A light guide plate presents a plurality of patterns via prisms illuminated by light sources aligned along one sidewall of the light guide plate. Each light source corresponds to a different pattern. A storage unit stores lighting sequence information and a controller controls the turning on and off of the plurality of light sources in accordance with the lighting sequence information, thereby illuminating the patterns. Visible light emitted from the light sources to enters the light guide plate via an incidence surface. The prisms making up the patterns reflect only the visible light emitted from a light source corresponding to a particular pattern.