Multi-Domain Vertical Alignment Liquid Crystal Displays With Improved Angular Dependent Gamma Curves

• US 20090021660A1
• Filed: 07/20/2007
• Published: 01/22/2009
• Est. Priority Date: 07/20/2007
• Status: Active Grant

• Current Assignee: InnoLux Corporation, University of Central Florida Research Foundation Inc. (State University System of Florida)
• Original Assignee: Chi Mei Innolux Corporation (InnoLux Corporation)
• Inventors: Li, Wang-Yang, Lu, Ruibo, Wu, Shin-Tson, Wei, Chung-Kuang, Lee, Seung-Hee
• Granted Patent: US 7,605,897 B2
• Time in Patent Office: Days
• US Class Current: 349/42
• CPC Class Codes: G02F 1/133707 Structures for producing distorted electric fields, e.g. bumps, protrusions, recesses, slits in pixel electrodes
• CPC Class Codes: G02F 1/133776 having structures locally influencing the alignment, e.g. unevenness
• 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

Abstract

Methods, systems and apparatus for a liquid crystal display panel having a first substrate with a color filter, an over-coating and a common electrode. The second substrate includes an insulating layer surface facing the first substrate, a pixel electrode, a plurality of common and pixel domain guides formed on the common and the pixel electrodes, a plurality of electric shields on one of the common or pixel electrodes and a liquid crystal layer vertically aligned between the first and second substrates. The panel also includes a drive circuit for applying a voltage to generate an electric field to control liquid crystal molecule orientation corresponding to the plurality of domain guides and electric shields to form a multi-domain liquid crystal display panel device. The plural domain guides are either protrusions or slits formed in the common electrode and the pixel electrode to form the multi-domain vertical alignment liquid crystal device.

Claims

1. A multi-domain vertical alignment liquid crystal display panel comprising:

a first substrate;

a second substrate having an insulating layer on an interior surface facing the first substrate and a passivation layer on the insulating layer;

an over-coating layer formed on at least a portion of one of the first substrate and the passivation layer;

a common electrode disposed on one of the first substrate and the over-coating layer on the first substrate;

a pixel electrode formed on the passivation layer when the over-coating layer is formed on the first substrate and when the over-coating layer is formed on the portion of the passivation layer, the pixel electrode formed on a remaining portion of the passivation layer adjacent to the over-coating layer and covering the over-coating layer;

a plurality of common and pixel domain guides formed respectively in the common electrode and the pixel electrode, the common domain guides nonaligned with the pixel domain guides;

an electric shield formed over the corresponding one of the common electrode and pixel electrode adjacent to the over-coating layer;

a vertically aligned liquid crystal layer sandwiched between the first and second substrates; and

a drive circuit connected with the common electrode and the pixel electrode for applying a voltage to generate an electric field between the first substrate and the second substrate to control a liquid crystal molecule orientation corresponding to a positioning of the plurality of common and pixel domain guides and plurality of electric shields to form a multi-domain vertical aligned liquid crystal display panel.

2. The liquid crystal display panel of claim 1, wherein a thickness of the said over-coating layer ranges from 0 μ

m to 50 μ

m.

3. The liquid crystal display panel of claim 1 wherein said electric shielding layer has an area ratio corresponding to said liquid crystal display panel is larger than 1:

1000.

4. The liquid crystal display panel of claim 1, wherein each of said plural common and pixel domain guides is a protrusion on the common electrode and the pixel electrode extending into said liquid crystal layer to form the multi-domain liquid crystal display configuration.

5. The liquid crystal display panel of claim 1, wherein each of said domain guides is a domain guide slit formed in the common electrode and the pixel electrode dividing the common electrode into at least two common electrodes and dividing the pixel electrode into at least two pixel electrodes to form the multi-domain liquid crystal configuration.

6. The liquid crystal display panel of claim 1, wherein the plural common and pixel domain guides comprise:

a common domain guide in the common electrode in each pixel region of the liquid crystal display panel; and

a pixel domain guide in the pixel electrode in each pixel region of the liquid crystal display panel, the common domain guide above and on one side of the pixel domain guide.

