Do you get sun tan behind glass?

Answer 1

The previous answer by Erik is right, but it shoud be clarified.

All wavelengths of light have the ability to trigger the tanning process, but the higher energy wavelengths, (i.e. ultraviolet rather than infrared) cause this process to happen much, much faster.

Now, glass does filter out U.V. light, but sunglasses are rarely made out of glass lenses any longer for safety reasons. Most sunglasses now use polycarbonate or some other form of plastic. Unlike glass, these do not necessarily filter out U.V. as well as glass. So a pair of quality sunglasses will filter out most of the U.V. light, and you won't get a tan behind the glasses. A pair of cheap sunglasses, may filter almost none of the U.V. light, and you will get a tan.

So, if you get a tan behind your current sunglasses, toss them into the trash, because they are a real danger to your eyes, much worse than no sunglasses at all. Why? Because without any sunglasses, you are forced to squint and your pupils dialate and your eyes are largely protected from the high-energy U.V. light which has the ability to damage your cornea and retina.

But if you have on a pair of cheap sunglasses that block the visible light but little of the U.V. light, your eyes are open wide, your pupils dialated more, and much of that dangerous U.V. is spilling inside of your eye causing a lot of damage.

Answer 2

Suntan results from exposure to ultraviolet radiation gradually. Too much, and you just sunburn, the skin peels, you start all over again, and you significantly increase your risk of skin cancer.

Most glass absorbs UV, 2% to 99%, depending on the light wavelength and type of glass. So, glass will reduce tanning somewhat, but it depends a lot on the kind of glass.

The greenhouse effect does not result from glass converting UV to IR. Light is absorbed by the ground, and much of the energy is released as heat and IR, which do not penetrate the glass.

Answer 3

The ultraviolet light is what gives you a sun tan. When UV passes through glass, it loosed energy and converts to infra red. This is why greenhouses warm up with just sunlight.

This is why you wont get a sun tan.

Answer 4

I'm not a phsyicist, but you would recieve a greater tan behind glass, as the light is reflected through the lens and bounced off the fibres inside, intensifying the heat.

Answer 5

no u just get really hott

Answer 6

yup

Answer 7

Im sure you do.