From time immemorial people were worried about the question: why are the veins blue and the blood red? Experts took up this question, trying to find and justify the answer as accurately as possible. One of the first to notice this feature of the veins was surgeons.
Recently, a new theory was voiced in the press about this phenomenon, voiced by David Irwin from Sydney, who works at the University of Technology. In his opinion, the veins appear blue because they are so perceived by human vision, and also affects the characteristics of the blood and the light absorbed by the skin.
How does human vision perceive vein color?
And so, why the blue veins are to be found out. As you know, light waves are different, respectively, they have a similar length. The longest are red, and the shortest are purple, in the space between these two species are the other shades. The eyes begin to distinguish them when the waves come into view. Red waves are not very noticeable under the skin, because they are located at a distance of 5-10 millimeters, also because of their size they are not very prominent. Another reason was hemoglobin, which is in the blood, it is he who absorbs the red color.
Why are blue veins in my arms? In order to see the blue color, it is enough to shine on the hand with ordinary white light. In another light, for example blue, the veins will not be visible, since this light is easily reflected and scattered, without getting into the skin. With white, not tanned skin, blue veins are especially clearly visible.
How the sun affects color change
Also, why the blue veins are affected by ordinary sunlight. This happens because the tissues of the body absorb the red rays, while the blue ones, on the contrary, transmit. Light passes through the fabric a couple of times: inward and backward, during which time the tissues absorb the red color, while the blue remains intact.
The sun's rays move according to this principle:
- First, they enter the tissue, then pass through the skin, subcutaneous fat layer, vein walls and enter the venous blood.
- The sun contains the colors of the rainbow. Venous blood has colors: blue, red, yellow, on this basis, we can conclude that the blood reflects these colors, and absorbs the other four colors.
- The reflected three colors move in the reverse order: they pass through the veins, the fat layer and the tissue, and only then become visible to the eye.
The opinion of surgeons
The question of why the blue veins did not bypass the experts, they put forward a new theory. The fact is that the vessels are made up of white matter, which is as thick as oilcloth. Unlike arteries, which are deep under the skin and have dense walls, veins are transparent in color, so it is clearly visible that dark blood flows through them. When applying flowers, blood of dark cherry and veins themselves of white-gray shades, the result is a blue color.
The conclusion of German scientists
The most accurate justification why the blue veins were given by German experts. In addition to the words, they suggested facts that prove the appearance of color:
- this color perceives the brain;
- blood absorbs light;
- the skin itself reflects this color.
Most visible veins on white skin, because it practically does not absorb light. The color of different wavelengths gets on the skin, the red tint has the greatest length and therefore it is reflected by other vessels. Vision will perceive an image that is displayed from tissues. In the case when the vessels are near the surface of the skin, then almost all the blue color will absorb the blood, and the rest will be presented in the form of red.
In the case when the vessel is very deep, the light will be reflected before it reaches it, but the person will not see it at all. Practice shows that blood vessels display more red color, but the brain perceives it as purple and gives out information that it is supposedly blue.