Comparison of LED Luminaires for Roadway Lighting Using Object Detection and Color Recognition Distances
This study compared two LED luminaires and their abilities to provide detection distance and color recognition distance of potential roadway hazards. Detection distance is regarded as a metric of visibility. Color recognition distance is a metric for comparing the impact of the CCT (Correlated Color Temperature) of each luminaire and their color contrast impact. Mesopic vision, the mode of vision most commonly used for night driving, was considered in this study. The impacts of luminance and color contrast were addressed in this study. The experiment was performed on the Virginia Smart Road where small wooden targets of different colors and pedestrians wearing different colors were detected by drivers of a moving vehicle in a controlled environment. The key difference between the two luminaires was their color temperatures (3500K versus 6000K) The results indicated that neither light source provided a significant benefit over the other although significant interactions were found among object color, age, and lighting level. The results indicate that the luminaires provide similar luminance contrast but their color contrasts depend heavily on the color temperature, the object, and the observer.