數位相機作為影像工具在各個領域中扮演著重要角色，然而在色彩準確度方面仍存在挑戰。本研究旨在探討搭載IMX250MYR偏振感測器的偏光相機在色彩準確度方面的表現，並與一般彩色相機進行比較。本研究通過實驗設計，分析了兩種相機在非偏振光源和偏振光源下拍攝的影像，並著重研究了色彩特性和線性偏振度之間的關聯性。
在實驗一中，我們比較了不同的色彩映射方法，結果顯示3×11擴展矩陣具有最佳效果。然而，使用偏光片獲取的正交偏光影像可能對色彩量測準確性產生影響，需要權衡色差結果和消除鏡面反射、眩光效果之間的關係。
在實驗二中，我們研究了偏振光源對相機色彩特性的影響。結果顯示，偏振光源的加入導致不同偏振角度的彩色影像產生不同的色度偏移趨勢。具體而言，90°和0°彩色影像展現了相反的色度偏移趨勢，而45°和135°彩色影像則具有相似的色度偏移趨勢但幅度較小。此外，我們也探討了線性偏振度與色彩資訊的關聯性，結果顯示明度資訊與線性偏振度較為相關，而彩度資訊則不相關。
在實驗三中，我們進一步研究了高光澤度樣本對相機色彩特性的影響。結果顯示，由於自製光澤度測試樣本的不均勻色塊影響，兩個光澤度樣本幾乎沒有保留偏振光源提供的線性偏振狀態。此外，我們觀察到物體表面狀態和光源變化對線性偏振度變化和色度偏移具有相關性。
綜合研究結果，本研究提供了對偏光相機色彩特性的深入研究和相關討論。實驗結果顯示偏振光源、色彩映射方法和樣本差異等因素對相機色彩的影響，並探討了線性偏振度和色彩資訊之間的關聯性。這些結果對於偏光攝影技術的應用和相關領域的研究可能有所貢獻。

This study investigated the color accuracy performance of a polarization camera equipped with the IMX250MYR polarization sensor and compared it with a conventional color camera. The experiment examined images captured under non-polarized and polarized light sources, and focused on the relationship between color characteristics and linear polarization degree.
In experiment 1, the results show that the 3×11 matrix performed the best after color mapping. However, using a polarizer to capture cross polarized images may affect color measurement accuracy, and may require a trade-off between color differences and the elimination of specular reflection as well as glare effects.
In experiment 2, the introduction of polarized light sources leaded to different chromaticity shifts in images under different polarization angles. Specifically, the 90° and 0° color images exhibit opposite chromaticity shift trends, while the 45° and 135° color images show similar but smaller shifts. Luminance information was found to be more related to linear polarization degree, while chromaticity information shows less correlation.
In experiment 3, the impact of high glossiness samples on camera color characteristics was examined. Due to the uneven color blocks of the self-made glossiness test samples, the linear polarization state provided by the polarized light source was difficult to retain in both glossiness samples. The surface condition of objects and changes in light sources were observed to be correlated with variations in linear polarization degree and chromaticity shifts.
In conclusion, this study provides insights into the color characteristics of polarization cameras. The findings contribute to the understanding of the influence of polarized light sources, color mapping methods, and sample variations on camera color accuracy.

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