| 摘要 |
<p>PURPOSE:To improve the operability of an input part by omitting a lead wire used to an electromagnetic handwritten information input device (electromagnetic pen). CONSTITUTION:When a switch 8i is turned on by an instruction received from an arithmetic control part 11, a drive current flows to a driving loop 2Li from a driving source 7 and a magnetic flux phi is generated. This flux phi interlinks an input pen 5. Then the electromagnetic energy generated from the coil 2Li is stored in a coil L. When the pen 5 touches the surface of a substrate 4, a switch 12 is turned on. Then the resonance frequency of a resonance circuit of the pen 5 has a slight deviation since a capacitor C1 is connected in parallel to a capacitor C2. The deviated signal is taken into the part 11 through a detecting coil 4Li, a switch 9i and an amplifier 10. Thus a pen-down signal is obtained.</p> |
