System and method for scanning control of a capacitive touch panel

• US 9,626,044 B2
• Filed: 06/24/2010
• Issued: 04/18/2017
• Est. Priority Date: 06/20/2006
• Status: Active Grant

• Current Assignee: eGalax_eMPIA Technology Inc.
• Original Assignee: eGalax_eMPIA Technology Inc.
• Inventors: Chang, Chin-Fu
• Primary Examiner(s): Sim, Matthew
• Application Number:
  US12/822,828
• Publication Number:
  US 20100259505A1
• Time in Patent Office: 2,490 Days
• Field of Search: 345173, 341 26, 178 1806, 73862041
• CPC Class Codes: G06F 3/0416 Control or interface arrangements specially adapted for digitisers
• 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 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes

Abstract

This invention provides a system for scanning control of a capacitive touch panel. The system includes a driving unit driving a partially neighboring strips of a plurality of first axial conductive strips of the capacitive touch panel, wherein the plurality of first axial conductive strips are parallel to each other, and a first detecting unit detecting one of the partially neighboring strips of first axial conductive strips. By doing so, the influence caused by unintended conducting materials can be kept from the touch point detection for the capacitive touch panel, and the electro-magnetic interference of the capacitive touch panel can be also decreased.

Claims

1. A system for scanning control of a capacitive touch panel,

wherein said capacitive touch panel comprises a plurality of first axial conductive strips and a plurality of second axial conductive strips, said plurality of first axial conductive strips and second axial conductive strips intersect with each other and are electrically isolated;

and

wherein said plurality of first axial conductive strips are parallel to each other and comprises a first group of N first axial conductive strips and a second group of N first axial conductive strips, said N is equal to or greater than three;

said system comprising;

a driving unit, simultaneously driving said first group of said N first axial conductive strips during a first self-capacitive detection and simultaneously driving said second group of said N first axial conductive strips during a second self-capacitive detection; and

a first detecting unit, detecting only one middle first axial conductive strip of said first group during said first self-capacitive detection and detecting only one middle first axial conductive strip of said second group adjacent to said middle first axial conductive strip of said first group during said second self-capacitive detection, wherein only N−

1 first axial conductive strips of said first group and said second group are the same.

2. The system according to claim 1, wherein said second self-capacitive detection is executed after said first self-capacitive detection.

3. The system according to claim 2, wherein said first group and said second group of said first axial conductive strips include 3, 5, or 7 first axial conductive strips.

4. The system according to claim 1, wherein said plurality of first axial conductive strips are X-axial or Y-axial.

5. The system according to claim 1, further comprising a signal processing unit processing a first data receiving from said first detecting unit.

6. The system according to claim 5, further comprising a control unit receiving a second data from said signal processing unit and controlling said driving unit and said first detecting unit.

7. The system according to claim 6, wherein said first data is translated into said second data by including filtering, sampling, amplifying, and analog-to-digital converting.

8. The system according to claim 1,

wherein during a third self-capacitive detection, said driving unit further simultaneously drives a third group of N second axial conductive strips but a second detecting unit detects only one middle second axial conductive strip of said first group;

and

wherein during a fourth self-capacitive detection, said driving unit then simultaneously drives a fourth second group of N second axial conductive strips but said second detecting unit detects only one middle second axial conductive strip of said second group, wherein only N−

1 second axial conductive strips of said third group and said fourth group are the same.

9. The system according to claim 8, wherein said fourth self-capacitive detection is executed after said third self-capacitive detection.

10. The system according to claim 9, wherein said third group and said fourth group of second axial conductive strips include 3, 5, or 7 second axial conductive strips.

11. The system according to claim 8, further comprising a signal processing unit processing a first data receiving from said first and second detecting units through a switching unit.

12. The system according to claim 11, further comprising a control unit receiving a second data from said signal processing unit and controlling said driving unit, said first and second detecting units, and said switching unit.

13. The system according to claim 12, wherein said first data is translated into said second data by including filtering, sampling, amplifying, and analog-to-digital converting.

14. A method for scanning control of a capacitive touch panel,

wherein said capacitive touch panel comprises a plurality of first axial conductive strips and a plurality of second axial conductive strips, said plurality of first axial conductive strips and second axial conductive strips intersect with each other and are electrically isolated;

and

wherein said plurality of first axial conductive strips are parallel to each other and comprises a first group of N first axial conductive strips and a second group of N first axial conductive strips, said N is equal to or greater than three;

said method comprising;

executing a first self-capacitive detection of simultaneously driving said first group of said N first axial conductive strips by a driving unit but only detect a middle first axial conductive strip of said first group by a first detecting unit; and

executing a second self-capacitive detection of simultaneously driving said second group of said N first axial conductive strips by said driving unit but only detect a middle first axial conductive strip of said second group adjacent to said middle first axial conductive strip of said first group by said first detecting unit, wherein only N−

1 first axial conductive strips of said first group and said second group are the same.

15. The method according to claim 14, wherein said second self-capacitive detection is executed after said first self-capacitive detection.

16. The method according to claim 15, wherein said first group and said second group of first axial conductive strips include 3, 5, or 7 first axial conductive strips.

17. The method according to claim 14, wherein said plurality of first axial conductive strips are X-axial or Y-axial.

18. The method according to claim 14, further comprising processing a first data receiving from said first detecting unit by a signal processing unit.

19. The method according to claim 18, further comprising receiving a second data from said signal processing unit and controlling said driving unit and said first detecting unit by a control unit.

20. The method according to claim 19, wherein said first data is translated into said second data by including filtering, sampling, amplifying, and analog-to-digital converting.

21. The method according to claim 14, further comprising:

executing a third self-capacitive detection of simultaneously driving a third group of N second axial conductive strips by said driving unit but only detect a middle second axial conductive strip of said third group by a second detecting unit; and

executing a fourth self-capacitive detection of simultaneously driving a fourth group of N second axial conductive strips by said driving unit but only detect a middle second axial conductive strip of said fourth group adjacent to said middle second axial conductive strip of said third group by said second detecting unit, wherein only N−

1 second axial conductive strips of said third group and said fourth group are the same.

22. The method according to claim 21, wherein said fourth self-capacitive detection is executed after said third self-capacitive detection.

23. The method according to claim 22, wherein said third group and said fourth group of second axial conductive strips include 3, 5, or 7 second axial conductive strips.

24. The method according to claim 21, further comprising processing a first data receiving from said first and second detecting units through a switching unit by a signal processing unit.

25. The method according to claim 24, further comprising receiving a second data from said signal processing unit and controlling said driving unit, said first and second detecting units, and said switching unit by a control unit.

26. The method according to claim 25, wherein said first data is translated into said second data by including filtering, sampling, amplifying, and analog-to-digital converting.