Choosing Eyeglass Lenses
Buying eyeglass lenses requires making decisions about the design of the lenses, the lens material, and any coatings you may want applied to the lens. A good place to start is an overview of eyeglass lens options.
Lens Designs
Lens design is a decision that's probably made for you. Most people get either single-vision lenses (to correct nearsightedness, for example) or bifocal lenses. Bifocals and other multifocals correct more than one vision problem, such as myopia and presbyopia (an age-related inability to focus on close work).
Many people who require bifocals or multifocals opt for progressive lenses. Progressives have a smooth progression of optical power, enabling you to see at intermediate distances as well as near and far. Another advantage is that they don't have bifocal lines, which can be unattractive and a tell-tale sign of age! Still others prefer reading glasses; the market has grown in leaps and bounds now that baby-boomers are wearing them and a wide variety of styles is available.
For those with double vision, a special prism in eyeglasses may be necessary. This lens enables light to be bent or reflected in certain ways and can also split white light into different wave lengths and colors, correcting the problem.
Lens Materials
Three factors will drive your decision on eyeglass lens materials: appearance, function and safety.
To look good, you'll want your lenses as thin as possible. An excellent choice is high-index lenses. People with strong prescriptions love them because not only do they get rid of the hated "Coke-bottle" appearance, but they're also lighter to wear. No more sore nose!
Tired of the hassle of switching between your eyeglasses and your sunglasses? Maybe you wrestle with sunglass clip-ons instead. You might want to look into photochromic lenses, which automatically darken when you step outside and return to normal when you go back indoors. If you think they don't work quickly enough, you'll be happily surprised to learn that today's photochromic lenses work more quickly than the ones from years back.
When safety is an issue, you must use polycarbonate: it is an extremely impact-resistant material, so it's ideal for sports and kids' eyeglasses. The American Academy of Ophthalmology has information about the best ways to prevent eye injuries [pdf / 447KB] during sports. You can also get information from Prevent Blindness America.
Lens Coatings
Lens coatings are useful for fashion and/or function. Anti-reflective coatings are both: they help you to see through the lenses better and keep glare from obscuring your beautiful eyes from others. Scratch-resistant coatings are particularly handy for plastic lenses: while plastic is nice and light, it's more scratch-prone than glass. UV coating protects your eyes from the sun's harmful rays, a possible risk factor for developing a cataract; you can get UV protection in both tinted and clear lenses. Fashionable mirror coatings come in many colors and prevent people from seeing your eyes.
Need More Info?
Your eye doctor or optician can provide further advice, or visit the Consumer Guide to Eyeglasses.