Adaptation luminance variation under lamps of different spectral compositions with variable surrounding luminance effects

Abstract

The mesopic photometry system is expected to enable lighting designers to provide more visually effective lighting designs for appropriate outdoor lighting applications which are supposed to be more energy efficient compared to the photopic system. Studies on the adaptation characteristics are performed to define adaptation luminance and viewing conditions on the basis of peripheral adaptation state of observers for implementation of mesopic photometry system in outdoor lighting. In this work, experimentation is carried out to study the change in adaptation luminance due to various combinations of lamps with different spectral compositions and variable surrounding luminance effects caused by warm white and cool white light sources. The analysis of experimental results reveals that adaptation luminance can be considered instead of mesopic luminance for fixed area of measurement. Spectral composition of surrounding light sources imparts significant contribution on adaptation luminance. Cool white LED lamp shows most effective adaptation luminance under cool white surrounding lighting effect.