Exposure method and apparatus for imaging a printing plate for wet offset printing

摘要

A laser (23) generates strip shaped laser spots (28) on the printing plate (12). Each has a spot width (Bs) measured in the direction of the relative movement between form and laser array much smaller than that of an image pixel measured in the same direction and than that of the laser spot length (Ls). The pulse duration of each spot is much longer than the time taken to traverse a distance equal to the spot length in the direction of the relative movement.