TOUCH DISPLAY CAPABLE OF ELIMINATING TOUCH IMPACT ON DISPLAY

• US 20120162134A1
• Filed: 03/09/2012
• Published: 06/28/2012
• Est. Priority Date: 09/27/2009
• Status: Abandoned Application

• Current Assignee: Inferpoint Systems Limited
• Original Assignee: Inferpoint Systems Limited
• Inventors: CHEN, Qiliang, LIU, Haiping, LI, Dehai
• Application Number:
  US13/416,714
• Publication Number:
  US 20120162134A1
• Time in Patent Office: Days
• US Class Current: 345/174
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence

Abstract

A touch display includes an active display screen, a display driving circuit, a touch system circuit, and a display/touch signal gating-switch and output circuit or display/touch signal loading and merge circuit. A vertical blanking time exists between each two display times of a display screen electrode, during the time, the display screen does not execute display driving, and stops scanning the row electrodes, the column electrodes and the COM electrode maintain an original output state or a certain preset output signal, and a part or all of active devices of the display screen are in an off state; during a time of transmitting a display signal by the display screen electrode, due to a transient potential difference of an applied touch signal between the electrodes, the active devices of the display screen are enabled to maintain the off state.

Claims

1. A touch display capable of eliminating a touch impact on display, comprising an active display screen, a display driving circuit, a touch system circuit, and a display/touch signal gating-switch and output circuit or display/touch signal loading and merge circuit capable of enabling a display screen electrode to be used for both display driving and touch detection;

wherein the touch system circuit has a touch excitation source and a touch signal detection unit;

the display/touch signal gating-switch and output circuit enables the display screen electrode to communicate with the display driving circuit to transmit a display driving signal, or to communicate with the touch system circuit to transmit a touch signal, and the display driving and the touch detection time division multiplex the display screen electrode;

the display/touch signal loading and merge circuit enables the display screen electrode to simultaneously transmit the display driving signal and the touch signal, and the display driving and the touch detection simultaneously share the display screen electrode;

one substrate of the display screen has an active device array and a row electrode group and a column electrode group connected to the active device array, and the other substrate of the display screen has a common (COM) electrode;

during a time of transmitting a display signal by the display screen electrode, the display driving circuit sequentially scans the row electrodes of the display screen, and the column electrodes and the COM electrode of the display screen cooperate to output the corresponding display signal;

a vertical blanking time exists between each two display times, during the time, the display screen does not execute the display driving, and stops scanning the row electrodes, the display driving circuit outputs non-selected signals for all the row electrodes, the column electrodes and the COM electrode maintain an original output state or a certain preset output signal, and a part or all of active devices of the display screen are in an off state;

wherein during the time of transmitting the display signal by the display screen electrode, due to a transient potential difference of the applied touch signal between the electrodes, the active devices of the display screen are enabled to maintain the off state, and an impact of the touch signal on display is eliminated.

2. The touch display according to claim 1, wherein

the enabling a part of the active devices of the display screen to be in the off state means enabling the active devices directly connected to a display pixel of the display screen to maintain the off state.

3. The touch display according to claim 1, wherein

due to the transient potential difference of the applied touch signal between electrode lines of the row electrode group and the column electrode group connected to the active device array, all or a part of the active devices of the display screen maintain the off state, and the impact of the touch signal on display is eliminated.

4. The touch display according to claim 1, wherein

due to the transient potential difference of the applied touch signal between a part of electrode lines of the row electrode group or the column electrode group connected to the active device array and the COM electrode, the active devices connected to the part of the electrode lines maintain the off state, and the impact of the touch signal on display is eliminated.

5. The touch display according to claim 1, wherein

the active device array on the substrate of the display screen is a Thin Film Transistor (TFT) array, row and column electrode lines are respectively connected to gates and sources of TFTs, or respectively connected to the gates and drains of the TFTs, and due to the transient potential difference of the applied touch signal between electrode lines of the row electrode group and the column electrode group connected to the TFT array, all or a part of the TFTs of the display screen maintain the off state.

6. The touch display according to claim 1, wherein

the active device array on the substrate of the display screen is a TFT array, row and column electrode lines are respectively connected to gates and sources of TFTs, or respectively connected to the gates and drains of the TFTs, and due to the transient potential difference of the applied touch signal between electrode lines connected to the gates of the TFTs in the row electrode lines or the column electrode lines and the COM electrode, all or a part of the active devices of the display screen maintain the off state.

7. The touch display according to claim 1, wherein

in terms of a touch signal relation between the electrodes to which the touch signal is applied, an average value of the potential difference between the electrodes remains unchanged, so as to avoid a perceptible change in display effect.

8. The touch display according to claim 6, wherein

in terms of a touch signal relation between the electrodes to which the touch signal is applied, an average value of the potential difference between the electrodes remains unchanged, so as to avoid a perceptible change in display effect.

9. The touch display according to claim 1, wherein

during a time of transmitting the touch signal by the display screen electrode, the potential difference of the touch signal among the different electrode groups maintains constant.

10. The touch display according to claim 1, wherein

among the times of transmitting the touch signal by the display screen electrode, the potential difference of the touch signal among the different electrode groups remains unchanged.

11. The touch display according to claim 1, wherein

the touch signal applied to the row and column electrode groups or the COM electrode is an Alternating Current (AC) signal, or a composite signal of an AC signal and a Direct Current (DC) signal.

12. The touch display according to claim 10, wherein

a waveform of the AC signal component in the touch signal is one of a square wave, a sine wave, a triangular wave, a saw-tooth wave, and other AC waveforms.

13. The touch display according to claim 10, wherein

a frequency of the AC signal component in the touch signal is 10 kHz or above 10 kHz.

14. The touch display according to claim 1, wherein

the active display screen is one of a TFT Liquid Crystal Display (LCD) (TFT-LCD) or other active LCD screens, an active Organic Light Emitting Diode (OLED) display screen, and an active carbon nanotube display screen.