Luminaires for illumination of vertical surfaces of predetermined dimensions such as billboards or similar signs, the invention in several embodiments takes the form of reflector assemblies capable of directing light from a
light source disposed within each of said luminaires either directly to the vertical surface or to refractive structures located on the luminaires for redirection of light to the vertical surface for even illumination of said surface with minimal
light pollution from “spill” light. Lamps used in embodiments capable of providing asymmetrical light distributions are located toward one or the other of side portions and are preferably vertically oriented. A main reflector is curvilinear in conformation and functions in concert with a secondary reflector located directly behind the lamp to direct light onto desired portions of a vertical surface. Luminaires configured according to the invention also utilize side reflectance panels for
light control and for maximizing light directed onto a vertical surface, said luminaires also preferably including
refractive lens elements for redirection of light onto the vertical surface. The reflector assemblies of the invention are mounted within weather-tight housings, the refractive structures conveniently being disposed on or formed integrally with a transparent glass or plastic cover that completes the housing, said cover being located between the lamp and the vertical surface to be illuminated. Efficiencies occasioned by the present luminaires permit illumination of billboards and similar signs of standard dimensions with only two of the luminaires and with full and even illumination with minimal light
spillage, a capability approached previously in the art only with a greater number of luminaires.