KOMBINATION EINES BERUEHRUNGSAKTIVEN UND EINEN GRIFFEL DETEKTIERENDEN SYSTEMS FUER EIN ANZEIGEGERAET

A combined finger touch and stylus detection system is disclosed for use on the viewing surface of the visual display device. Transparent conductors (X1, X2,...X112) arranged in horizontal and vertical grid are supported on a flexible, transparent overlay membrane (20) which is adaptable to a variety of displays. A unique interconnection pattern is provided between the transparent conductors in the array and buses (80,90) which interconnect the conductors with the supporting electronics, whereby a minimum number of bus wires can be employed to service the array conductors and yet both unique finger touch location sensing and unique stylus location sensing can be accomplished. The system includes a control processor (100) which operates on stored program instructions which, in a first embodiment provides for the alternate detection of either finger touch location or stylus location and, in a second embodiment, provides for the simultaneous detection of both finger touch location and stylus location. The resulting system provides the unique function of combined finger touch and stylus detection, is adaptable to a variety of display surfaces, is provided with a structure which is easily manufacturable, and which has an inherent long-term reliability.