The Technical Committee on "Optical Properties of Glass" of the International Commission on Glass (ICG-TC10) organised Round Robins on normal incidence transmittance & reflectance measurements on translucent glass panes in the solar range using commercial spectrophotometers equipped with integrating sphere accessories. The samples were sand-blasted glass panes & glass laminates with translucent plastic films representative of the current production. The measures of visible & solar parameters were then obtained from the recorded spectral curves following the procedures established by the European standard EN410. The recorded curves &, consequently, the integrated values showed large discrepancies & underestimated the parameters due to the inappropriate geometry of the small integrating spheres used in commercial spectrometers.
