The types of lens materials are glass, cr-39, polycarbonate plastic, and acrylic plastic. The highest quality of these materials, and the material suggested for persons concerned about vision quality is glass. Glass lenses are also the most scratch resistant, but they are prone to shattering when hit. The other three types of materials are all plastic and impact resistant. Acrylic plastic must be specifically treated in order for it to protect the wearer from UV rays.Lenses also vary in tint. A darker tint will absorb a significantly higher amount of light than a lighter tint. Different color tints also serve different purposes. An amber or orange tint will reduce blue light which is the chief component of glare. Therefore, these sunglasses are popular in sports that have a high amount of glare (boating, fishing, and skiing). Brown tints are good for driving, and Gray is good for golfing, running, or cycling. Different tints have different abilities to reduce glare. The best suggestion is to take the sunglasses use into consideration when choosing.Finally, sunglasses have a variety of coatings. UV protective coatings are a must for sunglasses. The sun's harmful UV rays can seriously damage eyes. Some sunglasses may have a dark tint, but do not have special coatings that protect against UV rays. Other coatings can help improve the scratch resistance on sunglasses. Additionally, Wholesale Inline Duct Fan Factory mirror or flash coated lenses, and anti-reflective coated lenses can greatly reduce the amount of light absorbed and reduce glare or "halo" effects. Once again, the coating choice should depend on the intended use of the sunglasses.Sunglasses are essential for people in a variety of situations. Casual sunglasses that are to be used when at the pool or beach do not have to be the most expensive sunglasses available. For most people, sturdy sunglasses that protect the eyes from UV rays and look good are more than enough. However, for anyone who is doing a sport that requires maximum visibility in sunny conditions, high-quality sunglasses are a must. Different lenses and frames can produce highly variant results. Anyone looking for sunglasses should understand in what context the sunglasses will be used, and then choose accordingly. An educated decision will usually result in one choosing sunglasses that he or she is very satisfied with.