高效率白光有機發光二極體於照明運用並搭配光取出膜之研究

Abstract

以照明需求為前提，有機發光二極體的發光效率、電性和白光光色都是必要的需求，照明運用的OLED與顯示器運用的OLED元件，最大的差異就是發光面積的不同，若要增加發光面積勢必會遇到電性等問題。本論文第一部分以照明用途的白光OLED為出發點，開發適用於2 cm x 2.5 cm大發光面積基板的雙波段白光螢光OLED元件結構：使用主發光體MADN和NPB分別摻雜螢光客發光材料EY-53(橘黃光)和BUBD-1(天藍光)，另外配合p型摻雜的電洞傳輸層和n型的電子傳輸層製作於2 cm x 2.5 cm發光面積，在照明需求1000 nits下成功達到3.8 V的低操作電壓，生命半衰週期約為800小時。第二部分運用此2 cm x 2.5 cm大發光面積、低操作電壓元件結構，搭配外部光取出膜以增加效率並改善光色，相較於未貼附增亮膜的元件，在相同電流密度下貼附散射式(Diffuser)增亮膜元件總流明(Lumens)增加1.33倍，貼附微透鏡式(Microlens array)增亮膜元件軸向出光強度增加1.31倍，在1000 nits下功率效率分別達到24.6 lm/W和22.3 lm/W，，且CIEx,y座標分別為(0.39, 0.39)、(0.41, 0.40)，位於普朗克黑體輻射軌跡內。

As requirement of lighting application for Organic Light-Emitting Diode, the power efficiency, color purity of white and larger lighting area are reguired. In the first part of the thesis, we focus on developing OLED for lighting application through dichromatic fluorescence white OLED. By doping EY-53/ BUBD-1 in MADN/ NPB as yellow/ sk-blue emitter and coupling with p-HTL/ n-ETL, we successfully achieved low operation voltage 3.8 V, CIEx,y value of (0.43, 0.43) under the condition of 1000 nits with 2 cm x 2.5 cm lighting area and the lifetime (T50) is about 800 hours. In the second part, to enhance efficiency and pure the color quality, we tried to combine WOLED with light out-coupling films. The device with the light out-coupling film enhanced 1.33 times in total lumens for diffuser film and 1.31 times in the normal direction for Microlens array film under the same current density as compared with device without outcoupling film. Under condition of 1000 nits, the power efficiency are 24.6 lm/W and 22.3 lm/W, the CIEx,y value are (0.39, 0.39) and (0.41, 0.40) which are in the Planckisn Locus