IP Library Granted Patent US 7,633,575
Granted Patent B2
US 7,633,575 · App. 12/157,066 · Granted Dec 15, 2009

Liquid crystal display device with pixel electrode voltage differential

View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 7,633,575
App. No.
12/157,066
Granted
Dec 15, 2009
Kind
B2
Abstract

An exemplary liquid crystal display ( 100 ) includes gate lines ( 122 ), and data lines ( 123 ) cooperatively defining pixel units. Each pixel unit includes a first thin film transistor (TFT) ( 125 ), a second TFT ( 126 ), a first pixel electrode ( 127 ), and a second pixel electrode ( 128 ). Gate electrodes of the two TFTs are connected to one of the gate lines. A source electrode of the first TFT is connected to one of the data lines. A drain electrode of the first TFT is connected to the first pixel electrode. A source electrode of the second TFT is connected to the first pixel electrode. A drain electrode of the second TFT is connected to the second pixel electrode. A channel width/length ratio of the second TFT is such that a voltage of the drain electrode thereof is less than a voltage of the source electrode thereof when the second TFT is switched on.

Claims (33)

1. A liquid crystal display comprising:

a plurality of gate lines parallel to each other; and

a plurality of data lines parallel to each other and intersecting with the gate lines, every two adjacent gate lines and every two adjacent data lines defining a pixel unit, each pixel unit comprising:

a first thin film transistor,

a second thin film transistor,

a first pixel electrode, and

a second pixel electrode,

gate electrodes of the first and second thin film transistors being connected to a same one of the gate lines, a source electrode of the first thin film transistor being connected to a corresponding one of the data lines, a drain electrode of the first thin film transistor being connected to the first pixel electrode, a source electrode of the second thin film transistor being connected to the first pixel electrode, and a drain electrode of the second thin film transistor being connected to the second pixel electrode, a channel width/length ratio of the second thin film transistor being such that a voltage of the drain electrode of the second thin film transistor is less than a voltage of the corresponding source electrode when the second thin film transistor is switched on.

2. The liquid crystal display of claim 1 , wherein the channel width/length ratio of the second thin film transistor is 5/10.

3. The liquid crystal display of claim 1 , wherein a channel width/length ratio of the first thin film transistor is such that a voltage of the drain electrode of the first thin film transistor is equal to a voltage of the corresponding source electrode when the first thin film transistor is switched on.

4. The liquid crystal display of claim 3 , wherein the channel width/length ratio of the first thin film transistor is 15/5.

5. The liquid crystal display of claim 1 , wherein a channel width/length ratio of the first thin film transistor is such that a voltage of the drain electrode of the first thin film transistor is less than a voltage of the corresponding source electrode when the first thin film transistor is switched on.

6. The liquid crystal display of claim 5 , wherein the channel width/length ratio of the first thin film transistor is 5/10.

7. The liquid crystal display of claim 1 , wherein a part of the first pixel electrode where the first pixel electrode joins the source electrode of the second thin film transistor forms a resistor.

8. The liquid crystal display of claim 7 , wherein said part of the first pixel electrode is elongate.

9. The liquid crystal display of claim 7 , wherein said part of the first pixel electrode is square-wave-shaped.

10. A liquid crystal display comprising:

a plurality of gate lines parallel to each other, and

a plurality of data lines parallel to each other and intersecting with the gate lines, every two adjacent gate lines and every two adjacent data lines defining a pixel unit, each pixel unit comprising:

a first pixel electrode,

a second pixel electrode,

a first thin film transistor, a gate electrode of the first thin film transistor being connected to a corresponding one of the gate lines, a source electrode of the first thin film transistor being connected to a corresponding one of the data lines, a drain electrode of the first thin film transistor being connected to the first pixel electrode, and

a resistor assembly, the resistor assembly connecting the first pixel electrode and the second pixel electrode and configured to render a voltage of the first pixel electrode different from a voltage of the second pixel electrode when a same data voltage is applied to the pixel unit.

11. The liquid crystal display of claim 10 , wherein the resistor assembly comprises a second thin film transistor, which comprises a gate electrode connected to the same gate line that the first thin film transistor is connected to, a source electrode connected to the first pixel electrode, and a drain electrode connected to the second pixel electrode.

12. The liquid crystal display of claim 11 , wherein a channel width/length ratio of the second thin film transistor is such that a voltage of the drain electrode of the second thin film transistor is less than a voltage of the corresponding source electrode when the second thin film transistor is switched on.

13. The liquid crystal display of claim 12 , wherein the channel width/length ratio of the second thin film transistor is 5/10.

14. The liquid crystal display of claim 10 , wherein the resistor assembly comprises a second thin film transistor, which comprises a gate electrode connected to the same gate line that the first thin film transistor is connected to, a source electrode connected to the drain electrode of the first thin film transistor, and a drain electrode connected to the second pixel electrode.

15. The liquid crystal display of claim 14 , wherein a channel width/length ratio of the second thin film transistor is such that a voltage of the drain electrode of the second thin film transistor is less than a voltage of the corresponding source electrode when the second thin film transistor is switched on.

16. The liquid crystal display of claim 15 , wherein the channel width/length ratio of the second thin film transistor is 5/10.

17. The liquid crystal display of claim 11 , wherein the resistor assembly further comprises a metal resistor interconnecting the first pixel electrode and the source electrode of the second thin film transistor.

18. The liquid crystal display of claim 17 , wherein the metal resistor is one of elongate and square-wave-shaped.

19. The liquid crystal display of claim 11 , wherein a part of the first pixel electrode where the first pixel electrode joins the source electrode of the second thin film transistor is one of elongate or and square-wave-shaped.

20. The liquid crystal display of claim 10 , wherein the resistor assembly comprises a metal resistor interconnecting the first pixel electrode and the second pixel electrode, the metal resistor being one of elongate and square-wave-shaped.

Assignments (3)
CHANGE OF NAME Recorded Apr 13, 2014
From: INNOLUX DISPLAY CORP.
To: CHIMEI INNOLUX CORPORATION
Reel/Frame 032672/0685 →
CHANGE OF NAME Recorded Apr 13, 2014
From: CHIMEI INNOLUX CORPORATION
To: INNOLUX CORPORATION
Reel/Frame 032672/0746 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jun 6, 2008
From: CHEN, CHIEN-CHENG; LIN, YU-CHENG
To: INNOLUX DISPLAY CORP.
Reel/Frame 021112/0442 →