An illumination device includes a plurality of light source blocks defined by a first partition wall and a second partition wall, the light source blocks being provided with LEDs. The illumination device is capable of adjusting a luminance of each of the plurality of light source blocks. A projection section to diffuse the light is provided on a vertex of the first partition wall. As a result, it is possible to prevent a luminance irregularity and a color irregularity from occurring between illumination areas when adjusting the respective luminance in each of the plurality of illumination areas.