A5077894541- Solid State Laser Technologies
- Civil and Structural Engineering Research
- Semiconductor Lasers and Optical Devices
- Laser Design and Applications
- Structural Engineering and Materials Analysis
- Metal Forming Simulation Techniques
- Concrete Corrosion and Durability
- GaN-based semiconductor devices and materials
- Laser Material Processing Techniques
- Fluid Dynamics and Turbulent Flows
- Advanced Surface Polishing Techniques
- Real-time simulation and control systems
- Data Analysis with R
- Metal Alloys Wear and Properties
- Electric and Hybrid Vehicle Technologies
- Advanced Sensor Technologies Research
- Turbomachinery Performance and Optimization
- Advanced Combustion Engine Technologies
- Metallurgy and Material Forming
- Lanthanide and Transition Metal Complexes
- Vehicle Dynamics and Control Systems
- Photonic Crystal and Fiber Optics
- Marine Ecology and Invasive Species
- Advanced machining processes and optimization
- Marine Biology and Environmental Chemistry
University of Wisconsin–Madison
2024-2025
Laserline (Germany)
2012-2023
University of Stuttgart
2014-2022
Chemnitz University of Technology
2011-2021
University of Leeds
2021
Ludwig-Maximilians-Universität München
2021
University of Bremen
2021
Friedrich-Alexander-Universität Erlangen-Nürnberg
2020
Springer Nature (Germany)
2016
Technische Universität Dresden
2015
The availability of high-power blue diode-lasers established a new class laser sources for materials processing recently. With the significantly shorter wavelength compared to conventional applications are moving into range feasible. There is strong demand welding with copper due change from internal combustion engines electric drives, which even prompts manufacturers find complex solutions obtain source in where shows higher absorption. appearance diode-laser bars range, proven optical...
Cluster-randomized trials (CRTs) are a well-established class of designs for evaluating large-scale, community-based research questions. An essential task in planning these is determining the required number clusters and cluster sizes to achieve sufficient statistical power detecting clinically relevant effect size. Compared methods average treatment (ATE) entire study population, there more recent development sample size testing heterogeneity effects (HTEs), i.e., modification by...
Asset administration shells constitute a standardized, technical realization of digital twins and enable unified description important information within production site for safe, continuous joint planning intralogistics manufacturing processes. In this paper, we show how an service infrastructure based on asset can be used to provide online-planners with unified, i.e. manufacturer-independent facets respective control interfaces involved assets, such as collaborative robots. To end,...
The accumulation of organisms on submersed objects, so-called biofouling, is a serious problem technically relevant surfaces and causes enormous economic damage. In the case shipping, it also leads to increased fuel consumption therefore elevated CO2 emissions. Within context this work, an experimental setup was built achieve laser-induced lethal damage soft fouling microorganisms. At same time, influence laser treatment two commercial anti-fouling coatings evaluated by determining...
High strength steels enable new solutions for weight optimized car bodies without sacrificing crash safety. However, cold forming of these is limited due to the need high press capacity, increased tool wear, and limitations in possible geometries. One can compensate drawbacks by local heat treatment blanks. In high-deformation areas material reduced plasticity diode laser irradiation. Local with radiation could also yield key benefits applicability hardened parts. not desired all over part....
More and more applications are using GaN laser diodes. Visible blue devices well established light sources for converter based business projection of several thousand Lumens. Additional laser-based concepts like near-to-eye push device requirements above heretofore limits. In 2017, threshold currents 10 20mA were reported single mode green laser, respectively. We will present a drastic reduction R&D samples by than factor 2 down to 10mA. also discuss turn-on delay as limiting modulation...
Model-based predictive maintenance using high-frequency in-flight data requires digital twins that can model the dynamics of their physical twin with high precision. The models need to be fast and dynamically updatable. Machine learning offers possibility address these challenges in modeling transient performance aero engines. During operation, heat transferred between engine’s structure annulus flow plays an important role. Diabatic is demonstrated non-dimensional transfer maps extend...
Sonar sensors are universally applied in autonomous vehicles such as robots and driverless cars they inexpensive, energy-efficient, provide accurate range measurements; however, have some limitations. Their measurements can lead to ambiguous estimates echo clutter hamper target detection. In nature, echolocating bats experience similar problems when searching for food, especially if their food source is close vegetation, the case gleaning nectar-feeding bats. However, nature has come up with...
