| 摘要 |
PROBLEM TO BE SOLVED: To provide a light-emitting device having a high light extraction efficiency. SOLUTION: The light-emitting device includes: an organic electroluminescent element having a pair of electrodes and a luminous layer provided between the electrodes; and a light transmissive thin plate provided in contact with one electrode out of the pair of electrodes. The one electrode out of the pair of electrodes shows optical transparency and its refractive index is 1.5-1.8; the light transmissive thin plate has a refractive index of 1.4-1.9; and a light diffusion layer is formed on one surface on a side separated from the luminous layer. The thickness of each member constituting the organic electroluminescent element is a thickness in which the ratio of light which becomes a thin-plate guided mode wave-guiding in the assumed light transmissive thin plate out of the light generated in the organic electroluminescent element becomes the maximum value×0.8 or more of the ratio when a light transmissive thin plate is assumed which has no light diffusion layer formed and of which one surface is a plane shape. COPYRIGHT: (C)2011,JPO&INPIT |
