| 摘要 |
A conveying mechanism and flexible carrier for transporting a planar printing plate and flexible overlying mask from a flat loading station to a precisely-curved cylindrically-shaped scanning station, and back to the flat loading station, is disclosed. The vacuum carrier used is rigid in one axis and flexible in a second axis, and has a pair of reference strips which define a neutral bending axis for the plate and mask when the latter are wrapped around a pair of precisely machined cylindrical discs. By locating the flexible mask and printing plate outside the neutral axis of bending, both are placed in tension when wrapped around the discs. This maintains uniform contact between the plate and mask and prevents wrinkling of the mask as it overlies the plate. The carrier and discs support the plate and mask within a precise and uniform cylindrical plane for scanning with focussed beams of radiation. The transport mechanism applies a vacuum to the carrier while in its flat position and maintains the vacuum while wrapping the carrier around the spaced cylindrical reference discs. When the image scanning is completed, the transport mechanism returns the carrier to its flat state for unloading of the printing plate and mask.
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