Display device and manufacturing method thereof

1. A display device comprising:

a first panel comprising a first lower substrate and a first upper substrate;

a first alignment key formed in the first lower substrate;

a second alignment key formed in the first upper substrate, the second alignment key is disposed in a position corresponding to the first alignment key;

a second panel attached to the first panel; and

a third alignment key formed in the second panel, the third alignment key is disposed in a position corresponding to the first and the second alignment keys and formed such that the first and the second alignment keys are identified.

2. The display device of claim 1 , wherein the first, second and third alignment keys have a cross shape.

3. The display device of claim 1 , wherein the first, second and third alignment keys are formed in a bezel region located around a display.

4. The display device of claim 1 , wherein the third alignment key comprises a transparent region through which predetermined portions of the first and second alignment keys are identified and an opaque region through which the remaining portions of the first and second alignment keys are not identified.

5. The display device of claim 4 , wherein the transparent region of the third alignment key is formed such that the edge of the first or second alignment key is identified.

6. The display device of claim 1 , wherein the first alignment key and the second alignment key respectively comprise a first sub-alignment key and a second sub-alignment key which are disposed in regions that are not identified by the third alignment key, and the first sub-alignment key and the second sub-alignment key are formed at positions corresponding to each other and located around the first alignment key and the second alignment key.

7. The display device of claim 6 , wherein size of the first and second sub-alignment keys are smaller than size of the first and second alignment keys.

8. The display device of claim 1 , wherein the second panel comprises a second lower substrate having a fourth alignment key and a second upper substrate having a fifth alignment key disposed in a position corresponding to the fourth alignment key, the second lower substrate and the second upper substrate are aligned with each other by the fourth alignment key and the fifth alignment key.

9. The display device of claim 8 , wherein the fourth and fifth alignment keys are formed in the bezel region located around the display area defined in the first and second panels such that the fourth and fifth alignment keys are distinguished from the first, second and third alignment keys.

10. The display device of claim 1 , wherein the second panel is a control panel that controls an image displayed on the first panel and displays the controlled image.

11. A method of manufacturing a display device, comprising:

forming a first alignment key formed in the first lower substrate;

forming a second alignment key formed in the first upper substrate, which is disposed in a position corresponding to the first alignment key;

aligning the first lower substrate and the first upper substrate using the first alignment key and the second alignment key;

attaching the first lower substrate and the first upper substrate to form a first panel;

forming a second panel;

forming a third alignment key formed in the second panel, which is disposed in a position corresponding to the first and the second alignment keys and formed such that the first and the second alignment keys are identified;

aligning the first panel and the second panel using the first, the second and the third alignment key; and

attaching the first panel and the second.

12. The method of claim 11 , wherein the first, second and third alignment keys have a cross shape.

13. The method of claim 11 , wherein the first, second and third alignment keys are formed in a bezel region located around a display.

14. The method of claim 11 , wherein the third alignment key comprises a transparent region through which predetermined portions of the first and second alignment keys are identified and an opaque region through which the remaining portions of the first and second alignment keys are not identified.

15. The method of claim 14 , wherein the transparent region of the third alignment key is formed such that the edge of the first or second alignment key is identified.

16. The method of claim 11 , wherein the first alignment key and the second alignment key respectively comprise a first sub-alignment key and a second sub-alignment key which are disposed in regions that are not identified by the third alignment key, and the first sub-alignment key and the second sub-alignment key are formed at positions corresponding to each other and located around the first alignment key and the second alignment key.

17. The method of claim 16 , wherein size of the first and second sub-alignment keys are smaller than size of the first and second alignment keys.

18. The method of claim 11 , wherein the second panel comprises a second lower substrate having a fourth alignment key and a second upper substrate having a fifth alignment key disposed in a position corresponding to the fourth alignment key, the second lower substrate and the second upper substrate are aligned with each other by the fourth alignment key and the fifth alignment key.

19. The method of claim 18 , wherein the fourth and fifth alignment keys are formed in the bezel region located around the display area defined in the first and second panels such that the fourth and fifth alignment keys are distinguished from the first, second and third alignment keys.

20. The method of claim 11 , wherein the second panel is a control panel that controls an image displayed on the first panel and displays the controlled image.