Abstract
Artificial Light at Night (ALAN) play an important role in people’s sense of safety and security when they move around outdoors by foot, by car, or on a bike. Light is important for providing pure visibility of obstacles, other pedestrians, and possible threats. But lighting characteristics also influence qualitatively how objects, people and the environment appear. The perception of facial expressions can contribute to the sense of social security at night. Here we study whether lighting characteristics influence perceived facial expressions, specifically friendliness. We study how lighting directions affect the perception of friendliness on styrofoam heads. First, 10 pictures of styrofoam heads under systematically varied light directions were evaluated in a rating experiment. Second, the styrofoam heads will be taken outdoor on two pedestrian roads with light poles 4.5 meters high and bollards 0.65 meters high. The heads will be positioned at various distances from the poles and bollards, to systematically vary the light direction. Participants will rate the perceived friendliness of styrofoam heads’ faces. Additionally, cubic light measurements will be done to characterise the lighting. Results of experiment 1 show that the direction of the lighting systematically influenced how friendly a face looked. Results so far indicate that if the eyes are in shadow, faces looked more unfriendly. The results suggest that light diffuseness also has an impact on the perception of friendliness. Our findings indicate that optimising lighting technique and optical equipment of streets luminaires for pedestrian roads, revealing larger parts of pedestrians' faces and avoiding hard shadows, can positively influence the sense of social security after dark.