Travel Speed and Visibility in a Pedestrian Space with Inhomogeneous Distribution of Floor Illuminance

The purpose of this paper is to reveal the relationship between illuminance distributions of floor surface and travel speed and visibility. Subjective experiments were examined with a real-scale space, which is 25 m length by 1.8 m width by 1.8 m height. We set three kinds of installation intervals of lighting planes through five levels of average illuminance on the floor surface in order to set various inhomogeneous conditions. Five subjects participate in this experiment, who have good visual acuity more than 1.2. Their visual acuity is measured with Landolt ring (800 cd/m2 and contrast 0.9).