Applying the Unified Glare Rating for a non-uniform residential luminaire

The Unified Glare Rating (UGR) and the modified version (UGR’) have been developed for a luminaire in a typical indoor environment. In this paper, the application of these metrics is explored for an outdoor residential luminaire with a non-uniform spatial luminance distribution. The luminaire was characterized in a large near field goniometer (NFG) and luminance images were created at four angles specified in the CIE 232:2019 document. Some practical issues of applying the UGR’ for a non-uniform residential luminaire are discussed, such as selecting the luminous area, the blurring parameter and the background luminance.