Multilayer Langmuir-Blodgett films as diffractive external 3D photonic crystal in blue OLEDs
Year: 2016
Journal: Opt. Express
Authors: Dumur, F; Reculusa, S; Mruczkiewicz, M; Perrin, M; Vignau, L; Fasquel, S
Three-dimensional Langmuir-Blodgett films made of silica beads are theoretically and experimentally investigated in order to improve the relatively small efficiency of blue OLEDs. Using films made of 5 layers of beads, we fabricated OLEDs emitting at 476 nm, and measured a gain of around 40% on their external quantum efficiency. An optical model has been developed to accurately handle the fact that the organic emitting layer and the photonic extraction layer are separated by a distance greater than 1000 wavelength. The latter also permits to describe rapidly this three-dimensional optical OLED cavity, without redoing all the numerical simulations when the optical properties of the organic layers are changed (material index, thicknesses). (C) 2016 Optical Society of America
