Liquid crystal display having a field emission backlight

• US 20090185110A1
• Filed: 10/04/2006
• Published: 07/23/2009
• Est. Priority Date: 06/28/2006
• Status: Active Grant

• Current Assignee: InterDigital Madison Patent Holdings (InterDigital, Inc.)
• Original Assignee: Thomson Licensing (Vantiva SA)
• Inventors: Ritt, Peter Michael, Gorog, Istvan
• Granted Patent: US 8,259,258 B2
• Time in Patent Office: Days
• US Class Current: 349/71
• CPC Class Codes: G02F 1/133602 Direct backlight
• CPC Class Codes: G02F 1/133621 providing coloured light G02F1/133617, G02F1/133533 take precedence
• CPC Class Codes: G02F 1/133625 Electron stream lamps
• CPC Class Codes: H01J 63/04 Vessels provided with luminescent coatings; Selection of materials for the coatings
• CPC Class Codes: H01L 21/4814 Conductive parts

Abstract

An LCD display has a programmable back-light device that produces multiple different color fields from multiple different phosphor elements. The backlight device can be a low resolution FED device. The phosphor is applied by an electrophotographic screening process or direct electrostatic screening process. The FED device can further incorporate a wide gamut phosphor.

Claims

1. A liquid crystal display comprising:

a liquid crystal front end component and

a field emission backlight component, the field emission backlight component being low resolution.

2. The liquid crystal display of claim 1, wherein the field emission backlight component has a plurality of individual elements of phosphor.

3. The liquid crystal display of claim 2, wherein the plurality of individual elements are grouped into repeat units and the individual elements in the repeat units differ in color.

4. The liquid crystal display of claim 3, wherein the individual elements of the field emission backlight component are programmable and synchronized such that selected groups of the individual elements will activate in conjunction with activation of associated liquid crystal cells of the liquid crystal component.

5. The liquid crystal display of claim 2, wherein at least some of the individual elements comprise a water incompatible phosphor.

6. The liquid crystal display of claim 5, wherein one phosphor of the plurality of individual elements is strontium thiogallate:

europium.

7. The liquid crystal display of claim 2, wherein the individual elements of the field emission backlight component are programmable and synchronized such that selected groups of the individual elements will activate in conjunction with activation of associated liquid crystal cells of the liquid crystal component.

8. The liquid crystal display of claim 3, wherein at least some of the individual elements comprise a water incompatible phosphor.

9. The liquid crystal display of claim 8, wherein one phosphor of the plurality of individual elements is strontium thiogallate:

europium.

10. The liquid crystal display of claim 2, wherein the plurality of individual elements run in columns or rows.

11. The liquid crystal display of claim 10, wherein a ratio of individual columns or rows to the number of pixels lines is in the range of 1:

3-1000.

12. The liquid crystal display of claim 10, wherein a ratio of individual columns or rows to the number of pixels lines is in the range of 1:

100-1000.

13. The liquid crystal display of claim 11, wherein the individual elements of the field emission backlight component are programmable and synchronized such that selected groups of the individual elements will activate in conjunction with activation of associated liquid crystal cells of the liquid crystal component.

14. The liquid crystal display of claim 12, wherein the individual elements of the field emission backlight component are programmable and synchronized such that selected groups of the individual elements will activate in conjunction with activation of associated liquid crystal cells of the liquid crystal component.

15. The liquid crystal display of claim 3, wherein the field emission backlight component has 10 or more of the repeat units.

16. The liquid crystal display of claim 15, wherein the individual elements of the field emission backlight component are programmable and synchronized such that selected groups of the individual elements will activate in conjunction with activation of associated liquid crystal cells of the liquid crystal component.

17. The liquid crystal display of claim 2, wherein the field emission backlight component has a cathode comprising carbon nanotubes for emitting electrons which are to strike the phosphor of the plurality of individual elements.

18. The liquid crystal display of claim 17, wherein the plurality of individual elements are grouped into repeat units and the individual elements in the repeat units differ in color.

19. The liquid crystal display of claim 18, wherein the individual elements of the field emission backlight component are programmable and synchronized such that selected groups of the individual elements will activate in conjunction with activation of associated liquid crystal cells of the liquid crystal component.

20. The liquid crystal display of claim 19, wherein at least some of the individual elements comprise a water incompatible phosphor.

21. The liquid crystal display of claim 20, wherein one phosphor of the plurality of individual elements is strontium thiogallate:

europium.

22. The liquid crystal display of claim 21, wherein the field emission backlight component operates at 10-20 kV.

23. The liquid crystal display of claim 15, wherein the field emission backlight component operates at 10-20 kV.

24. The liquid crystal display of claim 11, wherein the field emission backlight component operates at 10-20 kV.

25. The liquid crystal display of claim 13, wherein an anode plate and a cathode plate of the field emission backlight component have a spacing of 1-5 mm.

26. The liquid crystal display of claim 14, wherein an anode plate and a cathode plate of the field emission backlight component have a spacing of 1-5 mm.

27. A display comprising:

a liquid crystal component and

a field emission component for producing a plurality of colors, the field emission component being low resolution.

28. The display of claim 27, wherein the field emission component has a plurality of individual elements of phosphor.

29. The liquid crystal display of claim 28, wherein the plurality of individual elements run in columns or rows.

30. The liquid crystal display of claim 29, wherein a ratio of individual columns or rows to the number of pixels lines is in the range of 1:

3-1000.

31. The liquid crystal display of claim 29, wherein a ratio of individual columns or rows to the number of pixels lines is in the range of 1:

100-1000.

32. The display of claim 27, wherein the field emission component is low resolution.