Method and apparatus for improving the measurement of the timing of touches of a touch screen

An apparatus for determining a time at which a user touched a touch screen of an electronic device, the apparatus comprising:

• a processing unit configured to:
• obtain a touch signal generated by the touch screen during a first time period, the touch signal indicating when the user touched the touch screen during the first time period;
• obtain a sensor signal generated by a first sensor for at least the first time period, the sensor signal comprising a first signal component corresponding to a measurement by the first sensor of the user making contact with the touch screen;
• use the touch signal to identify a time window in the sensor signal containing the first signal component to generate a windowed sensor signal, wherein the obtained touch signal is used to identify a window of a predetermined width within the first time period, the predetermined width being shorter than the first time period and corresponding to a predetermined timing uncertainty for the touch signal;
• and
• process the windowed sensor signal to determine the timing of the first signal component within the windowed sensor signal.

An apparatus for determining a time at which a user touched a touch screen of an electronic device, the apparatus comprising:

• a processing unit configured to:
• obtain a touch signal generated by the touch screen during a first time period, the touch signal indicating when the user touched the touch screen during the first time period;
• obtain a sensor signal generated by a first sensor for at least the first time period, the sensor signal comprising a first signal component corresponding to a measurement by the first sensor of the user making contact with the touch screen;
• use the touch signal to identify a time window in the sensor signal containing the first signal component to generate a windowed sensor signal, wherein the obtained touch signal is used to identify a window of a predetermined width within the first time period, the predetermined width being shorter than the first time period and corresponding to a predetermined timing uncertainty for the touch signal;
• process the windowed sensor signal to determine the timing of the first signal component within the windowed sensor signal;
• determine a signal processing delay based on a comparison of (i) the determined timing of the first signal component within the windowed sensor signal and (ii) the timing of the touch signal;
• and determine, using the determined signal processing delay, the time at which the user touched the touch screen.