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There are many types of lenses on the market today. Which one should choose is becoming a big problem. Maybe you still have no ideal of eyeglasses before entering a spectacle stores. Here we provide some information for you, and you would find the best lenses for your eyeglasses.
Modern eyeglass lenses
Modern eyeglass lenses are lighter, thinner, and more scratch-resistant than glass lenses or the older, common plastic lenses, as technology advances.
Single vision lenses provide visual correction for a single focus only —either near- or farsightedness, but not both. The single vision lens is prescribed if you need correction for one field of vision, either for distance or items up close.
Hi-index lenses are made of a special plastic material that refracts light in a different way than regular plastic lenses. With hi-index lenses, vision can be corrected with less material, making the lens much thinner. The higher the number, the thinner the lens. Because they are thinner, hi-index lenses are also lighter, making them more comfortable to wear.
Polycarbonate lenses are thinner and lighter than traditional plastic eyeglass lenses. They also offer 100 percent ultraviolet (UV) protection and are up to 10 times more impact-resistant than regular plastic lenses. Since then, polycarbonate lenses have become the standard for safety glasses, sports goggles and children’s eyewear.
Aspheric lenses are ideal for strong prescriptions, because they are flatter and thinner. They are any lenses whose surface angles and profiles are neither part of a sphere nor part of a cylinder. Conventional or non-aspheric lenses have the same curve across their entire surface, like a ping-pong ball.
Photochromic lenses are lenses that change their colour according to light conditions. When exposed to sunlight they darken quickly to eliminate glare and to protect the eyes against UV. These lenses are generally nearly clear when it is dark. They block 100% of UV rays to protect your eyes from UVA and UVB radiation which could damage your eyes.
Polarized sunglasses reduce glare and are useful for sports and driving.Light reflected from water or a flat surface can cause unwanted glare. These lenses may cause the liquid crystal displays on the dashboard of cars to appear invisible.
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