GB/T 7771-2008Measurement of special metamerism index - Change in illuminant (English PDF)

3.1

In observing the conditions prescribed, although spectral composition is different, but the same two color perception color stimulus. [GB/T 5698-2001 in

4.21]

Note. The specified viewing conditions refers to the observer and the field of view. For object color, it refers to the illumination light spectral power distribution.

3.2

Hereinafter the same color in the test conditions for the overall color difference between different spectrum.

Principle 4

If two different color samples in the visible spectral radiance distribution within the spectrum, and given the reference illumination and reference have the observer

With tristimulus values (X1 = X2, Y1 = Y2, Z1 = Z2), two color swatches of color is color metamerism.

For reference illumination and reference observer has two color swatches same tristimulus values, metamerism index is equal to the measured Mt

Two color difference value deltaE color swatch lighting body t calculated two different color that is a function of the reflectivity of the sample in a given illumination and a given color

It has the same tristimulus values under the conditions of the viewer, changing its color illumination larger metamerism effects are more obvious. This standard

Mt can quantify the degree of metamerism effects.

5.1

generally use International Commission on Illumination CIE standard illuminant D65 as the reference illuminant. Such as the use of other illumination should be described.

5.2

using CIE standard illuminant A body is a test or other lighting illumination.

5.3

Use of GB/T 3979-2008 specified in CIE1964 standard colorimetric observer.

6.1

color samples ready to perform according to GB/T 6688-2008 5.2.1 provisions.