Articles | Volume 6, issue 2
https://doi.org/10.5194/jsss-6-351-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Special issue:
https://doi.org/10.5194/jsss-6-351-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Regular research article
| 
16 Oct 2017
Regular research article |
| 16 Oct 2017
Transmitted light pH optode for small sample volumes
Christian Rogge
CORRESPONDING AUTHOR
University of Applied Science Wildau, Department of Engineering and Natural Sciences, 15745 Wildau, Germany
Steffen Zinn
University of Applied Science Wildau, Department of Engineering and Natural Sciences, 15745 Wildau, Germany
Paolo Prosposito
University of Rome Tor Vergata, Department of Industrial Engineering and INSTM, Via del Politecnico 1, 00133 Rome, Italy
Roberto Francini
University of Rome Tor Vergata, Department of Industrial Engineering and INSTM, Via del Politecnico 1, 00133 Rome, Italy
Andreas H. Foitzik
University of Applied Science Wildau, Department of Engineering and Natural Sciences, 15745 Wildau, Germany
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Real-time active-gas imaging of small gas leaks
Non-invasive blood sugar detection by cost-effective capacitance spectroscopy
Resonant photoacoustic cells for laser-based methane detection
Fabrication of integrated polysilicon waveguides for mid-infrared absorption sensing
Near-infrared LED system to recognize road surface conditions for autonomous vehicles
Characterization of specular freeform surfaces from reflected ray directions using experimental ray tracing
Iterative feature detection of a coded checkerboard target for the geometric calibration of infrared cameras
The size-of-source effect in thermography
Method for fast determination of the angle of ionizing radiation incidence from data measured by a Timepix3 detector
Comparison of laser-based photoacoustic and optical detection of methane
Metrological characterization and calibration of thermographic cameras for quantitative temperature measurement
Detection of plastics in water based on their fluorescence behavior
Analysis of photoelastic properties of monocrystalline silicon
Evaluation of optical fibre sensors in the electrical domain
Infrared-based sensor system for contactless monitoring of wetness and ice
Miniaturized photoacoustic detection of organofluorine-based refrigerants
Characterization, calibration and validation of an industrial emissometer
Measurement of the absolute spectral responsivity in the mid-infrared based on the cryogenic electrical substitution radiometer and an optimized thermopile detector
Quantitative measurement of combustion gases in harsh environments using NDIR spectroscopy
Validation of three-component wind lidar sensor for traceable highly resolved wind vector measurements
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Crack luminescence as an innovative method for detection of fatigue damage
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Max Bergau, Thomas Strahl, Benjamin Scherer, and Jürgen Wöllenstein
J. Sens. Sens. Syst., 12, 61–68, https://doi.org/10.5194/jsss-12-61-2023, https://doi.org/10.5194/jsss-12-61-2023, 2023
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Imaging of greenhouse gases is of great interest due to global warming. A spectroscopic method, using an active illumination of the scene, is presented. It allows for imaging and concentration measurements of much smaller gas plumes and leaks than current state-of-the-art gas cameras (optical gas imaging cameras). A real-time camera is realized and validated using known methane concentrations.
Shazzad Rassel, Md Rejvi Kaysir, Abdulrahman Aloraynan, and Dayan Ban
J. Sens. Sens. Syst., 12, 21–36, https://doi.org/10.5194/jsss-12-21-2023, https://doi.org/10.5194/jsss-12-21-2023, 2023
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Diabetes Mellitus (DM) is one of the very common diseases with no viable cure. However, it can be controlled by regulating the daily sugar intake. Diabetic patients need to prick their fingers a few times a day for monitoring sugar levels. To find an alternative, researchers have been working for decades on the development of a true non-invasive technique. In this effort, we developed a cost-effective non-invasive technique for measuring blood sugar levels using capacitance spectroscopy.
Katrin Schmitt, Mara Sendelbach, Christian Weber, Jürgen Wöllenstein, and Thomas Strahl
J. Sens. Sens. Syst., 12, 37–44, https://doi.org/10.5194/jsss-12-37-2023, https://doi.org/10.5194/jsss-12-37-2023, 2023
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We present a photoacoustic sensor enabling fast, inexpensive, and highly sensitive methane detection in environmental monitoring applications. Six different T-cell designs were both theoretically and experimentally investigated. The aim was to understand the photoacoustic signal generation and resonances in relation to the different cell geometries, and determine the long-term stability and the detection limits for methane. These were below the methane background concentration in air of 1.8 ppm.
