Touch sensing method

Abstract

This disclosure provides a touch sensing method. The touch sensing method includes the following steps: Performing reference touch sensing to record reference parameters. The reference touch sensing includes sensing reference noise and a scan signal. The scan signal is configured to sense changes in the capacitance of a touch panel. Furthermore, the reference parameters include the phase difference between the reference noise and the scan signal. Based on the reference parameters, the phase of the scan signal is adjusted, and touch sensing for the next frame is performed.

Claims

1. A touch sensing method, comprising: A reference touch sensing is performed to record reference parameters, wherein the reference touch sensing includes sensing reference noise and sensing the change in capacitance of the touch panel based on a scan signal, and the reference parameters include the phase difference between the reference noise and the scan signal; and based on the reference parameters, in the next frame after the reference touch sensing, the noise of the next frame is first sensed, the phase difference between the noise of the next frame and the reference noise is compared to determine the required offset of the scan signal of the next frame, and the phase of the scan signal is adjusted based on the offset, and the touch scan of the next frame is performed based on the phase-adjusted scan signal.

2. The touch sensing method as claimed in claim 1, wherein the reference noise is the noise with the maximum energy value at each frequency.

3. The touch sensing method as described in claim 1 further includes: Determine whether the activation conditions have been met, wherein the activation conditions include noise with a maximum energy value being a single-frequency signal or a signal with a fixed period; And in response to the activation condition being met, the baseline touch sensing is performed.

4. The touch sensing method as described in claim 1 further includes: Determine whether the startup conditions have been met, wherein the startup conditions include the activation of a function with a specific operating frequency; And in response to the activation condition being met, the baseline touch sensing is performed.

5. The touch sensing method as claimed in claim 1, wherein the reference noise is a single-frequency signal or a signal with a fixed period.

6. The touch sensing method as claimed in claim 1, wherein the scan signal is a square wave having a scan period, and at least one of the reference noise and the noise of the next frame is a sine wave having a noise period.

7. The touch sensing method as described in claim 1 further includes: The phase of the scan signal is adjusted to generate an adjusted scan signal, wherein the start time of the original scan signal is different from the start time of the adjusted scan signal.

8. The touch sensing method as described in claim 1, further comprising: The phase of the scan signal is adjusted to generate an adjusted scan signal, wherein the first rising edge of the scan signal in the reference touch sensing forms a reference intersection with the reference noise, and the first rising edge of the adjusted scan signal forms an intersection with the noise of the next frame, wherein the phase of the noise of the next frame at the intersection is the same as the phase of the reference noise at the reference intersection.

9. The touch sensing method as described in claim 1, further comprising: The phase of the scan signal is adjusted to generate an adjusted scan signal, wherein the phase relationship between the reference noise and the scan signal in the reference touch sensing is the same as the phase relationship between the adjusted scan signal and the noise in the next frame.

10. The touch sensing method as described in claim 1, further comprising: After performing a touch scan of the next frame based on the phase-adjusted scan signal, the touch system removes the fixed value caused by the noise of the next frame from the sensing value obtained from the touch scan of the next frame to generate a noise-removed touch sensing value.

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