Infrared rays are often used to detect people or animals in the dark.
Infrared rays are a type of electromagnetic radiation with a wavelength that is longer than the wavelength of light that can be seen (therefore, it has a lower frequency ), but shorter than the wavelength of microwaves ( the frequency of infrared rays is higher).
Before moving forward with the definition, it is necessary to analyze the etymological origin of the two words that give shape to the concept:
- Ray derives from the Latin radius , which can be translated as "rod" .
- Infrared comes from the English language. In this sense, it must be said that it was the American physicist Samuel Pierpont Langley who proceeded to coin the term and he did so using two Latin components: the prefix infra- , which is synonymous with "below" , and the word russus , which means "red" .
In short, the line originating in the place where a certain type of energy is generated, which propagates in a certain direction, is called a ray . Infrared , for its part, is an adjective that refers to radiation whose wavelength is longer than red.
Infrared ray emission
A body that is at a temperature higher than -273.15º Celsius (equivalent to 0 Kelvin ) can emit infrared rays with wavelengths between 0.7 and 1,000 micrometers . According to the wavelength, we can distinguish between near infrared rays , mid-infrared rays and far infrared rays .
It is important to keep in mind that all bodies emit energetic radiation, which is linked to temperature . In the case of living beings, most of the radiation is infrared.
When we talk about thermal sensation , we are referring to what a person feels beyond the temperature of the environment. This is mainly due to the radiation that reaches us from the sun's rays: if we receive more energy than we emit in the form of infrared rays, we will feel hot, even when the ambient temperature and body temperature remain constant.
The remote control or remote control usually uses infrared rays.
Its use
As explained, infrared rays can be used in special devices to see bodies in the dark , recording the radiation they emit. The greater the amount of infrared rays emitted, the greater luminosity can be captured.
Currently, infrared rays are used very frequently, in various areas and with a wide set of purposes and functions, among which we could highlight the following:
- As an outdoor heating element, especially in places with terraces, shop windows...
- To detect water leaks much more quickly and without having to break any installation.
- The military also makes use of infrared rays through certain systems to detect a target even in conditions of little or no visibility.
- To develop the drying of paints within the field of industry.
- In gastronomy, to roast certain dishes more quickly and achieving a homogeneous result.