Furthermore, when fabricating such nanostructured OLEDs, the original structure geometry is not perfectly replicated into the OLED because corners are rounded and steep edges are flattened. The layers have thicknesses in the range of \(\) or even lower. OLEDs are thin-film devices made of multiple layers of organic and inorganic (semi-) conducting materials. Nevertheless, we demonstrate for nine different OLED structures that the radiation pattern of a homogeneous emission layer is approximated with an amplitude error of less than 5% by superimposing only four equally spaced dipoles at positions \(\pm \,(1/8, 3/8, 5/8, 7/8) \cdot \varLambda /2\), which avoid points of high symmetry. The position of an emitter with respect to the grating has a large influence on the radiation pattern. A 5 nm mesh resolution is determined as a good compromise between accuracy and simulation time. The necessary simulation domain size is derived by considering propagation length and field profile of the guided mode of a corresponding unstructured OLED. Radiation patterns of single dipole emitters placed in a sufficiently large simulation domain are superimposed to model the incoherent emission of a continuous emission layer. We present a theoretical study investigating simulation conditions for accurate radiation patterns employing the FDTD method. Nanostructures in OLEDs allow to manipulate the radiation pattern and direct light of a specific wavelength into a specific angle in the far field by resonant light outcoupling.
0 kommentar(er)
