Provided is an illumination device including a display panel including a first surface and a second surface that is opposite to the first surface, the display panel being configured to output light including image information through the first surface, a light source configured to emit light, the light source being spaced apart from the display panel in a direction away from and normal to the second surface of the display panel, a window panel including a first area configured to transmit the light output from the display panel and a second area configured to transmit the light emitted from the light source, and a light transmitting unit provided between the window panel and the light source, the light transmitting unit configured to transmit the light emitted from the light source to an object through the second area, the light transmitting unit including at least one meta-surface.