Patent ID: 7123027

Claim:
Apparatus, comprising: a first sensor member defining a number of tracks spaced apart from one another, the tracks each including a plurality of capacitive electrode segments, the segments being spaced apart from one another by a corresponding electrically nonconductive gap; a second sensor member including a capacitive electrode, the electrode being spaced apart from the tracks and spanning across the tracks to correspondingly overlap one or more of the segments of each of the tracks; and circuitry including an electrical signal source, logic, and a detection circuit, the source generating a signal pattern over a sequence of time periods, the signal pattern providing a changing voltage to each one of the segments of a respective one of the tracks during a respective one of the time periods, the detection circuit being electrically coupled to the electrode, the electrode being capacitively coupled to the one or more electrode segments of each of the tracks to detect a sequence of emitted signals corresponding to the signal pattern, the logic being responsive to the source and the detection circuit to determine information corresponding to position of the electrode relative to the tracks.