Capacitive measurement processing for mode changes

• US 9,746,975 B2
• Filed: 03/27/2015
• Issued: 08/29/2017
• Est. Priority Date: 03/27/2015
• Status: Active Grant

• Current Assignee: Synaptics Incorporated
• Original Assignee: Synaptics Incorporated
• Inventors: Chintalapoodi, Prakriti, Fotopoulos, Nickolas, Keppel, Drew
• Primary Examiner(s): Edwards, Carolyn R
• Assistant Examiner(s): Gyawali, Bipin
• Application Number:
  US14/671,907
• Publication Number:
  US 20160282980A1
• Time in Patent Office: 886 Days
• Field of Search: None
• CPC Class Codes: G06F 3/041662 using alternate mutual and self-capacitive scanning
• CPC Class Codes: G06F 3/04186 Touch location disambiguation
• CPC Class Codes: G06F 3/044 by capacitive means

Abstract

Hybrid detection includes determining a first profiles based on multiple capacitive measurements, segmenting the first profiles into one dimensional intervals to obtain multiple segments, determining multiple regions of interest using the segments, and determining a set of contiguous regions based on multiple mutual capacitive measurements. Hybrid detection further includes selecting, from the set of contiguous regions, a set of valid contiguous regions using the regions of interest, and reporting positional information for each contiguous region in the set of valid contiguous regions.

Claims

1. A processing system for hybrid detection comprising:

a sensor module coupled to a plurality of sensor electrodes, and configured to;

drive a first subset of the plurality of sensor electrodes with first transmitter signals, receive, corresponding to the first transmitter signals, first resulting signals from a second subset of the plurality of sensor electrodes,

receive second resulting signals from the second subset while the second subset are driven with modulated signals; and

a determination module configured to;

determine a first plurality of profiles based on the second resulting signals,

segment the first plurality of profiles into one dimensional intervals to obtain a plurality of segments;

determine a plurality of regions of interest using the plurality of segments,

determine a set of contiguous regions based on the first resulting signals,

select, from the set of contiguous regions, a set of valid contiguous regions using the plurality of regions of interest, wherein the determination module is further configured to select the set of valid contiguous regions by;

for each contiguous region in the set of contiguous regions, determining a peak amplitude for the contiguous region to obtain a plurality of peak amplitudes, the peak amplitude being determined from the plurality of mutual capacitive measurements,

determining a threshold amplitude from the plurality of peak amplitudes, and

removing each contiguous region from the set of contiguous regions when the peak amplitude for the contiguous region fails to comply with the threshold amplitude to obtain a set of remaining contiguous regions, the set of remaining contiguous regions comprising the set of valid contiguous regions, and

report positional information for each contiguous region in the set of valid contiguous regions.

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

determine a presence of moisture prior to determining the set of valid contiguous regions.

3. The processing system of claim 1, wherein reporting positional information comprises reporting positional information for at least two contiguous regions.

4. The processing system of claim 1, wherein, after selecting, the set of valid contiguous regions comprises more than two contiguous regions, and wherein the set of valid contiguous regions is reduced to two contiguous regions prior to reporting positional information.

5. The processing system of claim 1, wherein selecting the set of valid contiguous regions comprises:

removing any contiguous regions from the set of contiguous regions lacking a pixel in at least one region of interest in the plurality of regions of interest.

6. The processing system of claim 1, wherein selecting the set of valid contiguous regions comprises:

for each region of interest in the plurality of regions of interest,

determining a number of positive pixels for the region of interest, and

removing the region of interest from the plurality of regions of interest when the number of positive pixels fails to comply with a threshold number to obtain a plurality of remaining regions of interest, and

removing any contiguous regions from the set of contiguous regions lacking a pixel in at least one region of interest in the plurality of remaining regions of interest.

7. The processing system of claim 1, wherein selecting the set of valid contiguous regions comprises:

for each contiguous region in the set of remaining contiguous regions,

determining a prominence of the contiguous region in a region of interest of the plurality of regions of interest, and

removing the contiguous region from the set of remaining contiguous regions when the prominence of the contiguous region fails to comply with a threshold prominence to further obtain the set of remaining contiguous regions.

