Displays with different primary sets were found to introduce perceived color mismatch between pairs that are computationally metameric and to affect the degree of observer metamerism. OLED display is becoming more and more popular than LCD display in different imaging systems. In this study, human observers used an LCD and eight OLED displays to match the color appearance of a D 70 white stimulus produced by a spectrally tunable LED device. It was found the chromaticities of the LCD display were significantly different from those of the OLED displays to achieve a match. When the colors were adjusted to have matched appearance, the chromaticities of the OLED displays were always shifted towards closer to the blackbody locus using the CIE 1931 Color Matching Functions (CMFs). The results also suggested that the CIE 2006 2° Color Matching Functions had the best performance.
Two methods to transform primary chromaticities and white point into primary tristimulus values are examined and compared. One method appears in numerous places in the literature; we refer to this as the "familiar" method, and provide a novel interpretation of it. The second is much less well-known and is referred to as the "unfamiliar" method. Necessary and sufficient conditions for computing primary tristimulus values from their chromaticities are identified; in brief, the triangle in the (x, y) chromaticity diagram must have non-zero area. The computational burdens for the methods were compared; the familiar method required slightly more arithmetical operations. Two problems with the familiar method were identified: high potential for rounding error and the inability to contend with a non-luminous primary. The unfamiliar method is less prone to rounding error, and is able to contend with primaries on the alychne. It is recommended that the unfamiliar method be preferred.