TY - CHAP A1 - Leiter, Nina A1 - Wohlschlaeger, Maximilian A1 - Versen, Martin A1 - Laforsch, Christian T1 - Non-destructive differentiation of treated and non-treated wood using fluorescence lifetime imaging microscopy T2 - Sensors and Measuring Systems; 21th ITG/GMA-Symposium Y1 - 2022 SP - 1 EP - 6 ER - TY - CHAP A1 - Wohlschlaeger, Maximilian A1 - Versen, Martin A1 - Laforsch, Christian T1 - A novel approach to optically detect microplastic in an environmental matrix with Rapid-FLIM T2 - Sensors and Measuring Systems; 21th ITG/GMA-Symposium Y1 - 2022 SP - 1 EP - 6 ER - TY - CHAP A1 - Höltl, Stefan A1 - Kneißl, Matthias A1 - Versen, Martin T1 - Parallel Delta-Sigma ADC modulation for performance increase of position sensors in industrial applications T2 - 2021 IEEE Sensors Applications Symposium (SAS) N2 - A parallel design concept of Delta-Sigma modulators that optimizes the resolution and the bandwidth for a highly dynamic position control in industrial applications. The idea is realized on a printed circuit board and tested by using a comprehensive measurement setup. The effective number of bits is increased by 2.5 bits at a fixed frequency. For a constant resolution, the design approach allows smaller filter lengths and a decrease of the delay by 25%. KW - Delta-Sigma KW - ADC KW - parallelization KW - characterization KW - effective resolution KW - bandwidth Y1 - 2021 U6 - https://doi.org/10.1109/SAS51076.2021.9530099 SP - 1 EP - 5 ER - TY - CHAP A1 - Wohlschläger, Maximilian A1 - Holst, Gerhard A1 - Versen, Martin T1 - A novel approach to optically distinguish plastics based on fluorescence lifetime measurements T2 - 2020 IEEE Sensors Applications Symposium (SAS) N2 - In medical and biological research, fluorescence lifetime measurements and fluorescence lifetime imaging is already a part of the standardized analysis procedures. As first investigations have shown, polymers can be identified using fluorescence lifetime imaging and an evaluation algorithm. Thus, this contribution pursues a novel approach for the direct differentiation of four polymers with fluorescence lifetime imaging. Therefore, the evaluation algorithm is extended to compare several fluorescence lifetime images to prove that a distinction is possible. Y1 - 2020 U6 - https://doi.org/10.1109/SAS48726.2020.9220084 SP - 1 EP - 6 ER - TY - CHAP A1 - Wohlschläger, Maximilian A1 - Versen, Martin A1 - Laforsch, Christian T1 - Non-destructive evaluation of treated polyethylene terephthalate films by fluorescence lifetime imaging T2 - 2021 IEEE Sensors Applications Symposium (SAS) N2 - The fluorescence decay time allows to identify and distinguish polymers from each other. Three differently treated biaxially-oriented polyethylene terephthalate films are examined with two excitation wavelengths of 445 and 488nm. The fluorescence decay time is dependent of the treatment method of the films and is a means for identification. KW - polymer KW - polymer identification KW - fluorescence lifetime imaging KW - fluorescence KW - FD-FLIM Y1 - 2021 U6 - https://doi.org/10.1109/SAS51076.2021.9530008 SP - 1 EP - 5 ER - TY - CHAP A1 - Bernöcker, Anton A1 - Leiter, Nina A1 - Wohlschläger, Maximilian A1 - Versen, Martin T1 - Entwicklung eines neuronalen Netzwerks als Basis zur automatisierten Holzartenerkennung T2 - Tagungsband AALE 2022, 18. AALE-Konferenz. Pforzheim, 09.03.-11.03.2022 N2 - Holz ist ein vielseitig einsetzbarer nachwachsender Rohstoff. Neben seinem wirtschaftlichen Nutzen ist er für den Erhalt des Klimas unersetzlich. Eine sortenreine Sortierung für die Weiterverarbeitung von Altholz spielt für einen ressourcenschonenden Umgang eine wichtige Rolle. Um das Potenzial eines neuronalen Netzwerks basierend auf Messdaten der bildgebenden Fluoreszenzabklingzeitmessung für die Altholzsortierung aufzuzeigen, wurden zwei unterschiedliche Klassifikationsansätze auf Basis der Programmiersprache Python gewählt. Die Ergebnisse zeigen, dass die bildbasierte Klassifizierung