Title:
DISPLAY QUALITY IMPROVING CIRCUIT FOR LIQUID CRYSTAL DISPLAY
Document Type and Number:
Japanese Patent JPH03259217
Kind Code:
A
Abstract:
PURPOSE:To improve a defect in display quality due to the distortion of a driving waveform by using the output of an exclusive OR gate as a liquid crystal AC signal, repeating AC generation at intervals of plural common lines, and inverting the polarity of each frame signal alternately. CONSTITUTION:A segment driver latch signal LP is inverted by an inverter INV1 to activate the clock input terminal CK of a 1/N frequency dividing circuit 3. Further, the carry output terminal CY is inverted by an inverter INV2 and connected to a load terminal -LD to form a frequency dividing circuit which has an optional frequency division ratio. The output signal T2 of a flip- flop circuit is inputted to one terminal of an exclusive OR gate 6 and inverted and uninverted repeatedly with the liquid crystal AC signal DF connected to the other terminal to obtain an improved liquid crystal AC signal M. Further, the liquid crystal AC signal M is inverted in polarity at intervals of plural common lines and at intervals of a frame in one frame. Consequently, the defect in display quality such as a ghost is improved.
Inventors:
YOKOYAMA KOZO
Application Number:
JP5908890A
Publication Date:
November 19, 1991
Filing Date:
March 09, 1990
Export Citation:
Assignee:
SEIKO INSTR INC
International Classes:
G02F1/133; G09G3/36; (IPC1-7): G02F1/133; G09G3/36
Attorney, Agent or Firm:
Keinosuke Hayashi