Communication of the person with an environment is carried out by means of sense organs: sight, hearing, touch, taste, sense of smell. These properties of a human body as information sources have great value in a life and activity of the person, its communication with world around.
The Greatest quantity of the information on the material environment (more than 80%) is connected with the visual sensations caused by physiological influence of reflected light waves (electromagnetic fluctuations) on visual receptors - an eye retina. The perception of colour of bodies is connected with various ability of subjects to absorb or reflect light beams.
Depending on selective ability distinguish Chromatic and achromatic surfaces. Tsvetovosprinimajushchie organs of vision of the person are sensitive to three primary colours - dark blue, green and red (trihromaticheskoe sight).
Physically colour define three categories:
1. In the dominating length of a wave I, defining colour tone. The eye is sensitive to rather small range of electromagnetic waves - in limits from 400 to 750 mmk that corresponds to a visible part of a spectrum from violet to the red. Reduction and increase in length of waves in the field of ultra-violet and infra-red radiations lies outside of our sight.
2. Colour purity R or its saturation defined in relation to white colour (pure tone or with an impurity white). It is expressed in percentage or in unit shares. The saturation of various spectral colours is perceived unequally. Red and dark blue are perceived more sated, than, for example, the yellow. For spectral colours colour purity is equal to unit, for white - to zero.
3. Relative svetlotoj colours or its factor of reflexion of the river This category is defined by the relation of the light stream reflected by a surface to all light stream falling on it,%. The factor of reflexion of various colour surfaces fluctuates from 0 (absolutely black body) to 100% (absolutely white body), practically from 4 to 90%: black colour - 4%; dark blue, and is dark-red-10; red - 13; dark grey - 15; green-16; red-orange - 23; orehovo-yellow - 25; beige - 38; terracotta - 40; blue - 45; flavovirent - 48; yellow - 55; white - 70-90%.