Back in 1873, the famous British physicist D.K. Maxwell creates a general theory describing the processes occurring in an electromagnetic field. Waves were presented in the form of vortex disturbances. Subsequently, most of his theoretical calculations brilliantly confirmed. Currently, Maxwell's theories have expanded, as the fields themselves began to be considered from the point of view of the processes of quantum physics. At the same time, it was suggested that even visible light is nothing but one of the varieties of an electromagnetic wave. In 2009, this was finally proved by physicists (the magnetic component of the light flux was measured). Its main difference from other types of electromagnetic waves in the wavelength.
We are all accustomed to light, taking it for granted and rarely asking ourselves questions: what is the wavelength of light, what is it, etc. Even the Bible says that God created the light on the first day of creation. Indirectly, this indicates the importance of this for all living things. Visible light is radiation of an electromagnetic nature that can be directly detected by the eye. However, the organ of vision does not record the entire spectrum of the wave, but only a certain interval: the lower boundary is approximately 380 nm, and the upper 780 nm. Why "about"? Because each person has a different vision sensitivity and these limits are approximate. The full spectrum is so vast that the wavelength of light visible by a person is only 0.04%.
If two-dimensional coordinates are imagined, then the wavelength of light in nanometers will be plotted along the horizontal axis, and the vertical axis will indicate the sensitivity of the eyes. Accordingly, the beginning of the wave is at 780, and the end is at 380. The peak is reached at 555 nm. In the range of 10 nm - 380 nm is ultraviolet radiation, and infrared 780 nm - 1 mm. The total gap, amounting to the sum of ultraviolet, visible and infrared radiation, is the optical spectrum, although this does not mean that all of them can be seen with the naked eye. The wavelength of light is the most important characteristic for humans, since it is thanks to it that we can distinguish colors. The easiest way to catch the color shades at the peak of the wave (555 nm), but at the edges, in the areas of blue and red, is more difficult. Therefore, it is precisely when determining the derivative shades that people sometimes have disagreements, since the sensitivity of the eye receptors is different. Interestingly, 555 nm is the green spectrum that is most clearly distinguishable. Is it a coincidence that the grass and leaves are green? By the way, you can see some of the infrared radiation if you direct the camera of a mobile phone (or digital camera) to the LED of a working remote control from household appliances (TV, tuner, etc.).
The wavelength of red light corresponds to 700 nm, that is, almost from the very edge of the visible region. It follows that 10 conventional units of radiation in this range by the eye will be caught as one unit in green (555 nm). But the wavelength of yellow light, ranging from 560 nm to 590 nm, is located closer to the peak of the wave, so errors in determining shades by the human eye are less common.
In addition to various colors, one often encounters white in life. In fact, there is no white in the spectrum. It is obtained by mixing three basic colors. It is believed that if you combine all seven colors of the rainbow of the same intensity, you get a pure white color. At the same time, usually at least one of them prevails, which adds a certain shade. You can do it easier and mix only three colors - red, blue and green. The existence of ray-tube television screens with three electrodes (Red, Green, Blue) capable of displaying a white dot is direct evidence of this.