| 摘要 |
PROBLEM TO BE SOLVED: To suppress the generation of partial shadows and increase an amount of natural lighting when light is incident from a low altitude, by using a nearly dome-like translucent surface coating material to cover a natural lighting port and making the surface coating material in such a structure that a part of a side wall which is near a solar battery can bend incident light more strongly toward the solar battery side than a part which is away from the natural lighting port. SOLUTION: As for a surface coating material 5, a nearly dome-like material which has a shape of a turned-over bowl is used. The surface coating material 5 has a side wall section 5a and a ceiling section 5b which has a peak at the center. An inner face of the side wall section 5a stretches linearly in the circumferential direction and has a face of a Fresnel lens, with steps formed in the up and down direction, by which the incident light can be bent toward the solar battery 2 side. The Fresnel lens has such a structure that a part which is near a solar battery can bend incident light more strongly than a part which is away from the solar battery. |
