微顆粒散射膜對有機發光元件光學特性影響之研究

Abstract

有機發光元件不僅能作為平面顯示器的應用也可作為平面照明光源。在照明的用途中，電至光的轉換效率是其中一個重要的評斷標準。 本研究使用微顆粒散射膜，設法改善有機發光元件的出光耦合率，藉此提高電至光的轉換效率，並檢視微顆粒散射膜對有機發光元件光學特性的影響。低成本、製作簡單、不破壞元件電特性是使用微顆粒散射層主要的優勢。 在藍光與紅光的雙色光混色型白光有機發光元件中，使用不同濃度及厚度微顆粒散射膜，最佳的結果為外部量子效率增加了20%、正向cd/A增進了約22.6%、lm/W增進了約22.4%，與光學模擬預測的結果相較，趨勢一致。在元件的電激發光頻譜方面，使用微顆粒散射膜，具有不同視角下，色偏減少的優點。

Organic light emitting devices (OLED) have attracted wide interest due to their applications not only for flat panel displays but also for solid-state lighting. In lighting purposes, the electricity- to-light conversion ratio is one of the critical criteria. In our study, we use micro-particle diffuser films to improve the light out-coupling efficiency of OLEDs. Simple fabrication, low cost, and not affecting the electrical properties of OLEDs are the major superiority. Furthermore, we examine optical characteristics of OLEDs using micro-particle diffusers. In the two-component white OLEDs(blue+red), by adjusting different concentrations and thicknesses of micro-particle diffuser films, the external quantum efficiency can be enhanced by about 20%, the forward viewing cd/A can be enhanced by about 22.6%, and the lm/W can be enhanced by about 22.4%. The optical simulation results are qualitatively consistent with experimental results. In aspect to electroluminescent spectrum of OLED, after laminating with micro-particle diffuser films, it has the advantage of decreasing color shift for different viewing angles.