本論文主要目的是在三原色液晶顯示器上以模擬方式進行三原色與四原色色彩轉換之研究。我們以矩陣切換法(matrix switching)為色彩轉換演算工具，在CIEXYZ色彩空間中進行三原色與四原色轉換。此外，為了驗證色彩轉換的正確性，我們利用空間混色法在三原色液晶顯示器進行色塊模擬比較，四原色色塊是由「田」字形的四原色子畫素所構成，每一子畫素是由顯示器最小畫素單元「紅綠藍條型子畫素」所構成。我們以色彩光譜儀測量三原色與四原色色塊之色度值並做比較。模擬結果發現，三原色與四原色所構成之相同色塊經由色彩光譜儀所獲得之(x, y)色度值很接近，但在亮度表現上則差異頗大。為了提升四原色色塊的亮度，我們利用十四組灰階色塊的測量值，計算三原色原始色塊與四原色重建色塊之亮度比值的平均值當作重建色塊提高亮度的參數，以補償重建色塊亮度不足的問題。經過亮度補償後，重建色塊的亮度獲得提升，且色塊表現更接近原始色塊。

In this thesis, our major study is color conversion between three-primary and four-primary colors on the three-primary colors LCD by simulation. Matrix switching algorithm is the tool of color conversion processed in CIEXYZ color space. In order to confirm correctness of color conversion, we simulated and made comparisons of some color patterns on the LCD, which were spatial color mixing with the original three-primary colors and reconstructed four-primary colors, respectively. The pixel unit of four-primary colors was classical Bayer type, which sub-pixels were composed of original RGB stripe sub-pixels of LCD. We also used spectroradiometer to measure color characteristics of studied color patterns.

From experimental results, they show that the measured color values, (x, y) of the same color pattern respectively rendered by three-primary and four-primary colors are very close, but a significantly large luminance difference exists between them. To enhance the luminance of four-primary color patterns, we multiplied a factor in the measured spatially four-primary color spectrum. The value of multiple factor was the average ratio of luminance between three-primary and four-primary in fourteen gray patterns. After luminance compensation, the four-primary color patterns are more consistent with the original three-primary color patterns.

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