Buy sunglasses: What are the cheap models worth?
A pair of sunglasses should protect against too bright a light. But not only from the visible light that dazzles us, but also from the invisible, the ultraviolet light (UV). Because too much light overtaxes the eye. The pupil protects the eye by reducing its size and reducing the amount of light that enters. If that is not enough, sunglasses will help. Particularly important is the sunglasses on the sea and in the snow, where the sun is reflected, as well as in the mountains, where the radiation is stronger.
When we wear sunglasses, our pupils dilate and we can see better. The problem with this: If the sunglasses are bad and does not filter out the radiation, even more harmful UV light gets through the enlarged pupils with sunglasses in the eye than without. The result can be painful inflammation of the cornea or even permanent damage to the retina.
Do cheap eyewear provide adequate UV protection?
Unfortunately, this can not be seen from the outside. If you want to be sure with your sunglasses, you can have the optician's UV protection checked with a measuring device. However, tests have shown that even glasses for under ten euros, which were sold in Germany, have the necessary UV protection. Only with some cheap imitations from Asia the UV protection was not enough. Pay attention to the CE mark on the inside of the bracket. This mark guarantees that the safety requirements of the EU are met - including UV protection.
You should keep this in mind when buying sunglasses
The best UV protection is of no use if the sunglasses are too small: Then the radiation hits the eye from above or from the side. The glasses should enclose the entire eye socket.
Beware of distorting lenses: they strain your eyes and cause headaches. Hold the glasses with outstretched arms and look through the glasses at a straight line (for example, an edge). Only buy the glasses if the glass does not bend or bend the line.
Take a close look at the glass. It should not have any irregularities like streaks or inclusions.
Test the hinge between bracket and socket. It has to work properly. Also take a look at the processing of the frame and spectacle lens.
Sunglasses have a different degree of darkening (anti-glare category). However, this glare protection has nothing to do with UV protection. The glare protection ranges from low (category 0) to very high (category 4). For everyday life in Germany usually ranges from 65 percent to 75 percent (Category 2). On the water and in the mountains, a tint of 85 percent (Category 3) is the better choice. For high quality sunglasses, the glare protection category is on the inside of the bar.
For driving, sunglasses should have a maximum of Category 3 glare protection. For eyeglass lenses, brown, gray or green are the ideal tinting colors as they are least likely to distort traffic lights or hazard warning lights. Glasses that darken themselves are unsuitable for driving. The reason: the car windows filter out the UV rays already for the most part. The lenses do not darken in the car.
