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Within the framework of the EURAMET project 1242 ‘Measurement of areal roughness by optical microscopes’, coordinated by PTB, comparative measurements of areal roughness with different optical microscopes were carried out for the first time at 6 national metrology institutes. The comparison results revealed a large deviation up to 60 % from the reference roughness parameters, depending on the...

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The novel picoindenter from PTB, which uses the tip of an atomic force microscope (AFM) as an indenter to characterize nanomaterials dimensionally and mechanically, has now been decisively extended: In the "Laboratory for Emerging Nanometrology" (LENA) at TU-BS, pyramid-like Berkovich tips were produced on AFM cantilevers using a focused ion beam (FIB). These tips can also be used in the...

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The eccentric nanoindentation of silicon micropillars has been investigated. It could be shown that 10 % deviation of the measured indentation modulus occurs when the location of indentation is deviating by up to 40 % of the radius of the pillar from the pillar’s centre. During these measurements the measured indentation hardness remains almost constant, while the measured indentation modulus...

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A novel 3D measuring method based on scanning electron microscopy and the "shape from shading" reconstruction approach was tested to characterize the shape of silicon-microprobe-tips. It could be shown that there is an optimal working distance, that tilting of up to 2 ° is tolerable, that the rotation of the sample is not critical for flat samples, but that there are edge deviations in the image...

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High-speed roughness measurements with piezoresistive silicon microprobes require good dynamic properties of the probe. For this purpose, tip flight tests were carried out with these microprobes on rectangular structures, in which the flight distance of the microprobe tips in the rectangular grooves was measured as a function of the probing force and the traverse speed. For the investigated...

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In June 2020 the EMPIR network project "Support for a European Metrology Network on Advanced Manufacturing" was started. This project targets at the strengthening of European manufacturing industry through innovative metrology. For the first time, a coordination at the European level will be realised, which enables an infrastructure for sharing of metrological knowledge. Moreover, a research...

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“Structure from Motion” is a photogrammetric technique for capturing three-dimensional objects, that is well suited for the contactless measurement of roundwood on vehicles. In cooperation with Dralle A/S (Hørsholm/Denmark), the Physikalisch-Technische Bundesanstalt (PTB) has evaluated the metrological performance of a system newly developed for the measurement of roundwood stacks on vehicles. The...

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Often, beams from multiple light sources have to be spatially superposed for sensor systems so that they propagate along the same direction. Waveguide architectures for beams that are vastly spectrally separated were compared to each other in a systematic study. The results can be used for the development of novel standards in length metrology with reduced measurement uncertainties.

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Fourier transform infrared (FTIR) spectroscopy is a powerful technique in analytical chemistry. Typically, spatially distributed spectra of the substance of interest are registered simultaneously using FTIR spectrometers equipped with array detectors. Scanning methods such as near-field FTIR spectroscopy are a promising alternative providing higher...

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Annular subaperture stitching interferometry (ASSI) is a common approach for the measurement of aspherical surfaces. A common obstacle of ASSI is the occurrence of lateral displacement errors when the sensor or specimen is repositioned between the subaperture measurements. Our contribution focuses on modeling of the statistical displacement errors. Avirtual experiment is presented simulating the...

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The challenges faced in a comparison of measuring the detection efficiency of free-running InGaAs/InP single-photon avalanche detectors (InGaAs/InP SPAD) were studied by four European National Metrology Institutes (NMIs) meeting at a single laboratory. The main purpose of this study is to develop a trustable measurement technique and to provide a snapshot of the methods used by the four NMIs for...

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Der erste internationale Vergleich in der ultraschnellen elektrischen Wellenformmetrologie konnte erfolgreich abgeschlossen werden. Dazu wurde die Zeit- und Frequenzantwort einer Photodiode mit einer nominellen Bandbreite von 100 GHz an vier Metrologieinstituten gemessen und miteinander verglichen. Generell wurde eine gute Übereinstimmung zwischen den unterschiedlichen Ergebnissen erreicht. Jedoch...

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Verifizierung der Kalibriermethode durch eine Dreiecksmessung

Seit mehr als 20 Jahren basiert die Rückführung von Hochohmwiderständen in der PTB auf der Kalibrierung von 1-MΩ-Widerständen mittels Kryostromkomparator. Durch den Einsatz eines neuen Kryostromkomparators mit höheren Windungszahlen und verbessertem Rauschverhalten ist es jetzt auch möglich, Widerstände bis 10 MΩ zu kalibrieren. Die Kalibrierunsicherheit verbessert sich dabei um einen Faktor fünf...

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Kalibrierteiler KT34 für die Brückennormal-Kalibrierung

Für die Kalibrierung von Brückennormalen für die Dehnungsmessstreifen-Messtechnik wurde ein neuer Kalibrierteiler für den Nennwertbereich von 20 mV/V bis 100 mV/V entwickelt. Dieser ermöglicht eine stabilere und zeitsparende Kalibrierung bei Handmessungen sowie die Verwendung des vollautomatisierten Brückennormal-Messplatzes der PTB. Für diesen Zweck wurde die Messplatz-Software erweitert und in...

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Dynamic PIM measurement being carried out on a multiband antenna

Passive intermodulation (PIM) leads to interference signals in cellular networks and can therefore degrade network quality. In the project “5G-Reallabor”, PTB is working on traceability for PIM measurements in a laboratory environment with the aim of characterizing and reducing the measurement uncertainties and, thus, of contributing to the reliable function of the cellular network.

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