於本論文中，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。首先，我們先對傳統畫素驅動電路(2T1C)與已發表之電壓補償電路(5T2C)進行模擬與討論。根據電路模擬的結果，傳統畫素架構易受不同薄膜電晶體特性的影響而造成有機發光二極體面板的不均勻，且有機發光二極體電流的平均錯誤率高達37.7 %。相對地，模擬結果顯示已發表之電壓補償電路(5T2C)藉由特定的補償方法可有效地減少有機發光二極體面板的不均勻性，其有機發光二極體電流的平均錯誤率可降低至0.7 %。
為了要克服傳統畫素架構之不均勻性的問題，我們提出了一個新的電壓補償主動有機發光二極體之畫素電路與兩個修正的畫素電路，分別為 6T2C畫素電路,5T2C畫素電路和4T2C畫素電路。6T2C畫素電路為初步基礎的設計，模擬結果顯示其有機發光二極體電流的平均錯誤率僅3.27 %，因此可以使有機發光二極體電流與驅動電晶體(driving TFT)之臨界電壓(threshold voltage)幾乎無關。為了要改善6T2C畫素電路之開口率(aperture ratio)問題，藉由改變電路控制訊號我們可以去掉其中一顆電晶體使其成為5T2C畫素電路。模擬結果顯示其有機發光二極體電流的平均錯誤率僅3.79 %，因此本畫素電路可以成功地補償驅動電晶體之臨界電壓變異。此外，上述兩個電路(6T2C,5T2C)都可以將原來補償的時間由50 μs縮短至13 μs，這將有助於高解析度面板之發展。
為了要改善5T2C畫素電路有機發光二極體電流的平均錯誤率與增加其開口率，我們又去掉一顆電晶體而提出了4T2C畫素電路。模擬結果顯示其有機發光二極體電流的平均錯誤率可降低至0.8 %，因此4T2C畫素電路有效地改善了由多晶矽薄膜電晶體特性不同所造成的不同臨界電壓之問題也改善了主動有機發光二極體面板的不均勻性。
總而言之，本篇論文所提出的三個補償畫素電路均可有效地改善驅動電晶體不同臨界電壓之問題。與傳統的畫素結構(2T1C)相比，這些補償畫素電路都可以大幅提升面板的均勻性，因此在未來之主動有機發光二極體面板應用上極具潛力。

In this thesis, driving circuits for active-matrix-organic light-emitting-diode (AMOLED) displays that use low-temperature polycrystalline silicon thin-film transistors (LTPS-TFTs) with a voltage programming method have been investigated.
At first, conventional 2T1C circuit and published 5T2C pixel circuit proposed by J. H. Jung et al. are simulated and discussed. Simulation results show that conventional 2T1C pixel circuit has high non-uniformity due to the various characteristics of TFTs. The average error rate of the OLED current is up to 37.7 %. As for published 5T2C pixel circuit, it has very low non-uniformity of AMOLED displays by the special compensating method. The average error rate of the OLED current is only 0.7 %.
In order to overcome the non-uniformity problem of conventional 2T1C circuit, we propose a new voltage programming AMOLED pixel design and two modified pixel circuits, which are composed of 6T2C, 5T2C, and 4T2C. The 6T2C circuit is the basic design in the beginning and the simulation result shows the average error rate of the OLED current is about 3.27% in the 6T2C circuit. Consequently, it is apparently that the OLED current is independent of the variation of threshold voltage. In order to improve the aperture ratio of 6T2C circuit, the 5T2C circuit is the first modified design by eliminate a TFT. It shows that the average error rate of the OLED current is only 3.79 % in the 5T2C pixel circuit. As a result, it is apparently that the 5T2C circuit can successfully compensate for the threshold voltage variation of driving TFT. Furthermore, both 6T2C and 5T2C pixel circuits can also shorten the compensating time from 50 μs to 13 μs, which is more suitable for the development of high-resolution displays. In order to improve the error rate of OLED current and the aperture ratio of 5T2C circuit, the 4T2C circuit is the second modified design by eliminate another TFT. It shows that the average error rate of the OLED current is only 0.8 %. Therefore, the simulation results demonstrate that the 4T2C circuit has high immunity to the threshold voltage deviation of poly-Si TFT characteristics and improve the current non-uniformity for AMOLED.
In conclusion, these three proposed pixel circuits all successfully compensate for the threshold voltage variation of driving TFT and improve the current non-uniformity for AMOLED compared with conventional pixel circuit. Therefore, they could be the promising candidates for the AMOLED panel application in the future.

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