TY - JOUR A1 - Schwarz, Simon A1 - Hellmann, Ralf T1 - Fabrication of Cylindrical Lenses by Combining Ultrashort Pulsed Laser and CO2 Laser JF - Journal of Laser Micro/Nanoengineering KW - Zylinderlinse Y1 - 2017 VL - 12 IS - 2 SP - 76 EP - 79 ER - TY - JOUR A1 - Schwarz, Simon A1 - Rung, Stefan A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Influence of pulse duration on high-precision manufacturing of 3D geometries JF - Journal of Laser Micro/Nanoengineering KW - Dreidimensionale Geometrie Y1 - 2018 VL - 13 IS - 3 SP - 292 EP - 295 ER - TY - JOUR A1 - Schwarz, Simon A1 - Rung, Stefan A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Homogeneous low spatial frequency LIPSS on dielectric materials generated by beam-shaped femtosecond pulsed laser irradiation JF - Journal of Laser Micro/Nanoengineering KW - Femtosekundenlaser Y1 - 2018 VL - 13 IS - 2 SP - 90 EP - 94 ER - TY - JOUR A1 - Schwarz, Simon A1 - Rung, Stefan A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Rapid fabrication of precise glass axicon arrays by an all laser-based manufacturing technology JF - Journal of Laser Applications KW - Femtosekundenlaser Y1 - 2020 VL - 32 IS - 1 SP - 012001 EP - 012001 ER - TY - JOUR A1 - Schwarz, Simon A1 - Rung, Stefan A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Surface Plasmon Polariton Triggered Generation of 1D-Low Spatial Frequency LIPSS on Fused Silica JF - Applied Sciences KW - Femtosekundenlaser KW - Quarzglas Y1 - 2018 VL - 8 IS - 9 SP - 1624 EP - 1624 ER - TY - JOUR A1 - Rung, Stefan A1 - Bokan, Kevin A1 - Schwarz, Simon A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Influence of laser wavelength on the modification of friction between 100Cr6 steel and polytetrafluoroethylene by femtosecond laser-induced periodic surface structures JF - Journal of Laser Applications KW - Femtosekundenlaser Y1 - 2020 U6 - https://doi.org/10.2351/7.0000036 VL - 32 IS - 3 SP - 032017-1 EP - 032017-6 ER - TY - JOUR A1 - Schwarz, Simon A1 - Roth, Gian-Luca A1 - Rung, Stefan A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Fabrication and evaluation of negative axicons for ultrashort pulsed laser applications JF - Optics Express KW - Ultrakurzzeitlaser Y1 - 2020 VL - Optics Express IS - 28 SP - 26207 EP - 26217 ER - TY - CHAP A1 - Schwarz, Simon A1 - Rung, Stefan A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Manufacturing of optical elements by non-contact laser processing T2 - Seventh European Seminar on Precision Optics Manufacturing, Proceedings KW - Laserbearbeitung KW - Optisches Bauelement Y1 - 2020 IS - 11478 ER - TY - JOUR A1 - Dudutis, Juozas A1 - Pipiras, Jokūbas A1 - Schwarz, Simon A1 - Rung, Stefan A1 - Hellmann, Ralf A1 - Račiukaitis, Gediminas A1 - Gečys, Paulius T1 - Laser-fabricated axicons challenging the conventional optics in glass processing applications JF - Optics Express KW - Laserbearbeitung KW - Quarzglas Y1 - 2020 VL - 28 IS - 4 SP - 5715 EP - 5730 ER - TY - JOUR A1 - Schwarz, Simon A1 - Rung, Stefan A1 - Hellmann, Ralf T1 - Two-Dimensional Low Spatial Frequency Laser-Induced Periodic Surface Structuring of Sapphire JF - Journal of Laser Micro/Nanoengineering KW - Femtosekundenlaser Y1 - 2017 VL - 12 IS - 2 SP - 67 EP - 71 ER - TY - CHAP A1 - Schwarz, Simon A1 - Rung, Stefan A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - All laser-based fabrication of optical elements T2 - Proceedings of SPIE 11270, Frontiers in Ultrafast Optics: Biomedical, Scientific, and Industrial Applications XX KW - Ultrakurzzeitlaser KW - Kohlendioxidlaser KW - Femtosekundenlaser Y1 - 2020 ER - TY - CHAP A1 - Schwarz, Simon A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - CO2 laser polishing of femtosecond shaped micro-optical components T2 - 3rd Conference on Laser Polishing LaP 2018 KW - Kohlendioxidlaser Y1 - 2018 ER - TY - CHAP A1 - Schwarz, Simon A1 - Rung, Stefan A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Axicon fabrication with ultrashort and CO2 laser T2 - LPM2018 The 19th International Symposium on Laser Precision Microfabrication KW - Ultrakurzzeitlaser KW - Kohlendioxidlaser Y1 - 2018 ER - TY - CHAP A1 - Schwarz, Simon A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Homogeneous low spatial frequency LIPSS on dielectrics generated by beam-shaped