近年來，有機發光二極體平面顯示器已在許多商品中呈現。由於它的色彩飽和度、輕量化、低功耗、反應時間快速以及高對比相較於液晶顯示器都優異許多，儼然成為下一世代顯示器的最佳選擇，在追求高畫面品質的當下，有機發光二極體顯示器私乎是更好的選擇。
在本論文中，研究補償低溫多晶矽薄膜電晶體之臨界電壓的飄移以及有機發光二極體之亮度衰退應用於有機發光二極體平面顯示器之畫素結構。由於LTPS-TFT製程的關係，導致LTPS-TFT產生特性上的差異，因此造成在玻璃面板上做整合積體電路時臨界電壓的不一致，進而影響整體畫面的不均勻。因此藉由本篇論文提出了新型的畫素電路來補償臨界電壓的差異以及回授電路技術來補償有機發光二極體亮度衰退的問題。其次針對OLED跨壓和亮度衰退的相關性，亦提出源極接法與汲極接法的二個補償電路來做比較。
首先，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(5T2C)，有效的補償臨界電壓的飄移以及OLED的衰退，模擬結果顯示有激電機發光二極體的平均電流錯誤率僅4%，相較於傳統的2T1C畫素結構(30%~70%)大幅度的下降，這將對於驅動電晶體之臨界電壓的影響性有顯著的降低。並且藉由回授結構(5T2C)來改善OLED的衰退，根據模擬的結果可以得知，當OLED臨界電壓因長時間使用而提高時，導通之電流仍然維持穩定，使得亮度可以維持，不會因為OLED跨壓提高而導致電流衰退。接下來提出一5T1C電路，目的在於討論OLED臨界電壓跟導通電流的相關性，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4~5%，對於OLED在電壓飄移之下電流的錯誤率也只有10%以下，大幅改善元件衰退所造成的影響。
總而言之，本論文中所提出的二個畫素驅動電路可有效補償低溫多晶矽薄膜電晶體以及有機發光二極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，相信是未來有機電機發光二極體顯示器之非常適合的畫素結構。

Since flat panel displays have the following traits: slim profile, light weight, low power consumption, wide viewing angle, full color, etc, they are essential for various applications. Among the numerous different flat panel displays, Organic Light Emitting Diode (OLED) display features high brightness, wide viewing angle, light weight, low power, and producing light by itself, the Display industry is paying particular attention to the OLED display.
In this thesis, voltage programming methods of driving circuits for active-matrix-organic light-emitting-diode (AMOLED) displays pixel structure that use low-temperature polycrystalline silicon thin-film transistors (LTPS-TFTs) have been investigated. This circuit technique has constructed a function that has no relation to the threshold voltage of the driving transistor; this is also the main concept of this thesis. The LTPS-TFT process by ELA enables the LTPS-TFT to produce the characteristic of the mutant problem, causing the threshold voltage variation in every single transistor to differ in the whole panel array. Therefore, in constructing this pixel function, we need to try to solve this problem.
A new pixel driving scheme and modified circuit to compensate for the threshold voltage shift and OLED degradation have been proposed, which are 5T2C and 5T1C structures, respectively. The 5T2C circuit is first designed to compensate for the threshold voltage shift of the driving TFT. The 5T2C circuit contains a special feedback scheme to sense OLED degradation. Subsequently, by the way of eliminating the relation of driving current and OLED voltage, a comparison is made of the source connect and drain connects for the pixel driving scheme in 5T1C. The simulation results show that 5T2C can successfully compensate the threshold voltage of driving TFT. Because the average error rate of the OLED current is about 4%. The 5T2C pixel circuit is designed to add a p-type TFT as a feedback loop; this can compensate for OLED degradation. The simulation results show that when the OLED voltage increased, the OLED current is also increased to compensate the degradation.
In conclusion, these two proposed pixel circuits successfully compensate for the threshold voltage variation of the driving TFT, and greatly improve the current uniformity for AMOLED. Therefore, the circuit scheme is a good candidate for future AMOLED panel applications.

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