| 摘要 |
PCT No. PCT/DE82/00203 Sec. 371 Date May 20, 1983 Sec. 102(e) Date May 20, 1983 PCT Filed Sep. 20, 1982 PCT Pub. No. WO83/01085 PCT Pub. Date Mar. 31, 1983.With roof windows of any inclination and orientation, it should be possible to adjust the sunshade effect throughout the year and to have at the same time a good transparence to daylight. For this purpose, there is used a prismatic plate, flat at the outside, and which is provided at the inside with parallel prismatic bars having a surface free of a reflecting layer on a right angle side. According to the invention, the other surface on the other side is provided with a reflecting layer and forms with the non-reflecting surface a right angle. Furthermore, the prismatic bars are arranged perpendicularly to the intersection line which is defined by the intersection plane with which the solar beams, during the longest day, form the maximum incidence angle psi max with respect to the plane of the window. For the angle alpha of the base of the non-reflecting surface, a value may be selected with which there is obtained a sunshade effect and at the same time optimum conditions of transparency to daylight. |
