Photonic crystal organic light emitting device having high extraction efficiency

Abstract

Disclosed is a photonic crystal organic light emitting device. The device comprises a transparent substrate having a concavo-convex structure in an upper surface thereof, a transparent electrode layer formed on the transparent substrate, a hole conduction layer comprised of an organic EL material and formed on the transparent electrode layer, an electron conduction layer comprised of an organic EL material and formed on the hole conduction layer, and a cathode layer formed on the electron conduction layer. Here, a photonic crystal period due to the concavo-convex structure formed in the upper surface of the transparent substrate corresponds to a wavelength level of light generated at an interface between the electron conduction layer and the hole conduction layer. Therefore, a light extraction efficiency and a viewing angle are increased without degeneration of the image quality. Further, since the photonic crystal has an effective refractive value ranged between that of the transparent substrate and that of the transparent electrode layer, it has the same effect as in nonreflective coating, thereby simultaneously increasing the transmittance.