반도체디스플레이기술학회지 (Journal of the Semiconductor & Display Technology)

한국반도체디스플레이기술학회 (The Korean Society Of Semiconductor & Display Technology)
권호 표지

투명 OLED 면광원 광 추출 향상 기술

Enhancement of Light Extraction from Transparent OLED Lighting Panels

  • 박준범 (조선대학교 정보통신공학과) ;
  • 신동균 (한국기술교육대학교 전기.전자.통신공학부) ;
  • 한승조 (조선대학교 정보통신공학과) ;
  • 박종운 (한국기술교육대학교 전기.전자.통신공학부)
  • Park, June Buem (Dept. of Information and Communication engineering, Chosun University) ;
  • Shin, Dong-Kyun (School of Electrical & Electronic & Communication Engineering Korea University of Technology and Education) ;
  • Han, Seun Gjo (Dept. of Information and Communication engineering, Chosun University) ;
  • Park, Jong-Woon (School of Electrical & Electronic & Communication Engineering Korea University of Technology and Education)
  • 투고 : 2017.11.27
  • 심사 : 2017.12.20
  • 발행 : 2017.12.31
PDF 다운로드
⟨ 이전 논문 다음 논문 ⟩

초록

We have investigated the light extraction efficiency of large-area OLED lighting panels with a microlens array (MLA) or external scattering layer (ESL) by ray tracing simulation. The application of MLA and ESL to transparent OLEDs (TOLEDs) with an auxiliary metal electrode is also studied. It is found that MLA shows higher light extraction efficiency, compared with ESL. However, we have demonstrated that ESL is more suitable for TOLEDs having dual-sided equal light emission. Namely, equal light emission from the front and rear surfaces of TOLED can be achieved by increasing the scattering particle density of ESL. To compensate for a loss in light emission induced by auxiliary metal electrode, we come out with an OLED structure partially covered with MLA at the outer surface of glass substrate, which is aligned with metal electrode. With this scheme, it is observed that the light extraction efficiency can be boosted more than 20% from opaque OLED and 50% from transparent OLED.

키워드

참고문헌

  1. S. Reineke, F. Lindner, G. Schwartz, N. Seidler, K. Walzer, B. Lussem, and K. Leo, "White organic lightemitting diodes with fluorescent tube efficiency," Nature, Vol. 459, pp. 234-238, (2009). https://doi.org/10.1038/nature08003
  2. K. Leo, "Organic LEDs look forward to a bright, white future," Science, Vol. 310, pp. 1762-1763, (2005). https://doi.org/10.1126/science.310.5755.1762
  3. T. Nakamura, H. Fujii, N. Juni, and N. Tsutsumi, "Enhanced coupling of light from organic electroluminescent device using diffusive particle dispersed high refractive index resin substrate," Optical Review, Vol. 13, pp. 104-110, (2006). https://doi.org/10.1007/s10043-006-0104-8
  4. S. Moller and S. R. Forrest, "Improved light out-coupling in organic light emitting diodes employing ordered microlens arrays," J. Appl. Phys., Vol. 91, pp. 3324-3327, (2002). https://doi.org/10.1063/1.1435422
  5. B. J. Matterson, J. M. Lupton, A. F. Safonov, M. G. Salt, W. L. Barnes and I. D. W. Samuel, "Increased efficiency and controlled light output from a microstructed lightemitting diode," Adv. Mater., Vol. 13, pp. 123-127, (2001). https://doi.org/10.1002/1521-4095(200101)13:2<123::AID-ADMA123>3.0.CO;2-D
  6. T. Nakamura, N. Tsutsumi, N. Juni and H. Fujii, "Thin-film waveguiding mode light extraction in organic electroluminescent device using high refractive index substrate," J. Appl. Phys., Vol. 97, pp. 054505-1-6, (2005). https://doi.org/10.1063/1.1858875
  7. V. Mann and V. Rastogi, "Dielectric nanoparticles for the enhancement of OLED light extraction efficiency," Opt. Commun., Vol. 387, pp. 202-207, (2017). https://doi.org/10.1016/j.optcom.2016.11.059
  8. J. Park, J. Lee, D. Shin, and S. Park "Luminance uniformity of large-area OLEDs with an auxiliary metal electrode," J. Display Technol., Vol. 5, pp. 306-311, (2009). https://doi.org/10.1109/JDT.2009.2018130