TOUCH PANEL ELECTRODE STRUCTURE FOR USER GROUNDING CORRECTION

• US 20160224189A1
• Filed: 04/12/2016
• Published: 08/04/2016
• Est. Priority Date: 08/16/2013
• Status: Abandoned Application

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: YOUSEFPOR, Marduke, SHAHPARNIA, Shahrooz
• Application Number:
  US15/097,179
• Publication Number:
  US 20160224189A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 2203/04101 2.5D-digitiser, i.e. digitiser detecting the X/Y position of the input means, finger or stylus, also when it does not touch, but is proximate to the digitiser's interaction surface and also measures the distance of the input means within a short range in the Z direction, possibly with a separate measurement setup
• CPC Class Codes: G06F 2203/04107 Shielding in digitiser, i.e. guard or shielding arrangements, mostly for capacitive touchscreens, e.g. driven shields, driven grounds
• CPC Class Codes: G06F 2203/04111 Cross over in capacitive digitiser, i.e. details of structures for connecting electrodes of the sensing pattern where the connections cross each other, e.g. bridge structures comprising an insulating layer, or vias through substrate
• 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 3/041662 using alternate mutual and self-capacitive scanning
• CPC Class Codes: G06F 3/04182 Filtering of noise external to the device and not generated by digitiser components
• CPC Class Codes: G06F 3/04186 Touch location disambiguation
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• 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 3/0448 Details of the electrode shape, e.g. for enhancing the detection of touches, for generating specific electric field shapes, for enhancing display quality

Abstract

A touch panel electrode structure for user grounding correction in a touch panel is disclosed. The electrode structure can include an array of electrodes for sensing a touch at the panel, and multiple jumpers for selectively coupling groups of the electrodes together to form electrode rows and columns that cross each other. In some examples, the array can have a linear configuration and can form the rows and columns by coupling diagonally adjacent electrodes using the jumpers in a zigzag pattern, or the array can have a diamond configuration and can form the rows and columns by coupling linearly adjacent electrodes using the jumpers in a linear pattern. In various examples, each electrode can have a solid structure with a square shape, a reduced area with an outer electrode and a physically separate center electrode, a hollow center, or a solid structure with a hexagonal shape.

Claims

1. A touch sensitive device comprising:

an array of touch node electrodes; and

a processor coupled to the array of touch node electrodes and capable of;

measuring a self-capacitance of a plurality of touch node electrodes; and

measuring a mutual capacitance between a first touch node electrode of the plurality of touch node electrodes and a second touch node electrode of the plurality of touch node electrodes,

wherein measuring the mutual capacitance between the first touch node electrode and the second touch node electrode comprises;

applying a stimulation voltage to the first touch node electrode; and

measuring, at the second touch node electrode, the mutual capacitance between the first touch node electrode and the second touch node electrode.

2. The touch sensitive device of claim 1, wherein the first touch node electrode and the second touch node electrode are disposed diagonally from one another in the array of touch node electrodes.

3. The touch sensitive device of claim 2, wherein the processor is further capable of, while measuring the mutual capacitance between the first touch node electrode and the second touch node electrode, applying a common voltage to a third touch node electrode of the plurality of touch node electrodes and a fourth touch node electrode of the plurality of touch node electrodes;

wherein the third touch node electrode is disposed adjacent to the first touch node electrode in a first dimension and adjacent to the second touch node electrode in a second dimension, and

the fourth touch node electrode is disposed adjacent to the first touch node electrode in the second dimension and adjacent to the second touch node electrode in the first dimension.

4. The touch sensitive device of claim 3, wherein the processor is further capable of:

measuring a mutual capacitance between the third touch node electrode and the fourth touch node electrode, wherein measuring the mutual capacitance between the third touch node electrode and the fourth touch node electrode comprises;

applying the stimulation voltage to the third touch node electrode;

measuring, at the fourth touch node electrode, the mutual capacitance between the third touch node electrode and the fourth touch node electrode; and

applying the common voltage to the first touch node electrode and the second touch node electrode.

