STUDY ON VISUAL PERCEPTION OF FLICKER FROM LOW-HEIGHT MOUNTED LED LUMINAIRE FOR ROAD LIGHTING

Taking the advantage of small size, long lifetime and high reliability, LEDs enable new innovative lighting solutions for both indoor and outdoor application. A new method to lit-up roads, namely by means of LED luminaires mounted at a height of around 1 meter above the road surface, is recently introduced to the market. Since the luminaires emit light on the side of vehicles, a scrolling light is perceived by their users while driving along the road. The resulting luminance fluctuation hereafter referred to as flicker - may affect the comfort of the driver, and thus, traffic safety in general. Therefore, a perception study is carried out in the laboratory to investigate how flicker from lateral illumination affects people's comfort. As expected, the study results show a significant impact of flicker frequency. As a consequence, luminaire spacing of low-height mounted road lighting luminaires should be carefully selected to avoid driver's discomfort.