Apparatus and method for multi-beam direct engraving of elastomeric printing plates and sleeves

A method of laser engraving a printing plate or a printing sleeve, the method comprising:

• emitting from a laser source an incident laser beam with sufficient power output to directly engrave an elastomeric printing plate or sleeve positioned on an imaging drum of a drum imager or on a flat bed of a flatbed imager, the drum or sleeve of the drum imager being rotatable around a longitudinal axis, and having a longitudinal direction defined by the axis of rotation and a transverse direction defined along the circumference of the drum, the flatbed imager having a longitudinal direction and a transverse direction perpendicular to the longitudinal direction, the plate or sleeve having an outer surface and an elastomeric body;
• splitting the laser beam by one or more beam splitters to create a plurality of split beams;
• simultaneously modulating the plurality of split beams using a plurality of optical-beam modulators to create one or more modulated beams from each split beam, each respective optical-beam modulator controlled according to a respective portion of imaging data;
• and
• simultaneously focusing the one or more modulated beam to create one or more focused modulated beams, the focused modulated beams focused at a plurality of depths from the outer surface of the printing plate or sleeve,
• wherein each focused modulated beam has a focal spot with a focal size, and at least two respective focal spots of two respective focused modulated beams are at different locations on the outer surface of the printing plate or sleeve and are focused at different respective depth levels in the body of the printing plate or sleeve, such that the outer surface of the printing plate or sleeve is simultaneously engraved by the plurality of modulated beams of different respective focal spot sizes on the outer surface;
• and
• wherein the focused modulated beams build a row along the axial direction of the printing plate or sleeve.