A front light includes: a light source, a light guide plate, and a plurality
of
prism-shaped lenses, each being in contact with a lower surface of the light guide
plate. A cross-section of each of the prism-shaped lenses, in a plane perpendicular
to the side surfaces thereof, has a shape of equally-sided trapezoid. An obtuse
angle out of the equally-sided trapezoidal cross-section and
a critical angle c for the total reflection of the prism-shaped lenses satisfy
the relationship of 90 out90+c. When the
light emitted from the light source enters the prism-shaped lens, the light is
allowed to be reflected at a side surface defined by side-edges of the trapezoidal
cross-section and thereafter exit through a lower surface. Thus, the light can
illuminate pixel electrodes in a liquid crystal panel from a direction normal thereto.