The amount of visible light outdoors under a clear sky is greater than one imagines, and the system can adequately illuminate a room with 1/10 of the outdoor illuminance. For
example, at noon on the spring and autumn equinoxes, when the sun is over the equator, outdoor illuminance is 100,000 lx. At the same moment, a SOLIGHT unit provides luminous flux of 13,000 lm for a room, equal to the
visible light provided by four 40 W fluorescent lamps (power consumption: 150 W), nine 100 W incandescent lamps (power consumption: 870 W), or one 400 W mercury lamp (power consumption: 240 W).
consumption of a SOLIGHT is less than 0.9 W. But, equipped with a photovoltaic panel, it does not use any power from utility grids.
A microprocessor in the unit automatically controls solar tracking using
preprogrammed data on the movement of the sun. In addition, the amount of light passing through the prism discs can be regulated by remote control. This dimming mode operation makes it possible to keep a room
comfortably illuminated, even under strong direct sunlight in summer. The light introduced by the flat prism set of a SOLIGHT unit is scattered throughout the room by a light distribution plate shielding the unit. Two
types of plate, a diffuser type and a spotlight type, are available for use according to the application and location.
This daylighting system can direct light to a given place even with the sun at low altitude
early in the morning, in the late afternoon or during the winter, and deliver relatively stable amounts of light all year round. Even under cloudy skies, it can bring the same level of light into a room as an opal
skylight dome. The plastics used for the components transmit only visible light, screening out harmful ultra violet rays and infrared rays which would add a heat load to the room. In this manner, the system suppresses
glare and does not raise room temperatures excessively in summer.
A mechanical engineering company introduced this daylighting system to its newly built works as part of an energy-saving strategy. One hundred
SOLIGHT units mounted on the building at intervals of 7 m deliver enough light to the floor from the 7.5 m high ceiling to make artificial lighting in the works during the daytime almost unnecessary. People working here
feel that the natural daylighting increases their comfort.