Ho, Yu-HsuanYu-HsuanHoDING-WEI HUANGChang, Yung-TingYung-TingChangYe, Ya-HanYa-HanYeChu, Chih-WeiChih-WeiChuTian, Wei-ChengWei-ChengTianChen, Chin-TiChin-TiChenWei, Pei-KuenPei-KuenWei2018-09-102018-09-102012-01http://scholars.lib.ntu.edu.tw/handle/123456789/374189https://www.scopus.com/inward/record.uri?eid=2-s2.0-84863070648&doi=10.1364%2fOE.20.003005&partnerID=40&md5=fcdd812847d7891e958d3552495d1467The authors demonstrated an efficient color conversion layer (CCL) by using nanosphere arrays in down-converted white organic light-emitting diodes (WOLEDs). The introduced periodical nanospheres not only helped extract the confined light in devices, but also increased the effective light path to achieve high-efficiency color conversion. By applying a CCL with red phosphor on a 400-nm-period nanosphere array, we achieved 137% color conversion ratio for blue OLEDs, which was 2.68 times higher than conventional flat CCL. The resulting luminous efficiency of WOLEDs with patterned CCLs (20.97 cd/A, 1000 cd/m2) was two times higher than the efficiency of the flat device (10.26 cd/A, 1000 cd/m2). © 2012 Optical Society of America.[SDGs]SDG7Color; Efficiency; Light emission; Nanospheres; Organic light emitting diodes (OLED); Blue OLEDs; Color conversions; Light path; Luminous efficiency; Red phosphors; White organic light emitting diodes; Optoelectronic devices; nanosphere; article; chemistry; color; equipment; equipment design; illumination; instrumentation; nanotechnology; semiconductor; ultrastructure; Color; Equipment Design; Equipment Failure Analysis; Lighting; Nanospheres; Nanotechnology; Semiconductorsjournal article10.1364/OE.20.0030052-s2.0-84863070648WOS:000300499500107