@inproceedings{RosenbergerBelleHellmann2011, author = {Rosenberger, Manuel and Belle, Stefan and Hellmann, Ralf}, title = {Detection of biochemical reaction and DNA hybridization using a planar bragg grating sensor}, series = {Proceeding SPIE, Vol. 8073, article id: 80730C}, booktitle = {Proceeding SPIE, Vol. 8073, article id: 80730C}, number = {8073}, doi = {10.1117/12.886785}, year = {2011}, subject = {Bragg-Reflektor}, language = {en} } @inproceedings{SchwarzRungEsenetal.2020, author = {Schwarz, Simon and Rung, Stefan and Esen, Cemal and Hellmann, Ralf}, title = {Current results on laser-based production of complex optics in glass}, series = {10. Wetzlarer Herbsttagung "Moderne Optikfertigung", 29. - 30. September 2020, Wetzlar}, booktitle = {10. Wetzlarer Herbsttagung "Moderne Optikfertigung", 29. - 30. September 2020, Wetzlar}, year = {2020}, subject = {Laserbearbeitung}, language = {en} } @inproceedings{AdelmannHellmann2015, author = {Adelmann, Benedikt and Hellmann, Ralf}, title = {Comparative study of experimentally determined and simulated mechanical strength of fiber laser cut alumina substrates}, series = {Proceedings of the 7th International Congress on Laser Advanced Materials Processing}, volume = {2015}, booktitle = {Proceedings of the 7th International Congress on Laser Advanced Materials Processing}, number = {15}, pages = {1 -- 9}, year = {2015}, subject = {Laserschneiden}, language = {en} } @inproceedings{SchwarzEsenHellmann2018, author = {Schwarz, Simon and Esen, Cemal and Hellmann, Ralf}, title = {CO2 laser polishing of femtosecond shaped micro-optical components}, series = {3rd Conference on Laser Polishing LaP 2018}, booktitle = {3rd Conference on Laser Polishing LaP 2018}, year = {2018}, subject = {Kohlendioxidlaser}, language = {en} } @inproceedings{DudutisPipirasSchwarzetal.2019, author = {Dudutis, Juozas and Pipiras, Jokūbas and Schwarz, Simon and Rung, Stefan and Hellmann, Ralf and Gečys, Paulius}, title = {Bessel beam formation with all laser fabricated axicon - case of glass dicing applications}, series = {COLA 2019, 15th International Conference on Laser Ablation}, booktitle = {COLA 2019, 15th International Conference on Laser Ablation}, year = {2019}, subject = {Laserbestrahlung}, language = {en} } @inproceedings{RungRexhepiHellmann2013, author = {Rung, Stefan and Rexhepi, Mal and Hellmann, Ralf}, title = {Beam shaping for enhanced through-put of laser ablation of transparent conductive films}, series = {Proceedings of the XXVII MicroCAD International Scientific Conference}, volume = {2013}, booktitle = {Proceedings of the XXVII MicroCAD International Scientific Conference}, year = {2013}, subject = {Laserablation}, language = {en} } @inproceedings{SchwarzRungEsenetal.2018, author = {Schwarz, Simon and Rung, Stefan and Esen, Cemal and Hellmann, Ralf}, title = {Axicon fabrication with ultrashort and CO2 laser}, series = {LPM2018 The 19th International Symposium on Laser Precision Microfabrication}, booktitle = {LPM2018 The 19th International Symposium on Laser Precision Microfabrication}, year = {2018}, subject = {Ultrakurzzeitlaser}, language = {de} } @inproceedings{ScheurichBelleHellmannetal.2009, author = {Scheurich, Steffen and Belle, Stefan and Hellmann, Ralf and So, Sik and Sparrow, Ian and Emmerson, Greg}, title = {Application of a silica-on-silicon planar optical waveguide. Bragg grating sensor for organic liquid compound detection}, series = {SPIE Optics an optoelectronics conference, Proceedings of SPIE, Vol. 7356, Prag, CR}, booktitle = {SPIE Optics an optoelectronics conference, Proceedings of SPIE, Vol. 7356, Prag, CR}, number = {7356}, isbn = {978-0819476302}, year = {2009}, subject = {Bragg-Reflektor}, language = {en} } @inproceedings{SchwarzRungEsenetal.2020, author = {Schwarz, Simon and Rung, Stefan and Esen, Cemal and Hellmann, Ralf}, title = {All laser-based fabrication of optical elements}, series = {Proceedings of SPIE 11270, Frontiers in Ultrafast Optics: Biomedical, Scientific, and Industrial Applications XX}, booktitle = {Proceedings of SPIE 11270, Frontiers in Ultrafast Optics: Biomedical, Scientific, and Industrial Applications XX}, year = {2020}, subject = {Ultrakurzzeitlaser}, language = {de} } @inproceedings{BischoffEsenHellmann2023, author = {Bischoff, Kay and Esen, Cemal and Hellmann, Ralf}, title = {Acceleration of Femtosecond Reductive Laser Sintering of Copper(II) Oxide for Conductive Copper Patterns on Cyclic Olefin Copolymers}, series = {International Congress on Applications of Lasers \& Electro-Optics (ICALEO) 2023}, booktitle = {International Congress on Applications of Lasers \& Electro-Optics (ICALEO) 2023}, year = {2023}, abstract = {We report on the acceleration of femtosecond reductive laser sintering of copper (II) oxide on the surface of transparent cyclic olefin copolymers (COC) by varying the focus size to generate metallic copper (Cu) layers. By using different focusing conditions, different process speeds are achieved, and the structural accuracies are controlled. The formation of Cu lines is observed for different focus sizes at various scan speeds, which is attributed to laser exposure duration and chemical reaction time. The formed lines are categorized and measured by optical microscopy and provide the basis for two-dimensional Cu surfaces. By hatching, high quality conductive films are produced with an increased focus diameter of up to 400 µm at a scan speed of 400 mm/s and a hatch distance of 250 µm resulting in a multiple increased process speed by a factor of thirteen compared to previous research. Using 4-tip measurement , a low sheet resistance of 0.165 Ω/sq was validated on these Cu films, which have an atomic Cu content of 89.5\%.}, subject = {Femtosekundenlaser}, language = {en} }