An illumination apparatus includes a pair of substrates arranged oppositely to each other with a distance, and a light source disposed on a side surface of one of the pair of substrates. The illumination apparatus further includes an electrode that is provided on a surface of each of the pair of substrates and generates an electric field in a direction intersecting perpendicularly to the surface of the substrate. The illumination apparatus further includes a light modulation layer that is disposed at a clearance between the pair of substrates and is configured to exhibit scattering property or transparency to light from the light source, based on magnitude of the electric field generated by the electrode. The electrode includes a plurality of first electrode blocks on a surface of one of the pair of substrates.