How do i know if sunglasses really have UV protection?

Question

I had some cheap sunglesses but i thought they were ok since it said "100% UV protection" on them. But i doubt it since everytime I wore them outdoors i got horrible headaches and my eyes would look sunburned.

So how can i know if it's true?

Answer 1

I think your eyes looking sunburned is a different issue than them getting sunburned that may have nothing to do with your sunglasses. Talk to an optometrist about your eyes. As for the sunglasses, the 100%UV protection has become very common, so unless you get them from a stall in the middle of the street for $2 you shouldn't have a problem.

Typically, most sunwear lenses will be UV absorptive to some degree. If lenses are marked CR-39R plastic, about 88% of UV light is absorbed. If sunglasses are polycarbonate, UV absorption will be 100%.

All better quality polarized non-prescription sunglasses sold through optical stores are 100% UV absorbing. For the very inexpensive polarized sunglass — thin, bent sheet polarized types provide UV absorption. Lenses that are polycarbonate are usually UV absorptive. However, many cheap sunglasses use a material called triacetate. This material absorbs only about 40% of the UV rays. Lenses may also be made of other acrylic materials, which will vary from partially to fully absorbent.

To know that your lenses are 100% UV absorbing, purchase them from reputable companies, specialty sunglass stores or from an optical professional. They are aslo the ones that will have the photometer to tell you if the lenses are good or not.

Answer 2

What do you mean...your eyes would look sunburned ??

The vast majority of even the cheapest sunglasses give the full UV filtering .

What gives headaches usually is that the lenses on the cheapies are full of distortion.

If you want good protection...spend about 100.00 on a real pair, with optical quality lenses.

You will never want to go back to the cheapies after having a good pair from an optical store.