Foldable display device

1. A foldable display device comprising:

a housing which comprises a folding area, a first unfolding area adjacent to the folding area, and a second unfolding area adjacent to the folding area and under the first unfolding area;

a display panel located at the first unfolding area and the second unfolding area and capable of providing light through a first surface and a second surface opposite the first surface;

a shutter layer on the display panel in the first unfolding area that controls whether light is transmitted;

a window on the shutter layer; and

a shielding layer located at the second unfolding area, the shielding layer being configured to block a light provided through the second surface of the display panel completely,

wherein the shielding layer is formed continuously to cover a plurality of pixels of the display panel located at the second unfolding area, and

wherein the shielding layer continuously extends from the second unfolding area through the folding area and does not extend into the first unfolding area.

2. The foldable display device of claim 1 , wherein the first surface of the display panel located at the first unfolding area faces the first surface of the display panel located at the second unfolding area, and the second surface of the display panel located at the first unfolding area is under the shutter layer.

3. The foldable display device of claim 2 , wherein the shielding layer is under the second surface of the display panel disposed in the second unfolding area.

4. A foldable display device comprising:

a housing which comprises a folding area, a first unfolding area adjacent to the folding area, and a second unfolding area adjacent to the folding area and under the first unfolding area;

a display panel located at the first unfolding area and the second unfolding area and capable of providing light through a first surface and a second surface opposite the first surface;

a shutter layer on the display panel in the first unfolding area that controls whether light is transmitted;

a window on the shutter layer;

a shielding layer located at the second unfolding area that is capable of blocking the light; and

a controller that controls the operation of the shutter layer and the display panel according to a mode, wherein the controller, in a folding mode in which the folding area is folded, controls at least one of the display panel located at the first unfolding area and the display panel located at the second unfolding area to provide the light and controls the shutter layer to transmit the light and, in an unfolding mode in which the folding area is not folded, controls both the display panel located at the first unfolding area and the display panel located at the second unfolding area to provide the light and controls the shutter layer not to transmit the light.

5. The foldable display device of claim 4 , wherein, in the folding mode, the controller controls any one of the display panel located at the first unfolding area and the display panel located at the second unfolding area to provide the light and controls the other display panel not to provide the light.

6. The foldable display device of claim 5 , wherein the display panel comprises a plurality of pixel regions, and the controlling of the any one of the display panel located at the first unfolding area and the display panel located at the second unfolding area to provide the light and the controlling of the other display panel not to provide the light by the controller comprises controlling all of a plurality of pixel regions included in the any one of the display panel located at the first unfolding area and the display panel located at the second unfolding area to provide the light and controlling all of a plurality of pixel regions included in the other display panel not to provide the light.

7. The foldable display device of claim 4 , wherein, in the unfolding mode, the controller controls both the display panel located at the first unfolding area and the display panel located at the second unfolding area to provide the light.

8. The foldable display panel of claim 4 , wherein the display panel comprises an organic light emitting display panel having an organic light emitting element, and the controlling of the display panel not to provide the light by the controller comprises not providing a driving current to the organic light emitting element.

9. The foldable display device of claim 1 , further comprising:

an illuminance sensor that senses external illuminance; and

a controller that controls the display panel located at the first unfolding area and the display panel located at the second unfolding area to provide or not to provide the light using the sensing result of the illuminance sensor.

10. The foldable display device of claim 9 , wherein the controller, when the sensing result is a first result, controls any one of the display panel located at the first unfolding area and the display panel located at the second unfolding area to provide the light and controls the other display panel not to provide the light and, when the sensing result is a second result different from the first result, controls both the display panel located at the first unfolding area and the display panel located at the second unfolding area to provide the light.

11. A foldable display device comprising:

a housing comprising a first area and a second area horizontally adjacent to each other;

a display panel located over the first area and the second area and capable of providing light through a first surface and a second surface opposite the first surface;

a shutter layer on the second surface of the display panel in the first area that controls whether to transmit the light;

a shielding layer on the second surface of the display panel in the second area, the shielding layer being configured to block a light provided through the second surface of the display panel completely;

a window located at the first area and not the second area; and

wherein the shielding layer is formed continuously to cover a plurality of pixels of the display panel located at the second unfolding area, and

wherein the shielding layer extends continuously through the second area and does not extend into the first area.

12. The foldable display device of claim 11 , wherein the second area comprises a folding area in which the housing and the display panel are folded and an unfolding area in which the housing and the display panel are not folded.

13. The foldable display device of claim 12 , wherein, in a folding mode, the first surface of the display panel located at the unfolding area faces the first surface of the display panel located at the first area.

14. The foldable display device of claim 12 , further comprising a controller that controls the operation of the shutter layer according to mode, wherein the controller, in an unfolding mode in which the folding area is not folded, controls the shutter layer not to transmit the light and, in the folding mode in which the folding area is folded, controls the shutter layer to transmit the light.

15. The foldable display device of claim 11 , wherein the shutter layer is located at the first area and not the second area.

16. The foldable display device of claim 15 , wherein the shutter layer is between the window and the display panel.

17. The foldable display device of claim 15 , wherein the second area comprises a folding area in which the housing and the display panel are folded and an unfolding area in which the housing and the display panel are not folded, and the shielding layer is over the folding area and the unfolding area.

18. The foldable display device of claim 11 , wherein the display panel comprises an organic light emitting display panel comprising an organic light emitting element, a driving transistor for driving the organic light emitting element, and an encapsulation layer for protecting the organic light emitting element, wherein the driving transistor is located closer to the second surface of the display panel than the encapsulation layer.