具有光學耦合層下發光微共振腔之有機發光元件模擬研究

Abstract

由於其可撓性、可彎曲性、耐衝擊性…等好處，OLED軟性顯示器在科技發展上越來越重要。但OLED出光效率低落一直是個待解決的問題，以前有許多方法包括減少淬熄效應、減少基板與空氣間的全反射效應以及減少波導模態…等。但這些方法之中有許多是會讓OLED元件失去軟性顯示器的特質，變成不可撓的元件。近來在Nature Photonics中有一篇改善OLED出光效率的論文既可兼顧軟性顯示器的特質也可增進OLED出光效率，其相當高的效率提升令我們想要探討其深入元件機制。 在本論文中， 我們仿照Nature Photonics論文中的元件結構，作了一系列的模擬計算。發現同結構下，我們所計算的發光效率增益只有1.455倍，不及其論文所提及的兩倍。此結果差異可能是改變元件結構所造成的電性提升，使得OLED發光效率額外增益許多，超出光學模擬可以解釋的範圍。

Due to their various features and merits, flexible OLED displays are becoming more and more important. Yet, the low optical out-coupling efficiency of OLED devices is still an issue. There are some solution like reducing the quench effect, reducing the total internal reflection between substrate and air, and reducing the waveguilde modes…etc. Yet, some of them will change the OLED flexible feature. Recently, page in Nature Photonics provides a method to improve the optical out-coupling efficiency and keeps the OLED flexible feature. Here, we want to investigate their mechanism by simulation. In this study, we based on their structures, we conducted a series of calculation. Our calculation indicates only a 1.455Xefficiency enhancement, much lower than their 2X enhancement. The discrepancy of the results may be due to improved electrical properties in their device structures, beyond the pure optical effects.