Sunglasses, also known as sun mirror for the purposes of shade. In the sun usually rely on to adjust the size of the pupil to adjust the flux when the light intensity more than the human eye to adjust, it will cause harm to the human eye. Outdoor activities, especially in the summer, many people are using sun mirror to block the sun in order to reduce eye adjustment caused by fatigue or light to stimulate the damage.
The sunglasses are a prevent sunlight strongly stimulate caused by the human eye injuries, eye care supplies, with the improvement of people's material and cultural level, the sunglasses can be as beauty or special jewelry to reflect the personal style.
The sun's rays reach the earth's surface contains UV, the cornea and lens of the human eye is most vulnerable to UV damage eye tissues, "cataract" is closely related eye diseases. Due to environmental damage to the ozone layer, as well as people's summer outdoor activities increase UV damage to the human eye can not be ignored. Wearing sunglasses is to protect the eye from UV damage better way, but pay special attention to the choice of sunglasses.
In accordance with the provisions of the international standards, the sunglasses are classified as areas of personal eye protection supplies, sunglasses wear in the summer, the main function is to block the sun glare. However, international standards again sunglasses subdivided into "fashion mirror" and "general use with a mirror. Standard quality requirements of the fashion mirror is relatively low. "Fashion Mirror" is the style, the wearer focus on the decorative rather than protective function. The standard of "general purpose mirror" quality requirements are more strict, which include requirements for UV protection, as well as refraction and prism of the indicators.
