IES Transaction: Streetlighting Luminaire Distributions for Uniform Luminance and Illumination

Abstract

This paper explores the differences and similarities of luminaire distributions that would produce optimum uniformity of horizontal illumination, pavement luminance, and vertical illumination. This is done by calculating the required candlepower at various angles to produce the three idealized results. The resulting candela distributions are then plotted and analyzed with regard to their ability to produce the contrast levels required for visibility at various vehicular speeds in accordance with the visibility metric. A unique new method of plotting the visibility or contrast results of an installed streetlighting system in terms of the area of roadway over which such results are achieved is disclosed and illustrated.