High Noise Immunity and High Spatial Resolution Mutual Capacitive Touch Panel

• US 20120299868A1
• Filed: 12/20/2011
• Published: 11/29/2012
• Est. Priority Date: 05/25/2011
• Status: Abandoned Application

• Current Assignee: Avago Technologies General IP PTE Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Sobel, David, Walley, John, Ranganathan, Sumant, Bhagavat, Milind
• Application Number:
  US13/331,337
• Publication Number:
  US 20120299868A1
• Time in Patent Office: Days
• US Class Current: 345/174
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• 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

A mutual capacitive touch panel providing improved noise immunity and improved spatial resolution is described. The touch panel includes a drive line having a plurality of drive electrodes. The touch panel further includes a sense line arranged at an angle with respect to the drive line and the sense line having a plurality of sense electrodes, such that each of the plurality of sense electrodes overlies one of the plurality of drive electrodes. The touch panel is further configured such that a perimeter of each of the plurality of drive electrodes encompasses a perimeter of at least one of the plurality of sense electrodes.

Claims

1. A touch panel comprising:

a drive line having a plurality of drive electrodes; and

a sense line arranged at an angle with respect to the drive line and the sense line having a plurality of sense electrodes, wherein each of the plurality of sense electrodes overlies one of the plurality of drive electrodes;

wherein a perimeter of each of the plurality of drive electrodes encompasses a perimeter of at least one of the plurality of sense electrodes.

2. The touch panel of claim 1, wherein a shape of the plurality of sense electrodes is selected from the group consisting of a circle, a square, a rectangle and a diamond.

3. The touch panel of claim 1, wherein a shape of the plurality of drive electrodes is selected from the group consisting of a circle, a square, a rectangle and a diamond.

4. The touch panel of claim 1 further comprising a transparent dielectric disposed between the drive line and the sense line.

5. The touch panel of claim 1, wherein each of the plurality of sense electrodes comprises one or more conductive loops.

6. The touch panel of claim 5, wherein each of the plurality of sense electrodes further comprises one or more conductive fingers extending away from the one or more conductive loops.

7. The touch panel of claim 1, wherein the perimeter of each of the plurality of drive electrodes encompassing the perimeter of one of the plurality of sense electrodes enables a plurality of fringe field lines to extend above and away from each of the plurality of sense electrodes.

8. The touch panel of claim 1 further comprising:

a plurality of drive electrode groups, each comprising a plurality of drive lines electrically connected together, the drive line included in one of the plurality of drive electrode groups; and

a plurality of sense electrode groups, each comprising a plurality of sense lines electrically connected together, the sense line included in one of the plurality of sense electrode groups.

9. The touch panel of claim 8, wherein the plurality of drive electrode groups are interdigitated such that each of the plurality of drive lines from each of the plurality of drive electrode groups is disposed adjacent to one of the plurality of drive lines from another one of the plurality of drive electrode groups.

10. The touch panel of claim 8, wherein the plurality of sense electrode groups are interdigitated such that each of the plurality of sense lines from each of the plurality of sense electrode groups is disposed adjacent to one of the plurality of sense lines from another one of the plurality of sense electrode groups.

11. A touch panel comprising:

a plurality of drive electrode groups, each comprising a plurality of drive lines electrically connected together; and

a plurality of sense electrode groups, each comprising a plurality of sense lines electrically connected together and arranged at an angle with respect to the plurality of drive lines;

wherein the plurality of drive electrode groups are interdigitated such that each of the plurality of drive lines from each of the plurality of drive electrode groups is disposed adjacent to one of the plurality of drive lines from another one of the plurality of drive electrode groups.

12. The touch panel of claim 11, wherein the plurality of sense electrode groups are interdigitated such that each of the plurality of sense lines from each of the plurality of sense electrode groups is disposed adjacent to one of the plurality of sense lines from another one of the plurality of sense electrode groups.

13. The touch panel of claim 11, wherein each one of the plurality of drive lines comprises a plurality of drive electrodes and each of the plurality of sense lines comprises a plurality of sense electrodes arranged such that each of the plurality of sense electrodes overlies one of the plurality of drive electrodes.

14. A method comprising:

providing a plurality of conductive drive lines, each including a plurality of drive electrodes; and

providing a plurality of conductive sense lines at an angle with respect to the plurality of conductive drive lines, each of the plurality of conductive sense lines including a plurality of sense electrodes such that each of the plurality of sense electrodes overlies one of the plurality of drive electrodes;

wherein a perimeter of each of the plurality of drive electrodes encompasses a perimeter of one of the plurality of sense electrodes to shield the plurality of sense electrodes from electromagnetic noise.

15. The method of claim 14, wherein a shape of the plurality of sense electrodes and a shape of the plurality of drive electrodes are selected from the group consisting of a circle, a square, a rectangle and a diamond.

16. The method of claim 14, wherein each of the plurality of sense electrodes are formed to comprise one or more conductive loops such that a plurality of fringe field lines extend above and away from each of the plurality of sense electrodes.

17. The method of claim 16, wherein each of the plurality of sense electrodes are formed to further comprise one or more conductive fingers extending away from the one or more conductive loops.

18. The method of claim 14, further comprising:

electrically connecting the plurality of drive lines together to form a plurality of drive electrode groups; and

electrically connecting the plurality of sense lines together to form a plurality of sense electrode groups.

19. The method of claim 18, wherein the plurality of sense electrode groups are interdigitated such that each of the plurality of sense lines from each of the plurality of sense electrode groups is disposed adjacent to one of the plurality of sense lines from another one of the plurality of sense electrode groups.

20. The method of claim 18, wherein the plurality of drive electrode groups are interdigitated such that each of the plurality of drive lines from each of the plurality of drive electrode groups is disposed adjacent to one of the plurality of drive lines from another one of the plurality of drive electrode groups.