Enhanced outcoupling in down-conversion white organic light-emitting diodes using imprinted microlens array films with breath figure patterns

• Published in: Science and technology of advanced materials Vol. 20; no. 1; pp. 35 - 41
• Main Authors: Han, Joo Won, Joo, Chul Woong, Lee, Jonghee, Lee, Dong Jin, Kang, Jisoo, Yu, Seunggun, Sung, Woo Jin, Cho, Nam Sung, Kim, Yong Hyun
• Format: Journal Article
• Language: English
• Published: United States Taylor & Francis 31.12.2019; Taylor & Francis Ltd; Taylor & Francis Group
• Subjects: 201 Electronics / Semiconductor / TCOs; 204 Optics / Optical applications, organic light-emitting diodes; 40 Optical, magnetic and electronic device materials; Arrays; down-conversion; Efficiency; Energy conversion efficiency; Light emitting diodes; light extraction; Microlenses; Optical, Magnetic and Electronic Device Materials; Organic light emitting diodes; outcoupling structures; Power efficiency; Quantum efficiency; Substrates; White light; white OLED; light extraction; Organic light-emitting diodes; white OLED; 40 Optical, magnetic and electronic device materials; down-conversion; 201 Electronics / Semiconductor / TCOs; 204 Optics / Optical applications, organic light-emitting diodes; outcoupling structures
• ISSN: 1468-6996; 1878-5514
• DOI: 10.1080/14686996.2018.1551040

We demonstrate high-performance down-conversion microlens array (DC-MLA) films for white organic light-emitting diodes (OLEDs). The DC-MLA films are readily fabricated by an imprinting method based on breath figure patterns, which are directly formed on the polymer substrate with a novel concept. The DC-MLA films result in high-quality white light as well as enhanced light outcoupling efficiency for white OLEDs. The external quantum efficiency and power efficiency of OLEDs with DC-MLA films are increased by a factor of 1.35 and 1.86, respectively, compared to OLEDs without outcoupling films. Moreover, the white OLEDs with DC-MLA films achieve a high color-rendering index of 84.3. It is anticipated that the novel DC-MLA films fabricated by the simple imprinting process with breath figure patterns can contribute to the development of efficient white OLEDs.