Display device having improved alignment

1. A display device comprising:

a substrate comprising a pixel;

a scan line for supplying a scan signal to the pixel;

a data line for supplying a data signal to the pixel;

a first power line for supplying a first driving power source to the pixel;

a second power line for supplying a second driving power source to the pixel; and

a third power line for supplying a ground voltage to the pixel,

wherein the pixel comprises:

first and second electrodes spaced apart from each other on the substrate;

a plurality of light emitting elements, each of the light emitting elements having first and second end portions in a length direction thereof and being arranged between the first electrode and the second electrode; and

a first switch electrically connected between the third power line and the first electrode, the first switch configured to be turned on by a control signal.

2. The display device of claim 1 , wherein the pixel further comprises first and second conductive lines on the same plane as the first and second electrodes, the first and second conductive lines being spaced apart from each other, and

wherein, when viewed on a plane, the first conductive line and the second conductive line are between the first electrode and the second electrode.

3. The display device of claim 2 , wherein, when the first switch is turned on, an AC voltage having a level different from that of the second driving power source is applied to the second electrode.

4. The display device of claim 3 , wherein the pixel further comprises:

a control signal line configured to have the control signal applied thereto;

a second switch connected between the first conductive line and the third power line, the second switch configured to be turned on concurrently with the first switch by the control signal; and

a third switch connected between the second conductive line and the second power line, the third switch configured to be turned on concurrently with the first switch by the control signal.

5. The display device of claim 4 , wherein the first conductive line and the second conductive line are floating electrodes.

6. The display device of claim 5 , wherein the control signal line is in the same layer as the scan line.

7. The display device of claim 6 , wherein each of the first, second, and third switches comprises a thin film transistor.

8. The display device of claim 7 , wherein each of the first, second, and third switches comprises:

a gate electrode on the substrate, the gate electrode being integral with the control signal line;

an active pattern overlapping one region of the gate electrode; and

first and second terminals contacting both ends of the active pattern.

9. The display device of claim 8 , wherein the pixel further comprises a pixel circuit connected between the first power line and the first electrode or between the second power line and the second electrode, and

wherein the pixel circuit comprises a driving transistor for driving the light emitting elements and a switching transistor connected between the data line and the driving transistor.

10. The display device of claim 9 , wherein the driving transistor and the switching transistor comprise a transistor having the same type as the first, second, and third switches.

11. The display device of claim 10 , wherein, when the first, second, and third switches are concurrently turned on, the ground voltage is supplied to the first electrode and the AC voltage is applied to the second electrode such that an electric field is formed between the first electrode and the second electrode.

12. The display device of claim 10 , wherein, when the first, second, and third switches are concurrently turned off, the first driving power source is applied to the first electrode via the pixel circuit and the second driving power source is applied to the second electrode.

13. The display device of claim 10 , wherein the pixel circuit further comprises:

a first capacitor connected between a gate electrode of the driving transistor and the first power line; and

a second capacitor connected between the first electrode and the second power line.

14. The display device of claim 13 , wherein the first capacitor comprises:

a first lower electrode on the substrate;

a first upper electrode on the first lower electrode; and an interlayer insulating layer interposed between the first lower electrode and the first upper electrode,

wherein the second capacitor comprises:

a second lower electrode in the same layer as the first lower electrode;

a second upper electrode on the second lower electrode; and

the interlayer insulating layer interposed between the second lower electrode and the second upper electrode, and

wherein the first upper electrode and the second upper electrode are in the same layer.

15. The display device of claim 14 , wherein the first conductive line is electrically connected to the first electrode through a first bridge pattern, and

wherein the second conductive line is electrically connected to the second electrode through a second bridge pattern spaced apart from the first bridge pattern.

16. The display device of claim 15 , wherein the first bridge pattern and the second bridge pattern are in the same layer as the data line.

17. The display device of claim 16 , wherein, when the first switch is turned on, the ground voltage is applied to each of the first conductive line and the first electrode and the AC voltage is applied to each of the second conductive line and the second electrode such that an electric field is formed between the first electrode and the second electrode.

18. The display device of claim 17 , wherein the pixel further comprises:

a first shielding electrode line between the first electrode and the interlayer insulating layer;

a second shielding electrode line between the first conductive line and the interlayer insulating layer; and

a third shielding electrode line between the second conductive line and the interlayer insulating layer.

19. A display device of claim 1 , comprising:

a substrate comprising a pixel;

a scan line for supplying a scan signal to the pixel;

a data line for supplying a data signal to the pixel;

a first power line for supplying a first driving power source to the pixel;

a second power line for supplying a second driving power source to the pixel; and

a third power line for supplying a ground voltage to the pixel,

wherein the pixel comprises:

first and second electrodes spaced apart from each other on the substrate;

a plurality of light emitting elements, each of the light emitting elements having first and second end portions in a length direction thereof and being arranged between the first electrode and the second electrode;

a first switch electrically connected between the third power line and the first electrode, the first switch configured to be turned on by a control signal;

a first contact electrode electrically connecting any one of the first and second end portions of each of the light emitting elements to the first electrode; and

a second contact electrode electrically connecting the other of the first and second end portions of each of the light emitting elements to the second electrode.