The present invention provides a liquid crystal display device of high
quality having high brightness and uniform brightness distribution by
focusing the light radiation direction from a light guide plate in the
vertical direction with respect to a light radiation surface of the light
guide plate. The liquid crystal display device includes a liquid crystal
display panel and a flat lighting device which radiates an illumination
light to a back surface of the liquid crystal display panel. The flat
lighting device includes a light guide plate which has an upper surface
facing a back surface of the liquid crystal display panel in an opposed
manner and constituting a light radiation surface and a bottom surface
which is arranged opposite to the upper surface. One LED is arranged at a
first corner portion of the light guide plate and another LED is arranged
at a second corner portion of the light guide plate arranged adjacent to
the first corner portion. By forming reflection surfaces which are
inclined toward the upper surface from the bottom surface of the light
guide plate and inclined surfaces which abut on the reflection surfaces
on the lower surface of the light guide plate, the light radiation
direction from the light guide plate is focused in the vertical direction
with respect to the upper surface of the light guide plate.