近年來，為了降低面板成本與提高大尺寸基板之均勻性，非晶矽薄膜電晶體及非晶相銦鎵鋅氧化物薄膜電晶體技術設計整合於主動式液晶顯示器已逐漸成為主流趨勢。然而，非晶矽薄膜電晶體及非晶相銦鎵鋅氧化物薄膜電晶體老化而產生臨界電壓飄移，進而影響閘極驅動電路及畫素電路的穩定性，造成面板顯示畫面失真。此外，主動式液晶顯示器搭配內嵌式觸控架構成為未來發展重點之一。然而，當顯示驅動訊號及觸控偵測同時操作時，顯示驅動訊號會經由面板之寄生電容造成觸控偵測訊號失真，此現象稱為顯示至觸控串擾，因此對於內嵌式觸控面板來說，解決顯示至觸控串擾已成為不可避免的議題。在主動式矩陣液晶顯示器技術中，藍相液晶相較於傳統液晶擁有較快的反應時間、不需配向層、視角廣等特色，因此被視為下一世代顯示器發展的重要技術。然而，藍相液晶之等效電容會隨著顯示器操作頻率上升而下降，此現象稱為高頻效應，進而造成藍相液晶跨壓改變，使顯示器產生錯誤的灰階亮度。
本論文提出二個新式非晶矽閘極驅動電路與一個新式非晶相銦鎵鋅氧化物藍相液晶畫素電路，並經由模擬及實際量測證明所提出電路之可行性。第一個電路為低漏電之閘極驅動電路，藉由四組重疊的時脈訊號及所設計之下拉電路，降低驅動點在電路產生輸出電壓時的漏電，進而使驅動薄膜電晶體維持較高的驅動能力。實際量測結果顯示，此電路之下拉電路相較於其他架構擁有較低的漏電確保電路的高驅動力，並可於高溫85 ℃且720小時操作後持續產生一致且穩定的輸出波形。第二個電路為適用於內嵌式觸控架構之新式閘極驅動電路，此電路能允許顯示器在任何一列暫停顯示操作並於一個畫面中執行數次觸控偵測，偵測結束後經由預充電架構繼續掃描。根據模擬結果，當預充電架構輸出電晶體之臨界電壓上升10 V時，電路在觸控偵測前與偵測後兩者之輸出波形充、放電達最高與最低電位所需時間的誤差分別為3.71 %與0.24 %。第三個電路為適用於高解析度與高更新頻率之藍相液晶畫素電路，此電路利用反相器架構產生一飽和區電流持續對藍相液晶等效電容充電，藉此減緩藍相液晶之高頻效應，最後在發光階段時關閉所有薄膜電晶體，避免藍相液晶等效電容漏電。模擬結果顯示，此電路在薄膜電晶體臨界電壓變化±1.5 V時，仍可產生穩定且線性的輸出曲線。

In recent years, hydrogenated amorphous silicon thin-film transistors (a-Si:H TFTs) and amorphous indium-gallium-zinc oxide thin-film transistors (a-IGZO TFTs) integrated in active-matrix liquid crystal displays (AMLCDs) have become the mainstream because of the low-cost fabrication and better uniformity over large-area substrates. However, the severe threshold voltage (VTH) shifts of a-Si:H TFTs and a-IGZO TFTs lead to the instability of gate driver and pixel circuits. Additionally, AMLCDs integrated with in-cell touch structure have attracted considerable attention. However, when the display driving and the touch sensing operate simultaneously, the display signals interfere in the sensed touch signals by parasitic capacitive coupling. This is defined as display-to-touch crosstalk (DTX). Consequently, solving the DTX has become an intensive issue for in-cell touch panels. Among AMLCD technologies, blue-phase liquid crystal (BPLC) is regarded as a next-generation technology for displays because it provides sub-millisecond response time, alignment-layer-free process, and wide viewing angle compared to LC. However, high operating frequency of the pixel circuit causes a decrease in the dielectric constant of BPLC. This phenomenon is called the high frequency effect. Therefore, the voltage variations across BPLC during the emission period lead to incorrect gray levels in displays.
This thesis proposes two a-Si:H gate driver circuits and an a-IGZO BPLC pixel circuit. The feasibility of the proposed circuits is verified through an HSPICE simulator and experimental results. The first gate driver circuit uses four-phase overlapping clock signals and the proposed pull-down circuit to reduce the leakage current when generating the output waveforms, maintaining high driving capability of driving TFT. Measurements-made during a high-temperature reliability test over 720 hours indicate that the output waveforms of the proposed circuit are highly stable. The second gate driver circuit is designed for use in in-cell touch panels. The proposed circuit pauses the operation of the display driving to support touch sensing operations several times per frame and then re-starts the display operation again. Simulation results indicate that the variations of rising time and falling time of output waveforms before and after touch sensing operation are 3.71% and 0.24%, respectively, when the VTH of re-charge TFT shifts by 10 V. The third circuit is a pixel circuit for high-resolution and high-frame-rate BPLC displays. With an inverter structure, the circuit generates saturation current to charge BPLC continuously, ameliorating the high frequency effect of BPLC. During the emission period, the circuit turns off all TFTs to avoid leakage current flowing into BPLC. The simulation results indicate that the proposed circuit achieves stable and uniform output characteristics even if the VTH of a-IGZO TFTs shifts by ±1.5 V.

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