| 摘要 |
PURPOSE:To uniform the brightness distribution on the surface of a light guide by using an aperture lamp as a fluorescent lamp and setting its aperture opposite a reflecting plate side. CONSTITUTION:When the aperture fluorescent lamp 4 is set having its aperture part 3 opposite the side of a reflecting plate 2, high-brightness light 5 from the aperture part is guided to both end parts of a diffusing plate 1 and low- brightness light 6 from the part except the aperture part is guided to the center part of the diffusing plate 1 respectively. Therefore, the center part of the diffusing plate 1 respectively. Therefore, the center part of a normal fluorescent lamp where the brightness of the brightness distribution 7 is high decreases in brightness and both end parts where the brightness is low increases; and those two variations uniform the brightness distribution under set conditions in this case. Thus, one aperture fluorescent lamp satisfies the set conditions, so a plane light source is obtained on the top surface of the diffusing plate and the efficiency is not spoiled. |
