LIGHT TRANSMISSION DEVICE, BACKLIGHT UNIT, AND LIQUID CRYSTAL DISPLAYING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a light transmission device which can heighten the brightness of a light guide plane, and to provide a backlight unit and a liquid crystal displaying device equipped with such a light transmission device. SOLUTION: The light transmission device 2 of the backlight unit 1 comprises a light guide plate 22 with a plurality of convex parts 25, and a light transmission plate 23 comprising concave parts 28 corresponding to respective convex parts 25, and a plurality of projected parts 29 totally reflecting the light guided from the concave parts 28. Concave parts 28 of the light transmission plate 23 are fitted to the convex parts 25 of the light guide plate 22.