7. The liquid crystal display panel of claim 6, wherein the common domain guide is located above and on one side of the pixel domain guide and the electric shield is located above and on an opposite side of the pixel domain guide dividing the common electrode into a first, second and third common electrode to form an eight domain multi-domain vertical alignment liquid crystal display panel.

8. The liquid crystal display panel of claim 6, wherein the common domain guide is located above and on one side of the pixel domain guide and the electric shield is located above and on an opposite side of the pixel domain guide dividing the common electrode into a first and a second common electrode to form the multi-domain liquid crystal display panel having six domains in each pixel region.

9. The liquid crystal display panel of claim 6, wherein the common domain guide is located above and on one side of the pixel domain guide and the electric shield is located above and on an opposite side of the pixel domain guide dividing the common electrode into a first and a second electrodes to form the multi-domain liquid crystal display panel having eight domains in each pixel region.

10. The liquid crystal display panel of claim 6, wherein the common domain guide comprises:

a first and a second common domain guide on opposite sides of the pixel domain guide dividing the common electrode into at least two common electrodes.

11. The liquid crystal display panel of claim 1, wherein the drive circuit comprises:

a plurality of scan lines;

a plurality of data lines; and

plural thin film transistors, one of the plural thin firm transistors deposited in each pixel region of the liquid crystal display panel, the plural thin film transistors connected to the plural scan lines and the plural data lines.

12. The liquid crystal display panel of claim 1, further comprising:

a first and second crossed polarizer formed respectively on an exterior surface of the first and second substrates.

13. The liquid crystal display panel of claim 1, further comprising:

a color filter formed on the first substrate between the first substrate and the over-coating-layer.

14. A method of fabricating a liquid crystal display panel having plural pixel regions comprising the steps of:

providing a first substrate;

providing a second substrate;

forming an insulator layer on the interior surface of the second substrate;

forming a passivation layer on the insulating layer;

forming an over-coating layer on a portion of one of the first substrate and the passivation layer;

forming a common electrode on a corresponding one of the first substrate the over-coating layer;

forming a pixel electrode on the insulator layer;

forming a plurality of non aligned common domain guides and pixel domain guides respectively in the common electrode and the pixel electrode;

forming an electric shield adjacent to the over-coating layer on the corresponding one of the common electrode and pixel electrode;

sandwiching a vertically aligned liquid crystal layer between the first and second substrates; and

connecting a drive circuit with the common electrode and the pixel electrode for applying a voltage to the common electrode and the pixel electrode to generate an electric field between the first substrate and the second substrate to control a liquid crystal molecule orientation corresponding to a positioning of the plurality of common and pixel domain guides and plurality of electric shields to form a multi-domain vertically aligned liquid crystal display panel.

15. The method of claim 14, wherein connecting a drive circuit step comprises the step of:

fabricating a plurality of thin film transistors, plural scan lines and plural data lines on the interior surface of the second substrate, each thin film transistor located in one of plural pixel regions with the insulating layer covering the plurality of thin film transistors, plural scan lines and plural data lines; and

electrically connecting each one of the plural thin film transistors to one of the plural pixel electrodes, one of the plural data lines and one of the plural scan lines in each of the plural pixel regions.

16. The method of claim 14, wherein the varied thickness of the over-coating layer ranges between approximately 0 μ

m to approximately 50 μ

m.

17. The method of claim 14, wherein the area ratio of the electric shield corresponding to the liquid crystal display panel is greater than approximately 1:

1000.

18. The method of claim 14, wherein the pixel electrode is an electrically conductive material with high optical transparency selected from a group consisting of:

indium tin oxide (ITO), indium zinc oxide (IZO) and zinc oxide (ZnO).

19. The method of claim 14, wherein the forming plural domain guides comprises the step of:

forming a common domain guide protrusion and a pixel domain guide protrusion on each of the corresponding common electrode and pixel electrode.

20. The method of claim 19, wherein the common domain guide protrusion and a pixel domain guide protrusion are formed by depositing a material selected from a group consisting of an organic material and an inorganic material.

