| 摘要 |
<p>PURPOSE:To perform an accurate detection of coordinates, by storing the impedance to compensate the variance of floating capacities of parallel electrode lines in X and Y directions which are provided in response to the coordinate position to be detected and then selecting and applying the impedance to each electrode line. CONSTITUTION:Electrodes Xn and Yn of a detecting panel PN are selected successively by a touch electrode changeover switch 3 consisting of an analog multiplexer and then connected to a resonance circuit RC at a touch detecting part 1. The switches (not shown in the diagram) are connected to the electrodes Xn and Yn, respectively. The electrode lines excluding that selected by the switch 3 are grounded. When a touch electrode is selected by the switch 3, a memory 6 selects switches S1-S8 corresponding to the selected touch electrode and connects compensating capacities C1-C8 to compensate the variance of floating capacities of the electrodes Xn and Yn. As a result, an even level is obtained for the detection output of the part 1 to ensure an accurate detection of coordinates.</p> |
