Contact Lenses

By: Maihan waizi

What are contact lenses and what are they used for?

Contact lenses; a thin plastic lens placed directly on the surface of the eye to correct visual defects often used other than wearing glasses. In 1508, famous Leonardo da Vinci suggested his sketches and thoughts and had said "the optics of the human eye could be altered by placing the cornea directly in contact with water( Heiting,2014).Mainly contact lenses are used for eye vision as an alternative for eye glasses but is also used for a change in eye color.

How do contact lenses work?

Contact lenses work the same way as eyeglasses do: they alter the direction of light rays to focus light properly onto the retina. Depending on your eye weakness contact lenses work differently. For instance if you are nearsighted , light rays focus too early within your eye, they form a focus point in front of the retina instead of directly on it. Although if your farsighted your eye does not have enough focusing power which means the light rays fail to form a focus point by the time they reach the retina.

Advantages and disadvantages of contact lenses?

Advantages of contact lenses:

  • Contact lenses provide predictable vision correction.
  • They eliminate the need to wear eyeglasses all the time.
  • Contacts provide better side vision than eyeglasses.
  • A wide range of lens types is available to meet individual needs.
  • Can change eye color
  • Some people prefer the way they look when wearing contacts rather than eyeglasses.


Disadvantages of contact lenses:

  • Cleaning and disinfecting your lenses can be complicated and inconvenient. You need good hand-eye coordination to clean, insert, and remove the lenses.
  • There is an increased risk of corneal infections, scratches, and scrapes.
  • Lenses can be easily damaged or lost.
  • Some people can't wear contact lenses comfortably. After going through the initial discomfort and expense of contact lenses, some people continue to find them uncomfortable.
  • Can cause dry eyes
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APA reference

A Consumer Guide to Contact Lenses. (n.d.). Retrieved from http://www.allaboutvision.com/contacts/


Pros and Cons of Contact Lenses-Topic Overview. (n.d.). Retrieved from http://www.webmd.com/eye-health/tc/pros-and-cons-of-contact-lenses-topic-overview


Heiting, G. (n.d.). When Were Contact Lenses Invented? Retrieved from http://www.allaboutvision.com/contacts/faq/when-invented.htm