How do glasses work

If you have nearsightedness or farsightedness, it means your eyes have difficulty focusing light on the spot of your retina that produces the clearest image. Glasses correct vision by allowing your eyes to focus light on the correct spot of your retina.

The curved frames bend light, and with the right prescription, these frames manipulate the light to reach the correct spot on your retina. The result is a clear, crisp image. With nearsightedness, the image focuses in the front of the retina, and with farsightedness, the image focuses behind the retina. Individuals with astigmatism have an irregularly shaped cornea, which means it bends light in different directions.

Your optometrist will give you a series of tests to determine what degree of nearsightedness and farsightedness you have. Next, he or she will write a specific prescription for glasses that will bend light to focus on the correct spot on your retina.

Shop All Contacts. Shop All Sale. How Do Glasses Work? When you look at a beautiful naturescape, for example, this happens: These three mechanisms fine tune the light as it scatters and merges to land on the retina The image shrinks and curves to match the natural shape of the retina Reaction to light is relayed from the retina to the brain and is translated into an image If we can say anything about the human eye, it is beautifully complex!

How do I know if I need glasses? How long will it take to adjust to new glasses? Sign Up. Sign in or Create Account for Exclusive Savings! Sign In Create Account. Albert, Dufferin County and many other cities across Canada! Our Flagship Store. Products search. How Glasses Work. The numerical prescription in diopters is always marked with a minus - symbol. These lenses are used to correct nearsightedness myopia.

Convex lenses. These lenses are thickest in the center, like a magnifying glass. They are used to correct farsightedness hyperopia. Cylindrical lenses. These curve more in one direction than in the other. They are used to correct astigmatism. If your child is old enough, let them play an active role in choosing their own glasses. Think about the features below when buying eyeglasses for children:. Ear pieces that wrap around the ear cable temples are advised for children under 4 years.

Straps may also be advised to hold the glasses in place. About 45 million Americans wear contact lenses. About 9 out of 10 people who wear contact lenses use soft lenses. In general, there are 2 types of contact lenses:. A contact lens prescription includes more information than an eyeglass prescription.

Special measurements are taken of the curvature of the eye. In addition, your child's healthcare provider will determine if their eyes are too dry for contact lenses.