| 摘要 |
PURPOSE: To improve surface brightness and uniformity, and attain a thin type by arranging two comparatively thin circular fluorescent lamps on the same plane, and controlling the light by a reflecting surface so that brightness of a translucent cover surface becomes the specific brightness ratio. CONSTITUTION: First and second circular fluorescent lamps 4 and 5 having a tube outside diameter of 15 to 18mm and a ring outside diameter of 285 to 310mm and 360 to 390mm, are arranged almost on the same plane. A first reflecting means which is composed of a white member 6a and a reflecting member 6b and has a reflecting surface of a projecting curve, is arranged in a central part of a luminaire main body 1, and the radiating light is controlled in the central direction of the luminaire main body 1. A second reflecting means 7 is composed of a side reflecting surface 6c and an under surface 1b of the luminaire main body 1, and the radiating light is controlled in the outer peripheral direction by a recessed reflecting surface turned in the outer peripheral direction. Therefore, the brightness ratio of surface brightness of a central part to a brightness maximum value of a translucent cover surface is set not less than 0.55, and brightness and uniformity of the translucent cover surface is enhanced, and a luminaire can be thinned. |
