Refractive Errors

About Refractive Errors:

Glasses (or spectacles) and contact lenses are two of the most common ways of correcting refractive errors. In eyes with normal vision, light focuses on the light-sensitive retina at the back of the eye. Once the retina senses light, it converts the light into the image that you see.

In refractive errors, the eyes are unable to focus light on the retina. This results in blurred vision. The solution is glasses or contact lenses. These bend the beam of light so it focuses properly on the retina. This should restore clear vision.

Normal vision: In normal vision, light rays from an object focus on the retina.

Refractive error: A refractive error is when the light rays focus either in front of or behind the retina. This causes blurred vision.

Types of Refractive Errors:

The four most common types are:

Short-Sight (Myopia)

Close objects look clear, but distant objects are blurry. This happens when light focuses in front of the retina because the cornea is too curved or the eye is too long.

Long-Sight (Hyperopia)

Distant objects look clear, while nearby objects look blurry. Sometimes, this can be hard to notice. In extreme cases, objects are blurry at any distance. Hyperopia is when light focuses behind the retina because the eye is too small.


With this disease, light focuses unevenly on the retina. This distorts the image and makes it blurry. It is due to changes in the curve of cornea.


Presbyopia is a natural part of ageing. Over time, the lens in your eye loses its ability to change shape. Light cannot focus as well as it did before, so nearby objects look blurry.

Risk Factors:

Near-sightedness, far-sightedness, and astigmatism can occur at any age. The risk of presbyopia increases with age. Adults older than 35 are most commonly affected.

Those with a family history of refractive errors are at a greater risk.


The most common sign is blurry vision. Other symptoms include:

  • Double vision
  • Difficulty reading
  • Seeing rings around bright lights
  • Squinting or squeezing your eyes to see better
  • Headaches
  • Eye strain

Treatment Options

The three main treatments are Spectacles, Contact lenses, and LASIK Surgery. In all cases, follow-up treatment may be necessary.

Key Points to Remember:

  • Regular eye check-up is a must! As you grow, your eyes grow too. Your lens strength may need to be updated.
  • If you or your child have a refractive error, all of your children should have an eye checkup
  • Whatever you choose – contact lenses or glasses – you MUST take care of them properly and wear them constantly, according to the doctor’s advice.
  • Vitamin A rich foods are good for eye health, but they are not a cure
  • Glasses will not make your eyes stronger or weaker. They will allow you to see better with your current eyesight.