发明名称 |
Method and apparatus for monitoring the passage of marks on a web. |
摘要 |
<p>A method and apparatus for monitoring the passage of a mark (13-16) on a web (5). The web (5) is caused to move through a detection station (7) at which at least that portion of the web carrying the mark is illuminated. An image of the mark (13-16) is projected onto a quadrant array (20) of photodetector elements at the detection station (7). The axes (25,26) defined between the elements (21-24) are tranverse to the direction of movement of the web. The time t1, t2 at which substantially equal areas of a mark are projected on either side of the axes is determined which provide an indication of registration of the web.</p> |
申请公布号 |
EP0289206(A1) |
申请公布日期 |
1988.11.02 |
申请号 |
EP19880303575 |
申请日期 |
1988.04.20 |
申请人 |
CROSFIELD ELECTRONICS LIMITED |
发明人 |
GOUCH, MARTIN PHILIP |
分类号 |
B41F33/14;B41F33/00;B41F33/06 |
主分类号 |
B41F33/14 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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