Liquid crystal display

• US 9,134,581 B2
• Filed: 07/12/2011
• Issued: 09/15/2015
• Est. Priority Date: 11/26/2007
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: Yang, Young-Chol, Lu, JianGang, Lee, Seung-Hoon
• Primary Examiner(s): Nguyen, Jimmy H
• Application Number:
  US13/181,102
• Publication Number:
  US 20110267554A1
• Time in Patent Office: 1,526 Days
• Field of Search: 345 90- 93, 349/38, 349/39, 349/42
• US Class Current: 1/1
• CPC Class Codes: G02F 1/134345 Subdivided pixels, e.g. for grey scale or redundancy
• CPC Class Codes: G02F 1/13624 having more than one switching element per pixel
• CPC Class Codes: G02F 1/1393 the birefringence of the liquid crystal being electrically controlled, e.g. ECB-, DAP-, HAN-, PI-LC cells G02F1/1396, G02F1/141 take precedence
• CPC Class Codes: G09G 2300/0443 with several sub-pixels for the same colour in a pixel, not specifically used to display gradations G09G3/364 takes precedence
• CPC Class Codes: G09G 2300/0447 for multi-domain technique to improve the viewing angle in a liquid crystal display, such as multi-vertical alignment [MVA]
• CPC Class Codes: G09G 2300/0814 used for selection purposes, e.g. logical AND for partial update
• CPC Class Codes: G09G 2300/0842 forming a memory circuit, e.g. a dynamic memory with one capacitor
• CPC Class Codes: G09G 2320/068 for control of viewing angle adjustment
• CPC Class Codes: G09G 3/3659 the addressing of the pixel involving the control of two or more scan electrodes or two or more data electrodes, e.g. pixel voltage dependant on signal of two data electrodes

Abstract

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.

Claims

1. A display device comprising:

a gate line;

a data line crossing the gate line;

a pixel electrode comprising a first sub-pixel electrode and a second sub-pixel electrode;

a first switching element electrically connected to the gate line, the data line, and the first sub-pixel electrode;

a second switching element electrically connected to the gate line, the data line, and the second sub-pixel electrode; and

a third switching element electrically connected to the gate line, the first sub-pixel electrode, and a conductive line carrying a common voltage,

wherein the third switching element is electrically connected to the first sub-pixel electrode via an electrical connection through a charge-sharing capacitor,

wherein one terminal of the charge-sharing capacitor is directly connected to the first sub-pixel electrode and another terminal of the charge-sharing capacitor is directly connected to a terminal of the third switching element,

wherein the conductive line is directly connected to a first storage capacitor being different from the charge-storage capacitor and being directly connected to the one terminal of the charge-sharing capacitor and the first sub-pixel electrode, and

wherein the electrical connection is not through the first switching element, the conductive line, and the gate line.

2. The display device of claim 1, wherein a voltage of the first sub-pixel electrode is different from a voltage of the second sub-pixel electrode.

3. The display device of claim 2, wherein the first sub-pixel electrode and the second sub-pixel electrode are insulated from each other.

4. The display device of claim 3, wherein the conductive line is a storage line.

5. The display device of claim 2, wherein the conductive line is a storage line.

6. The display device of claim 1, wherein the first sub-pixel electrode and the second sub-pixel electrode are insulated from each other.

7. The display device of claim 6, wherein the conductive line is a storage line.

8. The display device of claim 1, wherein the conductive line is a storage line.

9. The display device of claim 1, wherein the charge-sharing capacitor is formed by an output terminal of the first thin film transistor, an output terminal of the third thin film transistor, and an insulator between the output terminal of the first switching element and the output terminal of the third switching element.

10. The display device of claim 9, wherein the third switching element is directly connected to the conductive line via an input terminal of the third switching element.

11. A display device comprising:

a gate line;

a data line crossing the gate line;

a pixel electrode comprising a first sub-pixel electrode and a second sub-pixel electrode;

a first thin film transistor comprising a first terminal connected to the gate line, a second terminal connected to the data line, and a third terminal connected to the first sub-pixel electrode;

a second thin film transistor comprising a first terminal connected to the gate line, a second terminal connected to the data line, and a third terminal connected to the second sub-pixel electrode; and

a third thin film transistor comprising a first terminal connected to the gate line, a second terminal connected to the third terminal of the first thin film transistor via an electrical connection through a charge-sharing capacitor, and a third terminal connected to a conductive line carrying a common voltage,

wherein one terminal of the charge-sharing capacitor is directly connected to the first sub-pixel electrode and another terminal of the charge-sharing capacitor is directly connected to the second terminal of the third thin film transistor,

wherein the conductive line is directly connected to a first storage capacitor being different from the charge-storage capacitor and being directly connected to the one terminal of the charge-sharing capacitor and the first sub-pixel electrode, and

wherein the electrical connection is not through the first thin film transistor, the conductive line, and the gate line.

12. The display device of claim 11, wherein the conductive line is a storage line.

13. The display device of claim 11, wherein the charge-sharing capacitor is formed by the third terminal of the first thin film transistor, the second terminal of the third thin film transistor, and an insulator between the second terminal of the third thin film transistor and the third terminal of the first thin film transistor.

14. The display device of claim 13, wherein the third terminal of the third thin film transistor is directly connected to the conductive line.