Investigation of CO2 laser beam modulation by rotating polygon

A beam-modulating system based on the rotating polygon has been proposed in a previous experimental work [14]. The aim was to improve the quality and efficiency of CO2 laser surface texturing. Based on the generalized ABCD law, the focusing characteristics of a real beam through the modulating system are investigated in this paper. By introducing a precise defocusing, the velocity synchronization between the focal spot and the workpiece can be realized. Micro-dimples of nearly circular shape can be achieved on the surface. Surface texturing of mill roll has been performed. The experimental and theoretical results are in good agreement.