Does pedestrian useful visual field change at night?

This paper reports an investigation into the shape and size of the useful visual field over which pedestrian visual gaze tends to fall during day and night and discusses the factors affecting useful visual field and the function of peripheral vision. A previous study by authors explored what people look at at night in the streets employing an eye tracking methodology. This study is secondary analysis of the data captured by the previous study. The study shows that street lighting affects and reduces useful visual field of pedestrians and provides guidelines to more effective distribution of light at night based on the optimum pedestrian useful field of view. Our finding emphasises the importance of illuminance on vertical surfaces and hence the for it to be considered when designing light for our streets.