A light guide unit includes a light guide plate and a plurality of light-exiting protrusions. The light guide plate includes a light-entering surface, an upper surface connected to the light-entering surface and a lower surface facing the upper surface. The light-exiting protrusions protrude from the upper surface of the light guide plate to have a cylindrical shape in which a cross-section size thereof increases in a direction away from the upper surface of the light guide plate, the light-exiting protrusions being disposed in a light control area which is turned on or off by a microelectromechanical system shutter. Light guided by the light guide unit to the light control area exits through the light-exiting protrusions.