The effect of spacing between luminaires on visual comfort

Using luminaires with high luminance efficiency may reduce the required number of luminaire installations in the ceiling, and as such effectively decrease the cost and save energy. However, it may also result in a negative effect on visual comfort. In this paper, we describe a subjective experiment to investigate the effect of spacing between luminaires on visual comfort. Results show that it´s possible to arrange luminaires with high luminance efficiency at a larger spacing, while still achieving lighting of comparable comfort and of similar perceived space brightness, when controlling the average horizontal illuminance of the lighting on the working area.