LIGHT COLLECTING STRUCTURE FOR BUILDING

PROBLEM TO BE SOLVED: To satisfactorily collect light by providing a light collecting window on a roof, a translucent section between the second-story floor and the first-story ceiling guiding the light collected by the light collecting window to the first-story floor, and lighting facilities not hindering the light transmitting the translucent section. SOLUTION: A translucent section 1 is formed with a second-story floor panel 10 having a translucent window 11 and a first-story ceiling panel 20 having a translucent window 21 provided correspondingly to the translucent window 11 provided on the second-story floor panel 10, and lighting facilities 30 are provided on both sides in the translucent section 1. For the light collection in the fine daytime, the light collected from a skylight window 2 illuminates the second-story floor, transmits the translucent window 11 of the second-story floor panel 10, transmits the translucent window 21 of the first-story ceiling panel 20 below, and illuminates the first-story floor. For the light collection in a cloudy or rainy day and at night, luminaires 32 are lighted to illuminate both the first-story floor and the second-story floor, and the light emitted to the back face direction of the luminaires 32 is reflected by reflectors 31. The prescribed position of the first story can be illuminated by the light collected through the second-story roof.