Liquid crystal display
View Patent ↗A liquid crystal display includes first and second gate lines arranged in parallel to each other and sequentially transmitting a gate voltage, a data line crossing the first and second gate lines and transmitting a data voltage, a pixel electrode constituted by first and second sub-pixel electrodes and electrically disconnected from each other, a first switching element connected to the first gate line, the data line, and the first sub-pixel electrode, a second switching element connected to the first gate line, the data line, and the second sub-pixel electrode, a third switching element connected to the first sub-pixel electrode across a charge-sharing capacitor, and a fourth switching element connected to the second gate line and the second sub-pixel electrode and connected to the first sub-pixel electrode across the charge-sharing capacitor.
1. A liquid crystal display comprising:
first and second gate lines arranged in parallel to each other and sequentially transmitting a gate voltage;
a data line crossing the first and second gate lines and transmitting a data voltage;
a pixel electrode constituted by first and second sub-pixel electrodes electrically disconnected from each other;
a first switching element connected to the first gate line, the data line, and the first sub-pixel electrode;
a second switching element connected to the first gate line, the data line, and the second sub-pixel electrode;
a third switching element connected to the first sub-pixel electrode across a charge-sharing capacitor; and
a fourth switching element connected to the second gate line and the second sub-pixel electrode and connected to the first sub-pixel electrode across the charge-sharing capacitor.
2. The liquid crystal display of claim 1 , further comprising a storage line parallel to the gate lines and transmitting a common voltage, wherein the third switching element has a control terminal connected to the first gate line, an output terminal connected to the charge-sharing capacitor, and an input terminal connected to the storage line.
3. The liquid crystal display of claim 2 , wherein the input terminal of the third switching element is directly connected to the storage line.
4. The liquid crystal display of claim 3 , wherein when a gate-on voltage is applied to the first gate line, a voltage corresponding to a difference between the data voltage and the common voltage is charged in the charge-sharing capacitor.
5. The liquid crystal display of claim 2 , wherein the input terminal of the third switching element is connected to the storage line via an auxiliary capacitor.
6. The liquid crystal display of claim 1 , further comprising a charge-sharing wire parallel to the data line and transmitting a charge-sharing voltage, wherein the third switching element has a control terminal connected to the first gate line, an output terminal connected to the charge-sharing capacitor, and an input terminal connected to the charge-sharing wire.
7. The liquid crystal display of claim 6 , wherein the polarity of the charge-sharing voltage is opposite to the polarity of the data voltage.
8. The liquid crystal display of claim 6 , wherein after charge sharing is performed between the pixel voltages of the first and second sub-pixel electrodes, the pixel voltages of the first and second sub-pixel electrodes are boosted relative to the data voltage.
9. The liquid crystal display of claim 8 , further comprising:
a first liquid crystal (LC) capacitor and a first storage capacitor which are cascade-connected to the first switching element; and
a second LC capacitor and a second storage capacitor cascade-connected to the second switching element, wherein the data voltage and the charge-sharing voltage satisfy the following relationship:
Vm
Vp
≥
Ch
2
Cb
+
Ch
wherein Vp is a data voltage, Vm is a charge-sharing voltage, Ch denotes a capacitance sum of the first LC capacitor and the first storage capacitor, and Cb denotes a capacitance of the charge-sharing capacitor.
10. The liquid crystal display of claim 1 , further comprising lower and upper panels facing each other, and a liquid crystal layer interposed between the panels.
11. A liquid crystal display comprising:
a gate driver driving first and second gate lines arranged in parallel to each other and sequentially transmitting a gate voltage;
a data driver driving a data line crossing the first and second gate lines and transmitting a data voltage;
a signal controller controlling the gate driver and the data driver;
a pixel electrode constituted by first and second sub-pixel electrodes electrically disconnected from each other;
a first switching element connected to the first gate line, the data line, and the first sub-pixel electrode;
a second switching element connected to the first gate line, the data line, and the second sub-pixel electrode;
a third switching element connected to the first sub-pixel electrode across a charge-sharing capacitor; and
a fourth switching element connected to the second gate line and the second sub-pixel electrode and connected to the first sub-pixel electrode across the charge-sharing capacitor.
12. The liquid crystal display of claim 11 , further comprising a storage line parallel to the gate lines and transmitting a common voltage, wherein the third switching element has a control terminal connected to the first gate line, an output terminal connected to the charge-sharing capacitor, and an input terminal connected to the storage line.
13. The liquid crystal display of claim 12 , wherein the input terminal of the third switching element is directly connected to the storage line.
14. The liquid crystal display of claim 13 , wherein when a gate-on voltage is applied to the first gate line, a voltage corresponding to a difference between the data voltage and the common voltage is charged in the charge-sharing capacitor.
15. The liquid crystal display of claim 12 , wherein the input terminal of the third switching element is connected to the storage line via an auxiliary capacitor.
16. The liquid crystal display of claim 11 , further comprising a charge-sharing wire parallel to the data line and transmitting a charge-sharing voltage, wherein the third switching element has a control terminal connected to the first gate line, an output terminal connected to the charge-sharing capacitor, and an input terminal connected to the charge-sharing wire.
17. The liquid crystal display of claim 16 , wherein the polarity of the charge-sharing voltage is opposite to the polarity of the data voltage.
18. The liquid crystal display of claim 16 , wherein after charge sharing is performed between the pixel voltages of the first and second sub-pixel electrodes, the pixel voltages of the first and second sub-pixel electrodes are boosted relative to the data voltage.
19. The liquid crystal display of claim 18 , further comprising:
a first liquid crystal (LC) capacitor and a first storage capacitor which are cascade-connected to the first switching element; and
a second LC capacitor and a second storage capacitor cascade-connected to the second switching element, wherein the data voltage and the charge-sharing voltage satisfy the following relationship:
Vm
Vp
≥
Ch
2
Cb
+
Ch
wherein Vp is a data voltage, Vm is a charge-sharing voltage, Ch denotes a capacitance sum of the first LC capacitor and the first storage capacitor, and Cb denotes a capacitance of the charge-sharing capacitor.
20. The liquid crystal display of claim 11 , further comprising lower and upper panels facing each other and a liquid crystal layer interposed between the panels.