In rooms with little incident daylight, dynamically changing lighting scenes can provide important cues for the human sleep/wake rhythm. High illuminance and cool light colours have a stimulating effect in the morning and help us through the dip in energy levels in the middle of the day. In the evening, warm white light and lower illuminance prepares the human body for sleep.
Planar light ceilings or ceilings illuminated from within the room create conditions similar to daylight. This makes for better stimulation of special photosensitive cells in the eye that help keep hormone levels balanced. A number of studies confirm the positive effects of biologically effective lighting, which is already being successfullyused in offices, hospitals and schools.