Title:
DRIVE METHOD FOR DISPLAY DEVICE
Document Type and Number:
Japanese Patent JP2002108285
Kind Code:
A
Abstract:
To suppress variance in luminance display caused by the characteristic dispersion of TFTs(Thin Film Transistors) constituting pixcels and changes in environmental temperature at which the active matrix type EL(Electroluminescence) display device is used.
A time gradation system is used. By operating an EL driving TFT in an ON condition and in a saturation region, the drain current of the TFT is held at a constant value. Thus, a constant current flows in an EL element and the active matrix type EL display device having an accurate gradation display with high image quality is realized.
Inventors:
KOYAMA JUN
Application Number:
JP2001224422A
Publication Date:
April 10, 2002
Filing Date:
July 25, 2001
Export Citation:
Assignee:
SEMICONDUCTOR ENERGY LAB
International Classes:
H05B44/00; G09F9/30; G09G3/20; G09G3/30; H01L27/32; H01L51/50; H05B33/12; H05B33/14; (IPC1-7): G09G3/30; G09F9/30; G09G3/20; H05B33/08; H05B33/12; H05B33/14
Domestic Patent References:
| JPH10214060A | 1998-08-11 | |||
| JPH10254410A | 1998-09-25 | |||
| JPH0916123A | 1997-01-17 |
Other References:
MARK STEWART, 他５名: "Polysilicon VGA Active Matrix OLED Displays - Technology and Performance", ELECTRON DEVICES MEETING, 1998. IEDM '98 TECHNICAL DIGEST., INTERNATIONAL, JPN6012009339, 6 December 1998 (1998-12-06), US, pages 871 - 874, ISSN: 0002155322
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