The principle of choosing sunglasses

The concept of sun protection is becoming increasingly popular, but in Taiwan, many people still lack the concept of eye protection. In fact, the eyes are affected by long-term sun exposure abnormal may cause cataracts, corneal diseases such as. Therefore, under the sun in addition to rub suntan lotion, but also that there are pairs of sun-glasses to protect eyes. 
Polarized sunglasses lenses into the lens, color lens, color lens three types: 
(1) Polarized lenses special materials may be least squares from the land of the strong reflection of light, and the elimination of glare from horizontal polarization in order to protect the eyes, commonly used in the snow, mountain climbing, fishing, water sports activities. 
(2) coating color lenses is that the colored lenses or plating color, generally known as the sun glasses are mostly of this type. Such as that used for outdoor activities 
(3) refers to the lens color lens as light, strong or weak change the color depth of the lens itself. When the UV exposure to direct, so that produce color, ultraviolet one fail, they will automatically fade, very convenient. 
Sunglasses to choose the best color for the gray and green tea is the best color, the color will be the most abundant levels and the correct line features, such as the formula by adding anti-UV, but also enhanced filtering harmful solar rays. Followed by amber and blue, the rest of the color lenses are not suitable for outdoor activities, easily lead to eyestrain. 
The principle of choosing sunglasses: 
(1) through the lenses can still see their eyes indoor mirror, mirror lenses that not deep enough. 
(2) lenses must uniform, there is no designated stripes, spots, uneven surfaces, such as bubbles or vague phenomenon. To buy time, it can draw the glasses at about 30 cm in a vertical or flat line, moved up and down glasses, if the line is still straight as before, not as mobile and fixed glasses, then passes the. 
(3) will be the lens up and check the lens on the images shown are distorted or wavy, and if so, that it is a poor-quality lenses. 
(4) to check the frame and the surrounding parts is strong, the frame should be affixed to a comfortable working closely attached to the bridge of the nose and ears.