Journal of the Optical Society of Korea

Optical Society of Korea (한국광학회)
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Frequency Dependency of Multi-layer OLED Current Density-voltage Shift and Its Application to Digitally-driven AMOLED

  • Kim, Hyunjong (Department of Electrical Engineering and Computer Science, and Inter-university Semiconductor Research Center, Seoul National University) ;
  • Kim, Suhwan (Department of Electrical Engineering and Computer Science, and Inter-university Semiconductor Research Center, Seoul National University) ;
  • Hong, Yongtaek (Department of Electrical Engineering and Computer Science, and Inter-university Semiconductor Research Center, Seoul National University)
  • Received : 2012.04.13
  • Accepted : 2012.05.03
  • Published : 2012.06.25
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Abstract

We report, for the first time, operation frequency dependence of current density-voltage ($J_{OLED}-V_{OLED}$) shift for multi-layer organic light-emitting diodes (OLEDs). When the OLEDs were electrically stressed for 21 hours with 50% duty voltage pulses at 60, 120, 240, and 360 Hz, the JOLED-VOLED shifts were suppressed by half for 360 Hz operation compared with 60 Hz operation, but with little change in emission efficiencies. This frequency dependent $J_{OLED}-V_{OLED}$ shift is believed to be commonly observed for typical multi-layer OLEDs and can be used to further improve lifetime of digitally-driven active-matrix OLED displays.

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References

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