Recent Progress on Voltage Drop Compensation in Top Emission Organic Light Emitting Diodes (OLED)

  • Jeong, Byoung-Seong (Department of Hydrogen and Renewable Energy, Kyungpook National University)
  • Received : 2020.03.09
  • Accepted : 2020.03.23
  • Published : 2020.03.31


The voltage drop due to the thin cathode film at the large size top emission OLED panel was successfully compensated with making electrical contact between thin cathode and anode auxiliary electrode by 355nm wavelength of laser. It was found that the luminance uniformity dramatically increased from around 15% to more than 80% through this electrical compensation between thin cathode and anode auxiliary electrode. Moreover, the removing process for EL materials on the anode auxiliary electrode process by laser was very reliable and stable. Therefore, it is thought that the EL removal method using laser to make electrical contacts is very appropriate to mass production for such a large size top emission OLEDs to obtain high uniformity of luminance.



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