Purchasing the right sunglassesWritten by Timothy Gorman
Sunglasses come in many different styles shapes, colors and even Designer Brands. They can be purchased for as low as $5.00 and go as high as upper hundreds. But it is not all about personal preference and making a fashion statement. The true function of sunglasses is protection from Ultra Violet Rays.
There are different lenses to choose from when out on hunt for sunglasses. * Blue blockers are usually found in amber colors. They are popular with skiers, boaters and especially pilots due to fact that they block out that blinding blue light. * Photo chromic lenses are lenses that adjust levels of darkness according to level of Ultra Violet Rays that are being exposed. * There are also Mirror coated Lenses; they are best for limiting amount of light in. * Gradient Lenses are another type of lens that you find on sunglasses. They are darkest on top and gradually get lighter as tint reaches bottom of lens. They are extremely helpful to people who drive for a living. The other Gradient lens is called double gradient. These lenses are darkest on top and bottom with lighter tint in center of lens. They are also not recommended for driving.
Prescription eyeglass specialty lensesWritten by Timothy Gorman
There are many different lenses that have been specially created for certain purposes and needs.
An aspheric lens is one of lightest weights of all lenses. They are available in bifocal or single vision prescription eyeglasses. The Allyl Resin plastic lens is also very light in weight. They do not offer protection from ultra violet rays that other lenses offer. The best lens on market is High index plastic lens. It offers highest level of ultra violet ray protection. It is light in weight and thin. It is also most expensive lens to purchase, but by far it is highest quality lens, as well.
There are also many different coatings that can be applied to your prescription eyeglasses. It can be done by lens manufacture or at most Optometrist offices'. Photo chromic coating adjusts to intensity of light that it is exposed to. The come in brown or gray tint, and are available in glass or plastic.