Schlutow Henrike, Fuchs Ulrike, Müller Frank A, Gräf Stephan
Asphericon GmbH, Stockholmer Str. 9, 07747 Jena, Germany.
Otto Schott Institute of Materials Research (OSIM), Friedrich Schiller University, Löbdergraben 32, 07743 Jena, Germany.
Materials (Basel). 2021 Aug 31;14(17):4981. doi: 10.3390/ma14174981.
Tailored intensity profiles within the focal spot of the laser beam offer great potential for a well-defined control of the interaction process between laser radiation and material, and thus for improving the processing results. The present paper discusses a novel refractive beam-shaping element that provides different squared intensity distributions converted from the Gaussian output beam of the utilized femtosecond (fs) laser. Using the examples of surface structuring of stainless-steel on the micro- and nano-scale, the suitability of the beam-shaping element for fs-laser material processing with a conventional f-Theta lens is demonstrated. In this context, it was shown that the experimental structuring results are in good agreement with beam profile measurements and numerical simulations of the beam-shaping unit. In addition, the experimental results reveal the improvement of laser processing in terms of a significantly reduced processing time during surface nano-structuring and the possibility to control the ablation geometry during the fabrication of micro-channels.
激光束焦斑内的定制强度分布为精确控制激光辐射与材料之间的相互作用过程提供了巨大潜力，从而有助于改善加工结果。本文讨论了一种新型折射光束整形元件，它能将所使用的飞秒（fs）激光的高斯输出光束转换为不同的平方强度分布。以不锈钢在微米和纳米尺度上的表面结构化为例，展示了该光束整形元件在使用传统f-θ透镜进行飞秒激光材料加工中的适用性。在此背景下，实验结构化结果与光束整形单元的光束轮廓测量和数值模拟结果吻合良好。此外，实验结果表明，在表面纳米结构化过程中，激光加工时间显著缩短，且在微通道制造过程中能够控制烧蚀几何形状，从而改进了激光加工。
