| 摘要 |
<p>The photopolymer plate is exposed from underneath with the negative sheet interposed and with a hinged cover to press the two layers flat. The cover has a ferromagnetic cored backing layer(11) held under the cover with four magnets(9) at the corners. The cover is set slightly open to enable a pre-illumination to sensitise the layer, and with the negative inserted subsequently. The cover is normally held down by a hinged catch(7). The catch also serves to support the cover slightly open, with the head of the catch resting on top of the securing tag(8). In the exposure position the cover and the layers are held together by a suction connection.</p> |
