TY - GEN A1 - Kautek, Wolfgang A1 - Hertwig, Andreas A1 - Martin, Sven A1 - Krüger, Jörg A1 - Lenzner, Matthias A1 - Spielmann, C. A1 - Lenner, M. A1 - Bunte, J. A1 - Puester, T. A1 - Burmester, T. A1 - Fiedler, A. A1 - Heberer, E. A1 - Brose, M. A1 - Stingl, A. A1 - Kiehl, P. A1 - Hönigsmann, H. A1 - Trautinger, F. A1 - Grabner, G. T1 - Safety in Femtosecond Laser Technology - Recent Results of a European Research Project (406) T2 - Conference proceedings & program of the International Laser Safety Conference T2 - International Laser Safety Conference 2003 ; ILSC 2003 CY - Jacksonville, FL, USA DA - 2003-03-10 PY - 2003 SN - 0-912035-38-2 SP - 1(?) EP - 10(?) PB - Laser Institute of America CY - Orlando, Fla. AN - OPUS4-2259 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Hertwig, Andreas A1 - Martin, Sven A1 - Krüger, Jörg A1 - Spielmann, C. A1 - Lenner, M. A1 - Kautek, Wolfgang ED - Dausinger, F. ED - Lichtner, F. ED - Lubatschowski, H. T1 - Primary hazards and reliability of protective materials T2 - Femtosecond technology for technical and medical applications N2 - Femtosecond laser pulses are close to industrial use. The advantages of ultrashort laser pulses for micromachining applications especially in the case of dielectric and biological samples down to pulse durations of 5 fs have been established. The current international standards of laser safety are primarily concerned with CW and pulsed lasers down to the nanosecond range. Therefore, human tissue and laser-protection equipment was investigated with respect to its resistance and protection performance for femtosecond laser illumination down to 30 fs. This included filter glasses for laser protection eyewear, polymer and textile materials used in curtains and guards. Bulk absorber filters can provide enough protection against laser radiation, give a sufficiently broad absorption spectrum. Materials are damaged more easily by femtosecond laser radiation. The need for sufficient spectral broadness as well as the different damage thresholds have to be included in international laser safety standards. This work should trigger the development of novel eye-protection devices that are lighter and ergonomically more acceptable than present commercial models. KW - Lasersicherheit KW - Kurzpulslaser KW - Femtosekunden KW - Lasertechnik KW - Materialbearbeitung PY - 2004 SN - 3-540-20114-9 DO - https://doi.org/10.1007/b96440 SN - 0303-4216 N1 - Serientitel: Topics in applied physics – Series title: Topics in applied physics IS - 96 SP - 287 EP - 307 PB - Springer CY - Berlin AN - OPUS4-4661 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bunte, J. A1 - Barcikowski, S. A1 - Burmester, T. A1 - Püster, T. A1 - Hertwig, Andreas A1 - Kautek, Wolfgang A1 - Krüger, Jörg A1 - Martin, Sven A1 - Spielmann, C. A1 - Lenner, M. A1 - Brose, M. T1 - Sicherer Umgang mit Ultrakurzpuls-Lasern, Teil 2: Sekundäre Gefährdungen JF - Laser-Magazin PY - 2005 SN - 0945-8875 IS - 4 SP - 13 EP - 18 PB - Magazin-Verl. CY - Bad Nenndorf AN - OPUS4-11002 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hertwig, Andreas A1 - Martin, Sven A1 - Krüger, Jörg A1 - Kautek, Wolfgang T1 - Interaction area dependence of the ablation threshold of ion-doped glass JF - Thin solid films N2 - The laser ablation behaviour of ion-doped glass filter materials under irradiation with femtosecond laser pulses was investigated with respect to spot size and repetition rate. The damage threshold fluence of Schott BG18 depends on the size of the irradiated area. The effect is discussed in terms of a defect-site model. KW - Femtosecond KW - Laser KW - Materials processing KW - Ablation KW - Threshold KW - Glass PY - 2004 DO - https://doi.org/10.1016/j.tsf.2003.11.131 SN - 0040-6090 VL - 453-454 SP - 527 EP - 530 PB - Elsevier CY - Amsterdam AN - OPUS4-11046 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hertwig, Andreas A1 - Martin, Sven A1 - Krüger, Jörg A1 - Kautek, Wolfgang T1 - Surface damage and color centers generated by femtosecond pulses in borosilicate glass and silica JF - Applied physics A N2 - Color center generation by femtosecond laser pulses (30 fs) is observed in a fluence range below the damage threshold in an alkali-free barium borosilicate (BBS) glass, and in a thin layer of SiO2 on a fused silica substrate. The color centers are characterized spectroscopically. The optical density of the color centers in BBS glass is by two orders of magnitude higher than that in silica. A healing process with a time constant of about 30 h can be found. PY - 2004 UR - http://www.sciencedirect.com/science/journal/0926860X DO - https://doi.org/10.1007/s00339-004-2634-x SN - 0947-8396 VL - 79 SP - 1075 EP - 1077 PB - Springer CY - Berlin AN - OPUS4-11047 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bunte, J. A1 - Barcikowski, S. A1 - Burmester, T. A1 - Püster, T. A1 - Hertwig, Andreas A1 - Kautek, Wolfgang A1 - Krüger, Jörg A1 - Martin, Sven A1 - Spielmann, C. A1 - Lenner, M. A1 - Brose, M. T1 - Sicherer Umgang mit Ultrakurzpuls-Lasern, Teil 1: Primäre Gefährdungen JF - Laser-Magazin PY - 2005 SN - 0945-8875 IS - 2 SP - 6 EP - 11 PB - Magazin-Verl. CY - Bad Nenndorf AN - OPUS4-11001 