When a person (P) existing ahead of a vehicle is detected based on an image captured by a camera (18) configured to capture ahead of the vehicle, illumination regions (Aa to Ad) are moved in a right and left direction so as to include the person (P). Also, non-illumination regions (Aa and Ab) are formed in the illumination regions so that the non-illumination regions include at least a head (Ph) of the person (P).