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Working Group 4.11


The working group “Spectroradiometry” is responsible for the realisation, maintenance and dissemination of the spectral irradiance unit in the spectral range from 200 nm to 2500 nm. One focus of research and development lies on radiometry for high UV-irradiances as well as development of new transfer standards and calibration procedures for the dissemination of radiometric units to customers from industry and research. Moreover, the working group carries out also research and development in the field of new characterisation, correction and calibration procedures for the spectroradiometry based on compact array spectroradiometers. Members of the group also make contributions to relevant committees in national and international standardisation bodies and metrology organisations (Opens external link in new windowDIN, Opens external link in new windowCIE, Opens external link in new windowEURAMET-TCPR, Opens external link in new windowCCPR).



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Research and development related to primary realisation methods of the spectral irradiance unit

Development of appropriate transfer standards and adequate calibration procedures at high UV-irradiance levels for the purpose of providing unbroken traceability chains to the SI for measurements in various industrial applications

Development of characterisation, correction and calibration procedures for spectrally resolving measurement instruments based on new technologies, such as CCD-array spectroradiometers

Current projects

EURAMET: EMRP ENV 59 „Traceability for atmospheric total column ozone” (Opens external link in new windowhttp://projects.pmodwrc.ch/atmoz/index.php/)

EURAMET: EMRP SIB 57 „New primary standards and traceability for radiometry” (Opens external link in new windowhttp://www.inrim.it/Newstar/index.html)

EURAMET: Project 1106 „Traceability of the spectral solar UV irradiance scale to SI units”

EURAMET: Project 1103 „Euramet.PR-K1.a Key Comparison of Spectral Irradiance”

EURAMET: Project 443 „Comparison of Ultraviolet Power Meters”

EURAMET: Project 36 „UV radiometric scales and calibration services”

BMWi: MNPQ 04/13 (mit sglux SolGel Technologies GmbH) „Schaffung neuer industrienaher Kalibrierdienstleistungen für radiometrische Messgrößen im Bereich hoher UV-Bestrahlungsstärken“

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  • Calibration of sources in terms of spectral irradiance in the wavelength range from 200 nm to 2500 nm
  • Calibration of UVA radiometers at 365 nm
  • Determination of array spectroradiometer properties by using spectrally tuneable lasers

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The national standard for spectral irradiance

The unit for the spectral irradiance is realized by a high-temperature blackbody radiator BB3200pg within the wavelength range between 250 nm and 2500 nm.


Measurement setup for the calibration of lamps

The transfer of the unit for the spectral irradiance is carried out via calibration of transfer lamps.

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