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Bidirectional reflectance scale comparison between NIST and PTB



Catherine C. Cooksey, Maria E. Nadal, David W. Allen, Kai-Olaf Hauer, Andreas Hoepe


A comparison of bidirectional reflectance scales between the National Institute of Standards and Technology (NIST) and the Physikalisch-Technische Bundesanstalt (PTB) has been performed. Measurements of two sets of white diffuse reflectance standards, two sintered polytetrafluoroethylene (PTFE) samples and two matte ceramic samples, were acquired using the 0:45 geometry where the angle of irradiation was 0 and the angle of reflection was 45. The results of this comparison show excellent agreement within the combined uncertainties.


Cooksey, C. , Nadal, M. , Allen, D. , Hauer, K. and Hoepe, A. (2015), Bidirectional reflectance scale comparison between NIST and PTB, Metrologia, [online], (Accessed April 15, 2024)
Created May 1, 2015, Updated November 10, 2018