SURFACE LIGHT SOURCE DEVICE AND BACKLIGHT UNIT HAVING THE SAME

Abstract

There is provided a surface light source device, including: a light source body having a first substrate and a second substrate between which a plurality of discharge spaces are formed, a discharge gas being provided into the discharge spaces; a reflecting layer formed on an inner surface of the first substrate; a first adsorption preventing layer formed on the reflecting layer, for preventing the discharge gas from being adsorbed to the reflecting layer; a first fluorescent layer formed on the first adsorption preventing layer; a second fluorescent layer formed on an inner surface of the second substrate; and an electrode applying a discharge voltage to the discharge gas. Accordingly, since the discharge gas is uniformly distributed in the discharge spaces, the surface light source device has improved brightness uniformity.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features and advantages of the present invention will become more apparent to those of ordinary skill in the art by describing in detail preferred embodiments thereof with reference to the attached drawings in which:

FIG. 1 is a perspective view illustrating a surface light source device according to a first embodiment of the present invention;

FIG. 2 is a sectional view taken along Line II-II of FIG. 1;

FIG. 3 is a sectional view illustrating a surface light source device according to a second embodiment of the present invention;

FIG. 4 is an enlargement of Part IV of FIG. 3;

FIG. 5 is a perspective view illustrating a surface light source device according to a third embodiment of the present invention;

FIG. 6 is a sectional view taken along Line VI-VI of FIG. 5;

FIG. 7 is an exploded perspective view illustrating a backlight unit according to a fourth embodiment of the present invention;

FIG. 8A is a picture showing the initial brightness of a surface light source device according to a first experimental example;

FIG. 8B is a picture showing the initial brightness of a surface light source device according to a second experimental example;

FIG. 8C is a picture showing the initial brightness of a surface light source device according to a comparative example;

FIG. 9A is a picture showing the brightness of the surface light source device according to the first experimental example, after 100 hours;

FIG. 9B is a picture showing the brightness of the surface light source device according to the second experimental example, after 100 hours;

FIG. 9C is a picture showing the brightness of the surface light source device according to the comparative example, after 100 hours;

FIG. 10A is a picture showing the brightness of the surface light source device according to the first experimental example, after 200 hours;

FIG. 10B is a picture showing the brightness of the surface light source device according to the second experimental example, after 200 hours;

FIG. 10C is a picture showing the brightness of the surface light source device according to the comparative example, after 200 hours;

FIG. 11A is a picture showing the brightness of the surface light source device according to the first experimental example, after 300 hours;

FIG. 11B is a picture showing the brightness of the surface light source device according to the second experimental example, after 300 hours;

FIG. 11C is a picture showing the brightness of the surface light source device according to the comparative example, after 300 hours;

FIG. 12A is a picture showing the brightness of the surface light source device according to the first experimental example, after 500 hours;

FIG. 12B is a picture showing the brightness of the surface light source device according to the second experimental example, after 500 hours; and

FIG. 12C is a picture showing the brightness of the surface light source device according to the comparative example, after 500 hours.

Claims

1. A surface light source device, comprising: a light source body having a first substrate and a second substrate between which a plurality of discharge spaces are formed, a discharge gas being provided into the discharge spaces;a reflecting layer formed on an inner surface of the first substrate;a first adsorption preventing layer formed on the reflecting layer, for preventing the discharge gas from being adsorbed to the reflecting layer;a first fluorescent layer formed on the first adsorption preventing layer;a second fluorescent layer formed on an inner surface of the second substrate; andan electrode applying a discharge voltage to the discharge gas.

2. The surface light source device of claim 1, further comprising: a second adsorption preventing layer formed on the first fluorescent layer, for preventing the discharge gas from being adsorbed to the first fluorescent layer; anda third adsorption preventing layer formed on the second fluorescent layer, for preventing the discharge gas from being adsorbed to the second fluorescent layer.

3. The surface light source device of claim 2, wherein the second adsorption preventing layer has 20% or less thickness of a thickness of the first fluorescent layer.

4. The surface light source device of claim 2, wherein the second adsorption preventing layer is 10 nm to 10 μm in thickness.

5. The surface light source device of claim 2, wherein the first adsorption preventing layer has a greater thickness than the thickness of the second adsorption preventing layer.

6. The surface light source device of claim 2, wherein the first and second adsorption preventing layers are made of metal oxide.

7. The surface light source device of claim 6, wherein the metal oxide comprises at least any one selected from a group of alumina, zirconia, titania and yttria.

8. The surface light source device of claim 1, further comprising: an elution preventing layer interposed between the second substrate and the second fluorescent layer, for preventing a metal contained in the second substrate from being eluted to the second fluorescent layer.

9. A surface light source device comprising: a light source body having a first substrate and a second substrate between which a plurality of discharge spaces are formed, a discharge gas being provided into the discharge spaces;a reflecting layer formed on an inner surface of the first substrate;a compound fluorescent layer formed on at least any one of the reflecting layer and an inner surface of the second substrate, the compound fluorescent layer composed of a fluorescent substance and an adsorption preventing material; andan electrode applying a discharge voltage to the discharge gas.

10. A backlight unit comprising: a surface light source device, comprising a light source body having a first substrate and a second substrate between which a plurality of discharge spaces are formed, a discharge gas being provided into the discharge spaces, a reflecting layer formed on an inner surface of the first substrate, a first adsorption preventing layer formed on the reflecting layer, for preventing the discharge gas from being adsorbed to the reflecting layer, a first fluorescent layer formed on the first adsorption preventing layer, a second fluorescent layer formed on an inner surface of the second substrate, and an electrode applying a discharge voltage to the discharge gas;a case for receiving the surface light source device;an optical sheet interposed between the surface light source device and the case; andan inverter for supplying the discharge voltage for driving the surface light source device to the electrode.