8. The processing system of claim 1, wherein selecting the set of valid contiguous regions comprising merging contiguous regions coexisting in a same region of interest of the plurality of regions of interest.

9. A method for hybrid detection comprising:

determining a first plurality of profiles based on a plurality of capacitive measurements;

segmenting the first plurality of profiles into one dimensional intervals to obtain a plurality of segments;

determining a plurality of regions of interest using the plurality of segments;

determining a set of contiguous regions based on a plurality of mutual capacitive measurements;

selecting, from the set of contiguous regions, a set of valid contiguous regions using the plurality of regions of interest, wherein selecting the set of valid contiguous regions comprises;

for each contiguous region in the set of contiguous regions, determining a peak amplitude for the contiguous region to obtain a plurality of peak amplitudes, the peak amplitude being determined from the plurality of mutual capacitive measurements,

determining a threshold amplitude from the plurality of peak amplitudes, and

removing each contiguous region from the set of contiguous regions when the peak amplitude for the contiguous region fails to comply with the threshold amplitude to obtain a set of remaining contiguous regions, the set of remaining contiguous regions comprising the set of valid contiguous regions; and

reporting positional information for each contiguous region in the set of valid contiguous regions.

10. The method of claim 9, further comprising:

determining a presence of moisture prior to determining the set of valid contiguous regions.

11. The method of claim 9, wherein reporting positional information comprises reporting positional information for at least two contiguous regions.

12. The method of claim 9, wherein, after selecting, the set of valid contiguous regions comprises more than two contiguous regions, and wherein the set of valid contiguous regions is reduced to two contiguous regions prior to reporting positional information.

13. The method of claim 9, wherein selecting the set of valid contiguous regions comprises:

removing any contiguous regions from the set of contiguous regions lacking a pixel in at least one region of interest in the plurality of regions of interest.

14. The method of claim 9, wherein selecting the set of valid contiguous regions comprises:

for each region of interest in the plurality of regions of interest,

determining a number of positive pixels for the region of interest, and

removing the region of interest from the plurality of regions of interest when the number of positive pixels fails to comply with a threshold number to obtain a plurality of remaining regions of interest, and

removing any contiguous regions from the set of contiguous regions lacking a pixel in at least one region of interest in the plurality of remaining regions of interest.

15. The method of claim 9, wherein selecting the set of valid contiguous regions comprises:

for each contiguous region in the set of remaining contiguous regions,

determining a prominence of the contiguous region in a region of interest of the plurality of regions of interest, and

removing the contiguous region from the set of remaining contiguous regions when the prominence of the contiguous region fails to comply with a threshold prominence to further obtain the set of remaining contiguous regions.

16. The method of claim 9, wherein selecting the set of valid contiguous regions comprising merging contiguous regions coexisting in a same region of interest of the plurality of regions of interest.

17. An input device for hybrid detection comprising:

a plurality of sensor electrodes comprising a first subset and a second subset; and

a processing system configured to;

determine a first plurality of profiles based on a first plurality of resulting signals obtained based on modulated signals,

segment the first plurality of profiles into one dimensional intervals to obtain a plurality of segments;

determine a plurality of regions of interest using the plurality of segments,

determine a set of contiguous regions based on a second plurality resulting signals obtained by transmitting transmitter signals using the first subset and receiving resulting signals using the second subset,

select, from the set of contiguous regions, a set of valid contiguous regions using the plurality of regions of interest, wherein the processing system is further configured to select the set of valid contiguous regions by;

for each contiguous region in the set of contiguous regions, determining a peak amplitude for the contiguous region to obtain a plurality of peak amplitudes, the peak amplitude being determined from the plurality of mutual capacitive measurements,

determining a threshold amplitude from the plurality of peak amplitudes, and

removing each contiguous region from the set of contiguous regions when the peak amplitude for the contiguous region fails to comply with the threshold amplitude to obtain a set of remaining contiguous regions, the set of remaining contiguous regions comprising the set of valid contiguous regions, and

report positional information for each contiguous region in the set of valid contiguous regions.

18. The input device of claim 17, wherein selecting the set of valid contiguous regions comprises reducing the set of contiguous regions according to a plurality of heuristics.