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Daminelli-Widany, Grazia A1 - Pentzien, Simone A1 - Hertwig, Andreas A1 - Krüger, Jörg T1 - Influence of film thickness on laser ablation of hydrogenated amorphous carbon films JF - Applied physics N2 - Single-pulse damage thresholds of hydrogenated amorphous carbon (a-C:H) films were measured for 8-ns laser pulses at 532-nm wavelength. Layer thicknesses from below the optical penetration depth to above the thermal diffusion length (60 nm–13 µm) were examined. After correction of the damage-threshold values for the fraction of energy effectively absorbed by the material, the damage threshold was found to increase linearly with the layer thickness, also for film thicknesses below the optical penetration depth of a-C:H. The threshold fluence reached the bulk value for a layer thickness equal to the thermal diffusion length. The thermal diffusion coefficient was obtained from fitting the experimental data. Several phenomena like graphitization, blistering, exfoliation, and ablation were observed for different fluence regimes and film thicknesses. PY - 2006 DO - https://doi.org/10.1007/s00339-005-3460-5 SN - 0340-3793 VL - 83 IS - 1 SP - 89 EP - 94 PB - Springer CY - Berlin AN - OPUS4-12022 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bonse, Jörn A1 - Hertwig, Andreas A1 - Koter, Robert A1 - Weise, Matthias A1 - Beck, Uwe A1 - Reinstädt, Philipp A1 - Griepentrog, Michael A1 - Krüger, Jörg A1 - Picquart, M. A1 - Haro-Poniatowski, E. T1 - Femtosecond laser pulse irradiation effects on thin hydrogenated amorphous carbon layers JF - Applied physics A N2 - The irradiation of ~0.9-µm-thick hydrogenated amorphous carbon (a-C:H) layers deposited on silicon substrates with single femtosecond (fs) laser pulses (35 fs pulse duration, 790 nm centre wavelength) in air is studied experimentally. Irradiation spots have been generated with different peak fluences and subsequently investigated by optical topometry, micro Raman spectroscopy and microscale mechanical indentation in order to evaluate their microscopic, topographical, structural and mechanical properties (e.g. elastic modulus). By this multi-method approach, a clear separation of different effects (delamination and graphitisation) becomes possible. The joint application of mechanical and spectroscopic techniques provides unique insights into the effects of the fs-laser radiation on the carbon layer. PY - 2013 DO - https://doi.org/10.1007/s00339-012-7170-5 SN - 0947-8396 VL - 112 IS - 1 SP - 9 EP - 14 PB - Springer CY - Berlin AN - OPUS4-28629 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Martin, Sven A1 - Hertwig, Andreas A1 - Lenzner, Matthias A1 - Krüger, Jörg A1 - Kautek, Wolfgang T1 - Spot-size dependence of the ablation threshold in dielectrics for femtosecond laser pulses JF - Applied physics A N2 - The multi-pulse ablation threshold of barium borosilicate glass was measured using 30-fs pulses of a high repetition rate (1 kHz) laser system. The threshold fluence was found to decrease with increasing beam radius ranging from 20 to 400 m. Two existing models are applied by considering thermal accumulation and point defects, respectively . PY - 2003 DO - https://doi.org/10.1007/s00339-003-2213-6 SN - 0947-8396 VL - 77 IS - 7 SP - 883 EP - 884 PB - Springer CY - Berlin AN - OPUS4-6317 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hertwig, Andreas A1 - Martin, S. A1 - Kautek, Wolfgang A1 - Krüger, Jörg ED - Maruray, L. T1 - Ultra-short Pulse Laser Safety - a Challenge to Materials Science T2 - Optical design and engineering II N2 - In this paper, safety-related experiments with ultra-short laser pulses (down to 30 fs) on various components (goggles, curtains) for laser protection are presented. The damage and failure behaviour of protective devices has been investigated dependent on practical conditions such as pulse duration, laser .uence, pulse number, and repetition rate. The e.ects of laser-irradiation on materials can be roughly divided into transient ones like laserinduced transmission (LIT) or short-lived colour centres and permanent damages like the stable colour centres and ablation. The former e.ects are particularly important for transparent devices like laser goggles. To obtain a complete overview on laser safety issues and the prevention of failure there are two important .elds of investigation: 1. the e.ects of laser radiation on human eyes and skin, and 2. on the possible protection materials. Both .elds have been addressed during the recently .nished German project SAFEST (safety aspects in femtosecond technology). The amount of safety data available in the ultrashort pulse region has been increased remarkably. This allows for a re-evaluation of known laser protection materials for this region of pulse durations and for the evaluation of new designs that promise high protection levels while being light-weight and convenient to use. T2 - Optical design and engineering II CY - Jena, Germany DA - 2005-09-13 PY - 2005 N1 - Serientitel: Proceedings of SPIE – Series title: Proceedings of SPIE IS - 5962 SP - 59622J-1 - 59622J-10 PB - SPIE CY - Bellingham AN - OPUS4-11593 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -