Display device and driving method thereof

1. A display device comprising:

a flat display unit configured to output a planar image;

a hologram generation unit configured to output a hologram image;

a controller configured to acquire the holographic image with respect to the planar image;

an upper plate;

a lower plate separated and arranged having a predetermined space from the upper plate;

a connector configured to connect one side of the upper plate and to one side of the lower plate;

an image projector arranged at an end of the connector and configured to project the at least the portion of the planar image;

a mirror arranged on the upper plate and configured to reflect the planar image to the lower plate; and

a scanning screen arranged on the lower plate and configured to project the image reflected from the mirror to the predetermined space between the upper plate and the lower plate to display the holographic image,

wherein the scanning screen rotates about a rotation axis perpendicular to a surface of the lower plate,

wherein a protrusion is formed at one side of the upper plate and projected downward from the upper plate,

wherein the protrusion of the upper plate includes a first surface facing the image projector and a second surface opposite the first surface, and

wherein an angle θ 1 between the first surface of the protrusion and a lower surface of the upper plate differ from an angle θ 2 between the second surface of the protrusion and the lower surface of the upper plate.

2. The display device according to claim 1 , wherein the controller is configured to acquire depth information from the planar image and to obtain the holographic image with respect to the planar image on the basis of the acquired depth information.

3. The display device according to claim 2 , wherein the controller is configured to select a specific image object included in the planar image and to acquire a holographic image of the selected image object on the basis of depth information of the selected image object.

4. The display device according to claim 3 , wherein the controller is configured to select the specific image object from among image objects included in the planar image on the basis of depth information of the image objects included in the planar image.

5. The display device according to claim 3 , wherein the controller is configured to select the specific image object from among image objects included in the planar image on the basis of a gesture of a user, a gaze of the user, operation of a remote controller by the user, or touch of the user through the flat display unit including a touchscreen function.

6. The display device according to claim 3 , wherein the controller is configured to select the specific image object from among image objects included in the planar image on the basis of additional information about the image objects included in the planar image.

7. The display device according to claim 1 , wherein the hologram generation unit comprises:

an image generation unit configured to generate the planar image;

a first mirror configured to reflect the generated planar image; and

a second mirror configured to reflect the image reflected by the first mirror to a front space of the flat display unit to display the holographic image.

8. The display device according to claim 1 , wherein the controller is configured to activate rotation of the scanning screen to output the holographic image upon determining that the upper plate and the lower plate are parallel with each other.

9. The display device according to claim 1 , wherein the controller is configured to deactivate rotation of the scanning screen to output the planar image upon determining that the upper plate and the lower plate are not parallel with each other.

10. The display device according to claim 1 , further comprising:

a light source provided on the protrusion and maintaining a predetermined angle to the downward direction,

wherein the controller is configured to activate the light source upon determining that an illumination request signal is received.