A spectrum-adjusted white organic light-emitting diode for the optimization of luminous efficiency and color rendering index

Abstract

High luminous efficiency and high color rendering index (CRI) are both the foremost factors for white organic light-emitting diodes (WOLEDs) to serve as next generation solid-state lighting sources. In this paper, we show that both luminous efficiency and CRI can be improved by adjusting the green/red spectra of WOLEDs. With green emission spectra matching with the human photopic curve, the WOLEDs exhibit higher luminous efficiency and higher CRI. Theoretical calculation shows that by tuning the white emission spectra to maximally match with the human photopic curve, the luminous efficiency can be improved by 41.8% without altering the color coordinates, the color correlated temperature (CCT) and the external quantum efficiency (EQE) of the WOLEDs.

Keywords

Green Emission / Blue Emission / External Quantum Efficiency / Luminosity Function / Color Purity

References

[1] TyanY-S. Journal of Photonics for Energy, 2011, 1: 011009

[2] JiangY, LianJ, ChenS, KwokH-S. Organic Electronics, 2013, 14: 2001

[3] KamtekarK T, MonkmanA P, BryceM R. Advanced Materials, 2010, 22: 572

[4] GatherM C, KöhnenA, MeerholzK. Advanced Materials, 2011, 23: 233

[5] SeoJ H, LeeS J, SeoB M, MoonS J, LeeK H, ParkJ K, YoonS S, KimY K. Organic Electronics, 2010, 11: 1759

[6] WangQ, DingJ, MaD, ChengY, WangL, JingX, WangF. Advanced Functional Materia, 2009, 19: 84

[7] ChenS, QinW, ZhaoZ, TangB Z, KwokH-S. Journal of Materials Chemistry, 2012, 22: 13386

[8] ChangH-W, TienK-C, HsuM-H, HuangY-H, LinM-S, TsaiC-H, TsaiY-T, WuC-C. Journal of the Society for Information Display, 2011, 19: 196

[9] ChenS, KwokH S. Optics Express, 2010, 18: 37

[10] ChenS, ZhaoZ, TangB Z, KwokH-S. Organic Electronics, 2012, 13: 1996

[11] HumphreysC J. MRS Bulletin, 2008, 33: 459

[12] SchwartzG, ReinekeS, RosenowT C, WalzerK, LeoK. Advanced Functional Materia, 2009, 19: 1319

[13] SunY, GiebinkN C, KannoH, MaB, ThompasonM E, ForrestS R. Nature, 2006, 440: 908

[14] WalzerK, MaennigB, PfeifferM, LeoK. Chemical Reviews, 2007, 107: 1233

[15] MeerheimR, LüssemB, LeoKEfficiency and Stability of p-i-n Type Organic Light Emitting Diodes for Display and Lighting ApplicationsProceedings of the IEEE, 2009, 97: 1606

[16] ErdemT, NizamogluS, SunX W, DemirH V. Optics Express, 2010, 18: 340

[17] BassM, DeCusatisC, EnochJ, LakshminarayananV, LiG, MacDonaldC, MahajanV, StrylandE V. Handbook of Optics: Volume II, 2010, Third Edition

[18] ChenS, TanG, WongW -Y, KwokH -S. Advanced Functional Materials, 2011, 21: 3785

[19] ReinekeS, LindnerF, SchwartzG, SeidlerN, WalzerK, LüssemB, LeoK. Nature, 2009, 459: 234