Method of identifying touch event on touch panel by shape of signal group and computer readable medium thereof

• US 9,075,465 B2
• Filed: 02/19/2013
• Issued: 07/07/2015
• Est. Priority Date: 02/19/2013
• Status: Active Grant

• Current Assignee: Himax Technologies Ltd. (Himax Technologies Incorporated)
• Original Assignee: Himax Technologies Ltd. (Himax Technologies Incorporated)
• Inventors: Tai, Shen-Feng, Liu, Chun-Yen, Lee, Chin-Lin, Liu, Jui-Min
• Primary Examiner(s): SHAH, PRIYANK J
• Application Number:
  US13/769,840
• Publication Number:
  US 20140232661A1
• Time in Patent Office: 868 Days
• Field of Search: 345/156, 345/173, 345/174, 382312-314, 178/18.01, 178/18.03, 178/18.06
• US Class Current: 1/1
• CPC Class Codes: G06F 2203/04104 Multi-touch detection in digitiser, i.e. details about the simultaneous detection of a plurality of touching locations, e.g. multiple fingers or pen and finger
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/041661 using detection at multiple resolutions, e.g. coarse and fine scanning; using detection within a limited area, e.g. object tracking window

Abstract

An exemplary method of identifying a touch event on a touch panel is provided. The touch panel includes a plurality of sensing blocks. The sensing blocks have a plurality of corresponding sensing values generated in response to the touch event. The exemplary method includes the following steps: selecting a processing region on the touch panel, wherein the processing region comprises at least a portion of sensing blocks each having a sensing value greater than a threshold; deriving a first value and a second value from sensing values of sensing blocks included in the processing region; calculating a ratio of the first value to the second value; and identifying the touch event according to at least the ratio.

Claims

1. A method of identifying a touch event on a touch panel, the touch panel comprising a plurality of sensing blocks, the sensing blocks having a plurality of corresponding sensing values generated in response to the touch event, the method comprising:

selecting a processing region on the touch panel, wherein the processing region comprises at least a portion of sensing blocks each having a sensing value greater than a threshold;

deriving a first value and a second value from sensing values of sensing blocks included in the processing region, wherein at least one of sensing values used for deriving the first value is greater than the threshold, and at least one of sensing values used for deriving the second value is greater than the threshold;

calculating a ratio of the first value to the second value; and

identifying the touch event according to at least the ratio;

wherein the step of identifying the touch event according to at least the ratio comprises;

comparing the ratio with a predetermined value to identify the touch event, wherein when the ratio is greater than the predetermined value, it is determined that the touch event is a multi-touch event.

2. The method of claim 1, wherein the step of deriving the first value and the second value comprises:

generating the first value by averaging sensing values of at least a portion of the sensing blocks included in the processing region.

3. The method of claim 2, wherein at least a maximum sensing value of the sensing values of the sensing blocks included in the processing region is not involved in generating the first value.

4. The method of claim 2, wherein the step of deriving the first value and the second value comprises:

selecting a maximum sensing value of the sensing values of the sensing blocks included in the processing region as the second value.

5. The signal processing method of claim 1, wherein the processing region is a quadrangle.

6. The signal processing method of claim 5, wherein the processing region covers all the sensing blocks each having the sensing value greater than the threshold.

7. The signal processing method of claim 6, wherein the processing region is a minimum quadrangle which covers all the sensing blocks each having the sensing value greater than the threshold.

8. The signal processing method of claim 5, wherein the processing region has a first sensing block and a second sensing block located at corners, the first sensing block has a maximum sensing value of the sensing values of the sensing blocks included in the processing region, and the second sensing block has a sub-maximum sensing value of the sensing values of the sensing blocks included in the processing region.

9. The signal processing method of claim 8, wherein the first sensing block and the second sensing block are arranged diagonally in the processing region.

10. The signal processing method of claim 1, further comprising:

performing a self-sensing operation upon the touch panel to obtain a self-sensing result;

and the step of identifying the touch event according to at least the ratio comprises;

identifying the touch event according to the ratio and the self-sensing result.

11. The method of claim 10, wherein the step of identifying the touch event according to the ratio and the self-sensing result comprises:

when at least one of the ratio and the self-sensing result indicates that there is more than one touch point on the touch panel, determining that the touch event is a multi-touch event.

12. The method of claim 1, wherein when the ratio is less than the predetermined value, it is determined that the touch event is a single-touch event.

13. A non-transitory computer readable medium having a program code stored therein, wherein when executed by a processor, the program code causes the processor to execute the following steps:

selecting a processing region on the touch panel, wherein the processing region comprises at least a portion of sensing blocks each having a sensing value greater than a threshold;

deriving a first value and a second value from sensing values of sensing blocks included in the processing region, wherein at least one of sensing values used for deriving the first value is greater than the threshold, and at least one of sensing values used for deriving the second value is greater than the threshold;

calculating a ratio of the first value to the second value; and

identifying the touch event according to at least the ratio;

wherein the step of identifying the touch event according to at least the ratio comprises;

comparing the ratio with a predetermined value to identify the touch event, wherein when the ratio is greater than the predetermined value, it is determined that the touch event is a multi-touch event.

14. The non-transitory computer readable medium of claim 13, wherein deriving the first value and the second value comprises:

generating the first value by averaging sensing values of at least a portion of the sensing blocks included in the processing region.

15. The non-transitory computer readable medium of claim 14, wherein at least a maximum sensing value of the sensing values of the sensing blocks included in the processing region is not involved in generating the first value.

16. The non-transitory computer readable medium of claim 14, wherein deriving the first value and the second value comprises:

selecting a maximum sensing value of the sensing values of the sensing blocks included in the processing region as the second value.

17. The non-transitory computer readable medium of claim 13, wherein the processing region is a quadrangle.

18. The non-transitory computer readable medium of claim 17, wherein the processing region covers all the sensing blocks each having the sensing value greater than the threshold.

19. The non-transitory computer readable medium of claim 18, wherein the processing region is a minimum quadrangle which covers all the sensing blocks each having the sensing value greater than the threshold.

20. The non-transitory computer readable medium of claim 17, wherein the processing region has a first sensing block and a second sensing block located at corners, the first sensing block has a maximum sensing value of the sensing values of the sensing blocks included in the processing region, and the second sensing block has a sub-maximum sensing value of the sensing values of the sensing blocks included in the processing region.

21. The non-transitory computer readable medium of claim 18, wherein the first sensing block and the second sensing block are arranged diagonally in the processing region.

22. The non-transitory computer readable medium of claim 13, wherein the program code further causes the processor to perform a self-sensing operation upon the touch panel to obtain a self-sensing result, and the step of identifying the touch event according to at least the ratio comprises:

identifying the touch event according to the ratio and the self-sensing result.

23. The non-transitory computer readable medium of claim 22, wherein identifying the touch event according to the ratio and the self-sensing result comprises:

when at least one of the ratio and the self-sensing result indicates that there is more than one touch point on the touch panel, determining that the touch event is a multi-touch event.

24. The non-transitory computer readable medium of claim 13, wherein when the ratio is less than the predetermined value, it is determined that the touch event is a single-touch event.