Korean Journal of Optics and Photonics (한국광학회지)

Optical Society of Korea (한국광학회)
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Effects of a Dielectric Multilayer Mirror on the Lighting Efficiency of Organic Light-Emitting Diodes Studied by Optical Simulation

유전체 다층 거울이 유기발광다이오드의 광효율 향상에 미치는 영향에 관한 광학 시뮬레이션 연구

  • 이성준 (한림대학교 전자물리학과) ;
  • 고재현 (한림대학교 전자물리학과)
  • Received : 2015.05.11
  • Accepted : 2015.05.29
  • Published : 2015.06.25
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Abstract

The effects of a dielectric multilayer mirror on the efficiency of organic light-emitting diodes (OLEDs) were investigated by using optical simulation. Adoption of a dielectric mirror consisting of alternating SiN and $SiO_2$ layers narrowed the emission spectrum due to the microcavity effect, and increased the outcoupling efficiency by a few percent. The layer thicknesses of the dielectric mirror were adjusted to change the wavelength of the resonance mode, which may be used to increase the color purity.

본 논문에서는 유전체 다층 거울을 이용해 구성된 파브리-페롯 미소공진 구조가 유기발광다이오드(OLED)의 광효율에 미치는 영향을 유한차분 시간영역법과 광선추적법을 결합해 분석하였다. SiN과 $SiO_2$ 층을 교대로 쌓아 구성한 유전체 다층박막의 적용은 미소공진 효과를 강화시켜 OLED의 발광 스펙트럼의 협소화를 유도하였고 광추출효율도 수 % 증가하였다. 유전체 다층박막의 두께를 최적화함으로써 특정 파장에 대해 미소공진 효과를 일으킬 수 있었고 이는 OLED 발광색의 순도를 증가시키는데 활용될 수 있다. 광추출효율을 극대화하는 전자수송층의 최적 두께는 발광파장에 따라 달라졌는데, 이는 유기층 물질이 보이는 굴절률의 분산 때문인 것으로 생각된다.

Keywords

References

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