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In Kooperation mit dem Helmholtz-Zentrum Berlin (HZB) und der Tsinghua-Universität Peking wurde an der Metrology Light Source (MLS), dem Elektronenspeicherring der Physikalisch-Technischen Bundesanstalt in Berlin, der Machbarkeitsnachweis für die erste Stufe des sogenannten „Steady State Micro Bunching“ (SSMB) erfolgreich erbracht. Es konnte damit erstmals an einem Speicherring gezeigt werden,...

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Spectral responsivity (SR) measurements are a powerful technique to measure the opto-electronic properties of photovoltaic devices like solar cells or PV modules. Although the SR determination of solar cells is a common and established technique for many years, much more effort must be taken to determine the SR of PV modules due to their size. Significantly larger and more complex solar simulator...

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Solar simulators for PV modules often consist of several lamps arranged side by side to provide the irradiance necessary for PV module testing under standard test conditions. Since these simulators are no point sources, the angular distribution of the radiance emitted by the simulators can lead to systematic deviations in measured PV device’s performances. To quantify the opening angle of a solar...

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Im Rahmen des von der PTB koordinierten EMPIR Projektes PRISM-eBT, Primary standards and traceable measurement methods for X-ray emitting electronic brachytherapy devices, wird ein Primärnormal auf der Basis einer Extrapolationskammer entwickelt. Es wurden erste Simulationsrechnungen zur Bestimmung optimaler Materialien durchgeführt, daraufhin wird zurzeit das Primärnormal konstruiert und im...

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Am LENA, in Kooperation mit der TUBS und der PTB, werden nanostrukturierte GMR-Mikrofarbfilter designt, entwickelt und gefertigt. In Kombination mit CCD oder CMOS Bildsensoren sollen damit effiziente spektroskopische Sensoren für Anwendungen in Medizin und Biologie entwickelt werden. Die GMR-Farbfilter basieren auf periodischen Subwellenlängen-Metallgittern in Kombination mit einer dielektrischen...

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We show a novel method to derive best-fitting sample parameters and their uncertainties from measured Mueller matrices.
The nonoptimal treatment of depolarization in current approaches to evaluate Mueller matrix measurements may lead to systematic measurement errors and inadequate uncertainty estimations, particularly for surfaces with substantial depolarization. To overcome these issues, we...

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Spectroscopic Mueller matrix ellipsometry is a promising tool for the characterization of nanostruc-tured surfaces. Direct optical measurements of samples with geometrical dimensions smaller than the incident wavelength are inherently limited by the classical resolution limit. However, as an indi-rect measurement technique, this limit does not apply to ellipsometry. In this contribution, we...

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The range of possible implementations of single-photon sources in quantum information processing is rapidly growing. In order to achieve high accuracy and metrological traceability, we need reliable methods for their absolute characterization. Furthermore, single-photon emitters could be implemented as a standard source for the detection efficiency calibration of single-photon...

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Die Definition des Ampere, Einheit der elektrischen Stromstärke, basiert im jüngst revidierten Internationalen Einheitensystem (SI) auf einem festgelegten Wert für die Elementarladung e. Das Joint Research Project (JRP) „e-SI-Amp: quantum realisation of the SI ampere“ wurde im Rahmen des europäischen Metrologieforschungsprogramms EMPIR ins Leben gerufen, um entsprechende Methoden zur Erzeugung und...

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Two-way satellite time and frequency transfer (TWSTFT) is a primary technique for the generation of coordinated universal time (UTC). At present, more than 12 timing laboratories around the world use SAtellite Time and Ranging Equipment (SATRE) modems in TWSTFT operations and contribute data for the realization of UTC. The advantages of TWSTFT are its small calibration uncertainty (≤1.0 ns if the...

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Single-photon sources are set to be a fundamental tool for metrological applications as well as for quantum information related technologies. Because of their upcoming widespread dissemination, the need for their characterization and standardization is becoming of the utmost importance. Here, we illustrate a strategy to provide a quantitative estimate of the multi-photon component of a...

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Bericht über den Stand der pränormativen Aktivitäten in CIE JTC 12 "The measurement of sparkle and graininess" und über neuartige definierte Proben zur Charakterisierung von Messapparaturen und -verfahren.

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We present the concept of a new setup, which combines two different sampling methods to measure the modulation transfer function of camera objectives. The development process with the goal of reaching a measurement uncertainty of 0.01 (k=2) is supported by optical ray tracing simulations in addition to the geometrical modeling of the system.

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Die AG 4.51 Reflexion und Transmission (https://www.ptb.de/cms/ptb/fachabteilungen/abt4/fb-45/ag-451.html) des Fachbereichs 4.5 Angewandte Radiometrie der PTB Braunschweig betreibt im Arbeitsbereich der gerichteten Reflexions- und Transmissionsmessungen eine Referenzapparatur, die einen nominellen Wellenlängenbereich von 200 nm bis maximal 20 m abdeckt. Zur Erzeugung der Messtrahlung oberhalb von...

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Diffuse reflectance measurements in sphere geometries are usually performed using a single photodetector. However measurements of graininess require also spatial resolution, thus they are performed using a radiometric camera attached to the integrating sphere. The usually applied measurement geometry is d:0°. When performing such measurements on glossy samples, the phenomenon of gloss exclusion...

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Sparkle, as defined by ASTM E284 -17 Standard Terminology of Appearance is "the aspect of the appearance of a material that seems to emit or reveal tiny bright points of light that are strikingly brighter than their immediate surround and are made more apparent when a minimum of one of the contributors (observer, specimen, light source) is moved". Since the measurement of this visual texture is...

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The Supplementary Comparison COOMET.PR-S2 was carried out to ensure the correctness and comparability of angle of rotation of plane of polarization measured by the Participants of the comparison within the uncertainties claimed for their measuring facility.
COOMET.PR-S2 was conducted within the Regional Metrology Organization (RMO) "Euro-Asian Cooperation of National Metrological Institutions"...

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Single-photon sources play an important role in several fields of research, e.g. in quantum key distribution and quantum-enhanced measurements. In radiometry, a single-photon source is very favorable, compared to a classical source, as a standard source for the detection efficiency calibration of single-photon detectors. Furthermore, such source is necessary to close the gap between classical and...

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