摘要 |
<p>PURPOSE:To simplify a manufacturing process and to enable a stable operation for a long time by simplifying a circuit and making a coordinate indicator non-adjustable in a wireless coordinate reader. CONSTITUTION:A coordinate indicator 8 is equipped with a resonance circuit. A first sense line group S1 and a second sense line group S2 are provided so as not to be directly electromagnetically connected. First and second scanning circuits 1 and 2 successively select the sense line groups. At that time, a pulse generating circuit 6 impresses an excitation pulse signal 103 to the first sense line group S1. When the coordinate indicator 8 approaches the sense line groups, a positive feedback loop circuit is constituted of those sense line groups and an amplifier circuit 3, and an oscillation signal 101 is generated. The amplitude of the oscillation signal 101 has the instructed position information of the coordinate indicator 8, and a coordinate detecting circuit 5 inputs it, and calculates an instructed position.</p> |