21. The method of claim 20, wherein the organic material is selected from a group consisting of a-Si:

C;

O and a-Si;

O;

F.

22. The method of claim 20, wherein the inorganic material is selected from a group consisting of silicon nitride (SiN_x) and silicon oxide (SiO₂).

23. The method of claim 14, wherein the forming plural domain guides comprises the step of:

forming a common domain guide slit and a pixel domain guide slit on each of the corresponding common electrode and pixel electrode.

24. The method of claim 14, further comprising:

forming a plurality of scanning lines and data lines on the second substrate;

to define a pixel electrode areas; and

forming a plurality of thin film transistors connected to the scanning lines and data lines in each pixel region.

25. The method of claim 14, wherein step of forming plural domain guides comprise:

forming a common domain guide in the common electrode in each pixel region of the liquid crystal display panel; and

forming a pixel domain guide in the pixel electrode in each pixel region of the liquid crystal display panel, the common domain guide above and on one side of the pixel domain guide.

26. The method of claim 14, wherein the common domain guide is formed above and on one side of the pixel domain guide and the electric shield is located above and on an opposite side of the pixel domain guide dividing the common electrode into a first, second and third common electrode to form the multi-domain liquid crystal display panel having eight domains in each pixel region.

27. The method of claim 14, wherein the common domain guide is located above and on one side of the pixel domain guide and the electric shield is located above and on an opposite side of the pixel domain guide dividing the common electrode into a first and a second common electrode to form the multi-domain liquid crystal display panel having six domains in each pixel region.

28. The method of claim 14, wherein the step of forming the common domain guide comprises the step of:

forming a first and a second common domain guide on opposite sides of the pixel domain guide dividing the common electrode into three common electrodes.

29. The method of claim 14, further comprising the step of:

layering a color filter on an interior surface of the first substrate between the first substrate and the over-coating layer.

30. A multi-domain vertical alignment liquid crystal display panel comprising:

a first substrate;

a common electrode disposed on the first substrate;

a first and a second common domain guide in the common electrode dividing the common electrode into a first, second and third common electrode;

a second substrate having an insulating layer on an interior surface facing the first substrate;

a passivation layer formed on the insulating layer;

an over coating formed over a portion of the passivation layer;

a pixel electrode formed on the other portion of the passivation layer, on the adjacent side of the over coating and on the exterior surface of the over coating;

a pixel domain guides formed in the pixel electrode not covering the over coating, the pixel domain guide located below and between the first and second common domain guides;

a pixel electric shield formed over the pixel electrode adjacent to the over coating layer and the pixel domain guide below one of the common domain guides to separate the pixel electrode into different regions;

a vertically aligned liquid crystal layer sandwiched between the first and second substrates; and

a drive circuit connected with the common electrode and the pixel electrode for applying a voltage to generate an electric field between the first substrate and the second substrate to control a liquid crystal molecule orientation corresponding to a positioning of the plurality of common and pixel domain guides and plurality of electric shields to form a multi-domain vertical aligned liquid crystal display panel having eight domains.

32. The liquid crystal display panel of claim 32, wherein the drive circuit comprises:

a plurality of scan lines;

a plurality of data lines; and

plural thin film transistors, one of the plural thin firm transistors deposited in each pixel region of the liquid crystal display panel, the plural thin film transistors connected to the plural scan lines and the plural data lines.

31. The multi-domain vertical alignment liquid crystal display panel claimed in claim 32 further comprising:

a color filter formed on the first substrate between the first substrate and the common electrode.

33. The liquid crystal display panel of claim 32, wherein each of said plural common and pixel domain guides is a protrusion on the common electrode and the pixel electrode extending into said liquid crystal layer to form the multi-domain liquid crystal display configuration.

34. The liquid crystal display panel of claim 32, wherein each of said plural domain guides and plixel guide is a slit formed in the common electrode and the pixel electrode to form the multi-domain liquid crystal configuration.

37. The liquid crystal display panel of claim 32, further comprising:

a first and second crossed polarizer formed respectively on an exterior surface of the first and second substrates.