Backlight unit and display device

1. A backlight unit comprising:

a printed circuit substrate;

a plurality of light sources disposed on the printed circuit substrate;

a reflective layer disposed on at least a partial area of an area in which the plurality of light sources are not disposed on the printed circuit substrate;

a color conversion light guide layer disposed on the plurality of light sources;

a transparent film disposed on the color conversion light guide layer and spaced apart from the plurality of light sources and the reflective layer;

a plurality of light diffusion patterns disposed on at least one of a top or bottom of the transparent film, and corresponding to each of the plurality of light sources; and

a non-color conversion light guide layer disposed on a top surface of the color conversion light guide layer that is disposed on the plurality of light sources,

wherein the color conversion light guide layer covers the plurality of light sources and comprises a resin having a third refractive index, and

the non-color conversion light guide layer is disposed on the color light guide layer, and comprises a resin having a fourth refractive index greater than the third refractive index.

2. A backlight unit comprising:

a printed circuit substrate;

a plurality of light sources disposed on the printed circuit substrate;

a reflective layer disposed on at least a partial area of an area in which the plurality of light sources are not disposed on the printed circuit substrate;

a color conversion light guide layer disposed on the plurality of light sources;

a transparent film disposed on the color conversion light guide layer and spaced apart from the plurality of light sources and the reflective layer;

a plurality of light diffusion patterns disposed on at least one of a top or bottom of the transparent film, and corresponding to each of the plurality of light sources; and

a non-color conversion light guide layer disposed on a bottom surface of the color conversion light guide layer that is disposed on the plurality of light sources,

wherein the color conversion light guide layer comprises a resin having a first refractive index, and

wherein the non-color conversion light guide layer comprises a resin having a second refractive index smaller than the first refractive index.

3. The backlight unit of claim 2 , wherein at least a portion of the light emitted from the plurality of light sources is totally reflected at an interface between the color conversion light guide layer and the non-color conversion light guide layer.

4. The backlight unit of claim 2 ,

wherein the transparent film is disposed on the non-color conversion light guide layer.

5. The backlight unit of claim 2 , wherein the plurality of light sources on the printed circuit substrate are disposed in a flip-chip structure,

the non-color conversion light guide layer covers the plurality of light sources, and

the color conversion light guide layer is disposed on the top surface of the non-color conversion light guide layer.

6. The backlight unit of claim 2 , wherein a thickness of the color conversion light guide layer is greater than a thickness of the non-color conversion light guide layer.

7. The backlight unit of claim 2 , wherein one of the color conversion light guide layer and the non-color conversion light guide layer is spaced apart from the plurality of light sources and the reflective layer.

8. The backlight unit of claim 2 , wherein the color conversion light guide layer comprises a plurality of color conversion phosphors mixed with the resin.

9. A display device comprising:

a display panel; and

a backlight unit to supply light to the display panel,

wherein the backlight unit comprises:

a printed circuit substrate;

a plurality of light sources disposed on the printed circuit substrate;

a reflective layer disposed on at least a partial area of an area in which the plurality of light sources are not disposed on the printed circuit substrate;

a color conversion light guide layer disposed on the plurality of light sources;

a transparent film disposed on the color conversion light guide layer and spaced apart from the plurality of light sources and the reflective layer;

a plurality of light diffusion patterns disposed on at least one of a top or bottom of the transparent film and corresponding to each of the plurality of light sources; and

a non-color conversion light guide layer disposed on at least one of a top surface or a bottom surface of the color conversion light guide layer that is disposed on the plurality of light sources,

wherein the color conversion light guide layer covers the plurality of light sources and comprises a resin having a third refractive index, and

the non-color conversion light guide layer comprises a resin having a fourth refractive index greater than the third refractive index.

10. A display device comprising:

a display panel; and

a backlight unit to supply light to the display panel,

wherein the backlight unit comprises:

a printed circuit substrate;

a plurality of light sources disposed on the printed circuit substrate;

a reflective layer disposed on at least a partial area of an area in which the plurality of light sources are not disposed on the printed circuit substrate;

a color conversion light guide layer disposed on the plurality of light sources;

a transparent film disposed on the color conversion light guide layer and spaced apart from the plurality of light sources and the reflective layer;

a plurality of light diffusion patterns disposed on at least one of a top or bottom of the transparent film and corresponding to each of the plurality of light sources; and

a non-color conversion light guide layer disposed on a bottom surface of the color conversion light guide layer that is disposed on the plurality of light sources,

wherein the color conversion light guide layer comprises a resin having a first refractive index, and

wherein the non-color conversion light guide layer comprises a resin having a second refractive index smaller than the first refractive index.

11. The display device of claim 10 ,

wherein the_transparent film is disposed on the color conversion light guide layer and the non-color conversion light guide layer, and is spaced apart from the plurality of light sources and the reflective layer.

12. The display device of claim 10 , wherein at least a portion of the light emitted from the plurality of light sources is totally reflected at an interface between the color conversion light guide layer and the non-color conversion light guide layer.

13. The display device of claim 10 ,

wherein the non-color conversion light guide layer covers the plurality of light sources and is located below the color light guide layer.

14. The display device of claim 10 , wherein the plurality of light sources on the printed circuit substrate are disposed in a flip-chip structure,

the non-color conversion light guide layer covers the plurality of light sources, and

the color conversion light guide layer is disposed on the top surface of the non-color conversion light guide layer.

15. The display device of claim 10 , wherein a thickness of the color conversion light guide layer is greater than a thickness of the non-color conversion light guide layer.

16. The display device of claim 10 , wherein the color conversion light guide layer comprises the resin mixed with a plurality of color conversion phosphors.

17. The display device of claim 10 , wherein one of the color conversion light guide layer and the non-color conversion light guide layer is spaced apart from the plurality of light sources and the reflective layer.