對於主動式有機發光二極體顯示器而言，其畫素電路是由薄膜電晶體作為開關與驅動有機發光二極體的元件，然而隨著製程造成的誤差，例如：臨界電壓變異，以及有機發光二極體材料隨著長時間使用而老化的現象，元件特性會有所差異，使得面板本身產生亮度不均勻性以及亮度下降等情形，因而對於顯示品質造成影響。此外針對下發光方式而言，畫素內過多元件會造成開口率下降，進而影響發光效率。
本論文針對上述問題提出三個新式畫素補償電路，改善顯示器亮度均勻性與使用壽命。第一個電路架構為上發光方式5T2C畫素補償電路，上發光方式有較高的發光效率，透過與補償電路結合，能夠提高顯示器的顯示品質。第二個補償電路為第一個電路改良，4T1C畫素電路。第三個為下發光方式電路架構，其畫素內保持3T1C架構，利用外部補償電路補償薄膜電晶體與有機發光二極體元件的變異，畫素電路由精簡的元件數所組成，因此開口率會增加，使得發光效率上升。這三個電路提升顯示器亮度均勻性外，針對開口率的提高，對於發光效率有所助益，因此相當具有應用價值。

For active matrix organic light emitting diode (AMOLED), thin film transistors (TFTs) are used as driving and switching components in a pixel circuit. However, during fabricated process, the inevitable variations, such as threshold voltage variation, cause different driving currents leading to luminance non-uniformity. In addition, OLED degradation decreases the luminance over time, and excessive components in a pixel with bottom emission decrease aperture ratio.
In this work, three proposed pixel circuits ameliorate the quality of display. The first pixel circuit, composed of 5T2C with top emission, can improve luminance non-uniformity and degradation. The second pixel circuit, composed of 4T1C, is the improved circuit of the first one. The third circuit is that 3T1C in the pixel with bottom emission increase aperture ratio due to the compensation functionality achieved by the external driving circuit. These circuits have contributions for AMOLED application in the future.

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