A light source determining apparatus for determining if a light source is a specific type light source is disclosed. The light source determining apparatus comprises: a light filtering device, comprising at least one first region and at least one second region, wherein the first region can pass only light with a specific frequency, where the second region can pass not only light with the specific frequency but also light with other frequencies; and a determining unit, for determining if the light source is the specific type light source, according to luminosity that the light source respectively generates for the first region and the second region.