| 摘要 |
<p>PURPOSE:To realize the wireless coordinate reader, for which it is not necessary to connect a coordinate indicator and a tablet by a signal line, by calculating the position of setting a coil according to a guide signal caused by the electromagnetic coupling from an exciting loop line through the coil to a detection loop line. CONSTITUTION:Plural loop line groups 1 are provided and an exciting signal transmission circuit 4, exciting scanning circuit 3, detection scanning circuit 2, coordinate indicator 7, signal processing circuit 5 and control circuit 6 are provided. In this case, when this coordinate indicator 7 is set up near two selected loop lines, the indicator 7 is resonated by an exciting signal and the two loop lines are coupled more strongly. The control circuit 6 inputs the amplitude of the guide signal for each loop line from the envelope waveform of this guide signal and calculates a coordinate value by comparatively calculating the amplitude. Thus, the wireless coordinate reader can be realized without necessity for connecting the coordinate indicator 7 and the tablet by the signal line.</p> |
