How Do Contacts and Glasses Work?
Submitted by Karen Saland on Sun 02/24/2019 - 01:27
If you’re having trouble reading or seeing the blackboard, it’s possible that you need glasses or contacts. Contact lenses and glasses are designed to correct refractive errors by helping your eyes focus light properly onto your retina.
You may have a refractive error if:
- Your vision is blurry or hazy
- You have headaches
- Your eyes hurt
- You see a glare around bright lights
- You have to squint to see well
- You see double
- You have trouble driving at night
To understand how corrective lenses work; let’s first review how your eyes see. Your eyes have lenses that focus light on the retina, or back of the eye. The retina changes the light into electrical signals that are sent to the brain. The brain uses these signals to create an image of what you see.
The cornea and lens bend the incoming light so that the image is focused on the retina, which is located at the back of the eye.
Many people’s eyes are abnormally shaped. This means that the lens can’t focus light on the retina. Depending on the type of vision problem you have, the light can fall in front of or behind the retina. This creates a blurry image.
Glasses and contacts change the direction of light so that it hits the retina and creates a clear picture.
Eyeglasses consist of a frame with glass or plastic lenses that sits on the bridge of the nose and is supported by two legs, called temples, that rest on the ears. Glasses lenses come in different prescriptions depending on what type of vision problem you have. Lenses correct your vision by refocusing light onto the retina (back of the eye).
Contact lenses are small, round lenses that are placed directly on the eye’s surface and work in much the same way as glasses. They correct your vision by focusing light on the back of the eye. The difference is that contacts sit on your eyeball instead of in front of your eyes.
Glasses and contact lenses can be prescribed through a comprehensive vision exam with Dr. Saland in Dallas. To learn more or to schedule an exam, contact Saland Vision at 214-691-8000 or salandvision.com.