
Being a tax advisor is a hard job – Mr. Podlešák spends up to 14 hours at the computer dealing with hundreds of thousands of figures every day. So to relax he goes down to his
workshop in the basement…
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The term “infrared” comes from Latin where “infra” is a prefix meaning “below”.
Red colour has the longest wavelength within the spectral range of visible light. Infrared light has even slightly longer wavelengths. Used in this context, the term “longer” stands for lower frequency – hence the Latin “infra” for “below”.
Sir Frederick William Herschel, the amateur astronomer who discovered Uranus in 1781 also unveiled the existence of infrared radiation in sunlight at the outset of the 19th century. Herschel was familiar with Newton’s notion that light can be broken down into a number of chromatic parts by paging it through a glass prism. He assumed that the individual colours can contain various levels of heat and decided to conduct an experiment which was supposed to either prove or disprove his theory. Herschel let the light pass through a prism which divided it into the individual elements of the colour spectrum and then held a thermometer at the individual colours to measure they temperature. To do this he used three thermometers with blackened out bulbs. He inserted one of the bulbs into a selected stream of colour light while keeping the other two outside the colour spectrum.
When measuring the temperatures of violet, blue, green, yellow, orange and red colour he discovered that colours have a higher temperature than the control thermometers outside the spectrum. It also became clear that colours go up from violet to red part of the spectrum. Once Herschel understood the underlying system he chose to focus exclusively on red. This was the colour that showed the highest temperature and thus contained the most heat. What Herschel discovered at this point was, in fact, the invisible form of light beyond the visible spectrum, beyond red light. Later on his experiments led to the discovery of infrared light.
Infrared radiation is a frequency range on the electromagnetic spectrum and for us stays invisible. It is a form of radiating heat also called “infrared energy”. About 80% of sun rays fall into this spectral range as well as the waves of 2-13 micrometers in length such as those that are produced by PION.