Pure visible light – without the uncomfortable infrared or the damaging ultraviolet – is conducted through the optical fibers into the building. The fibers feed light into an acrylic rod, the non-electrical equivalent of the fluorescent tubes between which it is sandwiched in the commercial hybrid lighting fixture. The sunlight, which would otherwise continue in a straight line, is diffused outward into the room by means of hundreds of tiny scratches on the surface of the rod. One HSL 3000 is capable of lighting approximately 1000 square feet.
This is a very simple idea, to direct sun light into fiber optics. It's so much better than making wholes in the roof.