TY - GEN A1 - Möllmann, Klaus-Peter A1 - Vollmer, Michael T1 - The Basics Science and History of Thermal Imaging Y1 - 2014 N1 - Thermal Imaging Conference TIC2014 in Las Vegas/Nevada (USA) 02. − 06.06.2014 ER - TY - JOUR A1 - Wang, Jing A1 - Harth, Kirsten A1 - Puzyrev, Dmitry A1 - Stannarius, Ralf T1 - The effect of obstacles near a silo outlet on the discharge of soft spheres JF - New Journal of Physics KW - fluid dynamics Y1 - 2022 U6 - https://doi.org/10.1088/1367-2630/ac8bea VL - 24 PB - IOP ER - TY - JOUR A1 - Vollmer, Michael T1 - The evolution of IR imaging: What’s next? JF - Laser Focus World Magazine N2 - The vast majority of all human sensory inputs occur through our eyes. Light from direct sources or scattered light from objects enters our eyes and is focused onto the retina. The resulting signals are interpreted by the brain, which leads to the perception of the image of the observed objects. Although quite efficient for our daily life, many technological applications require sensor properties beyond the characteristics of our eyes. A major limitation regarding microscopic objects is spatial resolution, which is overcome by microscopes. Time resolution can be dealt with using either time-lapse or high-speed cameras. Finally, eyes only detect visible radiation within the wavelength range from about 380 nm to 780 nm. Changing the detected spectral range of electromagnetic radiation can dramatically enhance our vision. Shorter wavelengths such as x-rays are valuable tools for medical imaging, while ultraviolet (UV) imaging is used for forensics. Longer-wavelength thermal radiation used for imaging is often defined within spectral ranges, characterized by the photoelectric detector materials used and the respective atmospheric windows. Y1 - 2022 UR - https://www.laserfocusworld.com/detectors-imaging/article/14233175/the-evolution-of-ir-imaging-whats-next SP - 23 EP - 26 PB - endeavor business media ER - TY - JOUR A1 - Aman, Sergej A1 - Aman, Alexander A1 - Hintz, Werner A1 - Trüe, Michael A1 - Veit, Peter A1 - Hirsch, Sören T1 - The Exfoliation of Graphite Particles in the Vibratory Disk Mill JF - Chemie Ingenieur Technik Y1 - 2017 U6 - https://doi.org/10.1002/cite.201600124 VL - 89 IS - 9 SP - 1185 EP - 1191 ER - TY - JOUR A1 - Vollmer, Michael T1 - The freezing of lakes in winter JF - European Journal of Physics N2 - Freezing of lakes is described using a simplified one-dimensional model, which gives ice thickness, ice growth rates, and ice surface temperature as a function of time. Model data for a specific lake with known meteorological conditions are compared to estimated ice thickness using a simple optical method. Finally, more advanced potential students projects are briefly discussed and results of a numerical solution are compared to the simplified model. Y1 - 2019 UR - https://iopscience.iop.org/article/10.1088/1361-6404/ab07f8 U6 - https://doi.org/10.1088/1361-6404/ab07f8 SN - 1367-2630 IS - Ausgabe: 3/ Band: 40 PB - IOP Publishing ER - TY - CHAP A1 - Vollmer, Michael A1 - Möllmann, Klaus-Peter T1 - The magic of the invisible: using IR imaging in physics education T2 - In: InfraMation proceedings / Infrared Training Center. - Vol. 14 (2013) Y1 - 2013 ER - TY - GEN A1 - Vollmer, Michael T1 - The magic of the invisible: using IR imaging in physics education Y1 - 2013 ER - TY - JOUR A1 - Vollmer, Michael A1 - Möllmann, Klaus-Peter A1 - Shaw, Joseph A. T1 - The optics and physics of near infrared imaging JF - Proceedings of SPIE 9793, Education and Training in Optics and Photonics: ETOP 2015, 97930Z (October 8, 2015) N2 - abstract A large part of photonics research and development, as well as commercial applications such as optical data transmission or infrared thermal imaging, occurs in the infrared spectral range between 0.8 μm and 15 μm. However, relatively little