The article reveals the concept of “spectrum”: what is it, what are the types, where it is used. The ranges of electromagnetic waves visible and inaccessible to the human eye are described . Areas of life that are developing thanks to the science of spectra — spectroscopy — are shown.
World visible to man
The human eye is a miracle of nature, the pinnacle of evolution. All kinds of living things perceive the world in their own way. We got the role of the audience. Psychologists say that up to ninety percent of information our brain perceives through colors and shades. Since vision is so important, it is worth answering the question: "Spectrum - what is it and what role does it play in human life?" Surely even the smallest readers have heard a simple count about the rainbow: "Every hunter wants to know where the pheasant sits." The first letters of this simple expression suggest the order of color names. Thus, most people have colors from red to purple. Everything that the human eye perceives is a combination and illumination of these shades. However, we do not see all parts of the spectrum. Only the visible range is available to us. It is so called precisely because the eyes of our species, homo sapiens, perceive it. It is noteworthy that some people see a little more - for example, in the near infrared or ultraviolet region. It is said that the former is more commonly available to women, and the latter to men.
Spectrum concept
So, the distribution of the value of a certain quantity is the spectrum. What is this concept, now we will understand. Let's say a person brings a lot of products from a store. The lightest of them is a chicken egg, the heaviest is a chicken carcass. The mass spectrum of the purchases brought lies between these two limits. And if we weigh each product individually and compile a table, how much and what mass is in the bag, we will get a full range of masses.
Electromagnetic spectrum
But most often this refers to another aspect of the concept of “spectrum”. What is meant by this, we will disclose below. Electromagnetic waves rule our world . You can talk about their nature for hours, but let's not get distracted. Recall only that they are generated by moving charged particles. The scale of electromagnetic waves includes much more than the spectrum of colors that our eyes are able to see. Radio waves, infrared radiation, ultraviolet radiation, x-rays and even more so gamma radiation - all this is inaccessible to our direct perception. Imagine if a person were able to fix, “see”, for example, Wi-Fi, or a radio signal in a car, or body temperature. It seems unbelievable that this is possible. The world would be completely different if people had this. However, there are creatures on our planet that perceive the surrounding space in this way, for example snakes or cockroaches.
Spectrum Types
Surely many, after reading the previous paragraph, will ask themselves: "Spectrum - what is it? Are it really only electromagnetic waves?" The answer is simple: no. What will be discussed below has some relation to statistics, but let the reader not be scared, because nothing complicated is supposed. So, if there is any quantity that can take some discrete values in the lower and upper limits, then a spectrum is possible for it. What this value may turn out to be is completely irrelevant. It does not even have to be a countable type of size or volume. It may seem unbelievable, but in everyday life, this occurs at every turn. Mom cooks well forty-three dishes - this is her culinary range. A child reads from two to ten books a month - this is the spectrum of the number of books read. But all the printed publications read determine the spectrum of human knowledge. Dad only drinks cherry and watermelon juices, and this is his range of drinks. As you can see, the concept is used very widely. Even if a person is standing in front of an ice cream counter, this is the spectrum of his choice. Not to mention the daily options for action, due to personal experience and morality.
Types of optical spectrum
Speaking of electromagnetic waves, we touched on such a thing as the spectrum of colors. However, everything is far from simple. The usual color of an object determines what wavelength a photon is reflected from its surface. But any solid body has, in addition to external faces, also an internal structure, which is hidden in its volume. It is spectra that help determine it. But in this case, it is not the photons that vibrate, but the particles of the substance itself. And these vibrations, or rather their spectrum, reports everything about the connections within the structure. It is impossible to see or somehow fix such information without special devices.
The use of optical spectra
However, the scope of these spectra is truly unlimited. There is a separate branch of physical knowledge dedicated to their study and application. Biology, crystallography, nuclear energy, space exploration and exploration could not have reached the modern level if humanity had not had a wonderful way to explore the world - spectroscopy. Even medicine knows examples of using a tool like spectrum. Determining the chemical composition of blood and plasma will tell you exactly what elements are missing in the body. Many diseases can be detected in the early stages. This is especially important for cancer and multiple sclerosis.