Touch screen apparatus and processing method thereof

• US 9,164,634 B2
• Filed: 02/11/2013
• Issued: 10/20/2015
• Est. Priority Date: 09/20/2012
• Status: Active Grant

• Current Assignee: FocalTech Systems Co.,Ltd
• Original Assignee: FocalTech Systems Co.,Ltd
• Inventors: Mo, Lianghua, Zhang, Jingkai
• Primary Examiner(s): Siddiqui, Md Saiful A
• Application Number:
  US13/764,240
• Publication Number:
  US 20140078099A1
• Time in Patent Office: 981 Days
• Field of Search: 345156-158, 345168-169, 345173-179, 178 1801- 1809, 463 37- 38
• US Class Current: 1/1
• CPC Class Codes: G06F 3/04166 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 Class Codes: G06F 3/04182 Filtering of noise external to the device and not generated by digitiser components
• 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 3/044 by capacitive means

Abstract

A touch screen apparatus and a processing method thereof. In the touch screen apparatus according to the embodiment of the invention, a frequency spectrum analyzing unit determines that a frequency domain signal of a signal received by a receiving unit in the touch screen apparatus or of a signal obtained by processing the signal received by the receiving unit for at least once includes a predetermined noise signal feature, and then a frequency control unit controls the frequency of the signal sent by a sending unit, so that there is as little interference of the noise as possible when the sending unit performs transmission.

Claims

1. A touch screen apparatus comprising a receiving unit, a sending unit, a demodulator, a mutual capacitance connected between the receiving unit and the sending unit, and a data processing and analyzing module, wherein the touch screen apparatus further comprises a frequency spectrum analyzing unit and a frequency control unit;

an output terminal of the receiving unit is connected to an input terminal of the frequency spectrum analyzing unit, and the output terminal of the receiving unit is further connected to the data processing and analyzing module via the demodulator;

the frequency spectrum analyzing unit is configured to determine whether a frequency domain signal of a signal output by the receiving unit or of a signal obtained by processing the signal output by the receiving unit for at least once comprises a predetermined noise signal feature; and

the frequency control unit is connected between the frequency spectrum analyzing unit and a frequency control terminal of the sending unit and is configured to control a frequency of a signal sent by the sending unit when the frequency spectrum analyzing unit determines that a signal received by the receiving unit comprises a noise signal;

wherein the touch screen apparatus further comprises a filter, wherein the filter is connected downstream of the demodulator, the input terminal of the frequency spectrum analyzing unit is connected between the demodulator and the filter, and the output terminal of the receiving unit is connected to the data processing and analyzing module via the demodulator and the filter;

the predetermined noise signal feature comprises a feature that in a frequency band which is centered at a frequency obtained by subtracting a predetermined demodulation value from a signal frequency of the signal sent by the sending unit and has a width equal to a pass-band frequency of the filter, a frequency domain signal peaks at an extra frequency, in addition to the frequency, obtained by subtracting the predetermined demodulation value from the signal frequency of

the signal sent by the sending unit; and

the frequency spectrum analyzing unit is configured to determine whether the frequency domain signal of a signal obtained by demodulating the signal output by the receiving unit peaks in the frequency band at an extra frequency in addition to the frequency obtained by subtracting the predetermined demodulation value from the signal frequency of the signal send by the sensing unit, and to determine that the signal received by the receiving unit comprises the noise signal in a case that the frequency domain signal of the signal obtained by demodulating the signal output by the receiving unit peaks in the frequency band at the extra frequency in addition to the frequency obtained by subtracting the predetermined demodulation value from the signal frequency of the signal sent by the sending unit.

2. The touch screen apparatus according to claim 1, wherein the input terminal of the frequency spectrum analyzing unit is connected downstream of the output terminal of the receiving unit and upstream of the demodulator;

the predetermined noise signal feature comprises a feature that in a frequency band which is centered at a signal frequency of the signal sent by the sending unit and has a width equal to a predetermined pass-band frequency, the frequency domain signal peaks at an extra frequency in addition to the signal frequency; and

the frequency spectrum analyzing unit is configured to determine whether the frequency domain signal peaks in the frequency band at the extra frequency in addition to the signal frequency, and to determine that the signal received by the receiving unit comprises the noise signal in a case that the frequency domain signal peaks in the frequency band at the extra frequency in addition to the signal frequency.

3. The touch screen apparatus according to claim 2, wherein the data processing and analyzing module is configured to determine the frequency of the noise signal according to at least two signals obtained after demodulation and filtering of signals received by the receiving unit and acquired at different time instants.

4. The touch screen apparatus according to claim 1, wherein the input terminal of the frequency spectrum analyzing unit is connected between a filter and the data processing and analyzing module, the predetermined noise signal feature comprises a feature that the frequency domain signal peaks at an extra frequency in addition to a zero frequency point;

and

the frequency spectrum analyzing unit is configured to determine whether the frequency domain signal of a signal obtained by demodulating and filtering the signal output by the receiving unit peaks at the extra frequency in addition to the zero frequency point, and to determine that the signal received by the receiving unit comprises the noise signal in a case that the frequency domain signal of the signal obtained by demodulating and filtering the signal output by the receiving unit peaks at the extra frequency in addition to the zero frequency point.

5. The touch screen apparatus according to claim 4, wherein the data processing and analyzing module is configured to determine the frequency of the noise signal according to at least two signals obtained after demodulation and filtering of signals received by the receiving unit and acquired at different time instants.

6. The touch screen apparatus according to claim 1, wherein the data processing and analyzing module is configured to determine the frequency of the noise signal according to at least two signals obtained after demodulation and filtering of signals received by the receiving unit and acquired at different time instants.

