A review of methods for measuring the reflectance and transmittance of lighting materials

Abstract

CIE Committee E-2.2 has prepared a report dealing with the characteristics of lighting materials and their measurement. In this paper the authors review methods which have been proposed from time to time for measuring transmittance and reflectance in their different modes and for both directional and diffuse illumination. It is concluded that it is preferable to base these measurements on the use of an integrating sphere, and suitable designs of apparatus and arrangements for determining the more important photometric quantities are described. It is emphasized, however, that these methods are not the only sound methods for making the measurements.