Apparatus and method for detecting a touch

• US 10,067,611 B2
• Filed: 11/17/2011
• Issued: 09/04/2018
• Est. Priority Date: 10/05/2011
• Status: Active Grant

• Current Assignee: Melfas Incorporated
• Original Assignee: Melfas Incorporated
• Inventors: Nam, Sung-Sik
• Primary Examiner(s): Chang, Kent
• Assistant Examiner(s): Edwards, Mark
• Application Number:
  US14/349,759
• Publication Number:
  US 20140240291A1
• Time in Patent Office: 2,483 Days
• Field of Search: 345174-179
• CPC Class Codes: G06F 2203/04111 Cross over in capacitive digitiser, i.e. details of structures for connecting electrodes of the sensing pattern where the connections cross each other, e.g. bridge structures comprising an insulating layer, or vias through substrate
• CPC Class Codes: G06F 3/04164 Connections between sensors and controllers, e.g. routing lines between electrodes and connection pads
• 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 3/044 by capacitive means
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes

Abstract

There is disclosed an apparatus for detecting touch including a touch element comprising a plurality of touch detecting electrodes arranged therein, a touch element controller for acquiring detection signals from the touch detection electrodes and determining presence of touch in the touch element, wherein the touch element controller includes a receiving unit for receiving the detection signals from the touch detection electrodes and grouping the detection signals into one or more detection signal groups, a memory for storing a detection signal value limit, a signal extracting unit for extracting the maximum detection value out of the detection signal values of the detection for each of the detection signals, a calculating unit for calculating an adjustment variable by deducting the detection signal value limit from the maximum detection signal value for each of the detection groups, and a touch determination unit for determining presence of touch in the touch element, using the adjustment variable.

Claims

1. An apparatus for detecting touch comprising:

a touch element comprising a plurality of touch detecting electrodes arranged therein; and

a touch element controller for acquiring detection signals from the touch detection electrodes and determining presence of touch in the touch element,

wherein the touch element controller comprises,

a receiving unit for receiving the detection signals from the touch detection electrodes and grouping the detection signals into one or more detection signal groups;

a memory for storing a detection signal value limit that represents a maximum value of a detection signal that is indicative that the touch element is touched;

a signal extracting unit for determining for each of the one or more detection signal groups a maximum detection signal value from amongst the detection signals included in the detection signal group;

a calculating unit for calculating an adjustment variable for each of the detection signal groups by deducting the detection signal value limit from the maximum detection signal value in the detection signal group; and

a touch determination unit for;

adjusting each of the detection signals in each of the one or more detection signal groups by deducting a product of the adjustment variable for the detection signal group and an adjustment factor for the detection signal from the detection signal, a magnitude of the adjustment factor for each detection signal based on a magnitude of noise caused by a rear surface touch of a touch detection electrode that generated the detection signal; and

determining presence of touch in the touch element based on whether the adjusted detection signals included in each of the detection signal groups is greater than a detection signal critical value that describes a minimum value of a detection signal that is indicative that the touch element is touched.

2. The apparatus for detecting the touch of claim 1, wherein the adjustment factor has the maximum value in a detection signal having the maximum detection signal value, and

the size of the adjustment factor is reduced based on a distance with a touch detection electrode in which the detection signal having the maximum detection signal value is detected.

3. The apparatus for detecting the touch of claim 1, wherein the touch determination unit generates the detection signal critical value by adding the adjustment variable to the detection signal critical value for each of the detection signal groups.

4. The apparatus for detecting the touch of claim 1, wherein the touch determination unit:

determines a number of touches of the touch element, using the detection signals,

calculates a normal detection rate based on the number of touches,

generates the adjusted detection signals based on the adjustment variable,

calculates a rate of adjusted detection signals that are larger than the detection signal critical values out of the adjusted detection signals, and

determines whether to perform re-adjustment by comparing the calculated rate with a normal detection rate.

5. The apparatus for detecting the touch of claim 1, wherein the calculating unit calculates the adjustment variable responsive to determining that the extracted maximum detection value is greater than the detection signal value limit.

6. An apparatus for detecting touch comprising:

a display panel for displaying an image;

a display panel controller for driving the display panel;

a touch element arranged on one surface of the display panel, the touch element comprising a plurality of touch detecting electrodes arranged therein; and

a touch element controller for acquiring detection signals from the touch detection electrodes and determining presence of touch in the touch element,

wherein the touch element controller comprises,

a receiving unit for receiving the detection signals from the touch detection electrodes and grouping the detection signals into one or more detection signal groups;

a memory for storing a detection signal value limit that represents a maximum value of a detection signal that is indicative that the touch element is touched;

a signal extracting unit for determining for each of the one or more detection signal groups a maximum detection signal value from amongst the detection signals included in the detection signal group;

a calculating unit for calculating an adjustment variable for each of the detection groups by deducting the detection signal value limit from the maximum detection signal value in the detection signal group; and

a touch determination unit for;

adjusting each of the detection signals in each of the one or more detection signal groups by deducting a product of the adjustment variable for the detection signal group and an adjustment factor for the detection signal from the detection signal, a magnitude of the adjustment factor for each detection signal based on a magnitude of noise caused by a rear surface touch of a touch detection electrode that generated the detection signal; and

determining presence of touch in the touch element, based on whether the adjusted detection signals included in each of the detection signal groups is greater than a detection signal critical value that describes a minimum value of a detection signal that is indicative that the touch element is touched.

