Browsing by Author "Thiele, Simon"

Now showing 1 - 11 of 11

Open Access
3D direct laser writing of highly absorptive photoresist for miniature optical apertures
(2022) Schmid, Michael D.; Toulouse, Andrea; Thiele, Simon; Mangold, Simon; Herkommer, Alois; Giessen, Harald
The importance of 3D direct laser writing as an enabling technology increased rapidly in recent years. Complex micro-optics and optical devices with various functionalities are now feasible. Different possibilities to increase the optical performance are demonstrated, for example, multi-lens objectives, a combination of different photoresists, or diffractive optical elements. It is still challenging to create fitting apertures for these micro optics. In this work, a novel and simple way to create 3D-printed opaque structures with a highly absorptive photoresist is introduced, which can be used to fabricate microscopic apertures increasing the contrast of 3D-printed micro optics and enabling new optical designs. Both hybrid printing by combining clear and opaque resists, as well as printing transparent optical elements and their surrounding opaque apertures solely from a single black resist by using different printing thicknesses are demonstrated.
Open Access
3D printed micro-optics for quantum technology: Optimised coupling of single quantum dot emission into a single-mode fibre
(2021) Sartison, Marc; Weber, Ksenia; Thiele, Simon; Bremer, Lucas; Fischbach, Sarah; Herzog, Thomas; Kolatschek, Sascha; Jetter, Michael; Reitzenstein, Stephan; Herkommer, Alois; Michler, Peter; Portalupi, Simone Luca; Giessen, Harald
Open Access
3D printed stacked diffractive microlenses
(2019) Thiele, Simon; Pruss, Christof; Herkommer, Alois; Giessen, Harald
Open Access
3D-printed miniature spectrometer for the visible range with a 100 × 100 μm2 footprint
(2021) Toulouse, Andrea; Drozella, Johannes; Thiele, Simon; Giessen, Harald; Herkommer, Alois
Open Access
Distortion-free multi-element Hypergon wide-angle micro-objective by femtosecond 3D printing
(2020) Weber, Ksenia; Wang, Zhen; Thiele, Simon; Herkommer, Alois; Giessen, Harald
Open Access
H+-conducting aromatic multiblock copolymer and blend membranes and their application in PEM electrolysis
(2021) Bender, Johannes; Mayerhöfer, Britta; Trinke, Patrick; Bensmann, Boris; Hanke-Rauschenbach, Richard; Krajinovic, Katica; Thiele, Simon; Kerres, Jochen
As an alternative to common perfluorosulfonic acid-based polyelectrolytes, we present the synthesis and characterization of proton exchange membranes based on two different concepts: (i) Covalently bound multiblock-co-ionomers with a nanophase-separated structure exhibit tunable properties depending on hydrophilic and hydrophobic components’ ratios. Here, the blocks were synthesized individually via step-growth polycondensation from either partially fluorinated or sulfonated aromatic monomers. (ii) Ionically crosslinked blend membranes of partially fluorinated polybenzimidazole and pyridine side-chain-modified polysulfones combine the hydrophilic component’s high proton conductivities with high mechanical stability established by the hydrophobic components. In addition to the polymer synthesis, membrane preparation, and thorough characterization of the obtained materials, hydrogen permeability is determined using linear sweep voltammetry. Furthermore, initial in situ tests in a PEM electrolysis cell show promising cell performance, which can be increased by optimizing electrodes with regard to binders for the respective membrane material.
Open Access
Mass-producible micro-optical elements by injection compression molding and focused ion beam structured titanium molding tools
(2020) Ristok, Simon; Roeder, Marcel; Thiele, Simon; Hentschel, Mario; Guenther, Thomas; Zimmermann, André; Herkommer, Alois; Giessen, Harald
Open Access
Stitching-free 3D printing of millimeter-sized highly transparent spherical and aspherical optical components
(2020) Ristok, Simon; Thiele, Simon; Toulouse, Andrea; Herkommer, Alois; Giessen, Harald
Open Access
Synthesis and characterization of novel perfluoro aromatic side chain sulfonated PSU ionomers
(2024) Martschin, Philipp; Atanasov, Vladimir; Thiele, Simon; Kerres, Jochen
Polyethersulfone (PSU) as a commercially available polymer offers many different opportunities for functionalization for diverse fields of application, for example, electrophilic substitutions like sulfonation and bromination or nucleophilic reactions such as lithiation. This study presents three different polysulfone derivatives, first functionalized by a lithiation reaction, followed by a reaction with carbonyl compounds containing pentafluorophenyl groups. In the last step, the pentafluorophenyl moieties of the modified PSU were sulfonated by thiolation and subsequent oxidation to sulfonic acid groups. Those novel PSU derivatives were characterized by NMR, DSC, TGA, GPC, and titration. Based on these ionomers, we show the fabrication of pure and acid-base blend membranes with promising proton conductivities. These novel sulfonic acid groups containing materials are potentially promising candidates for membranes or ionomers in electrochemical applications such as proton exchange membrane fuel cells (PEMFCs), proton exchange membrane water electrolysis (PEMWEs), or redox flow batteries (RFBs).
Open Access
Tailored nanocomposites for 3D printed micro-optics
(2020) Weber, Ksenia; Werdehausen, Daniel; König, Peter; Thiele, Simon; Schmid, Michael; Decker, Manuel; Oliveira, Peter William de; Herkommer, Alois; Giessen, Harald
Open Access
Ultrathin monolithic 3D printed optical coherence tomography endoscopy for preclinical and clinical use
(2020) Li, Jiawen; Thiele, Simon; Quirk, Bryden C.; Kirk, Rodney W.; Verjans, Johan W.; Akers, Emma; Bursill, Christina A.; Nicholls, Stephen J.; Herkommer, Alois; Giessen, Harald; McLaughlin, Robert A.