Trichromatic vision

Gilad, Y., Wiebe, V., Przeworski, M., Lancet, D and Paabo, S. (2004) Loss of olfactory receptor genes coincides with the acquistion of full trichromatic vision in primates. PloS Biology, 2, 120-125. 

Figure 5.5.9-3 shows both the individual functional spectra of long-wavelength trichromatic vision, and the nonfunctional dipole-molecular spectra of the same molecules, in caricature on a linear relative ordinate versus wavelength. This technique allows the information of the figure to be interpreted more easily. However, note that most of the actual data from the laboratory involves a logarithmic ordinate. The ultraviolet spectrum related to R(5) has been omitted for convenience on this graph. 

Figure 5.5.9-3 Caricature of the individual S-, M- L-spectral components of functional importance in long wavelength trichromatic vision combined with the spectrum related to dipole-molecular absorption (solid line). The vertical scale is linear and normalized. The width of the three chromatic spectra are shown at one fourth of their functional width as reported for the human eye. The dipole-molecular spectrum is shown at normal width. See text.

Color and Color Separation. In 1860,James Clerk MaxweU discovered that all visible colors could be matched by appropriate combinations of three primary colors, red, green, and blue (RGB). His experiment involved mixtures of colored lights added together to produce other colors or white light. This additive color is weU represented by the primaries RGB. Indeed, human color vision is trichromatic, ie, human visual response approximates receptors for the colors recognized as red, green, and blue (see Color). 

About 8% of males and less than 1% of females are born with defective color vision. As was discussed earlier, a person with normal color vision—the trichromat— has three kinds of color-sensitive cones red-, green-, and blue-sensitive cones. Dichromatism is when only two colors are perceptible and one color is difficult to recognize. 

The majority of persons, amounting to 92 per cent in the case of men, are trichromats, meaning that they have normal colour vision. When matching two or more shades with each other they make use of the three primaries. Between 2 and 3 per cent of men are dichromats because their eyes respond to only two primaries and their capacity to discriminate is less acute than that of the trichromats. 

Because cone vision is trichromatic, it means a suitable mixture of red, green and blue primary lights, as would be expected from a three-receptor system, can... 

Figure 3.6 Thomas Young (1773-1829), who laid the foundation of the wave theory of light and proposed the trichromatic theory of color vision. (Published with permission from the Deutsches Museum, Munich.)...

The first scientist to suggest the trichromatic theory of color vision, Thomas Young, laid the foundation for the wave theory of light, stating that when a body becomes luminous it sends out waves of particular amplitude and wavelength. He noted that the length of these waves determines their color in much the same... 

FIGURE 2 The graphics of the signal/noise function dependence fiom the earth surface energy illuniination for insects with different vision types a) monochrome, b) dichrome, c) trichromatic. 

FIGURE 3 The dependence graphics from the altitude h, of the useful signal producing by the optical emission selective sources (H-halogen tube, X-xenon lamp, T- tung sten lamp at T=1500 K, x=4m) in the insect s visual organ with the different vision types a) monochrome b) dichrome c) trichromatic. 

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