|
A technology in which the image carrier for the gravure printing process is imaged digitally. Electromechanical engraving techniques are used to reproduce the digital image onto the gravure cylinder (image carrier). Digital engraving can produce much finer detail than conventional plating methods. Direct digital electromechanical engraving is the process used to produce most of the plates for the gravure computer-to-plate process. With this process, photographic prints are mounted onto a rotating drum where they are scanned. The scanner records the different densities of the image as analog signals, which are then converted into electrical impulses. The scanner is linked to a diamond stylus, which uses the electrical impulses as a guide to engrave up to 6000 individual depressions per second into the copper gravure cylinder. Gravure cylinders can also be engraved with lasers. The usual gravure cylinder of copper reflects laser beams so a special metal alloy is used to prevent this problem. The laser engraver can etch as many as 70,000 depressions or cells per second into the metal alloy using the digital record.
|