Color control for a printing press having spectrally based colorimetry
AssigneeHeidelberger Druckmaschinen AG
InventorsHans Engler, Werner Huber, Manfred Schneider
Life of this patent
Estimating the term…
Abstract
A method and a measuring device are proposed for controlling the color application of a printing press (10) using at least one ink-feeding device (20) on the basis of spectral reflectance values of printed surface elements (24) on a print substrate (22), 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 (10), to implement a control on the basis of polarized spectral reflectance values, in particular for a detector (28) which measures unpolarized spectral reflectance values.
Claims18
A method for controlling color in a printing press using at least one ink-feeding device, comprising the steps of:
- determining spectral reflectance values by taking measurements on at least one printed surface element on a print substrate;
- converting the spectral reflectance values into corrected spectral reflectance values;
- determining actual values for ink-feeding variables as a function of the corrected spectral reflectance values;
- and
- providing control data for the ink-feeding device as a function of the actual values obtained for the ink-feeding variables and setpoint values for the ink-feeding variables.
A measuring device comprising:
- a detector for measuring spectral reflectance values on at least one printed surface element on a print substrate;
- and
- a control unit including a processor unit and a memory unit, the control unit including program executable steps at least partially stored for a time period in the memory unit and executable by the processor unit, the program executable steps including computing corrected spectral reflectance values as a function of the spectral reflectance values.
A printing system comprising:
- at least one printing press including at least one print unit, an ink-feeding device, and a machine-control unit, and
- at least one measuring device, the measuring device including a detector for measuring spectral reflectance values on at least one printed surface element on a print substrate;
- and a control unit including a processor unit and a memory unit, the control unit including program executable steps at least partially stored for a time period in the memory unit and executable by the processor unit, the program executable steps including computing corrected spectral reflectance values as a function of the spectral reflectance values.
Dependencies are inferred from the claim text.