of the operation and control of the system can be seen for purposes of clarity only a single touch panel 100 is shown and described the capability of attaching a plurality of similar touch panels is indicated by the additional emitter and detector selection control signal lines 128 130 exiting to touch panels 2 n and the additional analog signal data lines 124 126 entering the analog to digital converter adc 112 in the computer 110 in this case an analog multiplexor or multiple adc 39 s would have to be used the computer 110 generates emitter and detector selection control signals in the multiplex control logic 116 and transmits them on lines 120 to multiplexors 106 108 mpx in touch panel 100 under control of the emitter and detector selection control signals the multiplexors 106 108 selectively activate the emitters 102 and detectors 104 in the frame 140 of touch panel 100 thereby creating an energy matrix the detectors 104 produce an analog signal the analog signal varies depending on the presence or absence of a stylus 144 in the beam path 142 of the emitter detector pair selected by the multiplexors 106 108 from the emitters 102 and detectors 104 the multiplexor 108 controls the outputting of the analog signal data on line 122 to the adc 112 in the computer 110 the adc 112 converts the analog signal data on.