Corrective Lenses for Refractive Error

Eyeglasses improve vision by correcting the way light is refracted onto the retina as it passes through the eyeglass lens and into your eye. After your eye doctor determines the type of lenses you need based on the results of an eye exam, you can purchase frames and lenses wherever they are sold. 

People with significant refractive error previously required thick lenses. Today, however, manufacturers can make thinner lenses for almost any prescription. Some newer lenses can also correct more than one type of refractive error within the same lens—for example, bifocal, trifocal, and progressive lenses, or multifocal lenses, are useful for people with both myopia and presbyopia. 

In addition, many newer lenses no longer have a horizontal line in between the different lens types and can be customized to your needs. For example, some “transition” lenses become tinted sunglasses in bright light. Some new lenses are also scratch-resistant, glare-resistant, and hard to break. These advances are especially helpful for children who wear glasses.

Occasionally, our eye doctors recommend eyeglasses customized to your occupation to correct your vision under a set of specific circumstances. For example, if you have trouble focusing on objects up close and you spend many hours a day looking at a computer screen or using small tools—for instance, to create or repair crafts or electronics—your doctor may provide you with a pair of eyeglasses created specifically to help you accomplish these tasks without straining your eyes.

Reading Glasses

People who develop presbyopia as they age have trouble seeing close-up objects, which makes reading especially difficult. Your eye doctor determines the correct strength of reading glasses for you during an eye exam.

Even though reading glasses are available without a prescription, doctors recommend using a prescription to ensure your glasses are customized to your vision. In addition, some people require a different strength lens for each eye, so you may be able to read better with a prescription pair of reading glasses. Glasses customized by a doctor may fit better and be more comfortable, too.

Contact lenses are small, bowl-shaped pieces of hard or soft plastic that are placed directly on the eyeball to correct refractive error. If you decide on contacts, your ophthalmologist or optometrist can perform a contact lens fitting as part of an eye exam. 

During the fitting, your eye doctor works to determine the appropriate curve, thickness, and diameter of the lens to perfectly fit your eye. The optometrist or ophthalmologist gives you a test pair of contacts to try on in the doctor’s office to ensure they feel comfortable before you purchase them.

Contact lenses come in hard and soft varieties. Soft contacts are generally more comfortable, and most people who are nearsighted, farsighted, or have regular astigmatism prefer soft contacts. Some soft contacts can be thrown away every day; others are worn for as long as one year, with daily cleanings, before being replaced.

Hard contact lenses—which have the same bowl shape as soft contacts but are rigid—are prescribed for people who have irregular astigmatism. The hard contact lenses maintain their shape instead of conforming to the natural shape of the eyeball, so they correct the shape of the eyeball as well as the refraction of light that passes through the contact lens and eye. 

Because contact lenses are worn on the eye, you need to clean and inspect them daily to prevent dirt or other foreign objects from causing an infection or scratching your cornea. Your eye doctor shows you how to wear, inspect, and clean your contact lenses.