Organic electroluminescent element and lighting device

摘要

An organic EL device comprises: a light-transmissive substrate; a transparent electrode; an organic emitting layer; and an opposing electrode. A light-extraction layer provided by layering a high refractive index layer adjoining the transparent electrode and a low refractive index layer adjoining the light-transmissive substrate includes recess-protrusion units each provided by a protrusion and a recess at an interface between the high refractive index layer and the low refractive index layer. In at least one of the recess-protrusion units, a distance from the interface between the high refractive index layer and the low refractive index layer to an interface between the transparent electrode and the high refractive index layer is equal to or more than an optical coherence length and a height of the protrusion, a width of the protrusion and a gap between the protrusion and another protrusion adjoining the protrusion across the recess is 1 μm or more.

主权项

1. An organic electroluminescence device, comprising:
a transparent electrode; an opposing electrode; an organic emitting layer provided between the transparent electrode and the opposing electrode; and a light-transmissive substrate, wherein a light-extraction layer is provided adjacent to a first side of the transparent electrode opposite to a second side of the transparent electrode facing the organic emitting layer, the light-extraction layer comprises a high refractive index layer and a low refractive index layer sequentially layered on the transparent electrode, the light-transmissive substrate is provided adjacent to the low refractive index layer, the light-extraction layer is placed above the opposing electrode, the high refractive index layer comprises a plurality of recess-protrusion units each provided by a protrusion and a recess at an interface between the high refractive index layer and the low refractive index layer, in at least one of the plurality of recess-protrusion units, a distance d1 from the interface between the high refractive index layer and the low refractive index layer to an interface between the transparent electrode and the high refractive index layer is 3 μm or more, and a height d2 of the protrusion, a width d3 of the protrusion and a gap d4 between the protrusion and another protrusion adjoining with the protrusion across the recess are 1 μm or more.