| 摘要 |
PURPOSE:To read the information of a coordinate position by using both an electric machine converter attached to the standard point on an input board and a detecting pen with piezo-electric pickup. CONSTITUTION:Piezo-electric elements 2 and 3 for driving use are stock to standard points A and B respectively on input board 1. Piezo-electric elements 2 and 3 are driven alternately by pulses generated from driving circuits 4 and 5 respectively and the mechanical vibration is emitted to the input board. when piezo-electric element 2 is driven, longitudinal vibration wave is propagated radially. Distance b between pen position P and standard point A can be obtained by detecting the longitudinal vibration by means of piezo electric pen 7 depressed on input board 1 and measuring the time from pulse driving to detection. Distance (a) can be obtained in the same manner by the pulse driving of piezo-electric element 3. Since the distance C between standard points A and B is already known, the coordinates (X,Y) of pen point P are calculated. |
