Patent ID: 7659949

Claim:
A backlight unit, comprising: a box type case having a sidewall and an upper opening; an optical member provided mainly with a light source and an optical sheet contained in the box type case; and a supporting frame in a frame shape securing the optical member in place by being fitted in the opening of the box type case and supporting a liquid crystal display panel; a first engaging portion being provided to an inside of the sidewall of the box type case, and a second engaging portion being provided to an outer surface of the sidewall of the supporting frame being fitted in the upper opening of the box type case, the second engaging portion being a U-shaped groove with a predetermined depth and having an opening at an upper portion of the supporting frame and locking means being attached to a bottom wall surface of the U-shaped groove, the locking means being engaged with and locked by the first engaging portion as the first and second engaging portions engage each other, wherein the bottom wall surface of the U-shaped groove has a protruding portion protruding by a predetermined length from an outer surface of the sidewall, and the locking means is formed by a projection raised upward from a top edge of the protruding portion of the bottom wall surface.