7. A processing method for a touch screen apparatus, comprising:

acquiring a frequency domain signal of a signal received by a receiving unit in the touch screen apparatus or of a signal obtained by processing the signal received by the receiving unit for at least once when the touch screen apparatus detects a mutual capacitance; and

determining that the acquired frequency domain signal comprises a predetermined noise signal feature, and controlling a frequency of a signal sent by a sending unit in the touch screen apparatus so that the sending unit sends the signal according to the controlled frequency,

wherein;

in response to acquiring the frequency domain signal of the signal received by the receiving unit, the predetermined noise signal feature comprises a feature that in a frequency band which is centered at a signal frequency of the signal sent by the sending unit in the touch screen apparatus and has a width equal to a predetermined pass-band frequency, the frequency domain signal peaks at an extra frequency in addition to the signal frequency;

in response to acquiring the frequency domain signal of a signal obtained by demodulating the signal received by the receiving unit, the predetermined noise signal feature comprises a feature that in a frequency band which is centered at a frequency obtained by subtracting a predetermined demodulation value from the signal frequency of the signal sent by the sending unit in the touch screen apparatus and has a width equal to a pass-band frequency of a filter, the frequency domain signal peaks at an extra frequency in addition to the frequency obtained by subtracting the predetermined demodulation value from the signal frequency of the signal sent by the sending unit; and

in response to acquiring the frequency domain signal of a signal obtained by demodulating and filtering the signal received by the receiving unit, the predetermined noise signal feature comprises a feature that the frequency domain signal peaks at an extra frequency in addition to a zero frequency point.

8. The method according to claim 7, further comprising determining a frequency of the noise signal according to at least two signals obtained after demodulation and filtering of signals received by the receiving unit and acquired at least two different time instants.

9. A touch screen apparatus comprising a receiving unit, a sending unit, a demodulator, a mutual capacitance, a data processing and analyzing module, a frequency spectrum analyzing unit and a frequency control unit;

wherein;

when the touch screen apparatus detects the mutual capacitance, the receiving unit receives a noise from the mutual capacitance and a signal sent by the sending unit via the mutual capacitance, and the receiving unit sends the noise and the signal sent by the sending unit to the data processing and analyzing module via the demodulator and to the frequency spectrum analyzing unit;

the frequency spectrum analyzing unit acquires a frequency domain signal of a signal received by the receiving unit in the touch screen apparatus or of a signal obtained by processing the signal received by the receiving unit for at least once; and

determines that the acquired frequency domain signal comprises a predetermined noise signal feature, and controls a frequency of a signal sent by the sending unit in the touch screen apparatus to make the sending unit send the signal to the sending unit according to the controlled frequency,

wherein the touch screen apparatus further comprising a filter, wherein the receiving unit sends the noise and the signal sent by the sending unit to the frequency spectrum analyzing unit and to the filter via the demodulator;

the predetermined noise signal feature comprises a feature that in a frequency band which is centered at a frequency obtained by subtracting a predetermined demodulation value from a signal frequency of the signal sent by the sending unit and has a width equal to a pass-band frequency of the filter, the frequency domain signal peaks at an extra frequency in addition to the frequency obtained by subtracting the predetermined demodulation value from the signal frequency of the signal sent by the sending unit; and

the frequency spectrum analyzing unit is configured to determine whether the frequency domain signal of a signal obtained by demodulating the signal output by the receiving unit peaks in the frequency band at the extra frequency in addition to the frequency obtained by subtracting the predetermined demodulation value from the signal frequency of the signal sent by the sending unit, and to determine that the signal received by the receiving unit comprises the noise signal in a case that the frequency domain signal of the signal obtained by demodulating the signal output by the receiving unit peaks in the frequency band at the extra frequency in addition to the frequency obtained by subtracting the predetermined demodulation value from the signal frequency of the signal sent by the sending unit.

10. The touch screen apparatus according to claim 9, wherein the predetermined noise signal feature comprises a feature that in a frequency band which is centered at a signal frequency of the signal sent by the sending unit and has a width equal to a predetermined pass-band frequency, the frequency domain signal peaks at an extra frequency in addition to the signal frequency;

and

the frequency spectrum analyzing unit is configured to determine whether the frequency domain signal peaks in the frequency band at the extra frequency in addition to the signal frequency, and to determine that the signal received by the receiving unit comprises the noise signal in a case that the frequency domain signal peaks in the frequency band at the extra frequency in addition to the signal frequency.

11. The touch screen apparatus according to claim 10, wherein the data processing and analyzing module is configured to determine the frequency of the noise signal according to at least two signals obtained after demodulation and filtering of signals received by the receiving unit and acquired at different time instants.

12. The touch screen apparatus according to claim 9, wherein the receiving unit sends the noise and the signal sent by the sending unit to the frequency spectrum analyzing unit and to data processing and analyzing module via the demodulator and a filter, the predetermined noise signal feature comprises a feature that the frequency domain signal peaks at an extra frequency in addition to a zero frequency point;

and

the frequency spectrum analyzing unit is configured to determine whether the frequency domain signal of a signal obtained by demodulating and filtering the signal output by the receiving unit peaks at the extra frequency in addition to the zero frequency point, and to determine that the signal received by the receiving unit comprises the noise signal in a case that the frequency domain signal of the signal obtained by demodulating and filtering the signal output by the receiving unit peaks at the extra frequency in addition to the zero frequency point.

13. The touch screen apparatus according to claim 12, wherein the data processing and analyzing module is configured to determine the frequency of the noise signal according to at least two signals obtained after demodulation and filtering of signals received by the receiving unit and acquired at different time instants.

14. The touch screen apparatus according to claim 9, wherein the data processing and analyzing module is configured to determine the frequency of the noise signal according to at least two signals obtained after demodulation and filtering of signals received by the receiving unit and acquired at different time instants.