There are a lot of decisions to be made once your eye doctor gives you your eye glasses prescription. After picking out your new frame, you’ll need to consider what materials your prescription lens will be made from. Historically, eyeglasses were made of just that, glass. This provided a high quality image but had drawbacks. Glass was a heavier material and there was concern of it shattering in a pair of spectacles. It is now rarely used, but can still be found in high quality camera lenses and telescopes. These days most spectacle lenses are made of modern plastics. Here are the most common ones here and their benefits and differences.
CR-39 Plastic: This is one of the most common materials used today to make eyeglasses. It is half the weight of glass making comfortable to wear. It provides excellent optics for a clear image.
Polycarbonate: This material is great for people participating in sports, work in a dangerous environment, and for children. Polycarbonate lenses are more than 10 times more impact resistant than conventional plastic lenses. In fact the material was first developed to be used as the eye shield for astronaut helmets. Polycarbonate lenses are also a required for drill mount frames to keep the lens from shattering.
High Index: If your eye glass prescription is larger than average a high index lens is a great choice. High prescriptions require more light bending correction. This requires a lens to be thick and can make them unattractive. This material has a higher index of refraction allowing for large prescriptions lenses to be made thinner.
There is a lot more than just a frame to consider when making your eyeglass purchase, and the information can at times be overwhelming. Our opticians both in Belle Meade and Hendersonville can help you narrow down your options, and choose the lenses that will give you optimal visual acuity.
