Method of reproducing graphic material on an intaglio form
AssigneeSimom S.A.
InventorsPaul Pfau, Thomas E. Fausel, Arthur Grunder
Life of this patent
Estimating the term…
Abstract
Copy to be transferred to an intaglio form for printing is first photolithographically reproduced as a basic discontinuous-tone image which is then photoelectrically scanned and converted into a dot pattern by computerized engraving of an intaglio-printing surface. The engraving may be carried out mechanically or by inscribing the dot pattern on a film with the aid of a laser and then projecting it onto a pigment carrier to produce a latent image upon which a blurred halftone replica of the basic image is superimposed to extend the tonal range by selectively deepening the pits subsequently etched into the printing surface.
Claims5
A method of reproducing copy on a printing surface, comprising the steps of:
- preparing a basic planographic halftone image from the copy to be reproduced, said basic image being divided into a multiplicity of disjointed elemental areas of different tonal values;
- photoelectrically scanning said basic image to generate a train of analog pulses varying in amplitude with the tonal values of said elemental areas;
- transforming said analog pulses into binary pulse codes;
- sweeping a laser beam, modulated by said binary pulse codes, across a photosensitive film to form an intermediate dot pattern thereon;
- projecting the dot pattern from said film onto a photosensitive pigment carrier to produce thereon a latent image forming a masking layer upon development of said carrier;
- and
- etching said printing surface through said masking layer, thereby producing an array of dots conforming to said pattern.
Dependencies are inferred from the claim text.