GROUND DETECTION FOR TOUCH SENSITIVE DEVICE

• US 20110012840A1
• Filed: 07/16/2009
• Published: 01/20/2011
• Est. Priority Date: 07/16/2009
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: King, Brian Michael, Leung, Omar, Lammers, Michael, Orchard, John T., Teoman, Deniz, HOTELLING, Steven Porter, Amm, David T.
• Granted Patent: US 9,632,622 B2
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 3/0418 for error correction or compensation, e.g. based on parallax, calibration or alignment
• 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

Ground detection of a touch sensitive device is disclosed. The device can detect its grounded state so that poor grounding can be selectively compensated for in touch signals outputted by the device. The device can include one or more components to monitor certain conditions of the device. The device can analyze the monitored conditions to determine the grounding condition of the device. The device can apply a function to compensate its touch signal outputs if the device determines that it is poorly grounded. Conversely, the device can omit the function if the device determines that it is well grounded.

Claims

1. A touch sensitive device comprising:

at least one device component configured to provide an output indicative of a state of the device;

a touch sensing component configured to sense a touch at the device and to output a touch signal associated with the sensed touch; and

a processor configured to

determine a grounding condition of the device based on at least one of the device component output or the touch sensing component output, and

apply a function to compensate the touch signal if the device is determined to be poorly grounded.

2. The device of claim 1, wherein the device component is at least one of a connector sensor configured to sense a component connection to the device, a resistor detector configured to detect a resistor connection to the device, a motion sensor configured to sense at least one of motion or orientation of the device, a proximity sensor configured to sense a surface proximate to the device, a perimeter sensor configured to sense an object in contact with a perimeter of the device, a property sensor configured to sense a property of an object proximate to the device, or an application indicator configured to indicate what type of application the device executes.

3. The device of claim 2, wherein the processor is configured to determine the grounding condition of the device based on at least one of the component connection, the resistor connection, the device motion, the device orientation, the proximate surface, the perimeter contact, or the executed application.

4. The device of claim 1, wherein the touch sensing component is configured to determine the portion of an object touching the device according to the touch signal.

5. The device of claim 4, wherein the processor is configured to determine the grounding condition of the device based on the determined touching portion of the object.

6. The device of claim 1, wherein the function reduces an error introduced into the touch signal when the device is poorly grounded.

7. The device of claim 1, wherein the processor is configured not to apply the function if the device is well grounded.

8. The device of claim 1 incorporated into at least one of a mobile telephone, a digital media player, or a personal computer.

9. A method comprising:

capturing a touch signal indicative of a touch at a touch sensitive device;

providing at least one parameter value associated with a status of the device;

determining a grounding condition of the device based on the provided parameter value; and

determining an amount of adjustment to the touch signal based on the grounding determination.

10. The method of claim 9, wherein providing the parameter value comprises providing information corresponding to at least one of whether the device is plugged into a wall outlet, whether the device is coupled to a grounded device, or whether the device is in physical contact with a user.

11. The method of claim 9, wherein determining the grounding condition comprises determining whether the parameter value is indicative of a grounded state of the device.

12. The method of claim 9, wherein determining the amount of adjustment comprises determining that no adjustment is required if the device is grounded.

13. The method of claim 9, wherein determining the amount of adjustment comprises determining the extent to which the device is grounded and scaling an adjustment amount for an ungrounded device proportionate to the determined extent.

14. The method of claim 9, comprising adjusting the captured touch signal using the determined amount.

15. A touch sensitive device comprising:

one or more input components;

a touch sensor panel comprising multiple pixels, each pixel configured to output a touch value indicative of a touch event at the device; and

a processor configured to

analyze one or more inputs from the input components,

determine a grounded state of the device based on the analyzed inputs, and

provide a function to selectively compensate the touch value of each pixel in accordance with the determined state.

16. The device of claim 15, wherein the processor is configured to activate the provided function if the determined state corresponds to the device being poorly grounded.

17. The device of claim 15, wherein the processor is configured to activate the provided function if the determined state corresponds to the device being partially grounded and to adjust the provided function in accordance with the level of the partial grounding.

18. The device of claim 15, wherein the processor is configured to deactivate the provided function if the determined state corresponds to the device being well grounded.

19. The device of claim 15, wherein, when the determined state corresponds to the device being poorly grounded or being partially grounded, the processor is configured to activate the provided function to compensate the touch values of the pixels for error introduced by the device into the touch values as a result of the device being poorly grounded or being partially grounded.

20. A portable device comprising:

multiple parameter indicators associated with the device;

logic configured to analyze parameter values provided by the indicators, determine a state of the device based on the analyzed values, and to adjust at least one of output or operation of the device based on the determined state.

21. The device of claim 20, wherein the determined state comprises one of a grounded state and a poorly grounded state and the logic adjusts a touch output of the device based on whether the device is well grounded or poorly grounded.

22. The device of claim 20, wherein the determined state comprises one of the device being proximate to a user and the device not being proximate to the user and the logic adjusts a radiation output of the device based on whether the device is proximate or not proximate to the user.

23. The device of claim 20, wherein the determined state comprises one of the device being active and the device being idle and the logic adjusts power usage of the device based on whether the device is active or idle.

24. The device of claim 20, wherein the device is a touch sensitive device.

25. A method comprising:

checking one or more parameters of a device;

analyzing values of the parameters to determine a present state of the device; and

providing functionality for adjusting the device based on the determined state, the determined state being at least one of a grounded state, an orientation, or a usage of the device.