Fig. 5
Optical simulation. a Simulated photon distribution of all loss channels in dependence of the electron-transporting layer (ETL) thickness in the present white organic light-emitting diodes (WOLEDs). Most generated photons remain in waveguided and evanescent modes. b Calculated extraction efficiency from the simulated photon distribution of the present WOLEDs, HTL denotes the hole-transporting layer. The pentagram symbol represents the theoretical maximum external quantum efficiency (21.7%) in our proposed structure. c The experimental and theoretical spectra of the WOLEDs according to the monochrome blue and orange spectra. d Angular resolved spectral radiant intensity (SRI) of the present WOLED with the electron-transporting layer thickness of 60 nm at the brightness of 1000 cd m−2. The displayed is the SRI in dependence of the wavelength λ and polar angle θ
