Moisture management

• US 10,126,892 B2
• Filed: 03/31/2016
• Issued: 11/13/2018
• Est. Priority Date: 03/16/2016
• Status: Active Grant

• Current Assignee: Synaptics Incorporated
• Original Assignee: Synaptics Incorporated
• Inventors: Chintalapoodi, Prakriti
• Primary Examiner(s): Mehmood, Jennifer
• Assistant Examiner(s): Azongha, Sardis F
• Application Number:
  US15/087,653
• Publication Number:
  US 20170269729A1
• Time in Patent Office: 957 Days
• CPC Class Codes: G01N 27/223 for determining moisture content, e.g. humidity rain detectors on vehicle windows B60S1/0825
• CPC Class Codes: G06F 3/04186 Touch location disambiguation
• CPC Class Codes: G06F 3/044 by capacitive means

Abstract

A method for moisture detection includes obtaining absolute capacitive sensor data, and processing circuitry, determining a contiguous region in a capacitive image generated based on the absolute capacitive sensor data, determining a concavity parameter of the contiguous region, and detecting a presence of moisture based at least in part on the concavity parameter. The method further includes operating based on a presence of moisture.

Claims

1. A processing system for moisture detection comprising:

sensor circuitry for obtaining absolute capacitive sensor data; and

processing circuitry configured to;

determine a contiguous region in a capacitive image generated based on the absolute capacitive sensor data,

determine a concavity parameter of the contiguous region, wherein the concavity parameter is based on a two-dimensional geometry of the contiguous region in the capacitive image, determined in a plane parallel to an input surface of a sensing region from which the absolute capacitive sensor data were obtained, with a concavity described by the concavity parameter being assessed in the plane, in the capacitive image,

detect a presence of moisture based at least in part on the concavity parameter, and

operate based on the presence of moisture.

2. The processing system of claim 1, wherein the processing circuitry is further configured to:

determine a peak value of the contiguous region;

determine a number of contiguous values that are greater than a threshold value and comprise the peak value; and

determine a peak size of the peak based on the number of contiguous values,

wherein detecting the presence of moisture is further based on the peak size.

3. The processing system of claim 1, wherein the processing circuitry is further configured to:

determine a variability indicator in a number of peaks of the contiguous region over time,

wherein detecting the presence of moisture is further based on the variability indicator.

4. The processing system of claim 1, wherein operating based on the presence of moisture comprises:

mitigating effects of moisture in the contiguous region.

5. The processing system of claim 4, wherein mitigating effects of moisture comprises:

determining a distance between each pixel in the contiguous region to a peak value of the contiguous region;

reducing a size of the contiguous region based on the distance to obtain a revised contiguous region;

determining positional information of an input object using the revised contiguous region.

6. The processing system of claim 4, wherein mitigating effects of moisture comprises:

eroding a plurality of original pixels of the contiguous region to obtain a plurality of remaining pixels;

dilating the plurality of remaining pixels to obtain a revised contiguous region; and

determining positional information of an input object using the revised contiguous region.

7. The processing system of claim 1, wherein the sensor circuitry is configured to connect to a plurality of sensor electrodes disposed in a matrix array, wherein each sensor electrode of the plurality of sensor electrodes represents a pixel in the capacitive image, and wherein the sensor circuitry is configured to obtain the absolute capacitive sensor data using the plurality of sensor electrodes.

8. A method for moisture detection comprising:

obtaining absolute capacitive sensor data;

determining a contiguous region in a capacitive image generated based on the absolute capacitive sensor data;

determining a concavity parameter of the contiguous region, wherein the concavity parameter is based on a two-dimensional geometry of the contiguous region in the capacitive image, determined in a plane parallel to an input surface of a sensing region from which the absolute capacitive sensor data were obtained, with a concavity described by the concavity parameter being assessed in the plane, in the capacitive image;

detecting a presence of moisture based at least in part on the concavity parameter; and

operating based on the presence of moisture.

9. The method of claim 8, further comprising:

determining a peak value of the contiguous region;

determining a number of contiguous values that are greater than a threshold value and comprise the peak value; and

determining a peak size of the peak based on the number of contiguous values,

wherein detecting the presence of moisture is further based on the peak size.

10. The method of claim 8, further comprising:

determining a variability indicator in a number of peaks of the contiguous region over time,

wherein detecting the presence of moisture is further based on the variability indicator.

11. The method of claim 8, wherein operating based on the presence of moisture comprises:

mitigating effects of moisture in the contiguous region.

12. The method of claim 11, wherein mitigating effects of moisture comprises:

determining a distance between each pixel in the contiguous region to a peak value of the contiguous region;

reducing a size of the contiguous region based on the distance to obtain a revised contiguous region;

determining positional information of an input object using the revised contiguous region.

13. The method of claim 11, wherein mitigating effects of moisture comprises:

eroding a plurality of original pixels of the contiguous region to obtain a plurality of remaining pixels;

dilating the plurality of remaining pixels to obtain a revised contiguous region; and

determining positional information of an input object using the revised contiguous region.

14. The method of claim 8, wherein operating based on the presence of moisture comprises:

reporting the presence of moisture in the contiguous region.

15. The method of claim 8, wherein the absolute capacitive sensor data are obtained from sensor circuitry, configured to be connected to a plurality of sensor electrodes disposed in a matrix array, and wherein each sensor electrode of the plurality of sensor electrodes represents a pixel in the capacitive image, and wherein the sensor circuitry is configured to obtain the absolute capacitive sensor data using the plurality of sensor electrodes.

16. An input device for moisture detection comprising:

sensor electrodes for obtaining absolute capacitive sensor data; and

a processing system configured to;

determine a contiguous region in a capacitive image generated based on the absolute capacitive sensor data,

determine a concavity parameter of the contiguous region, wherein the concavity parameter is based on a two-dimensional geometry of the contiguous region in the capacitive image, determined in a plane parallel to an input surface of the input device, with a concavity described by the concavity parameter being assessed in the plane, in the capacitive image,

detect a presence of moisture based at least in part on the concavity parameter, and

operate based on the presence of moisture.

17. The input device of claim 16, wherein the processing system is further configured to:

determine a peak value of the contiguous region;

determine a number of contiguous values that are greater than a threshold value and comprise the peak value; and

determine a peak size of the peak based on the number of contiguous values,

wherein detecting the presence of moisture is further based on the peak size.

18. The input device of claim 16, wherein the processing system is further configured to:

determine a variability indicator in a number of peaks of the contiguous region over time,

wherein detecting the presence of moisture is further based on the variability indicator.

19. A processing system for moisture detection comprising:

sensor circuitry for obtaining absolute capacitive sensor data; and

processing circuitry configured to;

determine a contiguous region in a capacitive image generated by the absolute capacitive sensor data;

determine a concavity parameter of the contiguous region;

detect, based on a secondary indicator, an absence of moisture even when the concavity parameter indicates a presence of moisture; and

determine a presence of at least two input objects based on the contiguous region, the concavity parameter, and the absence of moisture.

20. A method for moisture detection comprising:

obtaining absolute capacitive sensor data;

determining a contiguous region in a capacitive image generated by the absolute capacitive sensor data;

determining a concavity parameter of the contiguous region;

detecting, based on a secondary indicator, an absence of moisture even when the concavity parameter indicates a presence of moisture; and

determining a presence of at least two input objects based on the contiguous region, the concavity parameter, and the absence of moisture.