Title:
ACTIVE MATRIX TYPE LIQUID CRYSTAL DISPLAY DEVICE
Document Type and Number:
Japanese Patent JPH01291216
Kind Code:
A
Abstract:
PURPOSE:To prevent the deterioration of the drain current-gate voltage characteristics of TFTs from an initial state and to stabilize the contrast of a liquid crystal cell by turning on and off at least one of the two TFTs connected in series with a voltage of about 50% duty ratio. CONSTITUTION:The TFTs 1, 2 are connected in series. One end of the liquid crystal cell 3 is connected to a counter electrode 7 and the other end to the TFT 2. The TFT 1 is connected to a data electrode 4 and the gates of the TFTs 1, 2 are respectively connected to independent scanning electrodes 5, 6. The voltage set at about 50% duty ratio is impressed to at least either of the electrodes 5, 6. Shifting of the drain current-gate voltage characteristics of the TFTs to a plus direction and shifting thereof to a minus direction are thereby canceled and the drain current-gate voltage characteristics of the TFTs do not change from the initial characteristics. The degradation in the contrast of the liquid crystal cell 3 is obviated.
Inventors:
YAMAGUCHI TADAHISA
HOSHINO TAKAYUKI
TAKAHARA KAZUHIRO
HOSHINO TAKAYUKI
TAKAHARA KAZUHIRO
Application Number:
JP12051488A
Publication Date:
November 22, 1989
Filing Date:
May 19, 1988
Export Citation:
Assignee:
FUJITSU LTD
International Classes:
G09G3/36; G02F1/133; G02F1/136; G02F1/1368; (IPC1-7): G02F1/133; G09G3/36
Attorney, Agent or Firm:
Aoki Akira (4 outside)