Baseline management with large input object detection

Patent metadata

Field	Value
Publication number	US-9569029-B2
Application number	US-201514625306-A
Country	US
Kind code	B2
Filing date	Feb 18, 2015
Priority date	Feb 18, 2015
Publication date	Feb 14, 2017
Grant date	Feb 14, 2017

Abstract

A method for face detection management includes determining, for a first time, a presence of an input object in a sensing region of a capacitance input device. The presence is determined for the first time using a first baseline, and the input object satisfies a size threshold. The method further includes suppressing a reporting of capacitance input device during a predefined time period based on the presence of the input object, determining a disabled state of a display of a host, wherein the disabled state is in response to determining the presence of the input object for the first time, and determining, in response to an elapse of the predefined time period and for a second time, an absence of the input object in the sensing region. The absence of the input object is determined for the second time using a second baseline to account for the disabled state of the display. The method further includes performing an action based on determining the absence of the input object.

First claim

What is claimed is:

1. A method for face detection management, the method comprising:
determining, for a first time, a presence of an input object in a sensing region of a capacitance input device,
wherein the presence is determined for the first time using a first baseline, and
wherein the input object satisfies a size threshold;

suppressing a reporting of capacitance input device during a predefined time period based on the presence of the input object;
determining a disabled state of a display of a host, wherein the disabled state is in response to determining the presence of the input object for the first time;
determining, in response to an elapse of the predefined time period and for a second time, an absence of the input object in the sensing region, wherein the absence of the input object is determined for the second time using a second baseline to account for the disabled state of the display;
performing an action based on determining the absence of the input object.

2. The method of claim 1 , wherein the action comprises reporting the absence of the input object.

3. The method of claim 1 , wherein the action comprises enabling the display of the capacitance input device.

4. The method of claim 1 , wherein suppressing the reporting comprises ignoring each report generated by the capacitance input device during the predefined time period.

5. The method of claim 1 , wherein suppressing the reporting comprises failing to report positional information to the host during the predefined time period.

6. The method of claim 1 , wherein determining the disabled state of the display comprises disabling the display.

7. The method of claim 1 , wherein determining the disabled state of the display comprises reading a register corresponding to the display.

8. The method of claim 1 , further comprising:
prior to determining the absence of the input object in the sensing region:
determining, after the elapse of the predefined time period and for a threshold number of times, the presence of the input object in the sensing region, wherein the presence of the input object is determined for the threshold number of times using the second baseline,
wherein the display is continually disabled based on the presence of the input object being determined for the threshold number of times.

9. A processing system for capacitance sensing of a capacitive input device, comprising:
a sensor module comprising sensor circuitry configured to be coupled to a plurality of sensor electrodes, the sensor module configured to generate sensing signals received with the plurality of sensor electrodes; and
determination circuitry connected to the plurality of sensor electrodes and configured to:
obtain a profile from the sensing signals,
determine, for a first time, a presence of an input object in a sensing region using the profile,
wherein the presence is determined for the first time using a first baseline, and
wherein the input object satisfies a size threshold,

suppress a reporting of the capacitance input device during a predefined time period based on the presence of the input object,
determine a disabled state of a display of a host, wherein the disabled state is in response to determining the presence of the input object for the first time,
change, in response to the disabled state of the display, the first baseline to a second baseline to account for the disabled state of the display,
determine, in response to an elapse of the predefined time period and for a second time, an absence of the input object in the sensing region, wherein the absence of the input object is determined for the second time using the second baseline, and
issue a report to the host based on determining the absence of the input object.

10. The processing system of claim 9 , wherein the profile is an unfiltered profile and wherein the determination circuitry is further configured to:
determine a first size of the input object using the unfiltered profile;
determine that the first size fails to satisfy an unfiltered threshold;
filter the unfiltered profile to obtain a filtered profile;
determine a second size of the input object using the filtered profile; and
determine that the second size satisfies a filtered threshold,
wherein the presence of the input object is determined based on the second size satisfying the filtered threshold.

11. The processing system of claim 10 , wherein the determination circuitry is further configured to:
determine a sub-region of the sensing region comprising the input object,
wherein the presence of the input object is further determined based on the sub-region being within a sensitive region of the sensing region.

12. The processing system of claim 10 , wherein the determination circuitry is further configured to:
determine that the input object comprises a flat surface facing the sensing region,
wherein the presence of the input object is further determined based on the input object comprising the flat surface.

13. The processing system of claim 9 , wherein the profile is an unfiltered profile and wherein the determination circuitry is further configured to:
determine a size of the input object using the unfiltered profile; and
determine that the size satisfies an unfiltered threshold,
wherein the presence of the input object is determined based on the size satisfying the unfiltered threshold.

14. The processing system of claim 9 , wherein the determination circuitry is further configured to:
determine, from the sensing signals, a number of a plurality of pixels saturated by the input object,
wherein the presence of the input object is determined based on the number of the plurality of pixels saturated by the input object satisfying a saturation threshold.

15. The processing system of claim 9 , wherein the first baseline comprises a first baseline value for each of a plurality of channels, wherein changing the first baseline to a second baseline comprises changing the first baseline value for each of the plurality of channels by heterogeneous amounts to generate a second baseline value for each of the plurality of channels.

16. The processing system of claim 9 , wherein the determination circuitry is further configured to:
prior to determining the absence of the input object in the sensing region:
determine, after the elapse of the predefined time period and for a threshold number of times, the presence of the input object in the sensing region, wherein the presence of the input object is determined for the threshold number of times using the second baseline,
wherein the display is continually disabled based on the presence of the input object being determined for the threshold number of times.

17. An input device comprising:
a plurality of sensor electrodes configured to generate sensing signals; and
processing circuitry connected to the plurality of sensor electrodes and configured to:
obtain a profile from the sensing signals,
determine, for a first time, a presence of an input object in a sensing region using the profile,
wherein the presence is determined for the first time using a first baseline, and
wherein the input object satisfies a size threshold,

suppress a reporting of the input device during a predefined time period based on the presence of the input object,
determine a disabled state of a display of a host, wherein the disabled state is in response to determining the presence of the input object for the first time,
change, in response to the disabled state of the display, the first baseline to a second basel

Assignees

• Synaptics Inc

Inventors

• Wang Ying
• Moore Tyler
• Mahalingam Vijay Venkatesh
• Solven Derek
• Peng Earl
• Fotopoulos Nickolas

Classifications

• G06K9/00234

  Physics · mapped topic

• G06K9/00228

  Physics · mapped topic

• G06K9/00993

  Physics · mapped topic

• G06F3/0416 Primary

  Control or interface arrangements specially adapted for digitisers · CPC title

• G06F3/044

  by capacitive means · CPC title