由於平面顯示器具有輕、薄、低功耗、廣視角及全彩化之特點，因此在應用上都具有相當大的潛力。在眾多不同種類的平面顯示器中，有機電激發光二極體顯示器因為具備有高亮度、視角廣、體積薄、省電、自發光..等優點，所以將會有大量的焦點集中在有機電激發光二極體顯示器上。
在本論文中，我們探討以低溫多晶矽薄膜電晶體(LTPS-TFTs)驅動之主動有機發光二極體(AMOLEDs)電壓補償畫素電路。相較於非晶矽薄膜電晶體，低溫多晶矽薄膜電晶體(LTPS-TFTs)擁有較好的電流驅動能力及較佳的可靠度，並且可以用來整合畫素電路及週邊的驅動電路於同一塊玻璃基板上，但是由於LTPS-TFT製程的關係，導致LTPS-TFT產生特性上的差異，因此藉由本篇論文提出了新型的驅動電路來補償臨界電壓的差異、IR-Drop的問題。
首先，先對傳統畫素驅動電路(2T1C)進行模擬與結果討論，根據模擬結果，傳統驅動電路容易受到不同元件特性的影響，造成傳統畫素驅動電路之電流的不穩定。為了克服傳統驅動電路的不穩定性，因此提出了一個新的電壓驅動之主動式有機電激發光二極體的補償電路，以及經過改良並提升開口率的兩個驅動電路，分別是5T2C畫素電路，4T2C、3T1C畫素電路。5T2C為最初設計的電路，模擬結果顯示有激電機發光二極體的平均電流錯誤率僅1.54%，對於Power line之IR-Drop達到1V的影響也僅是大約15%，這將對於驅動電晶體之臨界電壓以及IR-Drop的影響性有顯著的降低。後來藉由刪除5T2C畫素電路之一顆電晶體來提升開口率成為4T2C的驅動電路可達到提昇面板亮度的目，根據模擬的結果可以得知，有激電機發光二極體的平均電流錯誤率僅1.53%，對於Power line之IR-Drop達到1V的影響也僅是大約15%，此改良電路成功地補償臨界電壓及IR-Drop的問題。接下來針對4T2C來作改良，目的在於使開口率提升並使有機電激發光二極體平均電流之錯誤率能有所下降，因此去掉一顆電晶體、一個電容成為3T1C驅動電路，這將大大提升開口率，依照模擬的結果，有激電機發光二極體的平均電流錯誤率為1.41%，對於Power line之IR-Drop達到1V的影響維持在15%以下。
總而言之，本論文中所提出的三個畫素驅動電路可有效補償低溫多晶矽薄膜電晶體所造成之元件特性的差異，同時明顯的提升有激電機發光二極體之電流的均勻性，對於未來主動式有機電激發光二極體應用極具潛力。

As a result of flat panel displays have the potential for slim profile, light weight, low power consumption, wide viewing angle, full color, etc. Therefore flat panel displays are essential for various applications. Among of numerous different flat panel displays, Organic Light Emitting Diode (OLED) display has some fingerprint as high brightness, wide viewing angle, light weight, low power, and producing light by itself, Display industry will pay attention to OLED display.
In this thesis, voltage programming method of driving circuits for active-matrix-organic light-emitting-diode (AMOLED) displays that use low-temperature polycrystalline silicon thin-film transistors (LTPS-TFTs) have been investigated. Contrasting to amorphous silicon (a-Si) TFTs, LTPS-TFTs are provide with the higher current driving capability and the better reliability, and used to implement pixel circuits and driving circuits on a single glass substrate. But LTPS-TFT process by ELA, enable LTPS-TFT to produce the mutant problem of the characteristic. Therefore, the new voltage programming method of pixel circuit has been proposed, in order to compensate issues on variation of the threshold voltage, and IR-Drop phenomenon.
First of all, conventional 2T1C pixel circuit is interpreted for simulation results and discussions. The simulation results show that output current of conventional 2T1C pixel circuit is instable owing to various characteristics in TFTs. A new pixel design and two modified to promote aperture ratio voltage programming pixel circuits have been proposed, which are 5T2C, 4T2C, and 3T1C, respectively. The 5T2C circuit is first designed, not only the simulation result shows the average error rate of the OLED current is about 1.54% but also the IR-Drop of power line downs to 1 V. result in error rate of the OLED current is about 15%, The circuit will substantially decrease the effects include the threshold voltage and IR-Drop. Subsequently, by way of eliminating a TFT of 5T2C pixel circuit that improve the aperture ratio to become 4T2C pixel circuit, Go a step further, the goal is reached to improve luminance of display. The simulation results show that 4T2C can successfully avoid the threshold voltage of driving TFT and IR-Drop of power line issues. Because the average error rate of the OLED current is about 1.53% and the IR-Drop of power line downs to 1 V. result in error rate of the OLED current is about 15%. Continuously, in order to improve aperture ratio and reduce the average error rate of the OLED current, the 4T2C pixel circuit is modified to cancel a TFT, and a capacitor, and form the 3T1C pixel circuit that can greatly increase aperture ratio. The simulation results show that the average error rate of the OLED current is about 1.41% and the IR-Drop of power line downs to 1 V. result in error rate of the OLED current is below 15%.
In conclusion, these three proposed pixel circuits all successfully compensate for characteristics variation of LTPS-TFT and the threshold voltage variation of driving TFT and improve the current uniformity for AMOLED greatly. Therefore, the circuit designs possess the potential for the AMOLED panel application in the future.

Chapter 1
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Chapter 2
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Chapter 3
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Chapter 4
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