femtosecond pulsed laser irradiation T2 - LPM2018 The 19th International Symposium on Laser Precision Microfabrication KW - Femtosekundenlaser Y1 - 2018 ER - TY - CHAP A1 - Schwarz, Simon A1 - Rung, Stefan A1 - Hellmann, Ralf T1 - High quality one-dimensional low spatial frequency LIPSS on sapphire generated by Top-Hat beam shaped ultrashort-pulsed laser T2 - MultiScience - XXXI. microCAD International Multidisciplinary Scientific Conference KW - Ultrakurzzeitlaser Y1 - 2017 ER - TY - CHAP A1 - Schwarz, Simon A1 - Rung, Stefan A1 - Hellmann, Ralf T1 - Simulation of process parameters towards the generation of low spatial frequency LIPSS on dielectric materials T2 - MultiScience - XXX. microCAD International Multidisciplinary Scientific Conference KW - Laserbestrahlung KW - Quarzglas Y1 - 2016 ER - TY - CHAP A1 - Dudutis, Juozas A1 - Pipiras, Jokūbas A1 - Schwarz, Simon A1 - Rung, Stefan A1 - Hellmann, Ralf A1 - Gečys, Paulius T1 - Bessel beam formation with all laser fabricated axicon - case of glass dicing applications T2 - COLA 2019, 15th International Conference on Laser Ablation KW - Laserbestrahlung Y1 - 2019 ER - TY - CHAP A1 - Dudutis, Juozas A1 - Pipiras, Jokūbas A1 - Schwarz, Simon A1 - Rung, Stefan A1 - Hellmann, Ralf A1 - Račiukaitis, Gediminas A1 - Gečys, Paulius T1 - Glass cutting by oblate-tip axicon-generated Bessel-Gaussian beams T2 - Open Readings, 63rd International Conference for Students of Physics and Natural Sciences KW - Laserschneiden KW - Glas Y1 - 2019 ER - TY - JOUR A1 - Gvozdovskyy, Igor A1 - Bratova, Daria A1 - Kazantseva, Z. A1 - Malyuta, S. A1 - Lytvyn, Petro A1 - Schwarz, Simon A1 - Hellmann, Ralf T1 - Light-controllable hybrid aligning layer based on LIPSS on sapphire surface and PVCN-F film JF - Journal of Molecular Liquids N2 - The creation of aligning layers for the uniform orientation of liquid crystals is significant for both research and the application of liquid crystals. For all applications, the creation of aligning layers possessing controllable characteristics such as azimuthal and polar anchoring energies, easy-axis of director alignment and pretilt angle, in the same way as it is achieved by using photoaligning layers processed by light, is very important. Here, aligning properties of hybrid aligning layers created on the basis of sapphire surfaces additionally coated by photoaligning layer of PVCN-F are studied. These hybrid layers possess the properties of the nano-structured sapphire layer and the photosensitive PVCN-F layer, and complement each other. The irradiation time dependence of the azimuthal anchoring energy of the hybrid layers is studied. By using certain experimental conditions during irradiation of hybrid layers, e.g., polarization of light and irradiation time, a minimum value of the azimuthal anchoring energy, close to zero, was obtained. Atomic force microscope studies of the irradiated hybrid layers were also carried out. It was found that the behavior of the contact angle of nematic droplets placed on treated sapphire surfaces are in good agreement with properties of hybrid aligning layers and parameters of structuring surface obtained from AFM images. KW - Flüssigkristall KW - Saphir KW - Kristallfläche Y1 - 2023 U6 - https://doi.org/10.1016/j.molliq.2023.122623 VL - 387 IS - keine SP - 122623 EP - 122623 ER - TY - CHAP A1 - Lutz, Christian A1 - Schwarz, Simon A1 - Rung, Stefan A1 - Marx, Jan A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Optical system for multi Bessel beam high power ultrashort pulsed laser processing using a spatial light modulator T2 - Lasers in Manufacturing - LiM 2021 N2 - We report on an optical setup for multi Bessel beam processing combining a refractive axicon and a spatial light modulator. Based on their particular beam profile, Bessel beams exhibit various advantages over conventional Gaussian beams for ultrashort pulsed laser processing. Especially for micromachining of transparent materials, applications such as micro-hole drilling or the generation of voids benefit from the increased focal length of the applied Bessel beam. In addition, on account of the significantly increased average output power of industrial ultrashort pulsed lasers over the last years, there is a high demand on multi spot applications