| 摘要 |
<p>PURPOSE:To simplify a manufacturing process, and to attain the operation stable over a long period of time by simplifying a circuit, and making a position indicator needless to be adjusted, in a wireless position input device. CONSTITUTION:The position indicator 5 is provided with a resonance circuit. A first and a second scanning circuits 21, 22 select successively a first and a second sense line groups S1, S2. These first and second scanning circuits 21, 22 are connected to the input/output of an amplifier circuit 3a. An AGC circuit 9 controls the amplification degree of the amplifier circuit 3a by an input signal 102. When the position indicator 5 approaches the sense line groups S1, S2, a positive feedback loop circuit is constituted of these and the amplifier circuit 3a, and an oscillation signal 101 is generated. Since the amplitude of the oscillation signal has the indicated position information of the position indicator 5, a position detecting means 6 inputs this, and calculates the indicated position.</p> |
