| 摘要 |
<p>PURPOSE:To accurately detect the coordinate positions of many points even if they are designated simultaneously on a display screen by changing the crossing angle of optical paths to detect the interruption of input of a light receiving element. CONSTITUTION:An X address to which an input is interrupted is stored for a pair of light emitting and light receiving elements set at the X axis side. Then a Y address to which an input is interrupted is stored for a pair of light emitting and receiving elements set at the Y axis side. In order to specify a genuine designated point from said address points, an oblique scan is carried out to check whether the light reception input is interrupted or not. If so, both light emitting and receiving addresses are stored in the form of a scan address table. Then it is checked whether or not any address is overlapping the combination of those light emitting and receiving addresses detected by said oblique scan. If such an address exists, another oblique scan is carried out at another angle. Based on this scan result, a real address is specified.</p> |
