How Contact Lenses Work

Contact lenses can help you see the world in a completely different way. Even if you wear eyeglasses, contacts can be more comfortable, less disruptive, and virtually unnoticeable.

In the US, over 30 million adults wear contacts. According to the Vision Council of America, about 156 million more wear eyeglasses either constantly or for reading

The first contact lenses

While modern contacts are a recent invention, they’ve been in the works for over 500 years. Leonardo Da Vinci drew sketches of how eyesight could be corrected with a glass lens full of water.

Later in 1887, artificial eye maker F. A. Muller was the first to design and wear glass on the eyeball to correct vision. However, these first contacts covered the entire eye and cut off oxygen to the cornea, making them very uncomfortable.

In 1948 optical technician Kevin Tuohy created the first all-plastic lens, similar to today’s lenses. This design also covered only the cornea, making it less annoying.

What contact lenses do

If an object is blurry when viewed too close or too far away, light is entering the eyeball at the incorrect angle. Contacts (as well as eyeglasses, magnifying glasses, and binoculars) refocus the light to correctly reach the back of the eyeball.

If a far-away object is blurry in your vision, you have myopia (or nearsightedness) meaning light doesn’t correctly reach the back of your eye. This requires a contact lens that is curved inward to move the light.

Farsighted people (with hyperopia) have light intake that reaches too far back into the eyeball. Contacts to correct this are curved outward.

Why contacts over glasses

Contacts are designed and worn to make day-to-day life easier for nearsighted or farsighted people. Contacts are favored because they:

• Are small and portable
• Don’t obstruct vision like eyeglass rims may
• Aren’t easily removed like eyeglasses
• Weigh virtually nothing