摘要 |
A printed data strip (7) on a substrate (5) is provided including bit encoded information (23) and control information (15, 19, 27, 29) for an optical scanner. The encoded information is in a plurality of parallel, contiguous data lines (11) formed of bits of sequentially-encoded information, the bits being of uniform height and width. The data lines (11) start along a common line and, together, form an information portion (23) of sequentially-encoded data. The data lines (11) are transverse to the longitudinal dimension of the data strip (7). Associated with the encoded information on the printed substrate (5) are printed areas serving preliminarily to align the optical scanner with the data lines (17), and to set contrast levels (17), to maintain alignment during scanning (27, 29), and to set the vertical (19) and horizontal (15) rates of scanning. Means are provided to control and adjust the timing of each scanned data line by the optical scanner during the course of scanning. |