| 摘要 |
<p>PURPOSE:To obtain a highly reliable tablet detector free from effect by pollution of a photodetecting section and slow changes in disturbance such as temperature change in the perimeter. CONSTITUTION:This apparatus is provided with an optical coupling element 9 to detect a tablet optically, a differentiation circuit 3 to differentiate an output of the optical coupling element and a threshold level generation circuit 4. It is also provided with a comparator circuit 5 to compare an output of the threshold level generation circuit with an output of the differentiation circuit 3 and a conversion circuit 7 to convert an output of the comparator circuit into a pulse having a specified time width.</p> |
