Enhancement of Light Extraction Efficiency in OLED with Periodic Nano-Structure

To improve the light-extraction-efficiency of organic light emitting diode (OLED), we introduced novel photonic crystal slab (PCS) structures with Taper unit cells into the interface of ITO layer and glass substrate. By optimizing the geometric parameters, we proved that the PCS with triangular lattice of Taper cells was more effective in reducing the energy of guided wave trapped in OLED than the traditional PCS structures. Light-extraction-efficiency of OLED based on this PCS increased by 95.26%. Physical mechanisms of light- extraction-efficiency enhancement in these structures are further discussed.