| abstract |
Disclosed is an organic EL element wherein light is extracted at a high efficiency and visibility is improved. The organic EL element is provided with a pair of electrodes (2, 4) and an organic layer (3) having at least one organic light-emitting layer. A fine periodic structure (5), in which the sequence period is less than or equal to the wavelength of light generated at the organic light-emitting layer, is formed on the surface of the electrode (first electrode (2)) on the light extraction side and/or the surface of a substrate (1) disposed on the light extraction side. The refractive index of a region neighboring the aforementioned electrode on the side opposing the organic layer (3) is represented by n1, the refractive index of the aforementioned electrode is represented by n2, and the refractive index of the organic layer (3) neighboring said electrode is represented by n3. When n1=n3, the relationship n1=n2=n3 or n2=n1=n3 is established, and when n3=n1, the relationship n2=n3=n1 or n3=n2=n1 is established. As a consequence, it is possible to prevent incident light having an angle less than the critical angle from being reflected, and to improve the light extraction efficiency of incident light having an angle equal to or greater than the critical angle. Moreover, it is possible to reduce outside light from being reflected. |