Backlight unit in display device and liquid crystal display device therewith

• US 20050140848A1
• Filed: 09/29/2004
• Published: 06/30/2005
• Est. Priority Date: 12/29/2003
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Philips LCD Company Limited (LG Display Co., Ltd.)
• Inventors: Woo, Jong Hoon, Yoo, Jang Jin
• Granted Patent: US 7,505,024 B2
• Time in Patent Office: Days
• US Class Current: 349/64
• CPC Class Codes: G02B 6/0043 provided on the surface of the light guide
• CPC Class Codes: G02B 6/0055 Reflecting element, sheet or layer
• CPC Class Codes: G02B 6/0068 Arrangements of plural sources, e.g. multi-colour light sources
• CPC Class Codes: G02F 1/133622 Colour sequential illumination

Abstract

A backlight unit in a display device having a Divided Display Area Method (DDAM) of a Field Sequential (FS) driving method applied thereto is provided. The backlight unit includes first to (n)th light guiding plates for field sequential drive, and a plurality of light sources arranged at at least one side of the first to (n)th light guiding plates at certain intervals.

Claims

1. A backlight unit suitable for a display device, the backlight unit comprising:

first to (n)th light guiding plates for field sequential drive; and

a plurality of light sources arranged at at least one side of the first to (n)th light guiding plates at certain intervals.

2. The backlight unit as claimed in claim 1, further comprising:

a light source controller to control an operation of the light sources.

3. The backlight unit as claimed in claim 2, wherein the light source controller includes at least one PCB substrate or FPC having the light sources arranged thereon and positioned at the at least one side of the first to (n)th light guiding plates.

4. The backlight unit as claimed in claim 1, further comprising:

at least one reflective plate between two adjacent light guiding plates among the first to (n)th light guiding plates.

5. The backlight unit as claimed in claim 4, wherein at least one of the first to (n)th light guiding plates includes at least one polished surface.

6. The backlight unit as claimed in claim 4, further comprising:

light distributing means for evenly distributing a light from the first to (n)th light guiding plates.

7. The backlight unit as claimed in claim 6, wherein the light distributing means includes at least one diffuser plate or diffuser sheet.

8. The backlight unit as claimed in claim 6, wherein the light distributing means is disposed above the first to (n)th light guiding plates.

9. The backlight unit as claimed in claim 5, further comprising:

light distributing means for evenly distributing a light from the first to (n)th light guiding plates.

10. The backlight unit as claimed in claim 4, wherein the at least one reflective plate is a double-sided reflective plate.

11. The backlight unit as claimed in claim 4, wherein the at least one reflective plate includes two one-sided reflective plates.

12. The backlight unit as claimed in claim 1, wherein at least one of the first to (n)th light guiding plates includes at least one polished surface.

13. The backlight unit as claimed in claim 1, further comprising:

means for changing a refractive index of an area between at least two adjacent light guiding plates among the first to (n)th light guiding plates.

14. The backlight unit as claimed in claim 13, wherein the changing means includes one of the following:

a reflective adhesive tape, a reflective plate, and a polished surface.

15. The backlight unit as claimed in claim 1, further comprising:

light distributing means for evenly distributing a light from the first to (n)th light guiding plates.

16. The backlight unit as claimed in claim 1, wherein each of the light sources includes a light emitting portion and a body portion.

17. The backlight unit as claimed in claim 1, wherein the first to (n)th light guiding plates have a plurality of dot patterns printed on an underside surface thereof.

18. The backlight unit as claimed in claim 1, wherein the light sources include R (Red), G (Green), and B (Blue) LED lamps.

19. A display device comprising:

a backlight unit including;

first to (n)th light guiding plates for field sequential drive, and

a plurality of light sources arranged at at least one of side of the first to (n)th light guiding plates at certain intervals; and

a liquid crystal display panel for receiving a light from the backlight unit.

20. The display device as claimed in claim 19, wherein the liquid crystal display panel includes:

first and second glass substrates bonded together with a gap therebetween, the first and second glass substrates being arranged above the backlight unit, and

a liquid crystal layer filled between the first and second glass substrates.

21. The display device as claimed in claim 20, wherein the first glass substrate includes a plurality of gate lines arranged in one direction at regular intervals, a plurality of data lines arranged in a direction perpendicular to the gate lines at regular intervals to define pixel regions, a matrix of pixel electrodes in respective pixel regions each defined at a cross of the corresponding gate line and the corresponding data line, and a plurality of thin film transistors at each cross of the gate lines and the data lines, and

the second glass substrate includes a black matrix layer for shielding a light incident on regions excluding the pixel regions, and a common electrode on the second glass substrate inclusive of the black matrix layer.

22. The display device as claimed in claim 19, further comprising:

a light source controller to control an operation of the light sources.

23. The display device as claimed in claim 22, wherein the light source controller includes at least one PCB substrate or FPC having the light sources arranged thereon and positioned at the at least one side of the first to (n)th light guiding plates.

24. The display device as claimed in claim 19, wherein the backlight unit further comprises:

at least one reflective plate between two adjacent light guiding plates among the first to (n)th light guiding plates.

25. The display device as claimed in claim 24, wherein at least one of the first to (n)th light guiding plates includes at least one polished surface.

26. The display device as claimed in claim 24, further comprising:

light distributing means for evenly distributing a light from the first to (n)th light guiding plates.

27. The display device as claimed in claim 26, wherein the light distributing means includes at least one diffuser plate or diffuser sheet.

28. The display device as claimed in claim 26, wherein the light distributing means is disposed above the first to (n)th light guiding plates.

29. The display device as claimed in claim 25, further comprising:

light distributing means for evenly distributing a light from the first to (n)th light guiding plates.

30. The crystal display device as claimed in claim 24, wherein the at least one reflective plate is a double-sided reflective plate.

31. The display device as claimed in claim 24, wherein the at least one reflective plate includes two one-sided reflective plates.

32. The display device as claimed in claim 19, wherein at least one of the first to (n)th light guiding plates includes at least one polished surface.

33. The display device as claimed in claim 19, wherein the backlight unit further comprises:

means for changing a refractive index of an area between at least two adjacent light guiding plates among the first to (n)th light guiding plates.

34. The display device as claimed in claim 33, wherein the changing means includes one of the following:

a reflective adhesive tape, a reflective plate, and a polished surface.

35. The display device as claimed in claim 19, further comprising:

light distributing means for evenly distributing a light from the first to (n)th light guiding plates.

36. The display device as claimed in claim 19, wherein the first to (n)th light guiding plates have a plurality of dot patterns printed on an underside surface thereof.

37. The display device as claimed in claim 19, wherein the light sources include R (Red), G (Green), and B (Blue) LED lamps.