SENSE ELECTRODE SPINE INTERPOLATION

• US 20110096015A1
• Filed: 10/22/2009
• Published: 04/28/2011
• Est. Priority Date: 10/22/2009
• Status: Active Grant

• Current Assignee: Neodrón Limited (Atlantic IP Services Limited)
• Original Assignee: Atmel Corporation (Microchip Technology Incorporated)
• Inventors: Yilmaz, Esat
• Granted Patent: US 8,797,290 B2
• Time in Patent Office: Days
• US Class Current: 345/174
• 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

An electrode layout for a touchscreen includes multiple sense electrodes. Each sense electrode has multiple spines coupled to each other, including a main spine and at least one spaced apart interpolation spine running in the same direction. The interpolation spine of one sense electrode is positioned adjacent a spaced apart interpolation spine of a neighboring sense electrode to provide interpolated sense electrodes.

Claims

1. A sense electrode layout for a touchscreen, the layout comprising:

multiple sense electrode main spines extending in a first direction;

multiple interpolation sense electrode spines extending in the first direction and coupled to selected main spines and disposed between neighboring main spines.

2. The electrode layout of claim 1 wherein an interpolation spine generates a smaller change in capacitance on touch, approximately one half of the change in capacitance of the main spines.

3. The electrode layout of claim 1 wherein the interpolation spines adjacent other interpolation spines shield each other'"'"'s opposing edges and substantially stop fringe electric fields forming between these opposing edges and the drive electrodes.

4. The electrode layout of claim 1 wherein at least one interpolation spine of one sense electrode is separated from its main spine by the interpolation spine of an adjacent sense electrode.

5. The electrode layout of claim 1 wherein main spines of neighboring sense electrodes are separated by at least 10 mm.

6. The electrode layout of claim 5 wherein interpolation spines are separated from their corresponding main spines by at least 4 mm.

7. The electrode layout of claim 1 wherein the sense electrode main spines and interpolation sense electrode spines are coupled to sense lines at a first end and a second end of the sense electrode layout.

8. The electrode layout of claim 7 wherein the spines coupled at each of the first end and second end of the sense electrode layout result in reduced electrode resistance.

9. The electrode layout of claim 1 wherein selected sense electrode main spines and interpolation sense electrode spines are coupled to sense lines at different ends of the sense electrode layout to avoid crossovers.

10. An electrode layout for a touchscreen, the layout comprising:

multiple longitudinal drive electrodes arranged in a solid fill pattern adjacent to each other and running in a same direction;

multiple sense electrodes separated from and running transverse to the drive electrodes, each sense electrode having multiple spines coupled to each other, wherein at least two sense electrodes each have a main spine with at least one spaced apart interpolation spine running in the same direction, the spaced apart interpolation spine of one sense electrode being adjacent a spaced apart interpolation spine of a neighboring sense electrode.

11. The electrode layout of claim 10 wherein an interpolation spine generates a smaller change in capacitance on touch, approximately one half of the change in capacitance of the main spines.

12. The electrode layout of claim 10 wherein the interpolation spines adjacent other interpolation spines shield each other'"'"'s opposing edges and substantially stop fringe electric fields forming between these opposing edges and the drive electrodes.

13. The electrode layout of claim 10 wherein at least one interpolation spine of one sense electrode is separated from its main spine by the interpolation spine of an adjacent sense electrode.

14. The electrode layout of claim 10 wherein main spines of neighboring sense electrodes are separated by at least 10 mm.

15. The electrode layout of claim 14 wherein interpolation spines are separated from their corresponding main spines by at least 4 mm.

16. The electrode layout of claim 10 wherein the spines are coupled to sense lines at a first end and a second end of the sense electrodes.

17. The electrode layout of claim 16 wherein the spines coupled at the first end and the second end of the sense electrode layout result in reduced electrode resistance.

18. The electrode layout of claim 10 wherein selected spines are coupled to sense lines at different ends of the sense electrode layout to avoid crossovers.

19. The electrode layout of claim 10 wherein the drive electrodes and sense electrodes are separated by a dielectric layer.

20. The electrode layout of claim 10 wherein the drive electrodes and sense electrodes are in the same layer.

21. A method comprising:

forming multiple longitudinal drive electrodes over a display devices, the drive electrodes arranged in a solid fill pattern adjacent to each other and running in a same direction;

forming multiple sense electrodes separated from and running transverse to the drive electrodes, each sense electrode having multiple spines coupled to each other, wherein at least two sense electrodes each have a main spine with at least one interpolation spine running in the same direction, the interpolation spine of one sense electrode being adjacent an interpolation spine of a neighboring sense electrode.

22. The method of claim 21 wherein forming multiple longitudinal drive electrodes includes using a transparent conductive material.

23. The method of claim 22 wherein the conductive material is indium tin oxide.

24. The method of claim 21 wherein forming multiple sense electrodes includes separating central spines of neighboring sense electrodes by at least 10 mm.

25. The method of claim 21 wherein forming multiple sense electrodes includes forming an interpolation spine of a first sense electrode closer to the main spine of a second, neighboring sense electrode.