TOUCH SCREEN DISPLAY AND METHOD OF OPERATING THE SAME

• US 20120162088A1
• Filed: 12/22/2010
• Published: 06/28/2012
• Est. Priority Date: 12/22/2010
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Polymer Vision B.V. (Wistron Corporation)
• Inventors: van Lieshout, Petrus Johannes Gerardus, Peeters, Bart
• Granted Patent: US 8,970,512 B2
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/04184 Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes

Abstract

A touch screen display device is described that includes a display panel, a display driver, a sensor circuit and a combination unit. The display panel has a plurality of display elements arranged between a first and a second electrode layer. The display driver is arranged for providing display signals comprising a common display signal and an input control signal to the display panel. The sensor circuit is arranged for providing a probe signal and a shield signal mutually having the same phase and frequency and for generating a touch signal in response to the output signal received from the first electrode layer. The combination unit provides a drive signal to the first electrode layer derived from the common display signal and the probe signal, and further provides an output control signal for the display panel from the input control signal and the shield signal.

Claims

1. A touch screen display device comprising:

a display panel comprising a plurality of display elements arranged between a first electrode layer and a second electrode layer having respective pixel electrodes for the display elements;

a display driver for providing display signals to the display panel, said display signals comprising;

a common display signal, and

an input control signal for controlling the display panel,

a sensor circuit for providing a probe signal and a shield signal that has the same phase and frequency as the probe signal, and for generating a touch signal in response to an output signal received from the first electrode layer; and

a combination unit for providing a drive signal to the first electrode layer derived from the common display signal and the probe signal, and for providing an output control signal for controlling the display panel from the input control signal and the shield signal.

2. The touch screen display device according to claim 1, wherein the display panel includes an active matrix layer for driving the pixel electrodes, wherein the input control signal is an input control signal for the active matrix layer, and wherein an output control signal for the active matrix layer is derived from the input control signal and the shield signal.

3. The touch screen display device according to claim 1, wherein the combination unit comprises a first multiplexer for deriving the drive signal by multiplexing the common display signal and the probe signal and a second multiplexer for deriving the output control signal by multiplexing the input control signal and the shield signal.

4. The touch screen display device according to claim 1, wherein the combination unit comprises a first superposition unit for deriving the drive signal by superposing the common display signal and the probe signal and a second superposition unit for deriving the output control signal by superposing the input control signal and the shield signal.

5. The touch screen display device according to claim 2, wherein the pixel electrodes are coupled to a first side of a respective storage capacitor, a second side of said storage capacitor being coupled to a storage line and wherein the control signal is a signal for driving the storage line.

6. The touch screen display device according to claim 1, wherein the display driver and the sensor circuit have small signal drivers for those signals that are combined by the combination unit and wherein the combination unit has a respective amplifier for amplification of the combined signals.

7. The touch screen display device according to claim 1, wherein the first electrode layer extends beyond the display area.

8. The touch screen display device according to claim 7, wherein the first electrode layer extends beyond the display area over an extension distance that is in a range between 5 to 30% of the size of the display area in the direction of the extension.

9. A method of driving a touch screen display device, the display device comprising a display panel comprising a plurality of display elements arranged between a first electrode layer and a second electrode layer having respective pixel electrodes for the display elements, the method comprising the steps of:

providing display signals for the display panel, comprising a common display signal and an input control signal for the display panel;

providing a probe signal and a shield signal that has the same phase and frequency as the probe signal;

generating a touch signal in response to an output signal received from the first electrode layer;

providing a drive signal to the first electrode layer derived from the common display signal and the probe signal, and

providing an output control signal for the display panel from the input control signal and the shield signal.

10. The method of claim 9 wherein the display panel includes an active matrix layer for driving the pixel electrodes, wherein the input control signal is an input control signal for the active matrix layer, and wherein an output control signal for the active matrix layer is derived from the input control signal and the shield signal.

11. The method of claim 9 wherein a first multiplexer, during the providing a drive signal step, derives the drive signal by multiplexing the common display signal and the probe signal, and wherein a second multiplexer, during the providing an output control signal step, derives the output control signal by multiplexing the input control signal and the shield signal.

12. The method of claim 9 wherein a first superposition unit, during the providing a drive signal step, derives the drive signal by superposing the common display signal and the probe signal, and wherein a second superposition unit, during the providing an output control signal step, derives the output control signal by superposing the input control signal and the shield signal.

13. The method claim 10, wherein the pixel electrodes are coupled to a first side of a respective storage capacitor, a second side of said storage capacitor being coupled to the storage line and wherein the control signal is a signal for driving the storage line.

14. The method of claim 9, wherein both a display driver that provides the display signals to the display panel, and a sensor circuit that provides the probe signal and shield signal, have small signal drivers for those signals that are combined, and

wherein a respective amplifier is provided for amplification of the combined signals.

15. The method of claim 9, wherein the first electrode layer extends beyond the display area.

16. The method of claim 15, wherein the first electrode layer extends beyond the display area over an extension distance that is in a range between 5 to 30% of the size of the display area in the direction of the extension.