| 摘要 |
PROBLEM TO BE SOLVED: To provide a configuration with higher heat radiation efficiency by improving such a structure that a metal plate having a concavo-convex pattern extending in a vertical direction is attached to the rear side of a lamp type direct backlight of a liquid crystal display device and that heat can be radiated by ventilation induced in the concavo-convex pattern.SOLUTION: A backlight unit 3 comprises: a plurality of light-emitting diodes 4 which are disposed on a liquid crystal display panel 2 side of projection lines 9 of a metal plate 8; and a chassis 12 which houses the metal plate 8 and includes a top plate 14 and a bottom plate 13 having openings 14a, 13a, respectively, each communicating a space in a recessed line 11 between adjoining two projection lines 9. By this configuration, heat conduction is induced from the light-emitting element 4 to the metal plate 8, and ventilation is induced by the heat of the metal plate 8, with an air stream from the opening of the bottom plate 13 as an entrance, through the space in the recessed line 11 to the opening 14a of the top plate 14 as an exit, which cools the metal plate 8. By the double effects, the backlight unit 3 as a whole is efficiently cooled. |
