公开(公告)号：EP0136542A3

公开(公告)日：1987-07-22

申请号：EP84110310

申请日：1984-08-30

Applicant: KOLLMORGEN TECHNOLOGIES CORPORATION

Inventor： Benoit, Albert J. ,  Boden, Dudley M. ,  Decker, David G. ,  Kishner, Stanley J. ,  Van Arsdell, Robert D.

IPC: B41F33/00 ,  G01J03/46 ,  G01N21/59

CPC classification number: B41F33/0036 ,  G01J3/46 ,  G01J3/51

Abstract: In a multi-color printing process, measurements of the optical density of two different three-color halftone control areas are used to calculate dot gain and solid density of the cyan, magenta and yellow images. Since no single-color solid control targets are used, control targets may be hidden or camouflaged in a border or logo in the final printed product. The two control targets can consist of light and dark near-neutral gray balance targets. Alternatively, two different three-color half-tone regions of the printed image can be used as control areas, eliminating the need for separate control targets. Densitometers having blue, green and red filters use the two three-color halftone control areas to provide density measurements which are used by a computer to calculate the densities of cyan, magenta and yellow halftone images. The computer then calculates the dot gain and solid density of the process inks, which are displayed to a pressman who can make appropriate adjustments to the printing process.