The Lowdown on Lenses

When it’s time for your next pair of eyeglasses, you may initially feel bewildered by the array of available lens choices. What type, material, and lens coatings do you need? Let’s demystify some current lens technology to help prepare for your next visit to the Atlantic Eye Optical Department.

I. Types of Lenses

Single-vision lenses solve several types of focusing problems:

Myopia or nearsightedness, when you have trouble seeing far-away objects.
Hyperopia or farsightedness, when you have trouble seeing up close.
Presbyopia is blurry near vision that usually happens with age. Reading glasses have single-vision lenses that help you read up close.

Multifocal lenses correct distance vision along with presbyopia.

Bifocal lenses correct for reading on the bottom and for distance on the top. Specialized “double-D” bifocals also have segments at the top for glancing up at objects in the intermediate or near range.
Trifocal glasses have lenses with three different lens corrections for distance, intermediate and near vision.
Progressive lenses have a smooth transition instead of visible dividing lines between zones. They can cause more distortion than other types of lenses, which makes these types of glasses difficult to wear for about 10% of people. (For more on progressives, see ).
Computer glasses have multifocal lenses designed to help prevent eye strain. They also help office workers to easily switch focus between different distances. Our April blog talks more about this,

II. Lens Materials

Plastic lenses are lighter and more flexible than glass. They are also safer because the lenses are less likely to shatter. These lenses have inherent UV light-blocking ability.
Polycarbonate lenses are impact-resistant, so often recommended for sports and other activities to help prevent eye injuries.
Trivex is a newer plastic material thats meets the same safety standards as polycarbonate but is less distorting.
High index lenses are thin, lightweight plastic for people who need high visual correction. They reduce the “coke bottle” look that comes with thick-lens glasses.

III. Protective Coatings

Anti-reflective coatings reduce glare and also allow more light to pass through. This improves your ability to see small patterns and letters. These coatings are especially helpful for people bothered by the glare of headlights and other lights while driving at night.
Ultraviolet (UV) coatings help protect your eyes from the sun’s harmful radiation.
Polychromatic coatings allow you to wear one set of prescription glasses for both inside and outdoors. These lenses adjust to have a darker tint in sunlight and a lighter tint indoors. In some environments, it may take several minutes for the lens tint to change from dark to light.
Scratch-resistant. Most lenses today have this built in.
Mirror coatings are purely for looks, or to hide your eyes from view.

IV. The most important takeaway?
Don’t leave your choice of eyeglass lenses to an online marketplace. Your Atlantic Eye optician is highly qualified to help you make the best decision for your individual needs and lifestyle. And when it’s time to pick out those fab frames, we’ve got some tips at