Gerald Stocker, Cristina Consani, Pooja Thakkar, Clement Fleury, Andreas Tortschanoff, Khaoula-Farah Ourak, Gerald Pühringer, Reyhaneh Jannesari, Parviz Saeidi, Elmar Aschauer, Ulf Bartl, Christoph Kovatsch, Thomas Grille, and Bernhard Jakoby
J. Sens. Sens. Syst., 11, 225–231, https://doi.org/10.5194/jsss-11-225-2022, https://doi.org/10.5194/jsss-11-225-2022, 2022
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We motivate how integrated waveguides (WGs) can be part of an on-chip non-dispersive infrared sensor system for environmental sensing. We report the hurdles in maintaining WG quality when integrating emitter and detector structures on the same chip. Thus, we introduce the concept of how to determine the intrinsic loss and a process scheme to protect WG structures from damage caused during fabrication. This could pave the way to systems for environmental sensing with a minimal footprint.
Hongyi Zhang, Shéhérazade Azouigui, Rabia Sehab, and Moussa Boukhnifer
J. Sens. Sens. Syst., 11, 187–199, https://doi.org/10.5194/jsss-11-187-2022, https://doi.org/10.5194/jsss-11-187-2022, 2022
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In this paper, a near-infrared LED system is proposed for autonomous vehicles to distinguish between weather-induced road surface conditions (dry, wet, snow, ice, water). For the LED spectra, the influence of the LED bandwidth is investigated. To assess the performance of the system for a long detection range, experiments with large incident angles are conducted. The feasibility of this system is proved via a laboratory experiment with three near-infrared LEDs and a camera.
Tobias Binkele, David Hilbig, Mahmoud Essameldin, Thomas Henning, Friedrich Fleischmann, and Walter Lang
J. Sens. Sens. Syst., 10, 261–270, https://doi.org/10.5194/jsss-10-261-2021, https://doi.org/10.5194/jsss-10-261-2021, 2021
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The development of optical design is characterized by the desire for more applications and better performance. The latest result of this development is freeform optics offering almost unlimited possibilities for the designers. However, an optical component has also to be manufactured and tested by metrology. We propose a measurement technique for the surface characterization of freeform optical components and highlight the possible error sources and their influence on the measurement result.
Sebastian Schramm, Jannik Ebert, Johannes Rangel, Robert Schmoll, and Andreas Kroll
J. Sens. Sens. Syst., 10, 207–218, https://doi.org/10.5194/jsss-10-207-2021, https://doi.org/10.5194/jsss-10-207-2021, 2021
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During the geometric calibration of infrared cameras, the parameters that describe where object points are mapped onto thermal images are determined. The required reference data is obtained by capturing so-called calibration targets. In established approaches, it is difficult to estimate the lens distortions precisely. A newly developed target and its evaluation algorithm make it possible to increase the sensitivity of the calibration by finding reference points close to image borders.
Helmut Budzier and Gerald Gerlach
J. Sens. Sens. Syst., 10, 179–184, https://doi.org/10.5194/jsss-10-179-2021, https://doi.org/10.5194/jsss-10-179-2021, 2021
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In thermometry, the displayed temperature value of an object depends on the size of the object. This behaviour, the size-of-source effect, might be a major cause of measurement uncertainty in a thermoscene. The influence of diffraction and digitization can be described advantageously with the modulation transfer function. Especially with very small objects the displayed temperatures are too low. When imaging large objects, not only the edge areas are affected, but also the entire image.
