Researchers at Korea's ETRI (Electronics and Telecommunications Research Institute) developed transparent graphene-based electrodes for OLED panels. The researchers say that these new electrodes improve the transparency and "image quality" of OLEDs by 40 to 60 percent, compared to current silver-based electrodes.
A flexible OLED prototype (LGD)
The researchers explain that current metal (mostly silver) based electrodes have a limited viewing angle because of their internal light reflection, and the external light reflection affects the image quality. Graphene electrodes are more transparent and reduce the reflectance by 40-60 percent.
ETRI says that this technology will be especially suitable for transparent OLEDs and white-OLED based panels (WRGB, or WOLED technology). The scientists aim to continue this research and improve the graphene electrode performance.
Transparent graphene-based electrode for OLED panels is not a new idea. The German Fraunhofer Institute is developing such electrodes for OLED panels as part of the GLADIATOR project, and recently Graphene 3D Lab demonstrated a printed OLED lighting device with a graphene electrode. Plastic Logic (FlexEnable) demonstrated an E Ink display with graphene electrodes back in 2014, and the company is also working on an OLED panel using similar electrodes.