A N_2 Plasma Light Source Generated in Hollow Cathode Discharge and its Application in Lithographic Plate Making

摘要

Computer to conventional plate (CTCP) technology is getting more and more attention in printing industries. In this paper we report a nitrogen plasma light source generated in hollow cathode discharge (HCD), which is used for pre-sensitivity (PS) plate exposure. The N_2 molecule emits abundant spectrum ranging from 350-460nm. With the voltage 580V, current 1.8Aand pressure 70Pa an optical power density of 0.46mW/cm~2 is obtained. The optical density could be further increased with optimizing the lens system. The phototonus efficiency of this source is discussed in detail from the chemical principle and the FTIR analysis on the coating material.