Felix Lehner, Jürgen Roth, Oliver Hupe, Marc Kassubeck, Benedikt Bergmann, Petr Mánek, and Marcus Magnor
J. Sens. Sens. Syst., 10, 63–70, https://doi.org/10.5194/jsss-10-63-2021, https://doi.org/10.5194/jsss-10-63-2021, 2021
Thomas Strahl, Johannes Herbst, Eric Maier, Sven Rademacher, Christian Weber, Hans-Fridtjof Pernau, Armin Lambrecht, and Jürgen Wöllenstein
J. Sens. Sens. Syst., 10, 25–35, https://doi.org/10.5194/jsss-10-25-2021, https://doi.org/10.5194/jsss-10-25-2021, 2021
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For safety, environmental and economic reasons, methane leak detection is one of the most requested tasks for gas measurement devices. This paper compares the performance of a laser-based optical and acoustical detection scheme at different wavelengths and laser types, respectively. This forms a good basis for further developments of methane leak detection devices or can help to choose the right configuration for a certain methane leak detection application.
Sebastian König, Berndt Gutschwager, Richard Dieter Taubert, and Jörg Hollandt
J. Sens. Sens. Syst., 9, 425–442, https://doi.org/10.5194/jsss-9-425-2020, https://doi.org/10.5194/jsss-9-425-2020, 2020
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We present the metrological characterization and calibration of three different types of thermographic cameras for quantitative temperature measurement traceable to the International Temperature Scale (ITS-90). Relevant technical specifications are determined according to the requirements given in the series of Technical Directives VDI/VDE 5585. For the IETD and the NU, we also show how a significant improvement in the parameters can be achieved with the help of the data reference method.
Maximilian Wohlschläger and Martin Versen
J. Sens. Sens. Syst., 9, 337–343, https://doi.org/10.5194/jsss-9-337-2020, https://doi.org/10.5194/jsss-9-337-2020, 2020
Markus Stoehr, Gerald Gerlach, Thomas Härtling, and Stephan Schoenfelder
J. Sens. Sens. Syst., 9, 209–217, https://doi.org/10.5194/jsss-9-209-2020, https://doi.org/10.5194/jsss-9-209-2020, 2020
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Photoelasticity is considered a useful measurement tool for non-destructive and contactless determination of mechanical stresses or strains in the production of silicon wafers. In this work, a detailed derivation for the anisotropic stress-optic law is presented, and the corresponding stress-optical parameters are measured.
Ulrich Nordmeyer, Niels Neumann, Xiaozhou Wang, Dirk Plettemeier, Torsten Thiel, and Konstantin Kojucharow
J. Sens. Sens. Syst., 9, 199–208, https://doi.org/10.5194/jsss-9-199-2020, https://doi.org/10.5194/jsss-9-199-2020, 2020
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A completely new evaluation method for optical sensors is investigated in this paper. It originates from research that integrates optical sensors into radio-over-fibre networks. The laboratory-based experimental set-up is explained, and the findings are validated by a comparison to the conventional evaluation scheme. Finally, the work provides a detailed mathematical model to understand the implications of this new read-out method for practical applications.
Lakshan Tharmakularajah, Jakob Döring, and Karl-Ludwig Krieger
J. Sens. Sens. Syst., 9, 133–141, https://doi.org/10.5194/jsss-9-133-2020, https://doi.org/10.5194/jsss-9-133-2020, 2020
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In order to differentiate between a wet and a dry road surface, the water film height should be measured by using an infrared-based sensor system. By means of different wavelengths, it is also possible to distinguish between ice and water. In this article, a sensor system for the determination of the physical state of water on different surfaces using infrared LEDs and one photodiode is presented. This shall serve as a basis for the calculation of the road condition.
Mahmoud El-Safoury, Christian Weber, Olaf Kiesewetter, Yvonne Hespos, André Eberhardt, Katrin Schmitt, and Jürgen Wöllenstein
J. Sens. Sens. Syst., 9, 89–97, https://doi.org/10.5194/jsss-9-89-2020, https://doi.org/10.5194/jsss-9-89-2020, 2020
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The refrigerant R134a is classified as a greenhouse gas and was banned from use (in vehicles) by the European Union in 2017 due to its contribution to global warming. The more expensive alternative refrigerant R1234yf is considered an environmentally less harmful alternative owing to its significantly lower global warming potential. Our newly developed gas detector can detect both refrigerants separately and, thus, help prevent the use of illegal gas mixtures that contain both refrigerants.
