| In this dissertation, two types of polymer light-emitting devices (PLEDs) are presented. The first device is the polymer solution light-emitting device (SLED). Traditional PLEDs are solid thin-film devices, in which a luminescent polymer film is sandwiched between two electrodes. On application of the suitable voltage, the characteristic light is emitted. In this dissertation, we demonstrated a new type of device: polymer light emitting device (SLED). In the SLED, the active media is the polymer solution, which consists of a luminescent polymer and an organic solvent. The object of this work is to study the device mechanism and propose an equivalent circuit to model the SLED.; The second type of device is phosphorescent dye doped PLED. High efficiency organic light-emitting diodes have been demonstrated by using the phosphorescent dyes. However, in PLEDs, this strategy has not been successfully demonstrated. In this dissertation, efficiency as high as 13 cd/A of PLEDs doped by phosphorescent dyes were achieved. In addition, the device degradation mechanism is also studied. |
