The color of the lens, usually has nothing to do with the lens material, is the lens material does not determine the color of the lens.
Life bespectacled person's innumerable, everybody saw the lens color is various, and the more common lens color is yellow, blue, purple, grey, brown, dark brown, green, etc. , different color lenses with a fight ultraviolet, absorb radiation effect is also different.
Glasses with color and there is no direct relationship between the lens material, people in order to better protect the eyes, add a layer of coating layer on the lens.
A lot of color coating layer, on the surface of the lens, is better to make the lens light transmittance, and uv protection, glare, radiation effect is better, so all sorts of color in the different lenses.
The so-called blue glasses, it is added blue film in the surface of the lens, so the appearance of color in the sun, the blue light.
Blue glasses compared with yellow lenses, dark brown lens, its protection against ultraviolet ray, filter out glare, reduce the effect of radiation is not very good.
That is to say, the lens surface after dealing with the blue film, although it improves the ability of resist ultraviolet ray, glare, but the percentage of the overall against less, than the yellow lenses and lens resistant effect is good. It's light brown.
So, wear the blue glass lens, the visual will be slightly a little dark, don't suggest to wear daily life.
That is why we usually common is dark brown and grey sunglasses.
Whether it is a kind of color glasses, have the effect of good for the eyes.
Although uv protection, for example, blue lens, such as glare, radiation effect is poorer, but the blue lenses can fight eyestrain, namely can effectively alleviate visual fatigue.
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