Backlight device, display device with the same, and method of manufacturing the backlight device

1. A backlight device comprising:

a frame formed of a sheet material;

a first adhesive layer provided on one surface of the frame;

a reflective sheet attached to the frame with the first adhesive layer;

an optical member disposed on the reflective sheet in the frame; and

a light source disposed in the frame and configured to emit light to the optical member,

wherein in at least a part of the frame,

a width of the frame and a width of the first adhesive layer are equal to each other, and

at least an external surface of the frame and an external surface of the first adhesive layer are flush with each other.

2. The backlight device of claim 1 , wherein an external surface of the reflective sheet is flush with the external surfaces of the first adhesive layer and the frame.

3. The backlight device of claim 1 , wherein the frame has a thickness of 0.4 mm or less.

4. The backlight device of claim 1 , wherein the frame has a uniform thickness over a whole perimeter.

5. The backlight device of claim 1 , wherein the frame comprises bars, and in at least one of the bars, the width of the frame is 0.6 mm or less.

6. The backlight device of claim 5 , wherein

a width of each of the bars and the width of the first adhesive layer are equal to each other, and

an external surface and an internal surface of the bar are flush with the external surface and an internal surface of the first adhesive layer, respectively.

7. The backlight device of claim 1 , further comprising a second adhesive layer provided on an other surface opposed to the one surface,

wherein, in at least a part of the frame, the width of the frame and a width of the second adhesive layer are equal to each other, and

the external surface of the frame and an external surface of the second adhesive layer are flush with each other.

8. The backlight device of claim 1 , wherein the frame comprises at least four side portions,

a second adhesive layer is provided on an other surface opposed to the one surface, and

in three successive side portions of the frame,

the width of the frame and a width of the second adhesive layer are equal to each other, and

the external surface and an internal surface of the frame are flush with an external surface and an internal surface of the second adhesive layer, respectively.

9. The backlight device of claim 8 , wherein the optical member includes a lightguide plate provided on the reflective sheet and an optical sheet disposed on the lightguide plate, and

each of a sum of thicknesses of the lightguide plate and the optical sheet and a sum of thicknesses of the frame, the first adhesive layer, and the second adhesive layer is 0.36 to 0.52 mm.

10. The backlight device of claim 9 , wherein the optical sheet comprises a peripheral portion covering a gap between the lightguide plate and the frame, and

the peripheral portion is attached to the frame with the second adhesive layer.

11. The backlight device of claim 10 , wherein, the frame includes bars, the external surface of the one of the bars and an external surface of the optical sheet are flush with each other.

12. The backlight device of claim 11 , wherein a light-shielding resin layer covering the external surface of the optical sheet is provided.

13. The backlight device of claim 1 , wherein the sheet material is one of a resin sheet and a metal sheet.

14. A display device comprising:

a liquid crystal display panel; and

the backlight device of claim 1 , the backlight device being opposed to the liquid crystal display panel.

15. The display device of claim 14 , wherein the frame of the backlight device is attached to the liquid crystal display panel with a second adhesive layer.