ORGANIC EL ELEMENT, ORGANIC EL LIGHTING DEVICE, ORGANIC EL ELEMENT LIGHT SOURCE AND ORGANIC EL DISPLAY DEVICE

To provide an organic EL element having high extraction efficiency of light, and a lighting device, a light source and a display device including the organic EL element.SOLUTION: The present invention relates to an organic EL element including a transparent substrate, and a light-transmitting rugged layer, a light-transmitting anode, an organic EL layer and a cathode disposed in the described order on the transparent substrate. In the organic EL element, the light-transmitting rugged layer has a rugged pattern in a part of or the whole of a surface on the organic EL layer side. When the rugged pattern is observed on a cross section perpendicular to a light-exiting surface of the transparent substrate, the rugged pattern has at least one flexion point on an outer edge curved line of the rugged pattern along the cross-sectional shape, in which an angle formed by a tangential line at each flexion point and the plane of the transparent substrate is 5° or more and less than 25°. The rugged shape of the light-transmitting rugged layer is transferred to a surface on at least the organic EL layer side of the cathode. The present invention includes a lighting device, a light source or a display device including the above organic EL element.SELECTED DRAWING: Figure 1 【課題】高い光取出し効率を有する有機ＥＬ素子並びに当該有機ＥＬ素子を含む照明装置、光源及び表示装置を提供すること。【解決手段】本発明は、透明基板、前記透明基板上に設けられた透光性凹凸層、透光性の陽極、有機ＥＬ層及び陰極をこの順に含む有機ＥＬ素子に関する。当該素子は、前記透光性凹凸層は、前記有機ＥＬ層側の面の一部又は全体に凹凸を有し、前記凹凸を透明基板の光射出面に対して垂直な断面で見た場合に、前記凹凸は、その断面形状に沿った凹凸の外縁曲線上に少なくとも１つの変曲点を有し、前記変曲点のそれぞれにおける接線と、透明基板の平面とのなす角度が５°以上、２５°未満であり、透光性凹凸層の凹凸形状が陰極の少なくとも有機ＥＬ層側の表面上に転写される。本発明は、この有機ＥＬ素子を含む照明装置、光源又は表示装置を包含する。【選択図】図１