LCD色彩特性量度與色彩校正之通道串擾GOG 模型

CHANNEL-DEPENDENT GOG MODEL FOR COLORIMETRIC CHARACTERIZATION AND COLOR CORRECTION OF LCDS

傅志誠(Chih-Cheng Fu)

指導教授 ： 周俊賢

大同大學/電機資訊學院/通訊工程研究所/碩士(2008年)

摘要

近年來隨著科技的進步，LCD逐漸取代傳統CRT顯示器，成為市場上的主流顯示設備。GOG模型是依據CRT的顯示原理，有效描述其階調再現曲線，然而LCD的顯示特性不同，RGB各色彩通道常有相互影響的現象，即通道串擾情形，因此GOG模型並不適用於LCD。而在未來很有可能將色序法 (Color Sequential Display：CSD) 的顯示技術導入LCD，由於其組成結構，RGB通道串擾的情形更為嚴重。
本研究以GOG模型為基礎，考慮RGB通道相互作用和背光漏光的問題，提出能更精確描述顯示器的色彩特性模型，並且進行色彩校正。經實際量測LCD與CSD的色彩特性，驗證LCD與CSD皆有RGB通道串擾情形，且CSD比LCD更為嚴重，所以本篇論文主要是修正傳統GOG模型，建立通道串擾GOG模型，此模型的概念是依各通道與另外兩個通道輸入的數位訊號值來產生Gamma與gain的曲面函數，其Gamma與gain值不再是一個定值，會依另外兩個通道的強度而改變。經由實驗證明，本篇論文所提出之通道串擾GOG模型與傳統GOG模型的CIEDE2000色差比較結果，確實能更有效且更精確的評估傳統LCD與色序法顯示技術的色彩特性。
不同的顯示器，有不同的顯示特性，以至於相同影像在不同的顯示器上所看到的色彩可能不相同，所以我們希望，藉由我們提出的通道串擾GOG模型，能精確的評估色彩特性，並將色彩校正為sRGB國際色彩標準，以達到正確的色彩表現。

關鍵字

色彩校正 ； 伽瑪 ； 通道串擾 ； 色彩特性描述模型 ； 色序法

並列摘要

The CRT have to be replaced LCD which quickly becomes a common viewing device in recent years. The GOG model is based on the display structure of CRT, and can be accurate enough in describing the Tone Reproduction Curve (TRC). But the display characteristic is different between CRT and LCD. The channel interaction often occurs for each color channel and this is called channel dependent. So GOG model is not enough for characterizing LCD. In the future, the structure of Color Sequential Display (CSD) will substitute that of conventional one. Due to the differences in design and structure from LCD, the channel dependent condition to be more serious.
This research is based on GOG model. It considers the color channel interaction and the backlight leakage. In addition propose to a new model for more accurate colorimetric characterization and color correction. After measuring LCD and CSD colorimetric characterization for verifying the channel dependent, both of them have this condition but CSD is more serious than LCD. Therefore, in this thesis major objective for the improvement conventional GOG model and establish the Channel-dependent GOG model. The model theorem is modeling the variation of gains and gammas of the GOG models that characterize the TRCs of each color channel under different digital counts of the other two color channels. The gamma and gain is not constant again, the change for other two color channels intensity. Proved by way of the experiment that this thesis proposes the Channel-dependent GOG model and conventional GOG the model CIEDE2000 color difference comparison results, can truly more effective and more precise appraisal CSD and LCD monitor colorimetric characterization.
The different monitor has the different display characteristic. The same image is on the different monitor when see the color maybe is not same. Therefore our object, proposes the Channel-dependent GOG model by way of us, can be precise　estimation colorimetric characterization, and the color correction is the sRGB international color standard, achieves the monitor correct color performance.

並列關鍵字

color correction ； gamma ； crosstalk ； colorimetric characterization ； CSD

參考文獻

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