PURPOSE: To prevent the degradation in display grade at the ends of a region effective for the liquid crystal display by forming a black body layer on the light exit surface outside the region effective for the liquid crystal display of a light transmission plate.

CONSTITUTION: This liquid crystal display device has the light transmission plate 12 which is arranged in parallel behind a liquid crystal display plate and a light source 13 which is arranged at the end of the light transmission plate 12. The device is extended with a diffusion film 14 for diffusing the light from the light transmission plate 12 toward the liquid crystal display plate. The black body 15 is formed on the light exit surface outside the region effective for the liquid crystal display of the light diffusion film 14. A black adhesive tape or the like made of a synthetic resin is usable for the black body layer 15. Then, the local heat conduction to the liquid crystal display plate at the end of the region effective for the liquid crystal display is lessened and the void phenomenon at the end of the liquid crystal display plate is relieved and prevented. The display grade is similarly improved by forming a light scattering and reflecting material near the end of the region effective for the liquid crystal display.