Different ways to classify sunglasses

Sunglasses are necessary during outdoor activities in a sunny day. Nowadays, sunglasses are provided by lots of manufacturers in numerous design styles, colors, materials and so forth. There are many other aspects to classify the wide variety of sunglasses on the market, such as frame type, lens type, coating, shade color and hinge etc.
Sunglass frames can be made of various materials, including metal, plastic, nylon, carbon and their potential combinations. In general, different brands have their own frame styles. For instance, Aviator sunglasses are a typical style that uses metal frames. Hydrophilic glasses can stick to the face even in the wettest conditions. Allowing full peripheral vision, wrap around sunglasses can completely block out sunlight.
The lenses of sunglasses also have different types. There are plastic lenses, glass lenses and polycarbonate lenses and so on. Lenses made of different materials suit different purposes. Being shatter resistant, plastic lenses are popularly used for sports. Another example is polarized lenses that are suitable for activities involving high glare such as fishing. One point is true that all types of sunglass lenses should have the ability to block out both UVA and UVB rays.
Sunglasses can also be classified according to different coatings applied on the lenses. Common coatings include blue-light filtering, flash coating, anti-reflective coating, mirror coating, silver and gold coating. Coatings can be applied to a lens in two ways. While regular gradient coating treats a lens from the top to the bottom, a double-gradient model only treats a lens at both ends. In order to know the specific function of each coating, it is necessary to read the claims provided by manufacturers.
Eyeglass lenses can be tinted with different colors, each of which plays its role in different ways. In general, amber-tinted lenses can reduce glare and brown lenses help wearers lessen eye strain. Yellow-tinted lenses are usually used for low-light conditions, while green lenses are generically suitable.
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