Touch device having switch circuits controlling between touch electrodes and drive chip, touch system and control method thereof

Patent metadata

Field	Value
Publication number	US-11520437-B2
Application number	US-202017258153-A
Country	US
Kind code	B2
Filing date	Mar 31, 2020
Priority date	Mar 31, 2020
Publication date	Dec 6, 2022
Grant date	Dec 6, 2022

Abstract

Embodiments of this disclosure provide a touch device, a touch system and a control method thereof. The touch device includes: a touch screen including: a plurality of touch electrodes, and a plurality of switch circuits corresponding to the plurality of touch electrodes respectively; and a drive chip bound and connected with the touch screen. The touch electrodes are coupled to the drive chip through the corresponding switch circuits. The drive chip is configured to: determine that the touch screen is contacted by an interference object and determine an interference area, according to capacitance values of the touch electrodes during a time period when a stylus is interacting with the touch screen, and disconnect touch electrodes in the interference area from the drive chip through corresponding switch circuits.

First claim

What is claimed is:

1. A control method of a touch system,
wherein the touch system comprises: a touch device and a stylus matching with the touch device;
wherein the touch device comprises:
a touch screen, comprising: a plurality of touch electrodes, and a plurality of switch circuits corresponding to the plurality of touch electrodes respectively; and
a drive chip, bound and connected with the touch screen;

wherein:
the touch electrodes are coupled to the drive chip through the corresponding switch circuits;
the drive chip is configured to:
determine that the touch screen is contacted by an interference object and determine an interference area, according to capacitance values of the touch electrodes during a time period when a stylus is interacting with the touch screen, and
disconnect touch electrodes in the interference area from the drive chip through corresponding switch circuits;

wherein the plurality of switch circuits each comprises: at least two first switch transistors and a second switch transistor;
wherein:
an input terminal of each of the at least two first switch transistors is coupled to the drive chip;
an output terminal of each of the at least two first switch transistors is coupled to a respective one of the touch electrodes;
an input terminal of the second switch transistor is coupled to the drive chip; and
an output terminal of the second switch transistor is coupled to input terminals of the at least two first switch transistors in the same each switch circuit

wherein the control method comprises:
determining, by the drive chip, that the touch screen is contacted by an interference object and determining an interference area, according to capacitance values of the touch electrodes during a time period when the stylus is interacting with the touch screen; and
disconnecting, by the drive chip, touch electrodes in the interference area from the drive chip through corresponding switch circuits;

wherein
said disconnecting, by the drive chip, touch electrodes in the interference area from the drive chip through corresponding switch circuits, comprises:
when all touch electrodes corresponding to a switch circuit are in the interference area, controlling, by the drive chip, the second switch transistor in the switch circuit to be turned off; and/or
when a part of touch electrodes corresponding to a switch circuit are in the interference area, controlling, by the drive chip, the second switch transistor in the switch circuit to be turned on, and controlling first switch transistors corresponding to the touch electrodes in the interference area to be turned off.

2. The control method of claim 1 , wherein the drive chip comprises:
a plurality of processors;
wherein:
the processors are configured to convert analog signals into digital signals; and
the processors are coupled to the plurality of switch circuits.

3. The control method of claim 2 , wherein the processors are coupled to the plurality of switch circuits respectively in one-to-one correspondence.

4. The control method of claim 2 , wherein one of the switch circuits is coupled to at least two of the processors.

5. The control method of claim 1 , wherein
said disconnecting, by the drive chip, touch electrodes in the interference area from the drive chip through corresponding switch circuits, comprises:
controlling, by the drive chip, first switch transistors corresponding to the touch electrodes in the interference area to be turned off.

6. The control method of claim 1 , further comprising:
sending, by the drive chip, a handshake signal to the plurality of touch electrodes;
feeding back, by the stylus, an excitation signal to the plurality of touch electrodes after receiving the handshake signal;
determining, by the drive chip, a contact position of the stylus and the touch screen according to the excitation signal received by the plurality of touch electrodes; and
obtaining a sliding trajectory of the stylus.

7. The control method of claim 6 , wherein said sending, by the drive chip, a handshake signal to the plurality of touch electrodes, comprises:
sending, by the drive chip, the handshake signal to the touch electrodes frame by frame.

8. The control method of claim 7 , wherein said feeding back, by the stylus, an excitation signal to the plurality of touch electrodes after receiving the handshake signal, comprises:
feeding back, by the stylus, the excitation signal to the plurality of touch electrodes in at least two consecutive frames after receiving the handshake signal;
wherein the stylus feeds back the excitation signal once per frame.

Assignees

• Hefei Boe Optoelectronics Tech
• Boe Technology Group Co Ltd
• Beijing Boe Technology Dev Co Ltd

Inventors

• Fang Zhixiang
• Yang Guanglei

Classifications

• G06F3/04162

  for exchanging data with external devices, e.g. smart pens, via the digitiser sensing hardware · CPC title

• G06F3/03545

  Pens or stylus · CPC title

• G06F3/04166

  Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving (Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally G06F3/04184) · CPC title

• G06F3/0418

  for error correction or compensation, e.g. based on parallax, calibration or alignment · CPC title

• G06F3/0446 Primary

  using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes · CPC title