BACKLIGHT UNIT AND LIQUID CRYSTAL DISPLAY INCLUDING THE SAME

Abstract

A backlight unit using a microwave plasma ultraviolet lamp as a light source and a liquid crystal display including the backlight unit. The backlight unit for a liquid crystal display comprises a tube filled with discharge gas, a cavity resonator in which one end of the tube is inserted, a magnetron for generating microwaves and supplying the generated microwaves to the cavity resonator, a magnetron driver for driving the magnetron, and a phosphor layer for converting ultraviolet light generated in the tube into visible light.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the present invention can be understood in more detail from the following description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a schematic exploded perspective view of a direct type backlight unit and a liquid crystal display including the backlight unit according to an embodiment of the present invention;

FIG. 2 is a view schematically showing the constitution of a light source for use in a backlight unit according to an embodiment of the present invention;

FIG. 3 is a plan view of a backlight unit according to an embodiment of the present invention;

FIG. 4 is a sectional view of a backlight unit taken along line IV-IV of FIG. 3;

FIGS. 5 and 6 are sectional views of backlight units according to embodiments of the present invention;

FIG. 7 is a schematic exploded perspective view of an edge type backlight unit and a liquid crystal display including the backlight unit according to an embodiment of the present invention;

FIG. 8 is a plan view of a backlight unit according to an embodiment of the present invention;

FIG. 9 is a sectional view taken along line IX-IX of FIG. 8;

FIGS. 10-12 are sectional views of backlight units according to embodiments of the present invention; and

FIG. 13 is a plan view of a backlight unit according to an embodiment of the present invention.

Claims

1. A backlight unit for a liquid crystal display, comprising: at least one tube filled with discharge gas;a cavity resonator, wherein an end of the tube is inserted in the cavity resonator;a magnetron for generating microwaves and supplying the generated microwaves to the cavity resonator;a magnetron driver for driving the magnetron; anda phosphor layer for converting ultraviolet light generated in the tube into visible light.

2. The backlight unit as claimed in claim 1, further comprising a diffusion sheet disposed above the tube, wherein the phosphor layer is formed on a surface of the diffusion sheet.

3. The backlight unit as claimed in claim 2, further comprising a reflection sheet disposed below the tube, wherein the reflection sheet includes an ultraviolet ray reflection sheet.

4. The backlight unit as claimed in claim 1, wherein the phosphor layer is formed on one of an inner or outer surface of the tube.

5. The backlight unit as claimed in claim 1, further comprising a light guide plate, wherein: a side of the light guide plate is disposed adjacent to the tube, andthe phosphor layer is formed on the side of the light guide plate disposed adjacent to the tube.

6. The backlight unit as claimed in claim 1, further comprising a light guide plate, wherein: a side of the light guide plate is disposed adjacent to the tube, andthe phosphor layer is formed on an upper surface of the light guide plate.

7. The backlight unit as claimed in claim 6, further comprising a reflection sheet disposed below the light guide plate, wherein the reflection sheet includes an ultraviolet ray reflection sheet.

8. The backlight unit as claimed in claim 5, further comprising a tube reflection sheet disposed around the tube to reflect incident light to the light guide plate, wherein the tube reflection sheet includes an ultraviolet ray reflection sheet.

9. The backlight unit as claimed in claim 1, wherein the end of the tube is inserted in the cavity resonator at a depth of about 8 mm to about 12 mm.

10. The backlight unit as claimed in claim 1, wherein a tube mounting hole is formed on a side of the cavity resonator and the end of the tube is inserted in the tube mounting hole.

11. A liquid crystal display, comprising: a liquid crystal display panel;a backlight unit for providing visible light to the liquid crystal display panel; anda receiving case for receiving the backlight unit therein,wherein the backlight unit comprises: a tube filled with discharge gas;a cavity resonator, wherein an end of the tube is inserted into the cavity resonator;a magnetron for generating microwaves and supplying the generated microwaves to the cavity resonator;a magnetron driver for driving the magnetron; anda phosphor layer for converting ultraviolet light generated in the tube into visible light.

12. The liquid crystal display as claimed in claim 11, wherein the phosphor layer is formed on a surface of the receiving case.

13. The liquid crystal display as claimed in claim 11, wherein the magnetron driver is positioned on a surface of the receiving case.

14. The liquid crystal display as claimed in claim 11, further comprising a light guide plate, wherein a first side of the light guide plate is disposed adjacent to the tube and the magnetron driver is positioned in a space between a second side of the light guide plate adjacent to the first side and sides of the magnetron and cavity resonator.