der Holzart mit einer Genauigkeit von 47,36 % noch ausbaufähig ist. Eine datenbasierte Klassifizierung der Holzart mit einer Identifikationsgenauigkeit von 98,28 % ist dagegen vielversprechend. KW - FD-FLIM KW - Fluoreszenz KW - Fluoreszenzabklingzeit KW - Holzart KW - Neuronales Netz KW - Klassifizierung Y1 - 2022 U6 - https://doi.org/https://doi.org/10.33968/2022.11 SP - 115 EP - 124 ER - TY - CHAP A1 - Leiter, Nina A1 - Wohlschläger, Maximilian A1 - Versen, Martin T1 - Frequency-domain fluorescence lifetime imaging as method to analyze wood structures T2 - 2022 Conference on Lasers and Electro-Optics (CLEO) Y1 - 2022 SP - 1 EP - 2 ER - TY - CHAP A1 - Wohlschläger, Maximilian A1 - Versen, Martin ED - Bauer, Benedict ED - Wittenberg, Carsten T1 - Bestimmung einer Quanteneffizienz für das automatisierte Sortieren von Kunststoffen durch Fluoreszenz T2 - AALE 2019 - Autonome und intelligente Systeme in der Automatisierungstechnik 16. Fachkonferenz KW - Quanteneffizienz KW - Fluoreszenz Y1 - 2019 SN - 978-3-8007-4860-0 SP - 179 EP - 187 PB - VDE Verlag CY - Berlin ER - TY - CHAP A1 - Kneißl, M. A1 - Versen, Martin ED - Bauer, Benedict ED - Wittenberg, Carsten T1 - Erhöhung der Bandbreite eines Stromregelkreises durch Hadamard-Modulation T2 - AALE 2019 - Autonome und intelligente Systeme in der Automatisierungstechnik 16. Fachkonferenz KW - Hadamard-Modulation Y1 - 2019 SN - 978-3-8007-4860-0 SP - 277 EP - 285 PB - VDE Verlag CY - Berlin ER - TY - CHAP A1 - Wohlschläger, Maximilian A1 - Holst, G. A1 - Versen, Martin T1 - A novel approach to optically distinguish plastics based on fluorescence lifetime measurements T2 - 2020 IEEE Sensors Applications Symposium (SAS), Kuala Lumpur, Malaysia KW - fluorescence Y1 - 2020 SP - 1 EP - 6 ER - TY - CHAP A1 - Wohlschläger, Maximilian A1 - Versen, Martin A1 - Langhals, H. T1 - A method for sorting of plastics with an apparatus specific quantum efficiency approach T2 - 2019 IEEE Sensors Applications Symposium (SAS) N2 - Today, the automatic separation of polymers from each other in an industrial scale is an unsolved problem. In laboratory environments, two methods are known whereby plastic is sorted either by color or by fluorescence decay time measurements that require fast synchronization and thus expensive equipment. A simple and pragmatic process is proposed to separate plastics from each other: all fluorescent photons are counted in relation to the absorbed photons. A theoretical model and an experimental setup are built in order to determine an apparatus specific quantum efficiency. KW - polymer KW - plastic sorting KW - fluorescence KW - quantum efficiency Y1 - 2019 UR - https://ieeexplore.ieee.org/document/8706034 ER - TY - CHAP A1 - Maniyattu, Georgekutty Jose A1 - Geegy, Eldho A1 - Leiter, Nina A1 - Wohlschläger, Maximilian A1 - Versen, Martin A1 - Laforsch, Christian T1 - Development of a neural network to identify plastics using Fluorescence Lifetime Imaging Microscopy T2 - 2022 IEEE Sensors Applications Symposium (SAS) N2 - Plastics have become a major part of human’s daily life. An uncontrolled usage of plastic leads to an accumulation in the environment posing a threat to flora and fauna, if not recycled correctly. The correct sorting and recycling of the most commonly available plastic types and an identification of plastic in the environment are important. Fluorescence lifetime imaging microscopy shows a high potential in sorting and identifying plastic types. A data-based and an image-based classification are investigated using python programming language to demonstrate the potential of a neural network based on fluorescence lifetime images to identify plastic types. The results indicate that the data-based classification has a higher identification accuracy compared to the image-based classification. KW - fluorescence lifetime imaging KW - FLIM KW - neural networks KW - plastic identification Y1 - 2022 U6 - https://doi.org/10.1109/SAS54819.2022.9881372 SP - 1 