Organic light-emitting diodes require efficient and inexpensive light extraction methods for applications toward lighting and displays. Here, a facile and effective method for fabricating random organic microstructures for efficient light extraction from blue OLEDs is presented. Simple drop casting of a TCTA and B4PyMPM mixed solution followed by UV curing results in films with irregular-shaped microstructures (DACMs), ideal for light extraction without diffraction patterns. An external quantum efficiency (EQE) of 44.3% is realized by attaching DACMs formed on a polymer film to a blue phosphorescent OLED. The efficiency is improved by 35% compared to a planar device without the light extraction layer, greater than the 22% improvement obtained by using hemispherical-shaped microlens arrays. The method is useful for OLED lighting and potentially in displays because of the simple fabrication method that is applicable to a large area on rigid or flexible substrates, the low material cost, the insolubility of the microstructure in alkyl halide solvents such as chloroform, and the controllability of the structure through the solution process. Furthermore, we fully discuss on the EQE, enhancement ratio and the efficiency of light extraction structure (ELOS). We show that enhancement ratio and ELOS should be obtained using the optimized device structure as the reference device to be useful indicators for the effectiveness of a light extraction structure.

有机发光二极管需要高效且廉价的光提取方法以用于照明和显示器。在这里，提出了一种简便有效的方法，用于制造随机的有机微结构，以从蓝色OLED高效提取光。简单滴铸TCTA和B4PyMPM混合溶液，然后进行UV固化，可得到具有不规则形状的微结构（DACM）的薄膜，非常适合没有衍射图样的光提取。通过将在聚合物膜上形成的DACM附着到蓝色磷光OLED上，可以实现44.3％的外部量子效率（EQE）。与没有光提取层的平面器件相比，效率提高了35％，大于使用半球形微透镜阵列获得的22％的提高。该方法可用于OLED照明，并可能用于显示器，因为其简单的制造方法适用于刚性或柔性基板上的大面积区域，材料成本低，微结构在卤代烷溶剂如氯仿中的不溶性以及通过求解过程可以控制结构。此外，我们充分讨论了EQE，增强比和光提取结构（ELOS）的效率。我们表明，应使用优化的器件结构作为参考器件来获得增强率和ELOS，以作为光提取结构有效性的有用指标。微观结构在卤代烷溶剂（如氯仿）中的不溶性，以及溶液过程中结构的可控性。此外，我们充分讨论了EQE，增强比和光提取结构（ELOS）的效率。我们表明，应使用优化的器件结构作为参考器件来获得增强率和ELOS，以作为光提取结构有效性的有用指标。微观结构在卤代烷溶剂（如氯仿）中的不溶性，以及溶液过程中结构的可控性。此外，我们充分讨论了EQE，增强比和光提取结构（ELOS）的效率。我们表明，应使用优化的器件结构作为参考器件来获得增强率和ELOS，以作为光提取结构有效性的有用指标。