Luminous-Ceiling Lighting

The paper deals with the design of complete luminous ceilings lighted from above. Such lighting compares favorably in coefficient of utilization with other methods and has definite advantages over the louverall ceiling. For brightness uniformity, the normal spacing between rows of fluorescent lamps should not exceed twice the distance between lamps and translucent plates. Also, the outside rows of lamps should be spaced three quarters of normal spacing, and the distance from them to the sides of the lightbox should be one-quarter of normal spacing rather than the one-half generally used in the past.