| 摘要 |
PURPOSE:To vary an angle corresponding to a face angle of each prism so as to gradually incrrase toward the lower part from the upper part, and to generate no shadow where no light beam comes due to refraction of light, with regard to a shadowless prism plate which makes sunlight shine upon a place which becomes shade of a building by refracting a solar light beam by the prism plate. CONSTITUTION:In figure, 4 shows a transparent plate, and on its surface, there is prism plate constituted of a prism whose section consists of a plurality of horizontal saw-tooth parts 41, an angle Ai corresponding to a face angle of each prism is varied so as to gradually increase toward the lower part from the upper part, the prism corresponding to the adjacent part of the upper part transmits light so that it travels almost straight, and the prism being nearer the lower part refracts light gradually large. A light beam shining upon near the upper part of the prism plate travels in the direction of (e), which is almost a straight line, that which shines upon the lower part suddenly turns and travels in the direction (c), the intermediate one is refracted to the intermediate extent, and as a result, the place between (c) and (e) is lighted up almost equally, and no shadowy part is generated anywhere. |
