US 12,449,932 B2
Method and apparatus for performing partial reads of a touch sensor
Mohammed Zourob, London (CA); Alexander Hunt, Tygelsjö (SE); Andreas Kristensson, Södra Sandby (SE); and Mohammed Abdulaziz, Lund (SE)
Assigned to Telefonaktiebolaget LM Ericsson (publ), Stockholm (SE)
Appl. No. 18/684,134
Filed by Telefonaktiebolaget LM Ericsson (publ), Stockholm (SE)
PCT Filed Aug. 31, 2021, PCT No. PCT/EP2021/074043
§ 371(c)(1), (2) Date Feb. 15, 2024,
PCT Pub. No. WO2023/030613, PCT Pub. Date Mar. 9, 2023.
Prior Publication US 2024/0353954 A1, Oct. 24, 2024
Int. Cl. G06F 3/041 (2006.01)
CPC G06F 3/04166 (2019.05) 13 Claims
OG exemplary drawing
 
1. A method of reading a touch sensor, the method comprising:
identifying a region within a touch surface of the touch sensor to be read;
performing a partial read of the touch sensor by:
obtaining touch-control information from a software application running on a host device that includes the touch sensor, the touch-control information identifying the region to be read and indicating a touch-detection resolution to be used for detecting touch inputs to the identified region;
determining which sensing lines of the touch sensor are involved in the identified region;
choosing how many of the involved sensing lines to excite as chosen sensing lines, and choosing and how many excitation frequencies to use as chosen excitation frequencies for exciting the chosen sensing lines, in dependence on the touch-detection resolution;
exciting the chosen sensing lines using the chosen excitation frequencies to obtain a corresponding sensing signal output from each chosen sensing line, and combining the corresponding sensing signals to obtain a combined sensing signal, with unchosen sensing lines of the touch sensor not being excited;
applying a frequency domain transform to digitized samples of the combined sensing signal, to obtain a sensing value corresponding to each chosen excitation frequency; and
detecting a touch input to the identified region of the touch surface by evaluating the sensing value corresponding to each chosen excitation frequency.