Transparent overlay input device

An automotive display system, comprising:

• an automotive display panel for providing at least one of motor vehicle operating information and motor vehicle accessory information to a system user;
• and
• a transparent overlay input device attached to the automotive display panel such that graphics displayed by the panel are visible to the user through the device, the device including:
• a transparent non-conductive substrate forming an outer surface;
• a plurality of transparent independent conductive electrode pairs formed on the outer surface of the substrate, wherein each of the electrode pairs forms a discrete proximity sensitive region at a predetermined location on said outer surface and includes a first electrode that receives an input signal and a second electrode that provides an output signal, and wherein the first and second electrodes of each of the electrode pairs are disposed adjacent to one another and are capacitively coupled wherein the capacitance of each of the electrode pairs changes when a conductive member is located near a given one of the electrode pairs and wherein each of the electrode pairs are positioned on said outer surface to register with an associated graphic displayed on said display panel;
• and
• a first transparent non-conductive cover formed on the outer surface of the substrate over the transparent electrode pairs.

A transparent overlay input device adapted to overlay a system display panel visually displaying system function related graphics to a system user through said transparent overlay input device, such overlay input device, comprising:

• a transparent non-conductive substrate, said substrate forming an inner surface adapted for affixation to a display panel and an outer surface;
• a plurality of transparent independent conductive electrode pairs formed on the outer surface of the substrate, wherein each of the electrode pairs forms a discrete proximity sensitive region at a predetermined location on said outer surface and includes a first electrode that receives an input signal and a second electrode that provides an output signal, and wherein the first and second electrodes of each of the electrode pairs are disposed adjacent to one another and are capacitively coupled wherein the capacitance of each of the electrode pairs changes when a conductive member is located near a given one of the electrode pairs and wherein each of the electrode pairs are positioned on said outer surface to register with an associated graphic displayed on said display panel;
• a first transparent non-conductive cover formed on the outer surface of the substrate over the transparent electrode pairs;
• a signal source for providing the input signal to the first electrodes;
• and
• a phase sensitive detector for receiving the output signal from the second electrodes, wherein a reference input of the detector receives a reference signal from the signal source and an output of the detector provides an indication when the conductive member is located near one of the electrode pairs.