A backlight unit includes a light source which emits a first light, a light guide bar extending in a first direction, where the light guide bar receives the first light through an incident surface thereof, and guides the first light to convert the first light to a second light, and a control pattern disposed on a surface of the light guide bar, which extends in the first direction, where the control pattern converts the second light to a third light, and has a shape extending in the first direction to control an exit angle of the third light.