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Optical radiation

The term "optical radiation" comprises the infrared radiation (IR), the light visible for man (VIS) and the ultraviolet radiation (UV). Optical radiation is part of the electromagnetic spectrum with a wavelength range from 100 nm to 1 mm.

The sun is the natural source of optical radiation. In addition optical radiation can be produced artificially (as e.g., in lasers, lamps, radiant heaters, sunbeds, electric arcs).

What is optical radiation?

Optical radiation comprises the regions of ultraviolet radiation (UV), visible light (VIS) and infrared radiation (IR). The natural source of optical radiation is the sun. Optical radiation can also be generated artificially.

What does visible light mean?

Light or "visible light" refers to the visible region of the electromagnetic spectrum – that is, the range of wavelengths that trigger brightness and colour perception in humans. It lies between UV and infrared radiation. Most people can perceive wavelengths of between about 400 nanometres (nm) and 780 nm visually.

Wavelength of UV rays

What is UV radiation?

Ultraviolet (UV) radiation covers the wavelength range of 100 nanometres (nm) to 400 nm. It is the most powerful type of optical radiation. UV radiation is not visible to the human eye and cannot be perceived by the other senses either. UV radiation causes acute and long-term effects on the human skin and eyes and is an important environmental parameter. The intensity of UV radiation is subject to continuous worldwide monitoring. The measuring results are published as UV Index.

What is infrared radiation?

Infrared radiation (IR radiation) - also referred to as thermal radiation - is part of the electromagnetic spectrum. It follows the visible radiation in the direction of longer wavelengths ranging from 780 nanometres to 1 millimetre.

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