Microwave radiation is electromagnetic radiation, which consists of the following ranges: decimeter, centimeter and millimeter. Its wavelength ranges from 1 m (the frequency in this case is 300 MHz) to 1 mm (the frequency is 300 GHz).
Microwave radiation was widely used in the implementation of the method of non-contact heating of bodies and objects. In the scientific world, this discovery is intensively used in space exploration. Its familiar and best known use is in home microwave ovens. In heavy industry, it is used for heat treatment of metals.
Also today, microwave radiation has spread in radar. Antennas, receivers and transmitters are actually expensive objects, but they are successfully paid off due to the huge information capacity of microwave communication channels. The popularity of its use in everyday life and in production is explained by the fact that this type of radiation is all-pervasive, therefore, the object is heated from the inside.
The scale of electromagnetic frequencies, or rather, its beginning and end, represents two different forms of radiation:
- ionizing (the frequency of the wave is greater than the frequency of visible light);
- non-ionizing (radiation frequency is less than the frequency of visible light).
For humans, microwave radiation of non-ionized radiation is a danger that directly affects human biocurrents with a frequency of 1 to 35 Hz. As a rule, non-ionized microwave radiation provokes causeless fatigue, cardiac arrhythmias, nausea, a decrease in the general tone of the body and severe headache. Such symptoms should be a signal that a harmful source of radiation is near, which can cause significant harm to health. However, as soon as a person leaves the danger zone, the ailment ceases, and these unpleasant signs disappear on their own.
Stimulated radiation was discovered back in 1916 by the brilliant scientist A. Einstein. He described this phenomenon as the influence of an external electromagnetic field arising from the transition of an electron in an atom from an upper energy level to a lower one. The radiation that occurs in this case is called induced. It has another name - stimulated emission. Its peculiarity lies in the fact that the atom emits an electromagnetic wave - the polarization, frequency, phase, and also the propagation direction in it are the same as in the original wave.
Scientists used induced radiation as the basis for the operation of modern lasers, which, in turn, helped to create fundamentally new modern devices - for example, quantum hygrometers, brightness amplifiers, etc.
Thanks to the laser, new technical directions appeared - such as laser technology, holography, nonlinear and integrated optics, and laser chemistry. It is used in medicine for the most complicated operations on the eyes, in surgery. The monochromaticity and coherence of the laser make it indispensable in spectroscopy, isotope separation, angular velocity measurement systems and in light locating.
Microwave radiation is also radio emission, only it belongs to the infrared range, and it also has the highest frequency in the radio range. We encounter this radiation several times a day, using a microwave to heat food, and also talking on a cell phone. A very interesting and important application for him was found by astronomers. Microwave radiation is used to study the cosmic background or relic radiation of the Big Bang, which occurred billions of years ago. Astrophysicists study the inhomogeneities of the glow in some parts of the sky, which helps to find out how galaxies formed in the Universe.