Abstract
In this paper, a technique of speckle measurement has been developed for evaluating the wetting state on a surface of offset printing plate. The present method can provide not the amount of water supplied to a printing plate, but the information of the wetting state on the plate to automate the system for water supplying in offset printing machine. The experimental results demonstrate that the speckle intensity increases for the wetting state suitable for better offset printing as compared with that for short or excessive water supplying.
