A sign lighting arrangement including a luminaire located in a predetermined position in front of a rectangular sign is disclosed herein. The luminaire includes a light source supported by an opaque housing, the uppermost edges of which lie in a common plane with the light source and the bottom edge of the sign. In this manner, direct light from the light source is prevented from passing under the sign (positive bottom edge cut-off). The luminaire also includes a reflector having lateral edge portions located in a fixed position relative to the luminaire's light source and the sign. The reflector and particularly these lateral edge portions are specifically contoured so that the lateralmost vertical edges of the reflected light substantially coincide with the side edges of the sign. Thus no reflected light passes beyond these side edges (positive side edge cut-off). A refractor is provided one purpose of which is to aid in achieving positive side edge cut-off.
A new and improved lighting system for illuminating signs such as billboards and the like which increases the amount of light illuminating the light from a light source by 15 to 20% as compared with previous systems and decreases the variance of illumination intensity by 50%.