Patent attributes
An apparatus for controlling the position of a screen pointer for an electronic device having a display screen includes a plurality of sensing elements against which a portion of the tip of a human digit may be placed. A controller coupled to each of the sensing elements senses an electrical property at each of the sensing elements. The controller is configured to generate pixel values representing the portion of the tip of the digit placed against the sensing elements based on the sensed electrical property at each of the sensing elements, and generate movement data based on a comparison of successively generated sets of the pixel values. The comparison includes comparing a first one of the sets with at least one pixel shifted version of a second one of the sets. The movement data is indicative of motion of the tip of the digit across the sensing elements.
