Polymer Dispersed Liquid Crystal for Enhanced Light Out-Coupling Efficiency of Organic Light Emitting Diodes
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초록
We investigated light extraction film based on polymer dispersed liquid crystal (PDLC) for application inorganic light emitting diodes (OLEDs). At least 30 seconds of direct UV irradiation process for curing PDLC filmon a bottom-emitting OLEDs was successfully achieved without damage on the intrinsic properties of the OLED. We demonstrated that high haze and transmittance can be tuned simultaneously by controlling the UV curingtime. By adding PDLC as an external layer without any additional treatment, the light scattering and extractionis increased. Consequently, a PDLC scattering film with 89.8% and 59.9 of total transmittance and hazerespectively, achieved about 16% of light intensity enhancement from integrating sphere measurement.
Abstract
We investigated light extraction film based on polymer dispersed liquid crystal (PDLC) for application inorganic light emitting diodes (OLEDs). At least 30 seconds of direct UV irradiation process for curing PDLC filmon a bottom-emitting OLEDs was successfully achieved without damage on the intrinsic properties of the OLED. We demonstrated that high haze and transmittance can be tuned simultaneously by controlling the UV curingtime. By adding PDLC as an external layer without any additional treatment, the light scattering and extractionis increased. Consequently, a PDLC scattering film with 89.8% and 59.9 of total transmittance and hazerespectively, achieved about 16% of light intensity enhancement from integrating sphere measurement.
참고문헌 (24)
- N. Thejo Kalyani, "Organic light emitting diodes: Energy saving lighting technology—A review", Renewable Sustainable Energy Rev, 16(5), pp.2696~2723 (2012)[DOI]
- T. -H. Han, "Extremely efficient flexible organic lightemitting diodes with modified graphene anode", Nat. Photonics, 6, pp.105~110 (2012)
- H. Sasabe, "Development of high performance OLEDs for general lighting", J. Mater. Chem. C, 1(9), pp.1699~1707 (2013)
- S. Kunic, "OLED technology and displays", Proc. ELMAR, pp.31~35 (2012)
- C. W. Tang, "Organic electroluminescent diodes", Appl. Phys. Lett, 51(12), pp.91915~ (1987)[DOI]
- R. Windisch, "Light-emittingdiodes with 31% external quantum efficiency by outcoupling of lateral waveguide modes", Appl. Phys. Lett, 74(16), pp.2256~2258 (1999)[DOI]
- K. Saxena, "A review on the light extraction techniques in organic electroluminescent devices", Optical Materials, 32(1), pp.221~233 (2009)[DOI]
- H. -W. Chang, "Organic light-emitting devices integrated with internal scattering layers for enhancing optical out-coupling", J. Soc. Inf. of Disp, 19(2), pp.196~204 (2011)[DOI]
- H. -W. Chang, "Nano-particle based scattering layers for optical efficiency enhancement of organic light-emitting diodes and organic solar cells", J. Appl. Phys, 113(20), pp.204~502 (2013)[DOI]
- N. K. Patel, "High-efficiency organic light-emitting diodes", IEEE J. Sel. Top. Quantum Electron, 8(2), pp.346~361 (2002)[DOI]
- S. Möller, "Improved light out-coupling in organic light emitting diodes employing ordered microlens arrays", J. Appl. Phys, 91(5), pp.3324~3327 (2002)[DOI]
- A. Kim, "Enhancement of out-coupling efficiency of flexible organic light-emitting diodes fabricated on an MLA-patterned parylene substrate", Organic Electronics, 71, pp.246~250 (2019)[DOI]
- Feng Li, "Enhanced light extraction from organic light-emitting devices by using microcontact printed silica colloidal crystals", Organic Electronics, 8(5), pp.635~639 (2007)[DOI]
- J. -W. Shin, "Random nanostructure scattering layer for suppression of microcavity effect and light extraction in OLEDs", Opt. Letters, 39(12), pp.3527~3530 (2007)
- J. Lim, "Enhanced out-coupling factor of microcavity organic lightemitting devices with irregular microlens array", Opt. Express, 14(14), pp.6564~6571 (2006)[DOI]
- Y. -J. Lee, "A high-extraction-efficiency nanopatterned organic light-emitting diode", Appl. Phys. Lett, 82(21), pp.3779~3781 (2003)[DOI]
- C.-H. Shin, "Nanoparticle scattering layer for improving light extraction efficiency of organic light emitting diodes", Opt. Express, 23(3), pp.A133~A139 (2015)[DOI]
- D. -Y. Zhou, "Light extraction enhancement from organic light-emitting diodes with randomly scattered surface fixture", Applied Surface Science, 314, pp.858~863 (2014)[DOI]
- J. Jiang, "Selective scattering polymer dispersed liquid crystal film for light enhancement of organic light emitting diode", Opt. Express, 25(4), pp.3327~3335 (2017)[DOI]
- J. W. Doane, "Polymer dispersed liquid crystals for display application", Mol. Cryst. Liquid Cryst, 165(1), pp.511~532 (1988)[DOI]
- S. C. Sharma, "A review of the electro-optical properties and their modification by radiation in polymerdispersed liquid crystals and thin films containing CdSe", ZnS quantum dots, 2010, pp.168(1-3), 5~15
- 김유라, "Optical properties and optimized conditions for polymer dispersed liquid crystal containing UV curable polymer and nematic liquid crystal", Current Applied Physics, 15(3), pp.292~297 (2015), 한국물리학회
- J. Lee, "Cavity effects on light extraction in organic light emitting devices", Appl. Phys. Lett, 92(3), pp.033303~ (2008)[DOI]
- H. -W. Chang, "Organic light-emitting devices integrated with internal scattering layers for enhancing optical out-coupling", J. SID, 19(2), pp.196~204 (2011)[DOI]