Highly efficient phosphor-converted white organic light-emitting diodes with moderate microcavity and light-recycling filters.

نویسندگان

  • Sang-Hwan Cho
  • Jeong Rok Oh
  • Hoo Keun Park
  • Hyoung Kun Kim
  • Yong-Hee Lee
  • Jae-Gab Lee
  • Young Rag Do
چکیده

We demonstrate the combined effects of a microcavity structure and light-recycling filters (LRFs) on the forward electrical efficiency of phosphor-converted white organic light-emitting diodes (pc-WOLEDs). The introduction of a single pair of low- and high-index layers (SiO(2)/TiO(2)) improves the blue emission from blue OLED and the insertion of blue-passing and yellow-reflecting LRFs enhances the forward yellow emission from the YAG:Ce(3+) phosphors layers. The enhancement of the luminous efficacy of the forward white emission is 1.92 times that of a conventional pc-WOLED with color coordinates of (0.34, 0.34) and a correlated color temperature of about 4800 K.

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عنوان ژورنال:
  • Optics express

دوره 18 2  شماره 

صفحات  -

تاریخ انتشار 2010