Working group
Femtosecond laser microstructured steel surface (scanning electron microscope micrograph)
Femtosecond laser nanostructured silicon surface (scanning electron microscope micrograph)
The working group uses lasers with pulse durations ranging from the femtosecond to the nanosecond regime to perform research projects concerned with laser safety, materials processing, and preservation of cultural heritage.
The increasing spread of laser systems in industry and research institutes is accompanied by efforts for the improvement of optical components ensuring a reliable guidance of laser beams and activities to enhance safety at work. The working group runs projects in these fields of activity and offers testing facilities to characterize stability of filters and frames of eye protectors to laser radiation according to DIN EN 207 standard.
Femtosecond laser pulses can be utilized for structuring purposes in the micrometer range. Machining on the nanometer scale is possible using nonlinear optical laser materials interactions to achieve structures with periods smaller than the laser wavelength. In such a manner surfaces can be functionalized for technical and biomedical applications. Direct laser structuring of materials with powerful pulses needs no masks, is not restricted to flat substrates and can be applied to a large variety of materials. In recent projects laser-induced periodic surface structures (LIPSS) are studied when solids are illuminated with femtosecond laser pulses (DFG SPP1327, http://www.spp1327.de). Additionally fixing of bioactive ceramic material to titanium alloy implant surfaces (prosthesis material) by means of femtosecond laser radiation is investigated.
Laser cleaning workstation (left) and computer-based remote control (right)
Cleaning of cultural assets, especially fragile organic materials like paper, parchment and textiles is a part of the conservation process. Laser radiation as a non-contact tool offers prospects for that purpose. Laser cleaning of soiled works of art might be a supplemental method to overcome some of the limitations of traditional mechanical and chemical cleaning techniques. The working group determines laser working ranges for a safe removal of soiling from artworks trying to avoid any laser-induced modification of the original object.
The working group cooperates with national and international companies, research institutes, and associations in the following areas:
Publications
For publications, see Datebase PUBLICA
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