A Quick Peek at Eyeglass Lenses
Vision Basics: Refractive Errors
In a healthy eye, the cornea is a clear dome-shaped window that allows light rays to pass through and focus on the retina behind it. Distortions in the cornea can cause light rays to bend (or refract) at odd angles and fail to achieve sharp focus; this is called refractive error. Eyeglass lenses correct the error by adjusting the angles at which light enters the eye, so the images we see will be clear and sharp.
Which Camp Are You In?
There are several conditions caused by refractive errors in our eyes. About half of all people have nearsightedness (myopia) which means you see clearly close up but not at a distance. Conversely, if you’re farsighted (hyperopia), you can see clearly over a distance but not close up.
Other causes of refractive error include cataracts, when the naturally clear lens is cloudy or isn’t as flexible as it should be, and astigmatism, a distortion of the eye’s curvature. Both of these conditions can cause blurry vision.
To the Rescue: Types of Corrective Lenses
Single-vision glasses have single-purpose lenses. They are designed to help you see clearly either close up or far away.
Multifocal glasses do two or more jobs in the same lens. With bifocal lenses, one part is focused on distance vision, while the other is used for near-vision activities such as reading. Trifocals have three different corrections – for distance, intermediate, and near vision – all in one pair of glasses.
Progressive lenses provide a smooth transition from distance to near within the lens, without a visible dividing line.
More Lens Options
Materials: Once there was only glass, but now most lenses are plastic. Plastic lenses are lighter, more flexible, and less likely to shatter. For sports activities, your doctor may recommend polycarbonate or the new Trivex lenses for even greater impact resistance.
Protective Coatings: Anti-reflective coatings reduce glare. Ultraviolet (UV) coating helps to protect your eyes from the sun’s harmful radiation.
Prescription sunglasses: These lenses have your corrective prescription plus protection against bright sunlight and glare.
Photochromatic lenses automatically adjust based on light exposure.
Since change is inevitable in our eyes as well as in life, it’s important to have your eyeglass prescription and general eye health checked regularly by an Atlantic Eye physician. Schedule an appointment by calling our main office number, 732-222-7373, or go to www.atlanticeye.com.