5. The touch sensitive device of claim 1, wherein the first touch node electrode is disposed adjacent to the second touch node electrode in the array of touch node electrodes.

6. The touch sensitive device of claim 5, wherein the processor is further capable of:

measuring a second mutual capacitance between the first touch node electrode and the second touch node electrode, wherein measuring the second mutual capacitance between the first touch node electrode and the second touch node electrode comprises;

applying the stimulation voltage to the second touch node electrode; and

measuring, at the first touch node electrode, the second mutual capacitance between the first touch node electrode and the second touch node electrode.

7. The touch sensitive device of claim 1, wherein the processor is further capable of:

while measuring the mutual capacitance between the first touch node electrode and the second touch node electrode, measuring a self-capacitance of the first touch node electrode.

8. The touch sensitive device of claim 7, wherein:

the plurality of touch node electrodes further includes a third touch node electrode and a fourth touch node electrode,

the third touch node electrode is disposed adjacent to the first touch node electrode in a first dimension and adjacent to the second touch node electrode in a second dimension,

the fourth touch node electrode is disposed adjacent to the first touch node electrode in the second dimension and adjacent to the second touch node electrode in the first dimension, and

the processor is further capable of, while measuring the mutual capacitance between the first touch node electrode and the second touch node electrode and the self-capacitance of the first electrode, applying a common voltage to the third touch node electrode and the fourth touch node electrode.

9. The touch sensitive device of claim 7, wherein:

the plurality of touch node electrodes further includes a third touch node electrode and a fourth touch node electrode,

the third touch node electrode is disposed adjacent to the first touch node electrode in a first dimension and adjacent to the second touch node electrode in a second dimension,

the fourth touch node electrode is disposed adjacent to the first touch node electrode in the second dimension and adjacent to the second touch node electrode in the first dimension, and

the processor is further capable of, while measuring the mutual capacitance between the first touch node electrode and the second touch node electrode and the self-capacitance of the first electrode;

applying the stimulation voltage to the third touch node electrode and the fourth touch node electrode; and

concurrently measuring a self-capacitance of the third touch node electrode and a self-capacitance of the fourth touch node electrode.

10. The touch sensitive device of claim 1, wherein the processor is further capable of:

calculating touch signals for the plurality of touch node electrodes based on the measured self-capacitance of the plurality of touch node electrodes and the measured mutual capacitance between the first touch node electrode and the second touch node electrode.

11. The touch sensitive device of claim 10, wherein the processor is further capable of:

determining one or more correction factors based on the measured self-capacitance of the plurality of touch node electrodes and the measured mutual capacitance between the first touch node electrode and the second touch node electrode; and

calculating the touch signals for the plurality of touch node electrodes using the one or more correction factors.

12. A method for determining touch signals at a touch sensitive device including an array of touch node electrodes, the method comprising:

measuring a self-capacitance of a plurality of touch node electrodes; and

measuring a mutual capacitance between a first touch node electrode of the plurality of touch node electrodes and a second touch node electrode of the plurality of touch node electrodes, wherein measuring the mutual capacitance between the first touch node electrode and the second touch node electrode comprises;

applying a stimulation voltage to the first touch node electrode; and

measuring, at the second touch node electrode, the mutual capacitance between the first touch node electrode and the second touch node electrode.

13. The method of claim 12, wherein the first touch node electrode and the second touch node electrode are disposed diagonally from one another in the array of touch node electrodes.

14. The method of claim 13, the method further comprising, while measuring the mutual capacitance between the first touch node electrode and the second touch node electrode, applying a common voltage to a third touch node electrode of the plurality of touch node electrodes and a fourth touch node electrode of the plurality of touch node electrodes;

wherein the third touch node electrode is disposed adjacent to the first touch node electrode in a first dimension and adjacent to the second touch node electrode in a second dimension, and

the fourth touch node electrode is disposed adjacent to the first touch node electrode in the second dimension and adjacent to the second touch node electrode in the first dimension.