Elena Kononogova, Albert Adibekyan, Christian Monte, and Jörg Hollandt
J. Sens. Sens. Syst., 8, 233–242, https://doi.org/10.5194/jsss-8-233-2019, https://doi.org/10.5194/jsss-8-233-2019, 2019
Tobias Pohl, Peter Meindl, Uwe Johannsen, Dieter Taubert, and Lutz Werner
J. Sens. Sens. Syst., 8, 195–205, https://doi.org/10.5194/jsss-8-195-2019, https://doi.org/10.5194/jsss-8-195-2019, 2019
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The Physikalisch-Technische Bundesanstalt (PTB) expanded its capabilities in the International System of Units (SI)-traceable absolute measurement of radiant power into the spectral range of the mid-infrared (MIR) by implementing additional MIR laser radiation sources at one of the PTB's cryogenic electrical substitution radiometer facilities. This extension enables absolute calibrations of the spectral responsivity of detectors in the MIR with low uncertainty.
Christian Niklas, Stephan Bauke, Fabian Müller, Kai Golibrzuch, Hainer Wackerbarth, and Georgios Ctistis
J. Sens. Sens. Syst., 8, 123–132, https://doi.org/10.5194/jsss-8-123-2019, https://doi.org/10.5194/jsss-8-123-2019, 2019
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We present in our paper two types of optical sensors that are capable of measuring the environmentally significant gases such as carbon oxide and dioxide as well as methane and water through absorption of light even in harsh environments of high temperature and pressure. Thus the sensors render it possible to measure inside combustion engines or in civilian fireplaces, which is necessary to meet the increasing demands of environmental protection regulations.
Stefan Oertel, Michael Eggert, Christian Gutsmuths, Paul Wilhelm, Harald Müller, and Helmut Többen
J. Sens. Sens. Syst., 8, 9–17, https://doi.org/10.5194/jsss-8-9-2019, https://doi.org/10.5194/jsss-8-9-2019, 2019
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Traceable wind velocity measurements with high resolution play a critical role in the field of wind energy. In this article we present a novel bistatic wind lidar system that has a high spatial and temporal resolution and a reduced measurement uncertainty compared to conventional systems as evidenced by comparison measurements. A first validation measurement in a wind tunnel with a laser Doppler anemometer as a flow velocity reference confirms the high accuracy of the bistatic lidar system.
Martin Weisbrich and Klaus Holschemacher
J. Sens. Sens. Syst., 7, 601–608, https://doi.org/10.5194/jsss-7-601-2018, https://doi.org/10.5194/jsss-7-601-2018, 2018
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The study describes how distributed optical strain measurement can be applied to steel surfaces. With the method presented, strain transfers from the substrate to the fiber core can be achieved that are almost identical to those of the reference measurement, especially with Ormocer® and polyimide coating.
The research results are to be used in the future for strain measurement in concrete construction on reinforcing steel.
Ruben Makris, Falk Hille, Marc Thiele, Dirk Kirschberger, and Damian Sowietzki
J. Sens. Sens. Syst., 7, 259–266, https://doi.org/10.5194/jsss-7-259-2018, https://doi.org/10.5194/jsss-7-259-2018, 2018
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In structural parts under vibrational loading fatigue cracks can initiate and grow, which can lead to structural failure. Conventional non-destructive testing methods for crack detection provide just a snapshot of fatigue crack evolution, whereas crack luminescence coating realizes clear visibility of the entire crack formation. Fatigue causing cyclic tensile tests and examinations on special test bodies allowing control of the crack opening width demonstrate a high sensitivity of the coating.
Markus Brüne, Wilhelm Furian, Wieland Hill, and Andreas Pflitsch
J. Sens. Sens. Syst., 7, 85–90, https://doi.org/10.5194/jsss-7-85-2018, https://doi.org/10.5194/jsss-7-85-2018, 2018
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The climate conditions in underground transportation facilities, especially the current airflow in terms of direction and speed, are the key factor driving smoke propagation in the case of a tunnel fire. Sensing this airflow is cost-intensive. Therefore, this paper focuses on gaining the information from temperature sensing along the tunnels using already installed optical fibers normally used for communications. This technique can replace thousands of temperature sensors.
