增加薄膜液晶顯示器源極驅動IC有效位元之研究

The study of increase effective bits for the TFT LCD source driver

徐錦鴻(Chin-Hung Hsu)

指導教授 ： 陳淳杰

中原大學/工學院/電子工程研究所/碩士(2006年)

https://doi.org/10.6840/cycu200600530

摘要

在高畫質、低輻射及低消耗功率的訴求之下，在眾多的顯示器種類中，薄膜液晶顯示器已成為現今顯示器之主流，稱霸數十年的傳統陰極管顯示器，其佔有率正急速下降中。
在薄膜液晶顯示器的發展趨勢中可以看的出來，消費者對於液晶顯示器有幾項主要之要求：尺寸越來越大；目前最大之液晶電視已達到100寸。解析度越來越高；目前液晶電視解析度可達1920 x 1080。畫質越來越優異；在各大面板廠不斷的改良之下，亮度、對比的提高，液晶反應速率的提升，色彩數的增加，已讓液晶顯示器的品質媲美甚至多項超越傳統陰極管顯示器。然而這些進步卻是建立在價格越來越低的基礎上，才能形成今日薄膜液晶顯示器的主流地位。
由於源極驅動IC提供TFT LCD輸入來源，因此主導著最後液晶面板畫質與色彩數的表現，此外，由於一塊液晶面板上需要數顆的源極驅動IC來驅動整塊面板，由此可知源極驅動IC也是整個驅動系統中成本最高的元件，因此各大驅動IC廠莫不積極的著墨於源極驅動IC的改良，這也就是我選擇源極驅動IC為我研究標的的理由。
本篇論文主要是在歐姆定律為基礎上，讓源極驅動IC在保有價格的競爭優勢情況下，提供更多之輸出電壓，以達到提高顯示色彩數之目的。如使用六位元之源極驅動IC，利用伽馬補償電壓之變換，進而達到超過六十四種輸出電壓之效果，而從研究的結果中，也印證了利用伽馬電壓控制法可有效的產生出額外的電壓，達成增加驅動IC有效位元的目的，符合了當初的研究目標。

關鍵字

伽馬補償 ； 薄膜液晶顯示器 ； 伽馬電壓控制法 ； 圖場率控制 ； 源極驅動IC ； 電阻串

並列摘要

Under the request of high display quality, low EMI, and low power consumption, TFT LCD has become the main stream of displays. The market share of CRT, was the top 1, is dropping rapidly in past few years.
From the development trend of TFT LCD, we can find some major requests to TFT LCD from consumers listed as follows.
1.Larger panel size. The largest LCD TV size is 100 inches.
2.Higher resolutions. The resolution of high end LCD TV is 1920 x 1080.
3.Better display quality. Under the TFT makers continue improve, TFT LCD can provide high brightness, high contract, high response time, and more color depth.
From the above view of points, we know that TFT LCD provides more advantages than CRT. Furthermore, TFT LCD provides lower price than before. That is the reason why TFT LCD has become the main stream of displays now.
Source driver is the input of TFT LCD. It controls the display performance and color depth of TFT LCD. In addition, a TFT LCD panel needs several pieces of source driver to drive the panel. It shares most cost in the driving system. Thus all the driver IC design houses focus on the improvement of source driver. That is also the reason why I chosen source driver for my research target.
The purpose of this dissertation is to increase the output resolution of source driver and gain more color depth by Ohm’s law. Meanwhile, this improvement must keep the cost competitively. For example, if we use 6 bit source driver, we can get more than 64 voltages by gamma voltage control. From the result of this research, it has been proved that we can increase effective bits for the TFT LCD driver by Gamma Voltage Control. This answers the purpose of the study.

並列關鍵字

TFT LCD ； Gamma Voltage Control ； Gamma compensation ； R-string ； Source driver ； FRC（Frame Rate Control）

參考文獻

[12] 拓墣產業研究所，2006/03.

[1] Chun–Chin Chen, Chin-Hung Hsu, Nan-Ku Lu, and Ming-Lin Lee, “Color-Depth Improvement using Gamma Voltage Control,” International Symposium of Society for Information Display 2006 (SID 2006), June 4-9, 2006, San Francisco, USA.

[2] Chun–Chin Chen, Chin-Hung Hsu, Nan-Ku Lu, and Ming-Lin Lee, “Driving circuit and method for increasing effective bits of source drivers,” US patent pending.

[4] Kazuo Sekiya, Tokyo; Yuichi Shiraishi, Yamato, IBM Corporation., US patent 5059962, “Display system.”

[7] R. Jacob Baker, Harry W. Li, David E. Boyce. “CMOS Circuit Design, Layout, and Simulation.”