Method and test pattern for the detection and compensation of missing printing nozzles in an ink jet printing, - printing press

摘要

A method for the detection and compensation of the printing nozzles, which has precipitated out in an ink jet printing, - printing press (7) by means of a computer (6), which the printing of a current print image (8, 15), the receptacle of the printed image (8, 15) by an image sensor (9) and digitization of the print image recorded (8, 15) by the computer (6), the adding of digitized color values of the print image recorded (8) of each column over the entire pressure image height and dividing the summed color values by the number of pixels to obtain a columns profile (10, 10 '), the subtracting an optimized columns profile without precipitated printing nozzles - from the original gap profile (10, 10') to a difference - gap profile (12, 12 '), the setting a threshold for maximum values of the threshold is exceeded, a pressure nozzle which has precipitated out is defined, the use of this threshold for maximum values to the difference - gap profile (12, 12'), as a result of which in the resulting gap profile (13) of each maximum corresponds to a pressure nozzle which has precipitated out is marked, and the compensation of the marked printing nozzles in the subsequent printing process comprises the steps of the method.n="26"