Abstract: A luminaire comprising at least one light source arranged in a housing for emitting a light beam through a light-transmitting plate of the housing, with the special feature that said housing is provided with a diffuse reflective coating having a water-based solvent and a binder. The binder is on the basis of either a polymer selected from the group formed by compounds of the following structural formula (I): wherein R1 comprises an element chosen from the group Br, Cl, I, F, H, wherein R2 comprises an element chosen from the group Br, Cl, I, F. H, or an alkyl group, wherein R3 comprises an element chosen from the group Br, Cl, I, F, H, or COOCH3, and wherein R4 comprises an element chosen from the group Br, Cl, I, F, H, OH, or vinylether, or an organically modified silane of the sol-gel type, wherein said diffuse reflective coating is applied as a diffuser on the light-transmitting plate.