| 摘要 |
PROBLEM TO BE SOLVED: To prevent occurrence of uneven luminance on the screen of a liquid crystal display device by using polyethylane naphthalate as a material for a base material sheet to inhibit deflection due to heat of a lamp. SOLUTION: A base material sheet 2 is formed out of polyethylane naphthalate to be excellent in dimensional stability to heat and inhibit deflection due to heat of a light diffusion sheet 1. A light ray 9 is emitted from a lamp 7 and guided into the inside of a light guide plate 8 to be reflected by a reflection dot on the back of the light guide plate 8 or a reflecting sheet, and radiated to an upper light diffusion sheet 1. The upward radiated light ray 9 is uniformly diffused in passing the light diffusion sheet 1, and further sent to an upper prism sheet or the like. Even if the light diffusion sheet 1 is heated by heat of the lamp 7, deflection of the light diffusion sheet 1 is inhibited by a base material sheet 2 excellent in heat resistance. By the thus formed light diffusion sheet 1, uneven luminance on the screen of a liquid crystal display device can be inhibited. |
