由於主動矩陣有機發光二極體必須使用薄膜電晶體作為驅動與開關元件使用，所以在同一顯示器上薄膜電晶體的特性變異便會直接影響到主動矩陣有機發光二極體的顯示品質。除了薄膜電晶體以外，有機發光二極體本身的材料特性亦會影響到主動矩陣有機發光二極體的顯示品質。在長時間的操作下，會使得有機發光二極體出現跨壓上升與發光效率下降的問題。跨壓上升會影響電路操作，發光效率下降則會使亮度降低。
本論文針對上述問題提出三個新式畫素補償電路，用以提升主動矩陣有機發光二極體的顯示品質。第一個畫素電路架構為5T1C，能夠同時補償薄膜電晶體與有機發光二極體的材料變異。第二個電路則是保持畫素內為2T1C架構以維持顯示器的開口率，並利用外部電路來補償薄膜電晶體的材料變異。第三個電路則是綜合前兩個電路的特色，畫素內為3T1C並配合外部電路，以同時補償薄膜電晶體與有機發光二極體的材料變異。這個電路不僅可以大幅提升顯示的均勻性，亦可以提高面板開口率使亮度上升。所以本論文所提出的三個電路都有各自的特色，並且相當具有應用價值。

Thin film transistor is used as driving and switching component for Active matrix organic light emitting diode (AMOLED). Therefore, the threshold voltage variations of TFT will influence the display quality of AMOLED. Besides VTH variations of TFT, the degradation of OLED is also a main issue for AMOLED. After long time operation, the voltage drop of OLED will increase and the emitting efficiency will decrease. The increase of voltage drop affects the driving current, and the decrease of emitting efficiency reduces the brightness of displays.
In this work, three new pixel circuits are proposed to improve the display quality of AMOLED. The structure of the first circuit is 5T1C. This circuit will compensate VTH variations of TFT and degradation of the OLED with feedback structure successfully. The second circuit can compensate the VTH variations, and keep the conventional 2T1C structure in each pixel. The third 3T1C circuit can compensate VTH variations of TFT and degradation of the OLED. The proposed circuits have their own characteristic and contributions for AMOLED application in the future.

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