Abstract
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Laser engraving requires a precise ablation per pulse through all layers of a depth map. To transform this
process towards areas of a square meter and more within an acceptable time, needs high-power ultra-short
pulsed lasers for the precision and a high scan speed for the beam distribution. Scan speeds in the range of
several 100 m/s can be achieved with a polygon scanner. In this work, a polygon scanner has been utilized
within a roll-engraving machine to treat an 800 x 220 mm² (L x Dia) roll with 0.55 m² in a laser engraving
process. The machine setup, the processing strategy and the data handling has been investigated and result in an efficient large area process. Pre-tests were performed with a multi-MHz-frequency nanosecond-pulsed laser, to investigate the processing strategy. A method to overcome the duty cycle of the polygon scanner was found in the synchronization of two polygons, enabling the use on a single laser source in a time-sharing concept. The throughput and the utilization of the laser source can be increased by the factor of two