same voltage Vgs between a gate and a source is supplied every scanning line to a light-emitting driving transistor Trat any time even if the ripple component by switching of the DC-DC converter is superimposed on the driving voltage Va. Thereby, a problem that the display quality of images is remarkably reduced can be prevented in a light-emitting driving operation of a display panel, wherein the operation has a configuration in which an organic EL element with a light-emitting intensity characteristic of a current dependence type, for example, is used as a pixel.