| 摘要 |
The apparatus comprises an optical arrangement which displays longitudinal extending short or long elements of a marking in time sequence on a reading surface. The surface is divided into more than three consecutive sectors and a pulse signal indicating an element of any length is produced if an element is displayed on at least one sector. A code signal indicating a long element is produced if an element is displayed simultaneously on at least two sectors which are separated from each other by at least one other sector. |
