Reflectance changes in white reflectance standards measured in different instruments with 0/d geometry

摘要

This work presents a comparison of reflectance measurements of different white reflectance standards, measured with three different spectro photo meters which include an integrating sphere accessory. The goodness of a procedure described elsewhere for the correct inclusion and exclusion of specular component of reflectance has been tested. Results obtained for the specular included geometry seem to probe the adopted procedure. Significant differences, not only for different angles of incidence but for the different sphere diameters, remain after correction for the specular excluded geometry. To investigate these differences, angular distribution of reflectance and its dependence with wavelength has been studied for two angles of incidence.