Which Lenses Are Right for Your Glasses?
Selecting the lenses that best fit your needs can be just as important as the style and fit of the frames. Different types of lenses each have their pros and cons, and at Nationwide Vision, we can help determine what’s right for you.
Types of Lenses
Glass lenses function well, but tend to be heavy and can break easily, potentially resulting in serious injury to the eye. Glass lenses are no longer widely used for eyeglasses.
These lenses are made of a plastic polymer called CR-39. They are low cost and provide excellent optical quality. CR-39 plastic is a popular material for eyeglass lenses.
These lenses are made from a newer plastic with similar characteristics to polycarbonate lenses. They are also lightweight, thin, and impact-resistant, but may result in better vision correction than polycarbonate lenses.
High-index plastic lenses:
These lenses are thinner and lighter than CR-39 plastic lenses because they have a higher index of refraction and may also have a lower specific gravity.
Aspheric lenses are made up of differing degrees of curvature over its surface, making the lens thinner and flatter than other lenses. These lenses provide a much larger usable portion than other lenses.
These lenses are made from glass or plastic and become tinted when exposed to sunlight, eliminating the need for prescription sunglasses. A car windshield could block the UV rays from the sun preventing the glasses from darkening.
Treatments for Eyeglass Lenses
For the most comfortable, durable and best-looking glasses, these lens treatments are a necessity:
Anti-scratch coating - All non-glass lightweight lens materials have surfaces that are softer and prone to scratches. Plastic lenses require a factory-applied anti-scratch coating for adequate lens durability. Most of today's modern anti-scratch coatings can give your lenses scratch-resistance almost as high as glass.
Anti-reflective coating - Anti-reflective coatings eliminate reflections in lenses that reduce contrast and clarity, especially at night. They also greatly reduce the visibility inside the frames, so you aren't distracted by reflections in your lenses.
UV-blocking treatment - People should protect their eyes from UV exposure starting in early childhood due to the negative effects of cumulative UV exposure. Polycarbonate and most high-index plastic lenses provide total UV protection built-in, due to absorptive characteristics of the material. For plastic lenses, be aware that an added coating is needed to provide equal protection afforded by other lens materials.
Photochromic treatment -This treatment enables eyeglass lenses to tint automatically in response to the sun's UV and high-energy visible light rays, and then quickly return to clear when indoors. Photochromic coatings are available for nearly every lens material.
To find eyeglasses that are right for you, call us at (877) 222-4281 or visit us at any of our Nationwide Vision locations.