PERCEIVED BRIGHTNESS OF COLORED LIGHT : A study about the perceived brightness of near-monochromatic light in comparison to neutral white light

Abstract: Recently, there has been a notable rise in the use of colored lighting for both indoor andoutdoor spaces. This trend necessitates a clear understanding of the principles behindselecting lighting levels that are both ergonomic and energy efficient. The objective ofthis study was to establish guidelines for planning colored light. An experiment wasconducted where the perceived brightness of three different near-monochromatic lightswere compared to white light. The stimuli covered a narrow visual field. 33 personsaged 18-40Y participated. Through the measurement of the participants' perception ofthe amount of colored light required -to achieve the same level of brightness as withwhite light- the study was able to determine a percentage-based relationship betweencolored and white light. The result showed that there were clear differences in theperceived brightness of the different colored lights, in line with earlier research withsimilar conditions. This implicates that the results may be used as a foundation whenplanning colored light.