for using the available laser power in efficient production processes. Our optical concept combines the dynamic possibilities of beam splitting using spatial light modulator with the benefits of Bessel beams facilitating multi Bessel beam processing. KW - Ultrakurzzeitlaser KW - Lichtmodulator Y1 - 2021 ER - TY - JOUR A1 - Lutz, Christian A1 - Schwarz, Simon A1 - Marx, Jan A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Multi-Bessel Beams Generated by an Axicon and a Spatial Light Modulator for Drilling Applications JF - MDPI Photonics N2 - We report on an optical setup to generate multi-Bessel beam profiles combining a refractive axicon and a spatial light modulator. Based on their particular beam profile, Bessel beams offer advantageous properties for micro drilling processes and internal volume processing, especially for transparent materials. In addition, the laser power of industrial, ultrashort pulsed lasers has increased significantly over the last few years, offering the possibility for highly efficient processes using multi-spot profiles. Our optical concept combines the dynamic possibilities of beam splitting using a spatial light modulator with the benefits of Bessel beams, which facilitates multi-Bessel beam processing. Beside the simulation and experimental evaluation of the generated multi-Bessel beams, we exemplify the applicability of the developed module for the perforation of thin metal foils by micro drilling. KW - Bessel beam KW - Axicon KW - Optical System KW - Ultrashort pulsed laser KW - Material ablation KW - Bessel-Bündel KW - Ultrakurzzeitlaser Y1 - 2023 UR - https://www.mdpi.com/2304-6732/10/4/413 U6 - https://doi.org/10.3390/photonics10040413 VL - 2023 IS - 10/413 SP - 1 EP - 9 ER - TY - CHAP A1 - Lutz, Christian A1 - Schwarz, Simon A1 - Marx, Jan A1 - Esen, Cemal A1 - Hellmann, Ralf ED - Kling, Rainer ED - Pfleging, Wilhelm ED - Sugioka, Koji T1 - Combination of an axicon and a spatial light modulator for the generation of multiBessel beams for microdrilling using ultrashort pulsed laser T2 - Laser-based Micro- and Nanoprocessing XVIII N2 - Due to their special beam profile, Bessel beams offer advantageous properties for micro-drilling and internal volume processing, especially for transparent materials. In addition, the laser power of industrial ultrashort pulsed lasers hasnincreased significantly in recent years, offering the possibility of highly efficient processes using multi-spot profiles. We report on optical simulations and an experimental optical setup for generating multi-Bessel beams by combining a refractive axicon and a spatial light modulator. This setup offers a new possibility of multi-Bessel beam generation by functional division of the Bessel beam generation by the axicon and the possibility of separation flexible beam splitting by a spatial light modulator. The beam profiles generated with this setup are analyzed and compared in this study using optical simulations and experiments. In addition to the analysis of the Bessel beams in the machining plane, they are also analyzed in the propagation direction by means of intensity distributions measured by a camera in small-step z positions. Furthermore, the experimental applicability of the module-based beam shaping system is demonstrated by integrating into an existing laser system. KW - Ultrakurzzeitlaser Y1 - 2024 U6 - https://doi.org/10.1117/12.3000946 PB - SPIE ER - TY - JOUR A1 - Franz, Daniel A1 - Schuster, David A1 - Schwarz, Simon A1 - Rung, Stefan A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Fabrication and analysis of through-glass vias for glass-based electronic packaging using an ultrashort pulsed laser JF - Optics and Lasers in Engineering KW - Ultrakurzzeitlaser KW - Laserbohren Y1 - 2025 U6 - https://doi.org/10.1016/j.optlaseng.2025.109106 SN - 0143-8166 VL - 193 PB - Elsevier BV ER - TY - CHAP A1 - Franz, Daniel A1 - Schuster, David A1 - Schwarz, Simon A1 - Rung, Stefan A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Ultrashort pulsed laser drilling of through-glass vias for glass core packaging T2 - Proceedings of LAMP2025 – the 9th International Congress on Laser Advanced Materials Processing, Ise-City, Japan, June 2025 KW - Ultrakurzzeitlaser KW - Laserbohren Y1 - 2025 ER -