15. The method of claim 14, further comprising:

measuring a mutual capacitance between the third touch node electrode and the fourth touch node electrode, wherein measuring the mutual capacitance between the third touch node electrode and the fourth touch node electrode comprises;

applying the stimulation voltage to the third touch node electrode;

measuring, at the fourth touch node electrode, the mutual capacitance between the third touch node electrode and the fourth touch node electrode; and

applying the common voltage to the first touch node electrode and the second touch node electrode.

16. The method of claim 12, wherein the first touch node electrode is disposed adjacent to the second touch node electrode in the array of touch node electrodes.

17. The method of claim 16, further comprising:

measuring a second mutual capacitance between the first touch node electrode and the second touch node electrode, wherein measuring the second mutual capacitance between the first touch node electrode and the second touch node electrode comprises;

applying the stimulation voltage to the second touch node electrode; and

measuring, at the first touch node electrode, the second mutual capacitance between the first touch node electrode and the second touch node electrode.

18. The method of claim 12, further comprising:

while measuring the mutual capacitance between the first touch node electrode and the second touch node electrode, measuring a self-capacitance of the first touch node electrode.

19. The method of claim 12, further comprising:

calculating touch signals for the plurality of touch node electrodes based on the measured self-capacitance of the plurality of touch node electrodes and the measured mutual capacitance between the first touch node electrode and the second touch node electrode.

20. The method of claim 19, further comprising:

determining one or more correction factors based on the measured self-capacitance of the plurality of touch node electrodes and the measured mutual capacitance between the first touch node electrode and the second touch node electrode; and

calculating the touch signals for the plurality of touch node electrodes using the one or more correction factors.

21. A non-transitory computer-readable storage medium having stored thereon instructions for detecting touch signals at a touch sensitive device including an array of touch node sensors, that when executed by a processor cause the processor to perform a method, the method comprising:

measuring a self-capacitance of a plurality of touch node electrodes; and

measuring a mutual capacitance between a first touch electrode of the plurality of touch node electrodes and a second touch node electrode of the plurality of touch node electrodes;

wherein measuring the mutual capacitance between the first touch node electrode and the second touch node electrode comprises;

applying a stimulation voltage to the first touch node electrode; and

measuring, at the second touch node electrode, the mutual capacitance between the first touch node electrode and the second touch node electrode.

22. A method for determining touch signals at a touch sensitive device including an array of touch node electrodes, the method comprising:

measuring first self-capacitances of a plurality of touch node electrodes, wherein the first self-capacitances of the plurality of touch node electrodes are measured simultaneously; and

measuring second self-capacitances of the plurality of touch node electrodes, wherein the second self-capacitances of the plurality of touch node electrodes are measured in a plurality of measurement steps, wherein a portion of the plurality of touch node electrodes are measured during each of the plurality of measurement steps.

23. The method of claim 22, wherein a first measurement step of the plurality of measurement steps comprises:

applying a stimulation voltage to a first touch node electrode of the plurality of touch node electrodes, a second touch node electrode of the plurality of touch node electrodes and a third touch node electrode of the plurality of touch node electrodes;

applying a common voltage to a fourth touch node electrode of the plurality of touch node electrodes; and

measuring a self-capacitance of the first touch node electrode of the plurality of touch node electrodes;

wherein the second touch node electrode is disposed diagonally from the first touch node electrode;

the third touch node electrode is disposed adjacent to the first touch node electrode in a first dimension and adjacent to the second touch node electrode in a second dimension; and

the fourth touch node electrode is disposed adjacent to the first touch node electrode in the second dimension and adjacent to the second touch node electrode in the first dimension.

24. The method of claim 23, wherein a second measurement step of the plurality of measurement steps comprises:

applying a stimulation voltage to the first touch node electrode of the plurality of touch node electrodes, the second touch node electrode of the plurality of touch node electrodes and the fourth touch node electrode of the plurality of touch node electrodes;

applying the common voltage to the third touch node electrode of the plurality of touch node electrodes; and

measuring a self-capacitance of the second touch node electrode of the plurality of touch node electrodes.