| 摘要 |
PURPOSE:To lessen and prevent the leakage of light from the end edges where plural diffusing members are superposed on each other and to increase luminance by fixing the one-side edges along the direction orthogonal to the tube axes of light sources among the end edges where the plural diffusing members are superposed on each other. CONSTITUTION:The upper front edge 13C of a light transmission body 13 along the direction orthogonal to the tube axes of a pair of the fluorescent lamps 14, 15 and the lower front edge 18C of the lower diffusing plate 18 are fixed with a required adhesive to form a front edge fixed part 20a, the upper rear edge 18d of the lower diffusing plate 18 and the rear edge 19d of the upper diffusing plate 19 are fixed with the required adhesive to form a rear fixed part 20b. The incident light from a pair of the fluorescent lamps 14, 15 is irregularly reflected by the respective grooves 16 of the light transmission body 13 and is diffused double by the lower and upper diffusing plates 18, 19 and, therefore, the uniformity of the luminance on the light exit surface of the upper diffusing plate 18 is increased. In addition, the leakage of the light from the fixed parts 20a, 20b is lessened and prevented. |
