| 摘要 |
<p>PURPOSE:To detect even the height information of a coordinate indicator by calculating coordinate information based on an induced signal, extracting the amplitude signal of the induced signal induced in a sense line positioned in specified positional relation with a position where the coordinate indicator is placed as a height detection signal, and calculating the height information by using this extracted signal and the coordinate information. CONSTITUTION:In a process to select sequentially a sense line group 3, if the coordinate indicator 9 is placed in the vicinity of the selected sense line, the induced signal is generated in the sense line by an AC magnetic field which the coordinate indicator 9 generates. A control circuit 8 compares and operates the amplitude of these plural induced signals, and obtains the coordinate information. On the other hand, when the amplitude of the induced signal induced in the sense line in the specified positional relation with the coordinate indicator 9 is noticed, this becomes the signal to vary according to the position and the height of the coordinate indicator 9. The control circuit 8 calculates the height information by using this extracted signal and the coordinate information. Thus, the height information can be highly precisely obtained.</p> |
