LCDS with integrated touch panels

• US 20080129898A1
• Filed: 10/19/2007
• Published: 06/05/2008
• Est. Priority Date: 11/09/2006
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: MOON, Seung-hwan
• Granted Patent: US 8,493,518 B2
• Time in Patent Office: Days
• US Class Current: 349/12
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/0418 for error correction or compensation, e.g. based on parallax, calibration or alignment
• CPC Class Codes: G06F 3/047 using sets of wires, e.g. crossed wires

Abstract

An LCD with an integrated touch panel that prevents sensor malfunction by eliminating coupling noises includes an insulating substrate, a plurality of gate lines formed on the insulating substrate so as to extend in a first direction, a plurality of data lines formed in a second direction so as to intersect the plurality of gate lines, a plurality of thin film transistors (TFTs), each formed at an area defined by the gate lines and the data lines, a plurality of sensor lines formed in the same directions as the gate lines and the data lines, and a plurality of dummy lines formed in the same directions as the sensor lines.

Claims

1. An LCD with an integrated touch panel, comprising:

an insulating substrate;

a plurality of gate lines formed on the insulating substrate so as to extend in a first direction and a plurality of data lines formed in a second direction so as to intersect the gate lines;

a plurality of thin film transistors (TFTs), each formed at an area defined by the gate lines and the data lines;

a plurality of sensor lines formed in the same directions as the gate lines and data lines; and

,

a plurality of dummy lines formed in the same directions as the sensor lines.

2. The LCD of claim 1, wherein the plurality of sensor lines includes first and second sensor lines formed in the first and second directions and the plurality of dummy lines include first and second dummy lines formed in the same directions as the first and second sensor lines, respectively.

3. The LCD of claim 2, wherein a reference voltage is applied to the dummy lines.

4. The LCD of claim 2, further comprising:

a first comparator connected to the first sensor line and the first dummy line and amplifying a voltage difference between the first sensor line and the first dummy line and then outputting the an amplified voltage difference; and

,

a second comparator connected to the second sensor line and the second dummy line and amplifying a voltage difference between the second sensor line and the second dummy line and then outputting the amplified voltage difference.

5. The LCD of claim 2, wherein the first sensor line and the second sensor line are connected to first and second electrodes, respectively, and wherein a common voltage is applied to the first sensor line and the second sensor line through the first and second electrodes when an external pressure is applied to the touch panel in the vicinity of the electrodes.

6. The LCD of claim 2, wherein the first sensor line and the first dummy line are formed in the same layer as the gate lines.

7. The LCD of claim 2, wherein the second sensor line and the second dummy line are formed in the same layer as the data lines.

8. The LCD of claim 1, wherein the plurality of sensor lines includes first and second sensor lines formed in the first and second directions, respectively, and the plurality of dummy lines includes a first dummy line formed along the periphery of the insulating substrate and second and third dummy lines formed in the first and second directions, respectively, the first dummy line being connected to the second and third dummy lines.

9. The LCD of claim 8, wherein a reference voltage is applied to the first through third dummy lines.

10. The LCD of claim 8, further comprising:

a first comparator connected to the first sensor line and the second dummy line and amplifying a voltage difference between the first sensor line and the second dummy line and then outputting the amplified voltage difference; and

,

a second comparator connected to the second sensor line and the third dummy line and amplifying a voltage difference between the second sensor line and the third dummy line and then outputting an amplified voltage difference.

11. The LCD of claim 8, wherein an initial voltage applied to the sensor lines is applied to the first through third dummy lines.

12. The LCD of claim 11, wherein the initial voltage is lower than a common voltage.

13. The LCD of claim 10, further comprising:

a third comparator connected to the output port of the first comparator and a fourth dummy line and amplifying a voltage difference between the output port of the first comparator and the fourth dummy line and then outputting the amplified voltage difference; and

,

a fourth comparator connected to the output port of the second comparator and a fifth dummy line and amplifying a voltage difference between the output port of the second comparator and the fifth dummy line and then outputting the amplified voltage difference.

14. The LCD of claim 13, wherein a reference voltage is applied to the third and fourth dummy lines.

15. An LCD with an integrated a touch panel, comprising:

a thin film transistor (TFT) array panel, including a plurality of gate lines formed on an insulating substrate so as to extend in a first direction and a plurality of data lines formed in a second direction so as to intersect the gate lines, a plurality of thin film transistors (TFTs), each formed at an area defined by the gate lines and the data lines, a plurality of sensor lines formed in the same directions as the gate lines and the data lines, and a plurality of dummy lines formed in the same directions as the sensor lines; and

,

a printed circuit board, including a first interconnection line for applying a predetermined voltage to the dummy lines, a second interconnection line for applying a gate-off voltage in the gate driver connected to the plurality of gate lines, and a capacitor coupled between the first and second interconnection lines for eliminating coupling noises.

16. The LCD of claim 15, wherein the plurality of sensor lines includes first and second sensor lines formed in first and second directions, respectively, and the plurality of dummy lines includes first and second dummy lines formed in the first and second directions, respectively, and a third dummy line connected to the first and second dummy lines, respectively.

17. The LCD of claim 16, further comprising:

a first comparator connected to the first sensor line and the first dummy line and amplifying a voltage difference between the first sensor line and the first dummy line and then outputting the amplified voltage difference; and

,

a second comparator connected to the second sensor line and the second dummy line and amplifying a voltage difference between the second sensor line and the second dummy line and then outputting an amplified voltage difference.

18. The LCD of claim 16, wherein the first sensor line and the second sensor line are connected to first and second electrodes, respectively, and wherein a common voltage is applied to the first sensor line and the second sensor line through the first and second electrodes when an external pressure is applied to the touch panel in the vicinity of the electrodes.

19. The LCD of claim 16, wherein the first sensor line and the first dummy line are formed in the same layer as the gate lines.

20. The LCD of claim 16, wherein the second sensor line and the second dummy line are formed in the same layer as the data lines.

21. The LCD of claim 15, wherein the predetermined voltage is a reference voltage or an initial voltage applied to the sensor lines.