主動式矩陣有機發光二極體顯示器被視為下一世代極具發展潛力的顯示技術，近年來主要應用於可攜式裝置上，並逐漸發展大尺寸家用顯示器市場。顯示器亮度由流經有機發光二極體的電流大小所決定，此電流藉由薄膜電晶體和儲存電容所構成的畫素電路控制。然而採用不同製程的薄膜電晶體會因為製程因素而發生電子特性變異，或者是因為長時間操作而導致臨界電壓漂移等問題，且有機發光二極體材料在長時間操作下會老化而導致臨界電壓上升和發光效率下降，以及電源線內阻效應導致電壓下降等，以上因素皆會造成顯示器亮度不均勻，降低顯示品質。
為了增加顯示品質，本論文提出五個新式畫素補償電路，前三個畫素電路採用具有較高載子移動率和穩定性的低溫多晶矽薄膜電晶體作為背板材料，然而其因為製程因素所導致的電子特性變異會造成顯示器亮度不均勻的現象。本論文第一個畫素補償電路其架構為2T1C，驅動方法為同步式發光因此可適用於3D顯示器，此電路能夠補償驅動薄膜電晶體臨界電壓變異，並且藉由模擬結果驗證在所有灰階範圍內的相對電流誤差率小於3.4%，因此能夠提高OLED電流和亮度的穩定性。雖然第一個畫素電路架構簡單，但是在同一行畫素的外部電路中需要有一組開關進行電源線和資料線切換，因此電路成本較高，應用在實際面板上的可行性較低。本論文第二個畫素補償電路其架構為3T2C，採用目前主流的漸進式發光驅動方法，並且能夠補償驅動薄膜電晶體的臨界電壓變異，電路操作皆由畫素電路內之元件進行，因此能夠降低整體電路成本。由模擬結果可知當驅動薄膜電晶體的臨界電壓變異±0.5 V時，本電路的OLED電流相對誤差率在所有灰階範圍內小於2.54%。由p型薄膜電晶體組成的畫素電路，其OLED電流除了受到驅動薄膜電晶體臨界電壓變異所影響，也會受到電源線內阻效應影響。有鑑於此，本論文第三個畫素補償電路同樣採用漸進式發光驅動方法，架構同樣為3T2C，藉由模擬結果可知此電路能夠同時補償低溫多晶矽薄膜電晶體的臨界電壓和載子移動率變異，也可以改善電源線內阻效應所造成的影響，在所有灰階範圍內其相對電流誤差率分別為2.44%、6.37%和0.89%，達到高亮度均勻性的目標。
接下來提出兩個採用n型非晶相銦鎵鋅氧化物薄膜電晶體作為背板材料的新式畫素補償電路，因為其具有比低溫多晶矽薄膜電晶體更均勻的元件電子特性、較低之漏電流及較低的製造成本，因此較適合應用於大尺寸AMOLED顯示器。這兩個畫素電路的操作皆使用電流補償電壓驅動式，皆能夠補償薄膜電晶體的臨界電壓漂移，並且OLED電流不受有機發光二極體臨界電壓上升影響。本論文第四個畫素補償電路其架構為5T1C，而本論文所提出的第五個畫素補償電路，其架構為更精簡的3T1C。由模擬結果可得知當驅動薄膜電晶體的臨界電壓漂移±0.5 V時，這兩個畫素電路的電流相對誤差率在所有灰階範圍內分別小於3.98%和0.61%，並且當有機發光二極體臨界電壓上升1 V時，這兩個畫素電路的電流相對誤差率在所有灰階範圍內分別小於3.82%和4.16%，也能夠達到高亮度均勻性的目標。

Active-matrix organic light-emitting diode displays have many advantages, such as wide-viewing angle, fast response time and excellent color reproducibility. This thesis presents five compensation pixel circuits for use in AMOLED displays to solve the issues including deviations of electrical characteristics of thin-film transistors, such as low-temperature polycrystalline-silicon, amorphous indium-gallium-zinc-oxide technology, and OLED degradation as well as power line I-R drop. The first circuit is utilized of simple 2T1C structure for use in 3D Full HD displays, and it compensates for threshold voltage variation. Howerver, the external swith circuit increases the system costs. Although the second circuit compensates for threshold voltage variation without external swith circuit, it suffers from VDD I-R drop. The third circuit compensates for not only threshold voltage variation but also VDD I-R drop and mobility variation. The previous three circuits are voltage programming LTPS pixel circuits, and the following two a-IGZO pixel circuits are operated with current-biased voltage-programming method. Although the fourth circuit compensates for threshold voltage shift of the driving TFT and the OLED with simple operation, the structure 5T1C is more complex. The last circuit with simple 3T1C structure can also compensate for threshold voltage shift of the driving TFT and the OLED, but the uniformity of luminance would be affected by parasitic resistance and capacitance of SCAN line signals.

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