Highly circularly polarized white light using a combination of white polymer light-emitting diode and wideband cholesteric liquid crystal reflector

被引：6

作者：

Lee, Hyun-Jung ^{[1
]}

Lee, Bo Ram ^{[1
]}

Choi, Suk-Won ^{[2
]}

Song, Myoung Hoon ^{[1
]}

机构：

[1] UNIST, Sch Mech & Adv Mat Engn, Low Dimens Carbon Mat Ctr, Ulsan 689805, South Korea

[2] Kyung Hee Univ, Dept Adv Mat Engn Informat & Elect, Yongin 446701, Gyeonggi Do, South Korea

来源：

OPTICS EXPRESS | 2012年 / 20卷 / 22期

关键词：

HIGH-EFFICIENCY; DEVICES; ELECTROLUMINESCENCE; EMISSION; POLY(N-VINYLCARBAZOLE); ELECTROPHOSPHORESCENCE; POLYFLUORENE; THRESHOLD; DYES; FILM;

D O I：

10.1364/OE.20.024472

中图分类号：

O43 [光学];

学科分类号：

070207 ; 0803 ;

摘要：

We present a simple and intriguing device that generates highly circularly polarized white light. It comprises white polymer light-emitting diodes (WPLEDs) attached to a wideband cholesteric liquid crystal (CLC) reflector with a wide photonic bandgap (PBG) covering the visible range. The degree of circular polarization realized is very high over the visible range. The wide PBG was realized by introducing a gradient in pitch of the cholesteric helix by controlling the twisting power within the CLC medium. WPLEDs fabricated using a ternary (red, green, and blue) fluorescent polymer blend with the same moiety showed a low turn-on voltage, high brightness, high efficiency, and good color stability. (C) 2012 Optical Society of America

引用

页码：24472 / 24481

页数：10

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