The invention concerns a lighting module comprising a concave reflector, and at least one light source disposed in the concavity of the reflector in order to illuminate at least upwards, and a lens situated in front of the reflector and light source. The reflector is associated with a flat plate, the top face of which is reflective in order to bend the beam coming from the reflector, the said plate comprising a front end edge able to form the cutoff in the lighting beam. The reflector is determined so as to transform a spherical wave surface coming from the source into a wave surface boiling down to an arc of a circle situated in the plane of the plate, and the lens is of revolution about an axis orthogonal to the plane of the plate and passing through the center of the said arc of a circle.