The authors have demonstrated efficient TEM00 operation of the Nd:YVO4 rod laser, one-end-pumped by a one-fibre-coupled diode laser. A 11.6 W linearly polarised laser output with an optical efficiency 54% in mode has been achieved.
A high-power blue laser source was long-awaited for processing materials with low absorption in the near infrared (NIR) spectral range like copper or gold. Due to huge progress of GaN-based semiconductors, performance diode-lasers has made a major step forward recently. With availability unprecedented power levels at cw-operating emitting 450 nm, it possible set up diode-laser address these conventional applications and probably beyond that establish completely new utilizations lasers....
Industrial material processing like cutting or welding of metals is rather energy efficient using direct diode pumped solid state lasers. However, many applications cannot be addressed by established infrared laser technology due to fundamental properties the workpiece: For example materials copper gold have too low absorption in near wavelength range processed efficiently use existing high power systems. The huge interest enable kW systems with more suitable wavelengths blue spectral...
Monolithic linear arrays of diode lasers, also known as laser bars, are the basic elements for most high-power applications such solid-state pumping or material processing. Cylindrical microlenses used fast- axis collimators 10-mm bars require very high angles aperture (up to 100 degree FW1/e2, equivalent a numerical approx. 0.8) capture emitted power. For efficient longitudinal rods, narrow focusing radiation (fiber coupling, processing), high- quality with small lens aberrations necessary...
A technique for coupling the radiation of a high-power diode laser bar into one multimode fiber with high efficiency, easy alignment requirements and low manufacturing costs is demonstrated using single 400 micrometers core diameter. The principal item fiber-coupling system pair micro step-mirrors--a novel design beam shaping. overall efficiency from diode-laser to 71% 20 W cw power through fiber. Polarization wavelength multiplexing renders scaleable higher output which makes it highly...
After conventional forming processes, the residual stress distribution in wires is frequently unfavorable for subsequent such as bending operations. High tensile stresses typically occur near wire surface and normally limit further processability of material. Additional heat treatment operations or shot peening are often used to influence material after manufacturing, which time- energy-consuming. This paper presents an approach influencing by modifying process, especially regarding die...
Blue high-power semiconductor lasers have increased greatly in performance over the recent decade enabling new application fields from high brightness projection up to materials processing beyond 1000W output power systems. Base for best system is optimal chip design and reliability of device. In this paper optimization blue laser bars will be shown: contrast IR with lateral emitter fill factors 50%, optimum maximum efficiency GaN currently at very low range 10%. Laser bar designs ranging 5%...
Since the first blue lasers made from GaN-based semiconductors reached power levels making them suitable for industrial applications a few years ago, users where asking more power. Quickly, output powers fiber-coupled diode increased several hundred watts in early 2018 [1] to 1000 W 2019 [2] and even 2000 2020 [3]. But lifetime has always been an object of concern since diode-laser moved out TO-can enter high world. As part research project "FoulLas", which started is funded by German...
The topic is the interpretation of measured values, a theoretical model and investigation critical parameters affecting stress sensitive permeability. computer aided biaxial compression testing device allows determination permeability, while at same time applied measured. Compressive vertical to magnetisation an equivalent tensile parallel vice versa. rise permeability can be found in crystal anisotropy which partly compensated by increasing magnetostrictive energy density. After reaching...
Thyratrons are limited in lifetime and maximum repetition rate. For some applications it is necessary to replace the thyratron by a semiconductor switch. Therefore compress pulses nonlinear inductances. In magnetic pulse compression network three main losses exist. principle copper conducting can be infinitely reduced. The capacitors very small principally also reduced an infinite degree. But core different. Due fact that material magnetized from one saturation other, depend only on...
InGaN lasers in the blue and green wavelength range have opened a wide variety of applications past years, which all require unique properties employed laser chips. In this paper we will show design process developments for various designs, each optimized its specific application. For are very sensitive to energy consumption, like mobile AR/VR devices, investigated chips with resonator lengths as short 50 μm. To achieve this, developed an etched facets technology overcome challenges scribing...
A technique for coupling the output of a high-power diode laser bar into one multimode fiber with high efficiency, easy alignment requirements and low manufacturing costs is demonstrated using single 400 μm core diameter. This comprises two micro step-mirrors beam shaping. The overall efficiency from diode-laser to 71% 20 W cw power through fiber.