Patent ID: 9059420
Filing Date: 2015-06-16
Classification: G02B,H01L

Abstract:
1. An organic EL element comprising: a transparent supporting substrate; a diffraction grating which comprises a concavity and convexity layer having first concavities and convexities formed on a surface thereof and which is disposed on the transparent supporting substrate; and a transparent electrode, an organic layer, and a metal electrode which are stacked in this order on the diffraction grating and formed into such shapes that a shape of the first concavities and convexities formed on the surface of the diffraction grating is maintained, the organic layer comprising at least a light emitting layer, wherein the organic EL element satisfies the following conditions (A) to (C): (A) when a Fourier-transformed image is obtained by performing two-dimensional fast Fourier transform processing on a concavity and convexity analysis image obtained by analyzing the shape of the first concavities and convexities by use of an atomic force microscope, the Fourier-transformed image shows a circular or annular pattern substantially centered at an origin at which an absolute value of wavenumber is 0 μm (B) standard deviations of depth distributions of the first concavities and convexities and second concavities and convexities are each 15 to 100 nm, the second concavities and convexities being formed on a surface, on a side facing to the organic layer, of the metal electrode, each of the standard deviations being determined on the basis of a concavity and convexity analysis image obtained by analyzing a shape of the corresponding concavities and convexities by use of an atomic force microscope, and (C) a ratio of a change in the standard deviation of the depth distribution of the second concavities and convexities relative to the standard deviation of the depth distribution of the first concavities and convexities is +15% to −15%.