EP - 6 ER - TY - JOUR A1 - Leiter, Nina A1 - Wohlschläger, Maximilian A1 - Versen, Martin A1 - Laforsch, Christian T1 - An algorithmic method for the identification of wood species and the classification of post-consumer wood using fluorescence lifetime imaging microscopy JF - Journal of Sensors and Sensor Systems N2 - In this contribution the frequency domain fluorescence lifetime imaging microscopy (FD-FLIM) technique is evaluated for post-consumer wood sorting. The fluorescence characteristics of several wood samples were determined, whereby two excitation wavelengths (405 and 488 nm) were used. The measured data were processed using algorithmic methods to identify the wood species and post-consumer wood category. With the excitation wavelength of 405 nm, 16 out of 19 samples could be correctly assigned to the corresponding post-consumer wood category by means of the fluorescence lifetimes. Thus, the experimental results revealed the high potential of the FD-FLIM technique for automated post-consumer wood sorting. Y1 - 2022 U6 - https://doi.org/10.5194/jsss-11-129-2022 VL - 11 IS - 1 SP - 129 EP - 136 ER - TY - CHAP A1 - Wohlschläger, Maximilian A1 - Versen, Martin A1 - Laforsch, Christian T1 - Optical identification of car tire particles on soil using fluorescence lifetime imaging microscopy T2 - Optical Sensors and Sensing Congress 2022 (AIS, LACSEA, Sensors, ES), Technical Digest Series (Optica Publishing Group, 2022) N2 - Tire wear is one of the major contributors of environmental pollution by microplastic. FD-FLIM in combination with an image processing algorithm are successfully applied to detect tyre wear on soil. KW - Diode lasers KW - Fluorescence lifetime imaging KW - Image processing KW - Image processing algorithms KW - Phase modulation KW - Phase shift Y1 - 2022 U6 - https://doi.org/10.1364/ES.2022.ETu3H.3 SP - ETu3H.3 ER - TY - JOUR A1 - Leiter, Nina A1 - Wohlschläger, Maximilian A1 - Versen, Martin T1 - Analysis of the phase-dependent fluorescence decay time of treated wood using FD-FLIM JF - tm - Technisches Messen N2 - For sustainable handling of wood and high material utilization, post-consumer wood has to be sorted by post-consumer wood categories in Germany. The non-destructive FD-FLIM method could improve the wood recycling process by automatic classification of waste wood into post-consumer wood classes. Thus, the phase-dependent fluorescence decay time of treated wood is analysed in this study to obtain the impact of the treatment on the fluorescence decay time. It is shown that treated and untreated wood can be differentiated using the fluorescence decay time, although the state-of-the-art theoretical fluorescence decay time differs from the experimentally determined fluorescence decay time. N2 - Für einen nachhaltigen Umgang mit Holz und eine hohe stoffliche Verwertung muss Altholz in Deutschland nach Altholzklassen sortiert werden. Die zerstörungsfreie FD-FLIM-Methode könnte den Holzrecyclingprozess durch eine automatische Klassifizierung von Altholz in Altholzklassen verbessern. Daher wird in dieser Studie die phasenabhängige Fluoreszenzabklingzeit von behandeltem Holz analysiert, um den Einfluss der Behandlung auf die Fluoreszenzabklingzeit zu ermitteln. Es wird gezeigt, dass behandeltes und unbehandeltes Holz anhand der Fluoreszenzabklingzeit unterschieden werden kann, auch wenn die nach dem Stand der Forschung theoretische Fluoreszenzabklingzeit von der experimentell ermittelten Fluoreszenzabklingzeit abweicht. KW - fluorescence KW - decay time KW - FD-FLIM KW - lifetime KW - wood Y1 - 2023 U6 - https://doi.org/10.1515/teme-2022-0114 VL - 90 IS - 6 SP - 401 EP - 406 ER - TY - CHAP A1 - Dietlmeier, Maximilian A1 - Rajan, Aromal Somarajan A1 - Leiter, Nina A1 - Wohlschläger, Maximilian A1 - Versen, Martin T1 - Klassifizierung von Altholz durch FD-FLIM Bilder mit neuronalen Netzen T2 - Tagungsband AALE 2023 N2 - Holz ist eine der wichtigsten erneuerbaren Ressourcen und kann recycelt