TOUCH PAD ELECTRODE DESIGN

• US 20090159344A1
• Filed: 12/21/2007
• Published: 06/25/2009
• Est. Priority Date: 12/21/2007
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Hotelling, Steve Porter, Staton, Kenneth Lawrence
• Granted Patent: US 8,358,276 B2
• Time in Patent Office: Days
• US Class Current: 178/18.60
• 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
• CPC Class Codes: G06F 3/047 using sets of wires, e.g. crossed wires

Abstract

A multi-touch capacitive touch sensor panel can be created using a substrate with column and row traces formed on separate layers of the substrate. The column and row traces can include sections extending from a central trace and forming a rectilinear trace pattern with sections of the columns and rows interdigitated with one another. The trace pattern can comprise a plurality of pixels arranged continuously across the sensor panel. In this manner, the sensor panel can provide a linear or near linear response to touches across the touch sensor panel.

Claims

1. A capacitive touch sensor panel, comprising:

a substrate formed from a dielectric material;

a first plurality of traces of conductive material located on a first layer of the substrate, each of the plurality of first traces comprising a first central trace arranged along a first dimension of a two-dimensional coordinate system and a plurality of first trace branches extending perpendicularly from the first central trace in a second dimension of the two-dimensional coordinate system; and

a second plurality of traces of the conductive material located on a second layer of the substrate, each of the second plurality of traces comprising a second central trace arranged along the second dimension and a plurality of second trace branches extending from the second central trace, at least some of the plurality of second trace branches comprising a first extension branch extending perpendicularly along the first dimension from one of the second central traces and at least one second extension branch extending perpendicularly along the second dimension from the first extension branch.

2. The capacitive touch sensor panel of claim 1, wherein portions of the first plurality of traces are interdigitated with portions of the second plurality of traces.

3. The capacitive touch sensor panel of claim 2, wherein the first central trace overlaps at one point with the second central trace.

4. The capacitive touch sensor panel of claim 1, further comprising a computing system that incorporates the sensor panel.

5. The capacitive touch sensor panel of claim 4, further comprising a mobile telephone that incorporates the computing system.

6. The capacitive touch sensor panel of claim 4, further comprising a digital audio player that incorporates the computing system.

7. A capacitive touch sensor panel, comprising:

sense traces formed on a dielectric substrate, each of the sense traces comprising a central sense trace arranged along a first dimension of a two-dimensional coordinate system and a plurality of extension sense traces extending perpendicularly from the central sense trace along a second dimension of the two-dimensional coordinate system; and

drive traces formed on the substrate, each drive trace comprising a central drive trace arranged along the second dimension and a plurality of extension drive traces, wherein at least some of the plurality of extension drive traces include a first section of arranged along the third dimension.

8. The capacitive touch sensor panel of claim 7, wherein at least some of the extension drive traces further include one or more second sections extending perpendicularly from the first section,

9. The capacitive touch sensor panel of claim 7, wherein the sense traces and the driving traces form an interdigitated pattern across a touch sensitive portion of the sensor panel.

10. The capacitive touch sensor panel of claim 9, wherein the central sense trace and the central drive trace overlap at perpendicular angles.

11. The capacitive touch sensor panel of claim 7, wherein the sense traces and the drive traces form a plurality of continuous or substantially continuous pixels.

12. The capacitive touch sensor panel of claim 11, wherein the center of each of the plurality of pixels is where the sense traces and the drive traces overlap.

13. A capacitive touch sensor panel, comprising:

a plurality of rectangular-shaped pixels arranged across a touch sensor panel;

wherein each pixel comprises;

a sensing trace having a central sensing trace arranged along a first dimension of a two-coordinate system and a plurality of sensing braches extending perpendicularly from the central sensing trace; and

a driving trace having a central driving trace arranged along a second dimension of a two-coordinate system and a plurality of driving braches extending from the central driving trace.

14. The capacitive touch sensor panel of claim 13, wherein the central sensing trace and the central driving trace overlap at a central portion of the pixel.

15. The capacitive touch sensor panel of claim 13, wherein at least some of the driving branches include a first section extending perpendicularly from the central driving trace and one or more second sections extending perpendicularly from the first section.

16. The capacitive touch sensor panel of claim 15, wherein the sensing branches and the second sections of the driving branches are interdigitated with one another.

17. The capacitive touch sensor panel of claim 13, wherein first and second sensing branches of the plurality of sensing branches define first and second sides of the pixel, respectively, and first and second driving branches of the plurality of driving branches define third and fourth sides of the pixel, respectively.

18. The capacitive touch sensor panel of claim 13, wherein each of the plurality of sensing branches are spaced apart from the central driving trace and the plurality of driving branches.

19. The capacitive touch sensor panel of claim 13, wherein the plurality of pixels are arranged in a continuous fashion across the touch sensor panel.

20. The capacitive touch sensor of claim 13, wherein the sensing branches are

21. A mobile telephone having a capacitive touch sensor panel, the touch sensor panel comprising:

a substrate formed from a dielectric material;

a first plurality of traces of conductive material located on a first layer of the substrate, each of the plurality of first traces comprising a first central trace arranged along a first dimension of a two-dimensional coordinate system and a plurality of first trace branches extending perpendicularly from the first central trace in a second dimension of the two-dimensional coordinate system; and

a second plurality of traces of the conductive material located on a second layer of the substrate, each of the second plurality of traces comprising a second central trace arranged along the second dimension and a plurality of second trace branches extending from the second central trace, at least some of the plurality of second trace branches comprising a first extension branch extending perpendicularly along the first dimension from one of the second central traces and at least one second extension branch extending perpendicularly along the second dimension from the first extension branch.

22. A digital audio player having a capacitive touch sensor panel, the touch sensor panel comprising:

a substrate formed from a dielectric material;

a first plurality of traces of conductive material located on a first layer of the substrate, each of the plurality of first traces comprising a first central trace arranged along a first dimension of a two-dimensional coordinate system and a plurality of first trace branches extending perpendicularly from the first central trace in a second dimension of the two-dimensional coordinate system; and

a second plurality of traces of the conductive material located on a second layer of the substrate, each of the second plurality of traces comprising a second central trace arranged along the second dimension and a plurality of second trace branches extending from the second central trace, at least some of the plurality of second trace branches comprising a first extension branch extending perpendicularly along the first dimension from one of the second central traces and at least one second extension branch extending perpendicularly along the second dimension from the first extension branch.