In a black light unit, a light-guide plate is provided with a cone pattern
to uniformly guide a light beam passing through a light input. A
light-path converter controls a progress direction of the light beam in
such a manner that the light beam outputted from the light-guide plate is
progressed in a direction perpendicular to a liquid crystal panel. A
diffusion sheet diffuses the light beam passing through the light-path
converter into the liquid crystal panel. A reflection of the light-guide
pattern and wall surface and the bright lines of the light input can be
minimized. The light efficiency can be improved and the manufacturing cost
can be reduced.