Christoph Kroh, Roland Wuchrer, Margarita Günther, Thomas Härtling, and Gerald Gerlach
J. Sens. Sens. Syst., 7, 51–55, https://doi.org/10.5194/jsss-7-51-2018, https://doi.org/10.5194/jsss-7-51-2018, 2018
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The inline monitoring of parameters in aqueous liquids is facing an increasing demand in many application areas. In this paper we report on an optical monitoring of the pH value in liquids by means of a sensitive hydrogel, which can be applied in the physiological range. Our results indicate a nearly linear dependency between pH value and hydrogel swelling. Furthermore, we show an improvement of the response time by a factor of 2 in comparison to other systems exploiting this kind of hydrogel.
Beate Oswald-Tranta
J. Sens. Sens. Syst., 7, 13–20, https://doi.org/10.5194/jsss-7-13-2018, https://doi.org/10.5194/jsss-7-13-2018, 2018
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Images of an infrared camera show blurring effects while recording a moving object. Not only the contrast is corrupted by the motion but also the object temperature seems to be lower. It is shown how such images and the true temperature with a good approximation can be restored. Since the detection mechanism of an infrared camera is different from usual digital cameras, also the restoration is different. Examples are presented for motion deblurring used to restore images with different motions.
Roberto Marsili and Gianluca Rossi
J. Sens. Sens. Syst., 6, 361–365, https://doi.org/10.5194/jsss-6-361-2017, https://doi.org/10.5194/jsss-6-361-2017, 2017
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The car production industry is being subjected to more and more pressing technological challenges. In this framework the use of an advanced measurement technique such as thermoelasticity allows the engineers to have a fast and reliable tool for experimental investigation, optimization and validation of the FEM models. In this work it is shown how the thermoelastic measurement technique can be used to optimize a Ferrari car frame.
Henrik Zimmermann, Mathias Wiese, Luigi Fiorani, and Alessandro Ragnoni
J. Sens. Sens. Syst., 6, 155–161, https://doi.org/10.5194/jsss-6-155-2017, https://doi.org/10.5194/jsss-6-155-2017, 2017
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Because of their direct impact on patients, medical supply lines are under strict regulations and have to be monitored in terms of purity on a regular basis. State-of-the-art measurement solutions do not allow for continuous bedside monitoring. The aim of the presented work is to provide a compact multispecies monitoring system based on the latest quantum cascade laser technologies allowing for the continuous bedside monitoring of medical gases.
T. Ott, M. Schossig, V. Norkus, and G. Gerlach
J. Sens. Sens. Syst., 4, 313–319, https://doi.org/10.5194/jsss-4-313-2015, https://doi.org/10.5194/jsss-4-313-2015, 2015
M. Mohebbi
J. Sens. Sens. Syst., 4, 209–215, https://doi.org/10.5194/jsss-4-209-2015, https://doi.org/10.5194/jsss-4-209-2015, 2015
F. Vita, C. Kern, and S. Inguaggiato
J. Sens. Sens. Syst., 3, 355–367, https://doi.org/10.5194/jsss-3-355-2014, https://doi.org/10.5194/jsss-3-355-2014, 2014
U. Kienitz
J. Sens. Sens. Syst., 3, 265–271, https://doi.org/10.5194/jsss-3-265-2014, https://doi.org/10.5194/jsss-3-265-2014, 2014
T. Bley, E. Pignanelli, and A. Schütze
J. Sens. Sens. Syst., 3, 121–132, https://doi.org/10.5194/jsss-3-121-2014, https://doi.org/10.5194/jsss-3-121-2014, 2014
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Short summary
This work presents a cost-effective optical-based sensor for pH monitoring of sample volumes less than 150 µL. As part of a bigger project to develop a stand-alone micro bioreactor system, measurements carried out with phenol red and DMEM reported a standard error of calibration in the physiologic pH range (6.5–7.5) of pH ±0.04. Compared to other accessible optical-based sensors this reported system is a good alternative regarding the overall costs of less than EUR 50.
This work presents a cost-effective optical-based sensor for pH monitoring of sample volumes...
Special issue