werden, wobei derzeit nur unbehandeltes Holz in mehreren Lebenszyklen verwendet werden kann. Allerdings werden in Altholzsortieranlagen meist behandeltes und unbehandeltes Altholz gemischt angeliefert und es gibt keine automatische Klassifizierung zur sortenreinen Sortierung. Frühere Studien zeigen, dass behandelte und unbehandelte Holzproben mit Hilfe von bildgebender Fluoreszenzabklingzeit Mikroskopie unterschieden werden können. Um den Prozess der Klassifizierung von Altholz anhand von Fluoreszenzabklingzeitbildern zu automatisieren, werden zwei neuronale Netzwerke (NN) evaluiert. Das erste NN ist ein MLP (Multi Layer Perceptron), das das Altholz anhand von Erwartungswert und Standardabweichung eines Fluoreszenzabklingzeitbildes klassifiziert. Das zweite untersuchte NN ist ein CNN (Convolutional Neural Network), das das Holz direkt anhand der Fluoreszenzabklingzeitbilder klassifiziert. Beide Netzwerke sind in Python implementiert, um die spätere Verwendung in einem automatischen Klassifizierungs- und Sortierprozess zu erleichtern. Die Evaluation der NN zeigt vielversprechende Ergebnisse zur automatisierten Klassifikation von Altholz. Y1 - 2023 U6 - https://doi.org/10.33968/2023.24 ER - TY - CHAP A1 - Wohlschläger, Maximilian A1 - Holst, Gerhard A1 - Versen, Martin A1 - Laforsch, Christian T1 - An optical method to differentiate wood from polymers using fluorescence lifetime imaging microscopy T2 - OSA Optical Sensors and Sensing Congress 2021 (AIS, FTS, HISE, SENSORS, ES) (2021), paper EW4G.6 N2 - In this contribution investigations with fluorescence lifetime imaging microscopy (FLIM) are made to optically distinguish polymers and wood. The results show that the distinction and identification is possible in a graphical and calculative way. Y1 - 2021 U6 - https://doi.org/10.1364/ES.2021.EW4G.6 SP - EW4G.6 ER - TY - CHAP A1 - Leiter, Nina A1 - Wohlschläger, Maximilian A1 - Auer, Veronika A1 - Versen, Martin A1 - Laforsch, Christian T1 - An algorithmic method to identify multiple wood species in a single image by their specific fluorescence lifetimes T2 - OSA Imaging and Applied Optics Congress 2021 (3D, COSI, DH, ISA, pcAOP) (2021), paper CF2B.3 N2 - Fluorescence lifetime imaging microscopy (FLIM) combined with an image processing algorithm is successfully used for the optical identification and areal separation of three wood species of maple, larch and nut in a single taken image. Y1 - 2021 U6 - https://doi.org/10.1364/COSI.2021.CF2B.3 SP - CF2B.3 ER - TY - CHAP A1 - Seehuber, S. A1 - Crämer, P. A1 - Kipfelsberger, S. A1 - Versen, Martin T1 - EtherCAT Gateway für eine Arduino basierte Luftqualitäts-Messung zur Visualisierung an eine Beckhoff SPS T2 - Tagungsband 3. Symposium Elektronik und Systemintegration ESI KW - EtherCAT Gateway KW - Beckhoff SPS Y1 - 2022 U6 - https://doi.org/10.57688/366 SP - 98 EP - 106 ER - TY - CHAP A1 - Thomas, Amal A1 - Saleem, Shaif A1 - Leiter, Nina A1 - Dietlmeier, Maximilian A1 - Wohlschläger, Maximilian A1 - Versen, Martin A1 - Laforsch, Christian A1 - Schwarz, Jonas A1 - Auer, Veronika A1 - Risse, Michael T1 - Frequency Domain Fluorescence Lifetime Imaging Microscopy (FD-FLIM) analysis of Quercus robur samples for origin differentiation purposes T2 - Optica Sensing Congress 2023 N2 - The fast classification and identification of plastics presents a significant challenge. The study assesses the suitability of a Multilayer Perceptron to classify and identify commonly found plastic types using Rapid-FLIM, achieving an accuracy of 88.33%. @inproceedingsSchwarz:23, Increasing demand for wood products requires methods to determine its harvest origin and ensure sustainable and legal sourcing. In 15 out of 21 cases, the origin of Quercus robur was differentiable in FD-FLIM studies. KW - Fluorescence KW - Microscopy KW - Fluorescence lifetime imaging KW - Phase shift KW - Laser sources KW - Neural networks KW - Positron emission tomography KW - Raman spectroscopy KW - Bandpass filters Y1 - 2023 ER -