| 摘要 |
<p>A circuit arrangement for use with a scanned-beam moving-surface blemish detector uses the detection of leadingand trailing-edges of the surface in each scan to provide in the following scan a margin or margins the separation of which provides a measure of the surface width over which detection can take place without the edges being detected as faults. In a modification the margins are extended to the direction of surfac movement by introducing a minimum width, between leading-and trailing-edge margins, which must exist before fault detection is permitted.</p> |
