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:
Oct. 26, 1999
Filed:
Jan. 28, 1997
Masahiko Osada, Hekinan, JP;
Ken Nishioka, Toyoake, JP;
Hiroyuki Kishita, Kariya, JP;
Tadashi Hattori, Okazaki, JP;
Denso Corporation, Kariya, JP;
Abstract
To eliminate uneven luminance between columns, and along with this, to eliminate uneven luminance also among EL elements in several columns in an EL display device for performing matrix display, in a matrix type EL display device in which a scan voltage is sequentially applied to scan electrodes and EL elements are caused to electroluminesce by this scan voltage and a data voltage, a pulse width of the scan voltage is kept uniform, and together with this, a charging period for the EL elements is varied in accordance with a number of light emitting pixels in a line scanned and driven to eliminate uneven luminance between columns. Additionally, a holding period for holding a charging voltage is provided to alleviate differences in terminal voltages among the EL elements due to wiring resistance delay and to eliminate uneven luminance among the EL elements.