Smartphone

1. A touch input device capable of detecting a pressure of a touch on a touch surface, the touch input device comprising:

a substrate; and

a display module;

wherein a reference potential layer is disposed within the display module;

wherein the touch input device further comprises an electrode which is disposed at a position where a distance between the electrode and the reference potential layer changes according to the touch on the touch surface;

wherein the distance changes according to a magnitude of the pressure of the touch;

wherein an electric signal depending on the distance is outputted from the electrode; and

wherein the pressure of the touch is detected based on the electrical signal which is changed according to the distance between the electrode which is disposed under the display module and the reference potential layer which is disposed within the display module.

2. The touch input device of claim 1 , wherein a spacer layer is located between the reference potential layer and the electrode.

3. The touch input device of claim 2 , wherein the electrode comprises a first electrode and a second electrode, and wherein a capacitance between the first electrode and the second electrode changes according to the distance.

4. The touch input device of claim 3 , wherein the first electrode and the second electrode are formed on the substrate, or the first electrode and the second electrode are formed on the display module, or one of the first electrode and the second electrode are formed on the substrate and the other is formed on the display module.

5. The touch input device of claim 2 , wherein the electrode is formed on the substrate.

6. The touch input device of claim 5 , wherein a capacitance between the electrode and the reference potential layer changes according to the distance.

7. The touch input device of claim 2 , wherein the electrode is formed on the display module.

8. The touch input device of claim 7 , wherein a capacitance between the electrode and the reference potential layer changes according to the distance.

9. The touch input device of claim 2 , wherein the electrode is located on an insulation layer located on either the substrate or on the display module.

10. The touch input device of claim 9 , wherein the electrode located on the insulation layer is covered with an additional insulation layer.

11. The touch input device of claim 9 , wherein the insulation layer and the electrode located on the insulation layer are formed as a sheet of an integral form and are attachable to the substrate or the display module.

12. The touch input device of claim 11 , wherein the electrode constitutes a plurality of channels.

13. The touch input device of claim 12 , wherein each pressure of a plurality of touches based on multi-touch is detected by the plurality of the channels.

14. The touch input device of claim 2 , wherein the electrode is formed by positioning a mask which has a through-hole corresponding to a pattern of the electrode and then by spraying a conductive material.

15. The touch input device of claim 2 , wherein the display module is bent in accordance with the touch on the touch surface.

16. The touch input device of claim 2 , further comprising:

a touch sensor panel capable of detecting a position of the touch on the touch surface; and

a first printed circuit board on which a touch sensing circuit for the operation of the touch sensor panel is mounted;

wherein the touch sensor panel is attached to the display module in such a manner as to be disposed on a side opposite to the substrate.

17. The touch input device of claim 16 ,

wherein the display module further comprises a second printed circuit board on which a control circuit for the operation of a display panel is mounted, wherein the electrode is printed on the second printed circuit board;

wherein the electrode is formed on an additional circuit board;

wherein the touch input device further comprises a connector between the additional circuit board and the first printed circuit board; and

wherein the electrode is electrically connected to the touch sensing circuit through the connector.

18. The touch input device of claim 16 ,

wherein the display module further comprises a second printed circuit board on which a control circuit for the operation of a display panel is mounted, wherein the electrode is printed on the second printed circuit board;

wherein the electrode is formed on an additional circuit board;

wherein the touch input device further comprises:

a first connector between the first printed circuit board and the second printed circuit board;

a second connector between the second printed circuit board and a main board on which a central processing unit (CPU) for the operation of the touch input device is mounted; and

a third connector between the additional circuit board and the main board; and

wherein the electrode is electrically connected to the touch sensing circuit through the first connector, the second connector, and the third connector.

19. The touch input device of claim 2 , wherein the display module further comprises a second printed circuit board on which a control circuit for the operation of a display panel is mounted, wherein the electrode is printed on the second printed circuit board.

20. The touch input device of claim 19 , further comprising:

a touch sensor panel capable of detecting a position of the touch on the touch surface; and

a first printed circuit board on which a touch sensing circuit for the operation of the touch sensor panel is mounted;

wherein the touch sensor panel is attached to the display module in such a manner as to be disposed on a side opposite to the substrate;

wherein the touch input device further comprises a connector between the first printed circuit board and the second printed circuit board; and

wherein the electrode is electrically connected to the touch sensing circuit through the connector.

21. The touch input device of claim 2 , wherein the display module further comprises a second printed circuit board on which a control circuit for the operation of a display panel is mounted, wherein the electrode is attached to the display module in such a manner as to be electrically connected to a conductive pattern printed on the second printed circuit board.

22. The touch input device of claim 21 , further comprising:

a touch sensor panel capable of detecting a position of the touch on the touch surface; and

a first printed circuit board on which a touch sensing circuit for the operation of the touch sensor panel is mounted;

wherein the touch sensor panel is attached to the display module in such a manner as to be disposed on a side opposite to the substrate;

wherein the touch input device further comprises a connector between the first printed circuit board and the second printed circuit board; and

wherein the electrode is electrically connected to the touch sensing circuit through the connector.

23. The touch input device of claim 1 , wherein the electrode constitutes a plurality of channels.

24. The touch input device of claim 23 , wherein each pressure of a plurality of touches based on multi-touch is detected by the plurality of the channels.