LIQUID CRYSTAL DISPLAY

• US 20120113342A1
• Filed: 01/18/2012
• Published: 05/10/2012
• Est. Priority Date: 10/03/2008
• Status: Active Grant

• Current Assignee: HannStar Display Corporation
• Original Assignee: HannStar Display Corporation
• Inventors: Chen, Po-Yang, Shih, Po-Sheng
• Granted Patent: US 8,228,451 B2
• Time in Patent Office: Days
• US Class Current: 349/38
• CPC Class Codes: G02F 1/13624 having more than one switching element per pixel
• 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 2300/0876 Supplementary capacities in pixels having special driving circuits and electrodes instead of being connected to common electrode or ground; Use of additional capacitively coupled compensation electrodes
• CPC Class Codes: G09G 2320/028 by changing the viewing angle properties, e.g. widening the viewing angle, adapting the viewing angle to the view direction
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence

Abstract

A liquid crystal display is provided. A pixel of the liquid crystal display includes a first pixel capacitor, a second pixel capacitor, a first transistor, and a second transistor. A first terminal and a second terminal of the first pixel capacitor are respectively coupled to the first transistor and a common voltage. A first terminal and a second terminal of the second pixel capacitor are respectively coupled to the second transistor and the common voltage. A voltage between the first and the second terminals of the first capacitor is differentiated from a voltage between the first and the second terminals of the second capacitor by modulating the common voltage. A coupling voltage of the first pixel capacitor is differentiated from a coupling voltage of the second pixel capacitor by modulating the common voltage. Thereby, the phenomenon of color wash-out is reduced.

Claims

1. A liquid crystal display (LCD), comprising:

a substrate and an opposite substrate corresponding to the substrate;

a bias electrode and a common electrode, disposed on the substrate;

a first pixel electrode, partially overlapping the bias electrode and the common electrode to respectively form a first storage capacitor having a capacitance C_st1 and a third storage capacitor having a capacitance C_st3;

a second pixel electrode, partially overlapping the bias electrode and the common electrode to respectively form a second storage capacitor having a capacitance C_st2 and a fourth storage capacitor having a capacitance C_st4; and

a mutual electrode, disposed on the opposite substrate and respectively overlapping the first pixel electrode and the second pixel electrode to form a first pixel capacitor having a capacitance C_lc1 and a second pixel capacitor having a capacitance C_lc2, wherein

2. The liquid crystal display according to claim 1, wherein an overlap area of the first pixel electrode and the bias electrode is different from an overlap area of the second pixel electrode and the bias electrode.

3. The liquid crystal display according to claim 1, wherein an overlap area of the first pixel electrode and the common electrode is different from an overlap area of the second pixel electrode and the common electrode.

4. The liquid crystal display according to claim 1, wherein an overlap area of the mutual electrode and the first pixel electrode is different from an overlap area of the mutual electrode and the second pixel electrode.

5. The liquid crystal display according to claim 1, wherein the bias electrode and the common electrode are formed in one piece.

6. The liquid crystal display according to claim 5, wherein the capacitance C_st3 of the third storage capacitor is 0, and the capacitance C_st4 of the fourth storage capacitor is also 0.

7. The liquid crystal display according to claim 1, wherein the bias electrode has a first opening and a second opening.

8. The liquid crystal display according to claim 7, wherein the first pixel electrode corresponds to the first opening.

9. The liquid crystal display according to claim 7, wherein the second pixel electrode corresponds to the second opening.

10. The liquid crystal display according to claim 1, wherein the first pixel electrode has a third opening.

11. The liquid crystal display according to claim 10, wherein the third opening is in a central position of the first pixel electrode.

12. The liquid crystal display according to claim 1, wherein the second pixel electrode has a fourth opening.

13. The liquid crystal display according to claim 12, wherein the fourth opening is in a central position of the second pixel electrode.

14. The liquid crystal display according to claim 1, wherein the first pixel electrode is a transparent electrode, and the second pixel electrode is an opaque electrode.