Heidelberger Druckmaschinen Ag

Werner Huber

Wolfgang Geissler

Harald Bucher

Bernd Kistler

Manfred Schneider

Helmut Kipphan

Hans Engler

Clemens Rensch

Gerhard Fischer

Gerhard Loeffler

Anton Rodi

Frank Muth

Peter Ehbets

Frank Schumann

Michael Kaiser

Joachim Sonnenschein

Christopher Berti

Peter Elter

Robert Lange

Christopher Riegel

Loris De Vries

Hans-Peter Grossmann

Birgit Plautz

Michael Steinle

Volker Becker

Wolfgang Geiβler

Guenther Uhlig

Stefan Billmaier

Thomas Roos

A method automatically parameterizes error detection of an image inspection system by a computer. The method includes digitizing a reference image in order to determine desired values and subdividing the reference image into homogeneous image regions with few edges, and inhomogeneous image regions with strongly structured image areas and many edges. Lower tolerance values for the homogeneous image regions, and higher tolerance values for the inhomogeneous image regions of the digitized reference image are determined by statistical image analyses. The determined tolerances are assigned to their respective desired values in dependence on a position of the desired values in homogeneous or inhomogeneous image regions. An inspection sensitivity is calculated from desired values and their respective tolerances. The parameters of the image inspection system are set with the aid of the inspection sensitivity configuration of the image inspection system using the parameters.

Method for the automatic parameterization of the error detection of an image inspection system

A color measurement on printed materials produced by a printing press is performed by at least a first color measuring device installed in the printing press and at least a second color measuring device. A signal is output by the first color measuring device in the printing press when the measured color values registered on the printing materials are located within a predefined tolerance limit for a predefined period and that, after the signal has been output, a color measurement on one of the printed materials thus produced is performed with the second color measuring device.

Method for color measurement in printing presses

A method for color control in printing presses having at least one first color measuring instrument and at least one second color measuring instrument, includes registering at least one first inking zone on a printing material with the first color measuring instrument and registering at least one other, second inking zone on the printing material with the second color measuring instrument. In a first step, a color difference between actual colorations of the first and second inking zones is calculated, in a second step, a color difference between an actual coloration of the first inking zone and a desired coloration of the second inking zone is calculated and, in a further step, the calculated color differences are added and supplied to a color control for the second inking zone.

Method for hybrid inline color control for printing presses

A method for registering color measured values on printing materials with a color sensor includes registering the color measured values on the printing materials at different angles of observation of the color sensor. The angular dependence of the color measured values registered on the printing materials at different angles of observation is corrected in a computer.

Method for angle-dependent color value correction

A device for positioning a measuring head above a print substrate includes a display device and a motor-driven positioning device for the measuring head. The motor-driven positioning device for the measuring head is controllable by a computer connected to the display device. Measurement locations are selectable on the display device and the measuring head is positioned by the positioning device depending on the selected measurement locations.

Positioning device for a color measuring head

A method for controlling color in printing technology machines, includes measuring color measured values without/with a UV filter and converting them with a computer to color measured values measured with/without a UV filter. The color measured values measured without/with a UV filter are recorded by a color measurement instrument on a substrate. The spectral remission values of the substrate measured with and without a UV filter are supplied to the computer and the computer converts color measured values measured without/with a UV filter to color measured values measured with/without a UV filter taking into account these supplied spectral remission values of the substrate, and uses them to control the color in the printing technology machine. A printing technology machine having a computer for carrying out the method, is also provided.

Method and printing technology machine for conversion of color measured values measured without a filter into color measured values measured with a filter and vice versa

A method for color regulation of reproduction copies of a printing press prints a substrate, which appears dark in a standardized color measurement, with at least one printing ink which is lighter than the substrate. At least one color value of the printing ink is determined from a measured variable, and the color value of the at least one printing ink is regulated with the aid of a fixed reference value of a color locus in the color space which is lighter than the printing ink.

Method for color regulation of reproduction copies of a printing press

An apparatus performs colorimetric measurements of printing materials. The apparatus for the colorimetric measurement of printing materials has two measuring devices operating with different resolutions for registering the surface of the printing material. The two measuring devices permit faster registration of color measured values on a printing material and thus accelerates the measuring operations.

Color measuring apparatus having differently operating measuring devices

To perform a method for identifying color measuring strips having measuring areas on printed products, the color measuring strips are scanned with a color measuring instrument. The measured color values acquired by the color measuring instrument are stored in a computer and that the measured color values acquired are each assigned to a printing ink. A sequence formed in this way of printing inks is stored in the computer and then compared with color measuring strip types stored in the computer. The stored color measuring strip type having the greatest probability is then selected.

Method for the identification of color measuring strips

A method for converting polarized color measured values to unpolarized color measured values or vice versa uses a computer. The conversion is carried out by the computer by using a pair of reference measured values determined in polarized and unpolarized form.

Method for converting color measured values in polarized or unpolarized form

A method and a measuring device are proposed for controlling the color application of a printing press () using at least one ink-feeding device () on the basis of spectral reflectance values of printed surface elements () on a print substrate (), which are distinguished in that measured spectral reflectance values are converted into corrected spectral reflectance values. The method and/or the measuring device can be advantageously used in a printing system having a printing press (), to implement a control on the basis of polarized spectral reflectance values, in particular for a detector () which measures unpolarized spectral reflectance values.

Color control for a printing press having spectrally based colorimetry

Spectral, densitometric, or color measured values are detected on sheet printing materials during the printing process in a sheet-fed printing press. The measured values are determined on sheets as they are moving through the printing press and the measured values are used in real-time by a computer to control parameters for controlling the printing process in the sheet-fed printing press.

Inline measurement and closed loop control method in printing machines

A device for inspecting a printed image of a product of a printing press, comprising an image detecting device that furnishes actual image data of the product, and a comparison circuit comparing the actual image data with master image data from a defect-free master image, dividing means for performing a preselectable division of the printed image into inspection areas, and wherein if a defect is detected by the comparison circuit the associated inspection area is designated as being defective.

Device for image inspection

A method for image inspection and color guidance for printing products of a printing press, in which in on-line operation, actual image data of the printed images of the printed products are obtained and compared with nominal image data for the purpose of locating image defects, which comprises the steps of checking, upon the appearance of a defect, before any change in the ink feed is made, as to whether on the basis of the type of defect, some other cause than the color guidance for the deviation is possible.

Method for image inspection and color guidance for printing products of a printing press

A process for controlling coloration in multicolor printing, wherein a photoelectric measuring arrangement (,) is used to obtain actual color measurement values from the printed image (,), wherein the actual color measurement values are compared with specified setpoint color measurement values, and wherein the comparison signals are supplied to a color controlling device (,), with the layer thickness of the ink to be applied to a material to be printed (,) being controllable by means of color controlling elements (,), monitoring signals are continuously derived at selected measuring locations (,), whereby the number of the measuring locations (,) is increased if the monitoring signals exceed a specified threshold value and the actual color measurement values obtained at the increased number (N,) of measuring locations (,) are processed into comparison signal. The invention can be used in multicolor printing machines.

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Wiesloch, Germany

Werner Huber