Method and system of compensating kickback voltage for a liquid crystal display device
AssigneeLG. Philips LCD Co., Ltd.
InventorJin-Cheol Hong
Life of this patent
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Abstract
A system for compensating for a kickback voltage for a common electrode of a LCD device having a gate line where the gate signal is applied from a first end to a second. The system includes a mechanism configured to apply a constant current to the common electrode at a location corresponding to the first end of the gate line, and mechanism configured to apply a common voltage to the common electrode at a location corresponding to the second end of the gate line. The constant current applied to the common electrode helps to maintain the difference of the common voltages between the positions corresponding to first and second ends of the gate line.
Claims22
An active matrix type liquid crystal display (LCD) system, comprising:
- a first substrate including a plurality of pixel electrodes arranged in matrix form, a plurality of thin film transistors each having a gate electrode and a source electrode, a plurality of data lines transmitting data signals to the source electrodes, and a plurality of gate lines transmitting gate signals to the gate electrodes from a first end to a second end of each gate line;
- a second substrate opposing to the first substrate, the second substrate having a common electrode facing the plurality of pixel electrodes of the first substrate;
- a liquid crystal layer between the first and second substrates;
- a gate line driving circuit transmitting the gate signals to first ends of the plurality of gate lines;
- a data line driving circuit transmitting the data signals to the plurality of data lines;
- a constant current source for supplying a constant current to a first side of the common electrode corresponding to one of the first ends of the gate lines, the first side having a first contact resistance;
- a common voltage supply for applying a common voltage to a second side of the common electrode corresponding to the second end of the one gate line, the second side having a second contact resistance;
- first and second connection points between the first and second substrates, respectively, through the first and second connection points the constant current and the common voltage being transmitted to the second substrate from the first substrate;
- and
- wherein the first contact resistance is between the first side of the common electrode and the first connection point, and wherein the second contact resistance is between the second side of the common electrode and the second connection point.
A liquid crystal display (LCD) device, comprising:
- a first substrate including a plurality of thin film transistors each having,
- a gate electrode, a source electrode, and a drain electrode, and
- a plurality of pixel electrodes each connected to a corresponding drain electrode,
- a plurality of data lines transmitting data signals to a corresponding source electrode, and
- a plurality of gate lines transmitting gate signals to a corresponding the gate electrode;
- a second substrate opposing to the first substrate, the second substrate having a common electrode facing the plurality of pixel electrodes of the first substrate;
- and
- a liquid crystal layer between the first and second substrates;
- wherein a constant current is applied to a first side of the common electrode, and
- wherein a common voltage is applied to a second side of the common electrode.
A liquid crystal display (LCD) panel, comprising:
- a first substrate including a plurality of thin film transistors each having,
- a gate electrode, a source electrode, and a drain electrode, and
- a plurality of pixel electrodes each connected to a corresponding drain electrodes,
- a plurality of data lines transmitting data signals to a corresponding source electrode, and
- a plurality of gate lines transmitting gate signals to the a corresponding gate electrode;
- a second substrate opposing to the first substrate, the second substrate having a common electrode facing the plurality of pixel electrodes of the first substrate;
- a liquid crystal layer between the first and second substrates;
- a constant current source for applying a constant current to a first side of the common electrode;
- and
- a common voltage supply for applying a common voltage to a second side of the common electrode.
Dependencies are inferred from the claim text.