Heidelberger Druckmaschinen Ag

Gerhard Vogler

Stefan Schmidt

Norbert Liebig

Rainer Müllenhagen

A method sets up a device for image reproduction on printing plates. The fastening of image reproduction members, their orientation and tolerances, and also tolerances in the positioning of the image reproduction members on a guide or a spindle, lead to mis-positions of the image reproduction members in relation to one another. Offsets of two adjacent image parts may occur. In the method, the printing plate has reproduced on it in the X-direction at least one first pattern which overlaps with the first pattern of an adjacent image reproduction member and/or the printing plate, in each case with a right and a left column, has reproduced on it in the Y-direction in each case at least three spaced-apart second patterns, such that in each case the right column of an image part is at least contiguous to the left column of an adjacent image part.

Method for setting a device for image reproduction on printing plates

A method and a test form for equalizing exposure heads of an exposer recording printing originals onto a recording material with exposure heads, with regard to the area coverage recorded. Each head contains a laser module generating a laser beam and focusing it onto the material. Each head records a recording band, the laser beams sweeping over the recording material in a main scanning direction while the heads are moved along the material in a secondary scanning direction. A test exposure is carried out, in which each head records a test form having test areas and a background area in its recording band. The area coverage recorded of the background area is compared visually with area coverages recorded of test areas of an adjacent test form and, from differences thereof in adjacent test forms, corrective values for the laser power of the laser modules in the exposure heads are calculated.

Growing community of inventors

Munich, Georgia

Gerhard Vogler