TWO-DIMENSIONAL POSITION SENSOR

摘要

A sensor for determining a position of an object in two dimensions is provided. The sensor comprises a substrate with a sensitive area defined by a pattern of electrodes arranged thereon. The pattern of electrodes comprises four drive electrodes arranged in a two-by-two array and coupled to respective drive channels, and a sense electrode coupled to a sense channel. The sense electrode is arranged so as to extend around the four drive electrodes (i.e. to wholly or partially surround the drive electrodes, for example, so as to extend adjacent to at least three sides of the drive electrodes). The sensor may further comprise a drive unit for applying drive signals to the respective drive electrodes, and a sense unit for measuring sense signals representing a degree of coupling of the drive signals applied to the respective drive electrodes to the sense electrode. Furthermore the sensor may comprise a processing unit for processing the sense signals to determine a position of an object adjacent the sensor. The functionality of the drive channels, the sense channels, and the processing unit may be provided by a suitably programmed microcontroller.