| 摘要 |
<p>PURPOSE:To use one light pen in common with a plurality of display devices, by running electron beams for light pen detection through the shifted timing on a plurality of screens. CONSTITUTION:A light pen switch is depressed by pushing a light a light pen 4 on a CRT screen of a display section 13 and a signal LPS is produced. The LPS is inputted to two sets of display devices 1, 2. One makes start to an address counter 11 without delay and the other makes start to an address counter 21 via a delay circuit 26. As a result, at the device receiving the LPS first, electron beams for light pen detection run. If the depressed position of a light pen can not be detected, electron beams run at the next device.</p> |
