Wireless coordinate reading system

Abstract

A wireless coordinate reading system composed of: a plurality of sense lines disposed in parallel with one another and equispaced from one another in a coordinate detecting direction; first and second excitation lines each composed of a plurality of conductors connected together in series and arranged in a zigzag pattern, the conductors being disposed in parallel with one another and equispaced from one another and extending in a direction to intersect the sense lines at right angles thereto; an excitation signal generating circuit for producing an AC signal; an excitation selecting circuit connected for connecting a selected one or the excitation lines to the excitation signal generating circuit; a scanning circuit connected for selecting successive ones of the sense lines in sequence; a wireless coordinate indicator containing components forming a resonator constructed to resonate with the AC signal generated by the excitation signal generating circuit, the indicator being positionable relative to the sense lines in order for the resonator to be electromagnetically coupled with the sense lines; and a signal processing and control circuit connected to evaluate signals induced in each sense line as the selecting and scanning circuits are operated to select successive sense lines.