Patent ID: 8040324

Claim:
A movement detection method for multiple objects on a capacitive touchpad, the method comprising the steps of: detecting sensed values on the touchpad for obtaining a waveform of the sensed values when the touchpad is touched; identifying the waveform for determining a first peak and a second peak thereof; determining a first object and a second object on the touchpad if both of the first peak and the second peak are greater than a first threshold value; dividing the waveform for defining a first region and a second region corresponding to the first object and the second object, respectively; monitoring a first variation in the sensed values within the first region and a second variation in the sensed values within the second region; determining the first object moving on the touchpad if the first variation is greater than a second threshold value; and determining the second object moving on the touchpad if the second variation is greater than a third threshold value; wherein each of the first and second variations is derived directly from the calculated difference between a present sensed value and a subsequent sensed value measured at the same sensed position within a corresponding one of the first and second regions, and the present sensed value and the subsequent sensed value are detected when the touchpad is touched.