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How Do Glasses Work?

About 75% of American adults wear eyeglasses or contact lenses to keep their surroundings in focus and allow them to read and use computers efficiently. Understanding how glasses work begins with the mechanics of the eye.

Everyone’s eyes are a little different. Not just in color, but the way they work and how well they see. When parts of the eye don’t function the way they should, people need glasses. Eyeglasses or contact lenses, also referred to as corrective lenses, help these people see clearly and enjoy the benefits of crisp and comfortable vision.

How The Eye Focuses Light

The eye has many parts that work together to produce clear vision. Parts of the eye include:

  • The pupil – allows light into the eye
  • The retina – the nerve layer at the back of the eye that the light focuses on
  • The cornea – the clear window at the front of the eye, which is the first and strongest focusing layer of the eye.
  • The lens – the second focusing system, which can adjust and fine tune the focusing light, depending on the distance of the object

When all of these parts of your eyes are correctly shaped and functioning properly, you don’t have vision problems and will have 20/20 eyesight. You are able to see clearly because like a camera, your eyes are capturing an accurate image and then sending that clear image to your brain, where it can be interpreted.

The function of your eyes is to bend rays of light so the image of whatever you are looking at is focused directly on your retina. The focusing of light directly on your retina allows it to record a sharp image that ensures your brain will interpret the image correctly and you will see the image clearly.

When the eye does not focus light directly onto the retina, this is known as a refractive error. Often, when a person has trouble with their vision it’s because of a refractive error causing the light to be focused either in front of (myopia/nearsightedness) or behind (hyperopia/farsightedness) the retina.

How Do Lenses Correct Vision Problems?

Optical lenses are manufactured in high-quality plastic or glass. Their function is to correct the refractive error by focusing light directly on the retina.

There are two main types of lenses:

  • Convex/Plus (+) lens – This lens corrects farsightedness, where the refractive error means light is focussed behind the retina. It bends the light, pushing the focal point of the light forward, to correctly focus on the retina.
  • Concave/Minus (-) lens – This lens corrects nearsightedness, where the refractive error means light is focussed in front of the retina. It moves the focal point of the light backwards, to correctly focus on the retina.

Wearing the correct power and type of lens compensates for your eye’s inability to project light directly on your retina.

If you are interested to learn more about how glasses work, or think you may need glasses contact Optix Family Eyecare in Plainview to schedule an appointment.

At Optix Family Eyecare, we put your family’s needs first. Talk to us about how we can help you maintain healthy vision. Call us today: 516-252-0725 or book an appointment online to see one of our Plainview eye doctors.

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