Infrared — “Under The Rainbow”
As every rainbow demonstrates, the optical spectrum (the portion of the electromagnetic spectrum that is visible to the human eye) includes the seven colors red, orange, yellow, green, cyan, blue, and violet. By definition, red is the color with the longest wavelengths of visible light, and violet is the color with the shortest wavelengths of visible light. Outside of the optical spectrum are different types of invisible light or electromagnetic radiation. Among these types are infrared radiation (IR) and ultraviolet (UV) radiation. “Infra” and “ultra” are Latin words meaning “below" and “beyond,” respectively, so infrared radiation, or infrared light, is literally “below red,” while ultraviolet light is “beyond violet.”
In 1800, German astronomer William Herschel discovered infrared light. Researching the heat effects of the colors of the optical spectrum, he found that the temperature in the colors increased as he went from violet to red. Herschel also discovered that the temperature continued to increase beyond the color red, into a region of invisible light that he named “infrared.”
Infrared light is divided into three distinct segments with specific ranges of wavelength measured by microns. One micron is equivalent to 1/1,000,000 of a meter. These segments include near infrared, middle infrared, and far infrared. Far infrared light is often referred to as thermal radiation or thermal light, and its wavelengths measure between 5.6 and 1,000 microns. The light or energy from fire and sunlight that we perceive as heat is actually far infrared.
The far infrared radiation (FIR) emitted by the sun should not be confused with its harmful ultraviolet radiation. Far infrared light provides the healthy benefits of natural sunlight without any of the dangerous side effects of exposure to ultraviolet radiation.
Infrared Is A Part Of Our Daily Lives...
Far infrared rays are a fundamental, indispensable part of life on Earth. All creatures in our environment — people, animals, plants — receive and radiate them. And now, with far infrared saunas becoming increasingly common, we humans are wisely taking steps to benefit from those rays and improve the quality of our own lives.
A key characteristic of far infrared light is its ability to heat an object directly without raising the temperature of the air surrounding the object. In technical terms, this is called direct light conversion. It’s perhaps best demonstrated when you’re outdoors on a summer day and a large cloud moves in front of the sun. In the shade, you do not feel as warm as did when you were basking in the direct path of the sun’s energy. The air temperature, though, is no cooler than it was before the cloud obscured the sun. Yet, by moving between you and the sun, the cloud has blocked the sun’s far infrared rays from reaching you. That’s why you feel cooler even though the temperature of the air surrounding you did not change.
This technology has been captured for its great health benefits, and is used in our Infrared Sauna and Infrared Message Bed.