Illuminance from luminance measurement experimental results

The ability of multi luminance meters in identifying the directionality of light sources and their possibility in selecting and analysing the contribution to luminance of sources located in different places, makes the Photometric Laboratory of the University of Padova to use them to measure illuminance in critical cases, like in glare quantification and measuring of reflection properties of surfaces. After a description of the method and the presentation of some specific applications, measurement results are presented, showing the efficacy of the proposed method by comparing measurement obtained by illuminance meters and by the use of a multi luminance meter.