Abstract: A luminaire for roadway lighting using a one-piece reflector developing at least two collimated beams in each longitudinal direction. The collimated beams impinge on sloping faces of a refractor to diverge the beams into a regular pattern covering the street with a sharp cutoff at predetermined longitudinal distances from the luminaire. The refractor employs a compressed parabola comprised of radial sections of comparatively large focal length with steps and risers. The complex shape of the one-piece reflector may readily be produced by a reflector finish applied to a molded plastic matrix. In the luminaire, the prismatic surfaces of the inclined walls of the refractor diverge the formerly collimated beams in a carefully controlled manner to produce very uniform distribution of light.

Abstract: A luminaire for roadway lighting using a one-piece reflector developing at least two collimated beams in each longitudinal direction. The collimated beams impinge on sloping faces of a refractor to diverge the beams into a regular pattern covering the street with a sharp cutoff at predetermined longitudinal distances from the luminaire. The refractor employs a compressed parabola comprised of radial sections of comparatively large focal length with steps and risers. The complex shape of the one-piece reflector may readily be produced by a reflector finish applied to a molded plastic matrix. In the luminaire, the prismatic surfaces of the inclined walls of the refractor diverge the formerly collimated beams in a carefully controlled manner to produce very uniform distribution of light.

Abstract: An improved railroad crossing signal includes a deep dish parabolic reflector and an essentially flat plastic lens angled forward at the top relative to the axis of the reflector. The lens includes prism elements for laterally dispersing parallel light from the reflector more toward the crossing highway at near and far distances than toward the adjacent land. The lens also includes prism elements for vertically dispersing a portion of the light to produce uniform brightness before the signal.