1. The most important thing serve your glasses to protect your eyes from ultraviolet radiation. So always buy quality sunglasses with UV-filters that block 99-100% of UVA and UVB radiation. The label on the glasses must be marked UV 400 or 100% UV protection.
2. As high mountain eyes are exposed to very strong sunlight impact, UV-filter should be stronger. The glasses, which have poor UV-protection, can cause great harm vision – wearing their pupil does not shrink and it violates even minimum protection of the eye to light.
3. Color of sun your glasses is not irrelevant – it helps the absorption of light as it passes through the glass. Each color has certain qualities:
• Gray reduces the brightness of the light without affecting the perception of the surrounding colors;
• Brown reduces unwanted by flashes, including those of the blue spectrum of sunlight, which can cause blurring, but changing perception surrounding colors;
• Yellow lenses are suitable for driving in fog because they reduce blur of blue light so that the image really is cleared, but they change more surrounding colors;
• The green reduces unwanted glare and filter portions of blue light as It gives a very good contrast of the image;
4. polarization glasses is their third defense after UV-filter and color – the glass is in the form of vertical polarization grating thus take away the horizontal reflections from water, snow and other smooth and reflective surfaces. Glasses with vertical polarization are very suitable for skiing, fishing and sea.
5. wont young children should wear sunglasses, even if you do not like to wear them – so caring for the health of their eyes.