Touch screen and touch point positioning method

Patent metadata

Field	Value
Publication number	US-9817522-B2
Application number	US-201514646088-A
Country	US
Kind code	B2
Filing date	Jan 5, 2015
Priority date	Sep 24, 2014
Publication date	Nov 14, 2017
Grant date	Nov 14, 2017

Abstract

A touch screen and a touch point positioning method are disclosed. The touch screen comprises a display panel and a touch point positioning device, the touch point positioning device comprises a timing unit, a calculating unit and n receiving units, the receiving units are provided in edge areas of the display panel, the receiving units are connected with the timing unit, and the timing unit is connected with the calculating unit. According to technical solutions of the present invention, the receiving units receive an acoustic wave signal generated at a touch point when the display panel is touched, the timing unit records reception times when the receiving units receive the acoustic wave signal, and the calculating unit calculates a position coordinate of the touch point on the display panel according to the reception times of the receiving units recorded by the timing unit, thus achieving positioning of the touch point.

First claim

The invention claimed is:

1. A touch screen, comprising a display panel and a touch point positioning device, the touch point positioning device comprising a timing unit, a calculating unit and n receiving units, where n≧3, wherein
the receiving units are provided in edge areas of the display panel, and the receiving units are used for receiving an acoustic wave signal generated at a touch point when the display panel is touched;
the timing unit is used for recording reception times when the receiving units receive the acoustic wave signal; and

the calculating unit is used for calculating a position coordinate of the touch point on the display panel according to the reception times of the receiving units recorded by the timing unit; wherein
the positioning device further comprises a storage unit, the storage unit is used for pre-storing position coordinates of a plurality of reference positions on the display panel and corresponding reception times of the receiving units when the reference positions are touched,
the calculating unit comprises a time coordinate generating module and a calculating module,
the time coordinate generating module is used for generating a corresponding reception time coordinate of the touch point in an n-dimensional coordinate system according to the reception times of the receiving units recorded by the timing unit and according to a preset arrangement sequence of the receiving units, and generating corresponding reception time coordinates of the reference positions in the n-dimensional coordinate system according to the corresponding reception times of the receiving units when the reference positions are touched stored in the storage unit and according to the preset arrangement sequence of the receiving units; and
the calculating module is used for respectively calculating Euclidean distances between the reference positions and the touch point according to the reception time coordinate of the touch point and the reception time coordinates of the reference positions in the n-dimensional coordinate system, and determining a reference position at a minimum Euclidean distance from the touch point, so as to determine the position coordinate of the touch point on the display panel as the position coordinate corresponding to the reference position at the minimum Euclidean distance from the touch point.

2. The touch screen of claim 1 , wherein the timing unit is started when any receiving unit in all the receiving units receives the acoustic wave signal, is stopped when all the receiving units receive the acoustic wave signal, and records the corresponding reception time of the receiving unit receiving the acoustic wave signal first as an initial time.

3. The touch screen of claim 2 , wherein
the touch point positioning device further comprises a counting unit, the counting unit is used for counting the number of the receiving unit(s) receiving the acoustic wave signal; when the count value in the counting unit is 1, the counting unit generates and sends a timing start signal to the timing unit, and when the count value in the counting unit is n, the counting unit generates and sends a timing termination signal to the timing unit, and the counting unit resets the count value,
the timing unit is started when receiving the timing start signal and is stopped when receiving the timing termination signal.

4. The touch screen of claim 1 , wherein
the receiving units are piezoelectric sensors, the piezoelectric sensors are used for generating corresponding electrical signals when receiving the acoustic wave signal, and sending the electrical signals to the timing unit, and
the timing unit sequentially receives the electrical signals generated by the piezoelectric sensors and records the corresponding reception times of the receiving units receiving the acoustic wave signal according to the received electrical signals.

5. The touch screen of claim 1 , wherein the touch point positioning device comprises three receiving units, and the three receiving units are not located on a same straight line.

6. The touch screen of claim 1 , wherein the touch point positioning device comprises four receiving units, the display panel has a rectangular shape, and the four receiving units are respectively located at midpoints of four sides of the display panel.

7. A touch point positioning method of a touch screen, the touch screen comprising a display panel and a touch point positioning device, the touch point positioning device comprising a timing unit, a calculating unit and n receiving units, where n 3 , the receiving units being provided in edge areas of the display panel, the touch point positioning method comprising steps of:
receiving, by the receiving units, an acoustic wave signal generated at a touch point when the display panel is touched;
recording, by the timing unit, reception times when the receiving units receive the acoustic wave signal; and

calculating, by the calculating unit, a position coordinate of the touch point on the display panel according to the reception times of the receiving units recorded by the timing unit; wherein
the touch point positioning device further comprises a storage unit, and prior to the step of receiving, by the receiving units, an acoustic wave signal generated at a touch point when the display panel is touched, the touch point positioning method further comprises:
pre-storing by the storage unit, position coordinates of a plurality of reference positions on the display panel and corresponding reception times of the receiving units when the reference positions are touched,
the calculating unit comprises a time coordinate generating module and a calculating module, and the step of calculating, by the calculating unit, the position coordinate of the touch point on the display panel according to the reception times of the receiving units recorded by the timing unit comprises:
generating, by the time coordinate generating module, a corresponding reception time coordinate of the touch point in an n-dimensional coordinate system according to the reception times of the receiving units recorded by the timing unit and according to a preset arrangement sequence of the receiving units, and generating corresponding reception time coordinates of the reference positions in the n-dimensional coordinate system according to the corresponding reception times of the receiving units when the reference positions are touched stored in the storage unit and according to the preset arrangement sequence of the receiving units; and
respectively calculating Euclidean distances between the reference positions and the touch point according to the reception time coordinate of the touch point and the reception time coordinates of the reference positions in the n-dimensional coordinate system, and determining a reference position at a minimum Euclidean distance from the touch point, by the calculating module, so as to determine the position coordinate of the touch point on the display panel as the position coordinate corresponding to the reference position at the minimum Euclidean distance from the touch point.

8. The touch point positioning method of the touch screen of claim 7 , wherein the timing unit is started when any receiving unit in all the receiving units receives the acoustic wave signal, is stopped when all the receiving units receive the acoustic wave signal, and records the corresponding reception time of the receiving unit receiving the acoustic wave signal first as an initial time.

Assignees

• Boe Technology Group Co Ltd
• Hefei Xinsheng Optoelectronics Technology Co Ltd
• Hefei Xinsheng Optoelectronics Technology Co Ltd

Inventors

• Sha Jin

Classifications

• G06F3/043 Primary

  using propagating acoustic waves · CPC title

• G06F3/0436

  in which generating transducers and detecting transducers are attached to a single acoustic waves transmission substrate · CPC title

• G06F3/0416

  Control or interface arrangements specially adapted for digitisers · CPC title

• G06F1/3262

  Power saving in digitizer or tablet · CPC title

• G06F3/0412

  Digitisers structurally integrated in a display · CPC title