PRINTING

摘要

A method of printing on both sides of a substrate (20) comprising checking the relative positions of images on the front and back of the printed substrate (20) by capturing an image (100, 100) of markings (60, 62, 50, 52) on the front and back by imaging the printed substrate (20) from one side only, the markings on the back (60, 62) being seen through the material of the substrate (20).