A light source device may include a first light source, a second light source, a light guide plate (LGP) configured to guide a light incident from at least one of the first light source and the second light source, an optical film configured to form a distribution of directional light by controlling a progress path of a light output from the LGP, and a controller configured to control activation of at least one of the first light source and the second light source in order to control the distribution of directional light.