Additive plate making system and method

A system for constructing a printing plate comprising a plurality of layers of a photopolymer deposited on a substrate by additive manufacturing, the system comprising:

• a printing assembly comprising:
• one or more ink jet print heads each comprising a plurality of nozzles configured to deposit a layer of the photopolymer on the substrate, the photopolymer curable by radiation in a predetermined wavelength range;
• at least one wide area radiation source configured to emit radiation in the predetermined wavelength range and having a first addressable area of coverage,
• a small area radiation source configured to emit radiation in the predetermined wavelength range with a modulation in accordance with a desired image to be printed by the printing plate and at a resolution corresponding to the desired image to be printed by the printing plate, the small area radiation source having one or more second discrete addressable areas of coverage, each second discrete addressable area of coverage smaller than the first addressable area of coverage;
• means for providing relative motion between the substrate and the printing assembly;
• a controller configured for controlling the relative motion between the substrate and the printing assembly in accordance with instructions stored in a digital memory;
• wherein the one or more ink jet print heads comprises a plurality of n ink jet print heads, and the at least one wide area radiation source includes a single wide area radiation source configured to cure, and the controller in accordance with the instructions is configured to cause the single wide area radiation source to cure, each layer deposited by a first through (n-m)th inkjet layers before deposition of subsequent layers (n-m+1) to n, and the small area radiation source is positioned to cure, and the controller in accordance with the instructions is configured to cause the small area radiation source to cure, the (n-m+1)th to nth layers after deposition.