| 摘要 |
PROBLEM TO BE SOLVED: To provide a back light lighting system, which can improve the evenness of the light emitted from a flat surface and of which weight can be reduced and of which cost can be lowered. SOLUTION: A part of the light emitted from a pair of fluorescent lamps 3a, 3b provided in opposite side surfaces of a main body case 1, of which top surface is opened, is directed to a central part of the main body case 1 by curved reflecting bodies 5a, 5b, and the light transmitted to a central part by a reflecting plate 6, which is arranged at a central part of a bottom surface of the main body case 1 and which has the triangle cross section, to a central part of a top surface of the main body case 1 so as to improve the illuminance of the central part, and while the top surface of the main body case 1 is provided with a gradation plate 8 printed with silver metallic dots on the surface of a transparent acrylic plate, of which transmittance of light is gradually reduced as it comes close to the fluorescent lamps 3a, 3b, so as to obtain the even illuminance of a diffusion plate 10 formed in the top surface of the gradation plate 8. |
