@inproceedings{SchwarzEsenHellmann2018, author = {Schwarz, Simon and Esen, Cemal and Hellmann, Ralf}, title = {Homogeneous low spatial frequency LIPSS on dielectrics generated by beam-shaped femtosecond pulsed laser irradiation}, series = {LPM2018 The 19th International Symposium on Laser Precision Microfabrication}, booktitle = {LPM2018 The 19th International Symposium on Laser Precision Microfabrication}, year = {2018}, subject = {Femtosekundenlaser}, 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{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{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{KeferRosenbergerHessleretal.2020, author = {Kefer, Stefan and Rosenberger, Manuel and Hessler, Steffen and Girschikofsky, Maiko and Belle, Stefan and Roth, Gian-Luca and Schmauß, Bernhard and Hellmann, Ralf}, title = {Fabrication and Applications of Polymer Planar Bragg Grating Sensors based on Cyclic Olefin Copolymers}, series = {2019 Photonics \& Electromagnetics Research Symposium - Fall (PIERS - Fall)}, booktitle = {2019 Photonics \& Electromagnetics Research Symposium - Fall (PIERS - Fall)}, publisher = {Institute of Electrical and Electronics Engineers}, isbn = {978-1-7281-5304-9}, doi = {10.1109/PIERS-Fall48861.2019.9021801}, pages = {647 -- 655}, year = {2020}, abstract = {This contribution reviews recent advancements, current research and possible applications of polymer planar Bragg grating (PPBG) sensors with a focus on the utilization of cyclic olefin copolymer (COC) substrates. COC-PPBGs can be handled and fabricated efficiently by employing a single writing step procedure which features simultaneous generation of waveguide and Bragg grating structure within an injection molded substrate. The resulting photonic structures exhibit an attenuation as low as 1.2 dB cm-1 and a reflectivity up to 99 \%. The potential of COC-PPBGs for high-temperature applications is proven by demonstrating temperature measurements up to 160 °C. Moreover, it is possible to employ single PPBGs for multidimensional stress and strain sensing or even three-dimensional shape reconstruction. Due to their excellent properties, it is feasible to integrate COC-PPBGs into commercial-grade carbon fiber reinforced polymer workpieces for structural health monitoring. Furthermore, utilization of appropriate coatings enables functionalization of PPBGs for refractive index sensing and thus biochemical applications. Beside the fabrication and characterization of COC-based PPBGs, this contribution exemplifies and reviews such applications.}, subject = {Optischer Sensor}, language = {en} } @inproceedings{RischHuehnleinKnoelletal.2009, author = {Risch, Anna and H{\"u}hnlein, Kristof and Kn{\"o}ll, J{\"u}rgen and Hellmann, Ralf}, title = {Laserscribing of transparent conductive oxides - a comparative study using nanosecond and picosecond pulsed solid state lasers}, series = {Proceedings of the 20st International Scientific Conference, Mittweida, 2009}, booktitle = {Proceedings of the 20st International Scientific Conference, Mittweida, 2009}, year = {2009}, subject = {Festk{\"o}rperlaser}, language = {en} } @inproceedings{KaloumenosAmrheinGlaabetal.2010, author = {Kaloumenos, Mareiki and Amrhein, Frank and Glaab, Johannes and Sauer, Michael and Hellmann, Ralf and Kaloudis, Michael}, title = {Development of a UV-Light Source with Highest Power Density Based on Light Emitting Diode Technology for Applications in Production Engineering, in Production Engineering and manufacturing Systems}, series = {Proceedings of the XXIV International Scientific Conference Miskolc, Ungarn}, booktitle = {Proceedings of the XXIV International Scientific Conference Miskolc, Ungarn}, year = {2010}, subject = {Lumineszenzdiode}, language = {en} } @inproceedings{HuehnleinTschirpkeHellmann2010, author = {H{\"u}hnlein, Kristof and Tschirpke, Katrin and Hellmann, Ralf}, title = {Optimisation of laser cutting using design of experiment - A comparative study of cutting thin ceramic layers using a fibre laser and a CO2 laser}, series = {Physics procedia}, volume = {5}, booktitle = {Physics procedia}, number = {Part B}, issn = {1875-3892}, pages = {243 -- 252}, year = {2010}, subject = {Laserschneiden}, language = {en} } @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{ScheurichBelleHellmannetal.2009, author = {Scheurich, Steffen and Belle, Stefan and Hellmann, Ralf and So, Sik and Sparrow, Ian and Emmerson, Greg}, title = {Planar optical waveguide bragg grating chemical sensor for online process control}, series = {3rd integrated optics - sensors, sensing structures and methodes Korbielow, PL}, booktitle = {3rd integrated optics - sensors, sensing structures and methodes Korbielow, PL}, year = {2009}, subject = {Bragg-Reflektor}, language = {en} }