Patent ID: 7804490

Claim:
A method for gesture detection on a touchpad, comprising the steps of: a. verifying that an object touches on the touchpad, including: monitoring a sensed value on the touchpad; monitoring a variation of the sensed value when the sensed value is greater than a threshold; and determining that the object touches on the touchpad if the sensed value remains greater than the threshold within a first reference time interval and maintains a continuously increasing trend during the first reference time interval; b. determining the movement and direction responsive to a variation of the sensed value of the object on the touchpad; the direction that the object moves on the touch pad from a reference position if, during a third reference time interval, the sensed value maintains a continuously increasing trend at points on the touchpad offset from the reference position in a first direction and a continuously decreasing trend at points on the touchpad offset from the reference position in a second direction opposite to the first direction; c. verifying that the object leaves the touchpad if the object is determined not to move on the touchpad in step b; d. counting a departure time after the object leaves the touchpad; and e. producing a gesture signal after the departure time reaches a second reference time interval; wherein the increasing and decreasing trends are characterized by the calculated difference between a present and a subsequent sensed value.