Color, complementary visible wavelengths

The success of separation of colored compounds is usually monitored visually. Such compounds absorb a particular portion of the polychromatic (white) light in the visible wavelength range. The remaining radiation (complementary radiation) is reflected and detected by the eye it determines the color of the substance zone. Table 1 correlates the wavelengths, colors and complementary colors. 

Color fatigue, or afterimage, is a retina and brain phenomenon in which intense continued observation of a certain visible wavelength will result in brain interpretation of the complementary color when the viewer looks at a white paper. 

Each color has a complementary color. For example, green and red are complementary colors. A mixture of complementary colors absorbs all visible wavelengths and appears black. Figure 22.15 shows these relationships on an artist s color wheel, where complementary colors appear as wedges opposite each other. 

For reference, the approximate wavelengths and complementary colors to the principal colors of the visible spectrum are given in Table 11-1. 

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