7. An apparatus for detecting touch comprising:

a touch element comprising a plurality of touch detection electrodes comprising a plurality of first touch detection electrodes and a plurality of second touch detection electrodes; and

a touch element controller for applying a driving signal a predetermined number of the second touch detection electrodes and determining presence of touch in the touch element by acquiring detection signals generated between the first touch detection electrodes and the second touch detection electrodes,

wherein the touch element controller comprises,

a receiving unit for receiving the detection signals from the first touch detection electrodes;

a memory for storing a detection signal value limit that represents a maximum value of a detection signal that is indicative that the touch element is touched;

a signal extracting unit for determining for each of the one or more detection signal groups a maximum detection signal value from amongst the detection signals included in the detection signal group;

a calculating unit for calculating an adjustment variable for each of the detection signal groups by deducting the detection signal value from the maximum detection signal value in the detection signal group; and

a touch determination unit for;

adjusting each of the detection signals in each of the one or more detection signal groups by deducting a product of the adjustment variable for the detection signal group and an adjustment factor for the detection signal from the detection signal, a magnitude of the adjustment factor for each detection signal based on a magnitude of noise caused by a rear surface touch of a touch detection electrode that generated the detection signal; and

determining presence of touch in the touch element, based on whether the adjusted detection signals included in each of the detection signal groups is greater than a detection signal critical value that describes a minimum value of a detection signal that is indicative that the touch element is touched.

8. The apparatus for detecting the touch of claim 7, wherein the adjustment factor has the maximum value in a detection signal having the maximum detection signal value, and

the size of the adjustment factor is reduced based on a distance with a touch detection electrode in which the detection signal having the maximum detection signal value is detected.

9. The apparatus for detecting the touch of claim 7, wherein the touch determination unit generates the detection signal critical value by adding the adjustment variable to the detection signal critical value for each of the detection signal groups.

10. The apparatus for detecting the touch of claim 7, wherein the touch determination unit:

determines a number of touches of the touch element, using the detection signals,

calculates a normal detection rate based on the number of touches,

generates the adjusted detection signals based on the adjustment variable,

calculates a rate of adjusted detection signals that are larger than the detection signal critical values out of the adjusted detection signals, and

determines whether to perform re-adjustment by comparing the calculated rate with a normal detection rate.

11. The apparatus for detecting the touch of claim 7, wherein the calculating unit calculates the adjustment variable responsive to determining that the extracted maximum detection value is greater than the detection signal value limit.

12. A method for detecting touch comprising:

generating detection signals and acquiring the detection signals that are grouped into one or more detection signal groups;

determining for each of the one or more detection signal groups a maximum detection signal value from amongst the detection signals included in the detection signal group;

calculating an adjustment variable for each of the detection signal groups by deducting a detection signal value limit from the maximum detection signal value in the detection signal group;

adjusting each of the detection signals in each of the one or more detection signal groups by deducting a product of the adjustment variable for the detection signal group and an adjustment factor for the detection signal from the detection signal, a magnitude of the adjustment factor for each detection signal based on a magnitude of noise caused by a rear surface touch of a touch detection electrode that generated the detection signal; and

determining presence of touch in a touch element based on whether the adjusted detection signals included in each of the detection signal groups is greater than a detection signal critical value that describes a minimum value of a detection signal that is indicative that the touch element is touched.

13. The method for detecting the touch of claim 12, wherein the adjustment factor has the maximum value in a detection signal having the maximum detection signal value, and

the size of the adjustment factor is reduced based on a distance with a touch detection electrode in which the detection signal having the maximum detection signal value is detected.

14. The method for detecting the touch of claim 12, wherein the acquiring of the detection signals comprises acquiring the detection signals from touch detection electrodes of the touch element, and

the determining of the presence of the touch comprises,

grouping the touch detection electrodes in accordance with a region of the touch element;

generating the adjusted detection signal by deducting a product of the adjustment variable and an adjustment factor from the detection signals for each of the grouped touch detection electrodes; and

determining presence of touch in the touch element, using the adjusted detection signals, and the adjustment factor is defined different for each of the touch detection electrode group.

15. The method for detecting the touch of claim 12, wherein the determining of the presence of the touch comprises,

generating the detection signal critical value by adding the adjustment variable to a detection signal critical value for each of the detection signal groups.

16. The method for detecting the touch of claim 12, further comprising:

determining whether to re-adjust noise,

wherein the determining whether to re-adjust the noise comprises,

determining a number of touches in the touch element, using the detection signals;

extracting a normal detection rate based on the number of the touches;

generating an adjusted detection signal, using the adjustment variable;

calculating a rate of adjusted detection signals that are larger than the detection signal critical value; and

determining whether to re-adjust noise by comparing the calculated rate with the normal detection rate.

17. The method for detecting the touch of claim 12, wherein the adjustment variable is calculated responsive to determining that the extracted maximum detection value is greater than the detection signal value limit.

18. A method for detecting touch comprising:

generating detection signals and acquiring the detection signals that are grouped into one or more detection signal groups;

determining for each of the one or more detection signal groups a maximum detection signal value from amongst the detection signals included in the detection signal group;

calculating an adjustment variable based on a ratio of a detection signal value limit and the maximum detection signal value, the maximum detection signal value representing a maximum value of a detection signal that is indicative that the touch element is touched;

adjusting each of the detection signals in each of the one or more detection signal groups by deducting a product of the adjustment variable and an adjustment factor for the detection signal from the detection signal, a magnitude of the adjustment factor for each detection signal based on a magnitude of noise caused by a rear surface touch of a touch detection electrode that generated the detection signal; and

determining presence of touch in a touch element based on the adjusted detection signals and a detection signal critical value that describes a minimum value of a detection signal that is indicative that the touch element is touched.