Michael Matus

On estimation of distribution temperature

Distribution temperature is a concept that assigns a temperature to radiation from an incandescent lamp, which has a relative spectral power distribution reasonably close to that of a blackbody radiator. Different least square estimation methods for determination of distribution temperature are compared. Their applicability is discussed with regard to uncertainties of the spectral irradiance data of incandescent lamps. Simulation results are analysed to support theoretical conclusions. Experimental results indicate that the estimation method currently recommended by CIE will lead to feasible results only if the relative uncertainties of spectral irradiance data over the chosen wavelength region can be presumed constant. Otherwise, the use of this estimation method weighted with the relative uncertainties is suggested.

Final report for the period 2007–2009 on the CCL-K11 ongoing key comparison

Lasers from nine national metrology institutes (NMIs) were compared as part of the CCL-K11 ongoing key comparison, initiated by the 13th meeting of the Comite Consultative des Longeurs (CCL) in 2007. The absolute frequency of the f component of the R(127) 11–5 transition of molecular iodine was measured for these lasers following the technical protocol for CCL-K11. The results of these measurements are compiled in the present report. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCL, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

Calibration of surface roughness standards: Key Comparison EURAMET.L-K8.2013

The key comparison EURAMET.L-K8.2009 on roughness was carried out in the framework of a EURAMET project starting in 2009 and ending in 2011. It involved the participation of 14 National Metrology Institutes from Europe, North America, Central America, South America and Africa representing three regional metrology organisations. Four surface texture standards of different type were circulated and on each of the standards several roughness parameters according to the standard ISO 4287 had to be determined. 27 out of 171 individual results were not consistent with the reference value. After some corrective actions the number of inconsistent results could be reduced to 24, which correspond to about 14% of the total. In addition to the material standards, two soft-gauges were circulated, which allow to test the software of the instruments used in the comparison. The comparison results help to support the calibraton and measurement capabilities (CMCs) of the laboratories involved in the CIPM MRA. == Main text To reach the main text of this paper, click on Final Report [http://www.bipm.org/utils/common/pdf/final_reports/L/K8/EURAMET.L-K8.PDF] . Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/ [http://kcdb.bipm.org/] . The final report has been peer-reviewed and approved for publication by the CCL, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Final report on inter-RMO Key Comparison EUROMET.L-K5.2004: Calibration of a step gauge

The results of the inter-RMO key comparison EUROMET.L-K5.2004 on the calibration of a step gauge are reported. Eighteen National Metrology Institutes and one Designated Institute from four different metrological regions all over the world participated in this comparison which lasted three years, from December 2004 to December 2007. A lack of stability was observed through the shifting of some of the inserted gauges. In order to save the comparison and get valuable and useful conclusions, it was agreed to exclude four gauges from calculation and assume that only seven gauges were reasonably stable so as to get the corresponding reference values. It was also agreed to divide the participants into two groups, analyze separately their results and, taking the pilot as the linking laboratory, refer the results to common reference values. The inverse-variance weighted mean was taken as reference value. Due to the significant instability of the step it was also considered an artefact uncertainty. The reported uncertainties ranged from 0.045 ?m to 1.2 ?m (k = 1). The uncertainty of the artefact ranged from 0.018 ?m (for the 20 mm face) to 0.176 ?m (for the 400 mm face). The compatibility of all participants for measuring step gauges was demonstrated with the only exception of a participant showing very high systematic (both positive and negative) errors. Five participants communicated higher uncertainties than the corresponding approved CMCs. A set of Recommendations and Actions were agreed therefore. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCL, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).