material is so far available for experimentally teaching the physics and optics of this spectral range. We report a respective new approach in the near infrared (NIR) range between 0.8 μm and 1.7 μm that allows visualization of a number of fascinating physics phenomena. First, we use the near-infrared sensitivity of silicon-based detectors in rather inexpensive video cameras and digital single-lens reflex cameras by removing the infrared-blocking filter and replacing it with a visible-radiation blocking filter. Second, we utilize modern NIR cameras based on InGaAs detectors. With both camera types we illustrate and explain a number of physics concepts that are especially suitable for curricula in optics and photonics. Examples include the strangely bright appearance of vegetation, contrast enhancement between clouds and sky, the initially surprising differences of optical material properties between the VIS and NIR range, the possibilities of visualizing buried hidden structures and texts, and recent medical applications to locate blood vessels below the skin. © (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only. Y1 - 2015 U6 - https://doi.org/10.1117/12.2223094 ER - TY - JOUR A1 - Lachowski, Krzysztof A1 - Hammermeister, Florian A1 - Halenz, Bastian A1 - Lieckefett, Florian A1 - Götze, Thomas A1 - Prill, Robert A1 - Becker, Roland T1 - The Patellostabilometer: A New Device for Quantification of Mediolateral Patella Displacement JF - Sensors N2 - Mediolateral patella displacement is of interest for diagnostics and clinically relevant research questions. Apart from manual testing, no standardized method is currently available. Proper quantification of patella mobility is necessary to better understand pathologies at the patellofemoral joint. Patella mobility was assessed in 25 healthy individuals using a Patellostabilometer, a new prototype instrument for quantification of the mediolateral patella displacement. The participants underwent measurements of the mediolateral displacement three times using the Patellostabilome- ter. A maximal force of 10 N was applied for patella movement. Additionally, leg length and circumference of the knee, upper- and lower-leg were measured. Lateral patella displacement of 18.27 ± 3.76 mm (range 15.85–20.64 mm, interquartile range (IQR) of 4.79) was measured. The medial patella displacement showed 24.47 ± 6.59 mm (range 19.29–29.76 mm, IQR of 10.47). The test–retest measurement error was 2.32 ± 1.76 mm (IQR of 2.38 mm), with five outliers. There was greater test–retest variability between the measurements of the medial displacement compared to the lateral one. The test–retest variability reached 7% of the patella displacement. Other parameters provided no significant correlations. Based on the natural patellofemoral mobility, a precise and clinically relevant quantification of patella mobility is allowed. Y1 - 2023 UR - https://www.mdpi.com/1424-8220/23/3/1274 U6 - https://doi.org/https://doi.org/10.3390/s23031274 IS - 23 (3) PB - MDPI ER - TY - JOUR A1 - Mangold, Klaus A1 - Shaw, Joseph A. A1 - Vollmer, Michael T1 - The physics of near-infrared photography JF - In: European journal of physics 34 (2013) 6, S51-S71 N2 - The physics behind the sometimes strange effects and 'unnatural' appearance of near-infrared (NIR) photographs is discussed in terms of reflection, absorption and transmission of NIR radiation with the respective objects. Besides discussing how NIR cameras work, several visible and NIR photograph pairs are presented, which include vegetation, natural water, clouds, the sky, and humans. In addition, some physics-oriented experimental NIR images are presented which clearly demonstrate some of the basic physics behind some of these awesome sights. Y1 - 2013 U6 - https://doi.org/doi:10.1088/0143-0807/34/6/S51 SP - S51 EP - S71 ER - TY - JOUR A1 - Stannarius, Ralf A1 - Harth, Kirsten T1 - The structure of disintegrating defect clusters in smectic C freely suspended films JF - Soft Matter N2 - Disclinations or disclination clusters in smectic C freely suspended films with topological charges larger than one are unstable. They disintegrate, preferably in a spatially symmetric fashion, into single defects with individual charges of +1, which is the smallest positive topological charge allowed in polar vector fields. While the opposite process of defect annihilation is well-defined by the initial defect positions, disintegration starts from a singular state and the following scenario including the emerging regular defect patterns must be selected by specific mechanisms. We analyze experimental data and compare them with a simple model where the defect clusters adiabatically pass quasi-equilibrium solutions in one-constant approximation. It is found that the defects arrange in geometrical patterns that correspond very closely to superimposed singular defect solutions, without additional director distortions. The patterns expand by affine transformations where all distances between individual defects scale with the same time-dependent scaling factor proportional to the square-root of time. Y1 - 2023 UR - https://pubs.rsc.org/en/content/articlelanding/2023/sm/d3sm00808h U6 - https://doi.org/https://doi.org/10.1039/d3sm00808h IS - 19 SP - 6109 EP - 6115 PB - Royal Society of Chemistry ER - TY - JOUR A1 - Planinsic, G. A1 - Vollmer, Michael T1 - The surface to volume ratio in thermal physics: from cheese cube physics to animal metabolism JF - In: European Journal of Physics 29 (2008), 369-384 Y1 - 2008 SN - 0143-0807 SP - 369 EP - 384 ER - TY - JOUR A1 - Vollmer, Michael A1 - Möllmann, Klaus-Peter T1 - The tablecloth pull revisited JF - Physics Education 50 (2015) 3 N2 - Abstract A very old and well-known magical trick is the so-called tablecloth pull. A table is covered with a tablecloth, on top of which are certain objects. The task is to remove the tablecloth while the objects—which must not be touched—stay on top of the table. This article describes the physics behind the experiment, and presents examples recorded with high-speed cameras. Y1 - 2015 SP - 324 EP - 328 ER - TY - GEN A1 - Möllmann, Klaus-Peter T1 - Theorie und Praxis der Strahlungsthermometrie Y1 - 2013 N1 - Eingeladener Vortrag Raytek IR-Tage Berlin, 11.06.2013 ER - TY - GEN A1 - Vollmer, Michael T1 - There is more to see than eyes can detect Y1 - 2002 ER - TY - JOUR A1 - Karstädt, Detlef A1 - Möllmann, Klaus-Peter A1 - Pinno, Frank A1 - Vollmer, Michael T1 - There is more to see than eyes can detect : visualization of energy transfer processes and the laws of radiation for physics education JF - In: The Physics Teacher 39 (2001), 371-376 Y1 - 2001 SP - 371 EP - 376 ER - TY - JOUR A1 - Karstädt, Detlef A1 - Möllmann, Klaus-Peter A1 - Pinno, Frank A1 - Vollmer, Michael T1 - There is more to see than eyes can detect: visualization of energy transfer processes and the laws of radiation for physics education JF - In: The Physics Teacher 39 (2001), 371-376 Y1 - 2001 SP - 371 EP - 376 ER - TY - CHAP A1 - Möllmann, Klaus-Peter A1 - Vollmer, Michael T1 - Thermal effects due to focused light from glass fronts T2 - InfraMation proceedings. - Vol. 13 (2012) Y1 - 2012 ER - TY - CHAP A1 - Möllmann, Klaus-Peter A1 - Karstädt, Detlef A1 - Pinno, Frank A1 - Vollmer, Michael T1 - Thermal image quality – Visualization of spatial and thermal resolution in thermal imaging T2 - In: InfraMation proceedings Vol. 7 (2006), 79-92 Y1 - 2006 SP - 79 EP - 92 ER - TY - RPRT A1 - Kügler, H. A1 - Möller, F. A1 - Goecke, Sven-Frithjof A1 - Vollertsen, F. T1 - Thermisches Fügen höchstfester Stähle T2 - Schweissen und Schneiden Y1 - 2015 SN - 0036-7184 VL - 67 IS - 12 SP - 744 ER -