We use Fourier-plane imaging microscopy (FIM) to determine the transition-dipole-moment orientation in doped organic emissive thin films. The use of FIM enables precise, sensitive, and rapid measurement of dipole orientation in the emission layer of an organic light-emitting device (OLED). An optical model of a stratified birefringent multilayer is introduced for interpreting results obtained by FIM. Using the model, we determine the average orientation of transition-dipole-moment vectors of three phosphorescent dopant emitters. The dipole alignment measured by FIM quantitatively explains the difference in OLED efficiencies using these archetype dopant molecules. FIM provides a nondestructive tool to measure and ultimately improve the outcoupling efficiency of OLEDs and other light-emitting devices.

中文翻译：

---

使用傅里叶平面成像显微镜确定有机发光器件中的跃迁偶极矩方向

我们使用傅立叶平面成像显微镜（FIM）确定掺杂有机发光薄膜中的跃迁偶极矩方向。使用FIM可以精确，灵敏和快速地测量有机发光器件（OLED）的发射层中的偶极子方向。引入层状双折射多层光学模型以解释通过FIM获得的结果。使用该模型，我们确定了三个磷光掺杂剂发射极的跃迁偶极矩矢量的平均方向。通过FIM测量的偶极排列定量地解释了使用这些原型掺杂剂分子产生的OLED效率的差异。FIM提供了一种无损工具，可以测量并最终提高OLED和其他发光器件的输出耦合效率。