US Patent 7380958 Backlight unit having lamps disposed with various distances

A backlight unit includes a plurality of lamps which generate a light; a case which houses the lamps; and a lamp holder that holds the lamps, the lamp holder being placed in the case, wherein a distance between first adjacent lamps is different from a distance between second adjacent lamps. Further preferred, a distance from a bottom surface of the case increases from an edge of the case to the center portion thereof.