The subject matter of the invention is a light assembly which comprises means for emitting and means for focusing one or more light beams for the lighting or the signaling of a vehicle. It also comprises a mask which extends below the focusing means. This mask has at least a first surface that can be seen by any person passing close to the vehicle and at least a second surface opposite the first surface.The mask is made from a dark diffusing material and a reflective material coating is deposited on part of the second surface while leaving a portion of this second surface free of reflective coating. Additional light-emitting means are placed opposite the second surface, such that the light rays emitted by the additional light-emitting means can pass through the mask via the portion free of reflective coating.