UV rays are a form of electromagnetic radiation and exist on the electromagnetic spectrum with a wavelength slightly shorter than that of visible light.
This form of radiation got its name “Ultraviolet” because of the fact that UV rays have a wavelength just shorter than that of violet, the form of visible light with the shortest wavelength before being undetected by the human eye. Ultraviolet basically means “beyond violet.”
Ultraviolet rays are emitted by the sun and by manmade lamps known as UV lamps or lights.
UV light has a lot of uses in our modern society:
It can tan skin of course. 97-99% of UV rays emitted from the sun are blocked from our ozone layer. But those little rays that do make it through have quite an effect on life on Earth. That’s where we get all our Vitamin D. If any more of those rays got through we’d be fried all the time, and if any less got through we would be Vitamin D deficient. Crazy world!
Insects use UV light to navigate. That’s why they are attracted to those bug zappers people put out to get rid of pests.
Also, UV light in certain wavelengths, as used in a black light, has phosphorescent lighting properties. That’s why certain surfaces glow under blacklights, making them popular at parties!
We’ve developed certain dyes and markers that only show up under UV light, thus opening the door to all sorts of authentication and security applications. Remember that stamp you used to get on your hand at amusement parks? UV light again.
UV light with its phosphorescent lighting properties can detect many substances and particles that are harder to spot with the human eye, thus making UV lights extremely useful in certain laboratory conditions, not to mention crime investigations.
Our society uses UV light for many applications. Next time you are tanning, you can think about how fascinating UV light is!