| 摘要 |
<p>PURPOSE:To prevent an elastic wave from being reflected at the edge part of a tablet by installing a material whose acoustic impedance is close to that of a tablet member at the edge part of the tablet for reflection prevention. CONSTITUTION:A vibrator for generating an elastic wave is installed on a coordinate indicator 7 and vibrated while the tip of the coordinate indicator 7 is brought into contact with a tablet substrate 1, so that the elastic wave is generated by the coordinate indicator 7. This elastic wave is inputted to the tablet substrate 1 and propagated in the tablet substrate 1 to reach transducers 3, 4, 5, and 6 for a pickup. The vibrator incorporated in the coordinate indicator 7 uses a material having electrostrictive properties, e.g. barium titanium or zirconia titanium and a burst pulse voltage is applied so as to vibrator the vibrator. The signal of the coordinate reader using the reflection preventing member is small in the number of waves and has a clear waveform and the reflection of the elastic wave on the edge surface of the tablet is absorbed.</p> |
