Right: American custom designed suntracker or heliostat which follows the sun and directs light up into a mirror which sends it down a lightshaft.  
Left: Diagram showing sunlight beamed down the light shaft by the heliostat system and reflected at the bottom into a lensed light tube which acts like a linear light fixture.
Above: Cupola housing heliostasts.
Right: Japanese custom heliostat which replaced the American one and beams sunlight directly down the lightshaft.
Above: Light tube with sunlight inside [65ftc.]

Active Solar Optics System [ASO]  


The ASO system employs a suntracker or heliostat to follow the daily path of the sun across the sky and beam the sunlight down a shaft to a target area. This system can be very precise and the beam can be no larger in diameter than a pencil with the right lenses. It allows for the delivery of part of the 10,000 FTC. of sunlight to the same place all day long. The heliostat is guided by simple technology amounting to the equivalent of a clock and a compass and requires very little electrical energy(which could be supplied by photovoltaics) to operate it. A system of multiple shafts and light tubes can be designed.
Above: Sunlight beamed straight down onto floor 100 ft. below [400 FTC.]