Abstract Surface metrology is of key importance for applications in a wide range of fields, such as, aeronautics, automotive, the semiconductor industry, tribology and healthcare to name only a few of the most relevant. The use of calibrated physical standards is imperative to guarantee the reliability of the results obtained in industry and laboratories using different measurement instruments and techniques, such as contact stylus profilometers, coherence scanning microscopes, confocal microscopes and focus variation microscopes. Most of them use step height or depth setting standards for the calibration in the Z -axis. Accordingly, work has been performed at the Spanish Centre of Metrology (CEM) to provide traceability for the first time at a national metrology institute, using the combination of a SIOS metrological nanomeasuring machine (NMM) with a laser focus sensor for extended range (LFS-e). This paper focuses on measurements with this system on the Z -axis, which is the coordinate with the most stringent requirements for these techniques. This primary instrument with direct traceability to the metre realisation has proven to be a reliable tool for the calibration of a wide variety of groove and step height standards. The combination NMM + LFS-e is able to calibrate these physical standards within a range of up to 5 mm. Measurement results of step height/groove standards ranging from 9 nm to 900 µm obtained using this system are presented. These calibrated standards provide traceability to other surface measurement techniques in CEM’s Micro and Nanodimensional Metrology Laboratory. The reliability of this traceability route is demonstrated through the results obtained in the International Bureau of Weights and Measures’ (BIPM) international comparisons of surface material standards calibrations, using NMM + LFS-e system and contact stylus profilometry techniques. These results demonstrate a robust traceability route validated at the highest international level.
The Spanish National Metrology Institute (CEM) has developed a primary magnetic laboratory that requires continuous updates to meet the evolving industry needs. This paper outlines the traceability chain of CEM's magnetism laboratory, which begins with a Nuclear Magnetic Resonance (NMR) sensor capable of measuring from 40 mT to 1.5 T using multiple probes. The secondary standards used in the lab are detailed, ensuring high precision and reliability in magnetic measurements.
Core body temperature measurement is a key indicator of human health. However, its measurement, although very widely performed, is also often unreliable, especially through infra-red methods. This unreliability can lead to incorrect clinical diagnoses, treatment pathways and decisions about infection status, as, for example, during the recent Covid-19 pandemic. Here we give an outline of the issue and describe work undertaken by the CCT Task Group for Body Temperature Measurement to improve this situation. This has been through initiating a key comparison of body temperature calibrators, developing best practice for body temperature measurement by ear and forehead thermometers and thermal imaging and increasing engagement between metrology and clinical thermometer standards communities.
This paper describes the collaborative project between National Research Council of Canada (NRC) and Centro Español de Metrología (CEM) for the construction and comparison of high temperature fixed points (HTFPs). A hybrid-type crucible that uses the piston method for filling has been jointly developed. A series of 12 high temperature fixed point blackbodies (HTFPBBs) have been constructed, including Cu, Ru-C, Ir-C, Re-C and WC-C covering the temperature range from 1084°C to 2750°C. All these cells were filled in NRC facilities by CEM and NRC staff. Two cells of each type of fixed point were constructed (except for the WC-C cells), using crucibles from two different suppliers in order to study the influence of the density and emissivity of the crucible in the HTFPs’ performance. Moreover, four WC-C cells were made using tungsten powder from two different suppliers, covering all the possible combinations of tungsten powder and crucibles acquired for this project. All cells, and additionally a Pt-C HTFPBB belonging to NRC, have been measured firstly at NRC and, afterwards, at CEM. Both laboratories have calculated the ITS-90 temperatures from their respective measurements and the results have been compared. Differences on the ITS-90 temperatures of the HTFPBBs measured at each lab are within uncertainties of the comparison. After the comparison, CEM kept one Cu cell, one Ru-C cell, one Re-C cell and two WC-C cells. The rest of the fixed points involved in the comparison were sent back to NRC.
Quantum-based methods have the potential to become primary standards for the SI unit of pressure, the pascal.Some of these standards are based on the determination of the refractive index of a gas under different pressure conditions by Fabry-Perot (FP)based refractrometry methods.These methods depend on the control of other quantities, mainly the temperature and the mechanical stability.Ideally, the use of an improved cavity with piezo-electric and elasto-optic characteristics will allow for a novel and improved control of the effects of these parameters.
