Since UV Index has been developed, more and more people pay attention to the risk of sunburn and the damage of UV radiation. UV rays have been classified into five categories and their respective risk levels are low, moderate, high, very high and extreme. Long time exposure to sunshine is closed associated with eye disasters, such as cataracts, macular degeneration, pingueculae and pterygia, phototkeratitis and so on. In addition, HEV (high-energy visible) radiation may cause low blood plasma levels of vitamin C and other antioxidants.

There are three types of UV rays, namely UVA, UVB and UVC, all of which are located just behind the violet portion of the visible spectrum. UVC rays are blocked by the earth’s atmosphere but UVB rays are quite dangerous. Spending much time outdoors, children with sensitive eyes need more UV protection from sunglasses.

Non-prescription sunglasses are popular because of their fashionable look and UV protective function. Though there are a lot of designer sunglasses without prescription and are purchased “over-the-counter” named “plano”, there are also sunglasses incorporated with regular eyeglass prescription.

Recently, performance-oriented sunglasses are popular among the professional and amateur athletes during outdoor activities such as mountain biking, snowboarding, and kayaking. Durability and specialty are the most important requirements of these sunglasses. Sunglass manufacturers provide new products constantly to meet the requirement such as best vision under extreme environments.

As the name indicates, sunglasses are usually used to protect you from sunlight. If your eyes are over-exposed to ultraviolet (UV) rays from the sun, you would have serious eye problems that may not become apparent until you are much older. Generally, the young are more susceptible to sun exposure than the old because they spend more time outdoors.

Recently, more and more designers pay their attention to sunglass business. Nearly every notable designer is on his/her way to sunglass market. Even some of high-end designers, such as Chanel, Dior, and Prada, are launching sunglass lines. Sunglasses and fashion are linked closely.

Besides eyeglasses for regular wear, there are still various types of specialty eyewear or “task-specific” eyeglasses. Since one pair of eyeglasses does not fit all sizes in most cases, those specialty eyeglasses such as computer glasses, driving eyeglasses and protective glasses are helpful in specific circumstances.