| 摘要 |
PROBLEM TO BE SOLVED: To solve the problems found in the prior art that although a light diffusion type roof light window that is substantially contributable against energy saving due to direct utilization of solar light needs a mounting of lighting unit as an auxiliary light source and it was difficult to arrange or control it due to an appropriate intensity of illumination or uniformity ratio of illuminance, and although a regular maintenance management was essential for the lighting unit, in the case of large-scale and high ceiling buildings such as gymnasium, factory and warehouse or the like, it was necessary to make countermeasures such as installation of temporary scaffolds for maintenance management, installation of a catwalk for maintenance management and installation of an electric lifter device and the like.SOLUTION: This invention relates to a lighting device comprised of a light diffusion type roof light window in which an upper netted glass can be removed and its maintenance management can be carried out from a roof light window, and a lighting unit mounted just below the window and a lighting system using the lighting device. |
