Method and apparatus for register correction

摘要

A method and apparatus for measuring and correcting register errors in multi-color printing machines is disclosed. A multi-color sheet that has been printed having register marks for each color is placed on a measuring table. The approximate locations of the register pairs and the accurate spacings of the individual register marks in each pair are determined by a light stylus, an electronic color video measuring camera system or on a measuring table having a digitizer surface. The values are entered into a computer which calculates the corrective values to be used to relocate one or more of the printing plates carried by each plate cylinder to achieve color registry in multi-color printing.