Heidelberger Druckmaschinen Ag

J&ouml;rg-Achim Fischer

Thomas Jacobsen

Axel Gebhardt

Peter Ressel

Dirk Steinke

J&ouml;rg Suhr

Klaus-G&uuml;nter Leiss

The method is for setting the line width of recorded image lines of a focused image beam in an exposer. The exposure point has a diameter and an area with a non-uniformly distributed power density. The recording material has a first exposure threshold and is exposed with an energy density near a second exposure threshold that is substantially higher than the first exposure threshold. The recording material can be a photopolymer printing plate. The line width of the recorded image lines is determined from the distribution of the power density over the area of the exposure point by integrating the time variation of the power density resulting from the exposure speed of the laser beam. The line width is set, by changing the diameter of the exposure point and/or by the laser power, such that the line width is substantially equal to the line spacing.

Method of setting the image line width in an exposer

A method and a multibeam scanning device for ablation of a surface on a rotating drum by laser engraving with a multi-spot array includes simultaneously emitting laser beams from fiber exits disposed beside one another, dividing up each of the beams, after emerging from the exit in an AOM array having a number of AOMs corresponding to the number of exits, into two or more partial beams modulated independently of one another, imaging the exits with an optical system on the surface, and moving the exits, the AOM array, and the optical system together in a drum axial direction while the surface is scanned by the multi-spot array in a drum circumferential direction to make possible, without increasing the number of fiber lasers, an increase in the number of scanning points of the multi-spot array and a reduction of the space required by the scanning device.

Method and multibeam scanning device for the ablation of flexo printing plates by laser engraving

A method for adjusting variable illumination parameters of a laser imagesetter including laser power, focus adjustment, scan rate, and/or feed rate during the illumination of a photosensitive material, in particular, during illumination tests, includes the steps of reducing the time taken and the workload for determining the correct imagesetter setting by calculating at least some of the illumination parameters, prior to the adjustment, based upon imagesetter-independent characteristic data including material thickness, material sensitivity, material-specific test patterns, and/or material-specific evaluation criteria of the photosensitive material to be illuminated, and, subsequently, adjusting the calculated illumination parameters automatically.

Method for adjusting illumination parameters of a laser imagesetter

A laser diode in a recorder is thermally stabilized. The laser diode is used to produce a light beam, which is modulated by superimposing a basic current and a modulation current derived from an image signal, and exposes a recording material point by point and line by line. Between the exposure periods, wherein in each case one line is exposed, there are return periods, wherein the light beam is guided to the start of the next line, and wherein the laser diode is modulated for the purpose of thermal stabilization. In the return period, the laser diode is modulated with the basic current during a stabilization period, the sum of the modulation times during the exposure period and during the stabilization period being constant. In addition, during the return period, the laser diode can be modulated with a modulation current, which is derived from the inverted image signal from the preceding or the following line.

Method for the thermal stabilization of a laser diode in a recorder

A multi-beam scanning apparatus is provided for use with a recording medium that is located on an at least partially cylindrical inner bearing face of a recording device, in which the bearing face has a cylinder axis. The scanning apparatus includes a scanner unit for scanning the recording medium with at least one exposure beam. The scanner unit includes an acousto-optical element that is either an acousto-optical deflector or an acousto-optical modulator. The scanner unit includes a deflection element that is axially displaceable and rotatable relative to the cylinder axis of the bearing face. The acousto-optical element is mounted to rotate together with the deflection element about the cylinder axis.

Growing community of inventors

Laboe, Germany

Jörg-Achim Fischer

Growing community of inventors

Laboe, Germany

J&ouml;rg-Achim Fischer

Jörg-Achim Fischer