Testing sparkle measurements capabilities of national metrology institutes.

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 important for automotive, cosmetic or displays industries, a measurement scale need to be developed, so that traceability can be provided by national metrology institutes (NMI) or designated institutes. Some of them (PTB, METAS, CMI and CSIC) have defined the measurands for sparkle and have developed a photometric and image-based methodology to measure them. The specific objective of this research work is to test the existing capabilities of these NMIs to measure sparkle.

Ferrero, A.; Instituto de Óptica, Consejo Superior de Investigaciones Científicas, Madrid, SPAIN
Basic, N.; METAS, Bern, SWITZERLAND
Campos, J.; Instituto de Óptica, Consejo Superior de Investigaciones Científicas, Madrid, SPAIN
Pastuschek, Marcel; 4.5, Angewandte Radiometrie, PTB-Braunschweig
Perales, E.; Universidad de Alicante, Alicante, SPAIN
Porrovecchio, G.; CMI, Prague, CZECH REPUBLIC
Smid, M.; CMI, Prague, CZECH REPUBLIC
Schirmacher, Alfred; 4.5, Angewandte Radiometrie, PTB-Braunschweig
Velazquez, J. L.; Instituto de Óptica, Consejo Superior de Investigaciones Científicas, Madrid, SPAIN
Martinez-Verdu, F. M.; Universidad de Alicante, Alicante, SPAIN