Digital Equipment DECcolorwriter 1000, Руководство по обслуживанию

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5-4
DECcolorwriter 1000
5
Theory of Operation
Plain-paper printing
Using the special 4-pass, Plain Paper Transfer Roll, the printer can print on ordinary
Bond paper. In this process, a special coating is applied to the paper in its first pass past
the thermal head. The coating supplies a smooth, flat surface for the yellow, magenta
and cyan wax applied in the following three passes. The coating is applied only to the
portions of the paper where colored wax is to be applied.
Because of the extra pass required for printing on plain paper and the fact that the drum
moves in a slower, half-step mode while laying down the precoat layer, plain-paper print
times are about 10 seconds longer than printing on coated paper with the standard
3-Color transfer roll.
In addition, a greater demand is made on the image processor board's memory for
plain-paper printing. The image processor board must generate a composite bitmap of
the cyan, magenta, and yellow bitmaps. The composite bitmap guides the print engine
on where to apply the precoat on the plain paper.