Eliminate the angular dependence of blue emission top-emitting organic light-emitting devices by integrating gratings

We demonstrate that the angular-dependence effect in blue emission top-emitting organic light-emitting diodes (TOLEDs) can be resolved in a very simple and effective way via introducing gratings and filling process. In this method, the shift of the peak emission wavelength with the viewing angle is successfully suppressed in TOLEDs. A desired emission pattern of approximately Lambertian is obtained. Moreover, we can observe almost the same current density and luminance in TOLEDs with and without gratings. Their maximal luminance are 10,776 cd/m2 and 11,290 cd/m2, respectively.