Everyone knows that the sun sends out light one is uv, often by ultraviolet irradiation is harm to human body, common is the skin become poor black, of course also be damage to the eyes.
This time we will need a pair of uv protection glasses, that what is uv protection glasses?
Ray-ban sunglasses RB3449 men silver / 004/55 uv lens dazzle colour blue glasses is in fact a kind of sunglasses, but it has the function of uv protection.
So how do you know whether the sun glasses have this feature?
There are two small method.
Look at the label sunglasses uv sunglasses tags or lenses to see such as 'ultraviolet prevention', 'UV400' obvious signs.
'UV index', that is, filter out the effect of ultraviolet light, this is buying a standard sunglasses is very important.
In the 286 - nm wavelength -
400 nm UV light is called, is generally 100% of the UV index is impossible, the vast majority of sunglasses UV index at 96% -
Sunglasses ultraviolet prevention function, the express way generally have the following: a)
Labeled 'UV400' : this means that the lens of uv cutoff wavelength of 400 nm, namely the wavelength (
Under 400 nm spectral transmittance of big value tau Max (
No more than 2%;
Labeled 'UV', 'anti ultraviolet' : this says the lens of UV cutoff wavelength of 380 nm, namely the wavelength (
Under 380 nm spectral transmittance of big value tau Max (
No more than 2%;
Labeled '100% UV absorption' : this means that the function of the lens is 100% for UV absorption, namely in the UV range of average transmission ratio is not greater than zero.
To achieve the above requirements of sunglasses, is in the true sense of uv protection function of sunglasses.
The use of money and yanchao pen to verify in the absence of the instrument, ordinary people also can detect whether the sunglasses have uv protection function.
Take a piece of money, put the lenses on the anti-counterfeiting watermark, illuminates with yanchao pen or counterfeit detector in the lens, if you still can see the watermark is this pair of sunglasses is not uv protection, if not see, is this pair of sunglasses for uv protection.
Ray-ban sunglasses RB4225 men 646/55 transparent many friends will want to, really works on uv protection sunglasses?
The answer is yes.
Although uv helps the body to absorb calcium, but too much ultraviolet light is easy to cause the skin coarse serious will cause skin cancer, and eyes is a very vulnerable place, more vulnerable, uv protection glasses can be as a shield to protect his eyes from ultraviolet rays.
The above information compiled by glasses sunglasses factory network, see the related articles for more knowledge of fashion sunglasses!
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