What Is Astigmatism

What Is Astigmatism?

There’s no stigma about having astigmatism. In fact, one study found 63% of subjects have astigmatism. So, what is this curiously named eye condition? Although it sounds serious, rest easy, it’s just a part of your prescription.

Let’s consider your prescription as describing the power of your eye. Astigmatism means that your power is not the same for the whole eye. In fact, what it means is that if the eye has a certain power in one direction, then the perpendicular direction has a different power. To understand more about eye power and prescriptions, let’s visualize it.

Normal Eye vs Astigmatism


To have the same power for the whole eye, it’s likely close to perfectly round. That is, the eye is shaped like a soccer ball. If we have astigmatism, the eye is shaped more like the side of an AFL football. In one direction the eye is flatter. Much like the example, the direction 90 degrees to it is more curved.

Eye Ball Curves Sphere vs Astigmatism

In a glasses prescription with astigmatism, your optometrist specifies:

  • the power in the flatter direction
  • the difference between the flat and steep powers
  • the angle of the flat direction

As mentioned, most eyes are not perfectly round. Hence astigmatism is a very common eye condition. So don’t let the word scare you. It is quite common after all.


What Happens In Astigmatism?

Without correction, astigmatism results in blurry vision. Specifically, it blurs in a way that smears objects. Alternatively, it may make objects seem indistinct. So, without glasses or contact lenses, the eyes will squint or strain to try and make things clear. This can lead to headaches or eye pain over time.

So why does all this happen?

What Does The Blur In Astigmatism Look Like
What Does The Blur Look Like?

Because the eye power differs in different directions, images blur in different directions. It is this uneven blurring that causes smearing. With uneven blurring and smearing, a dot could look like a line from far away. Just imagine how things would look for your child at school with an undetected vision problem!


How To Correct Astigmatism?

Fortunately, most cases are easy to correct for. Most likely a pair of glasses or contact lenses will solve your problem. For higher levels of astigmatism, we can custom design contact lenses and have a specialty pair made up. In fact, even in soft disposable contact lenses we can reach up to -6.00 in power! So, if you’ve previously been told your prescription is too high for contact lenses, we are happy to take a look.


Want To Know More?

Our optometrists at InFocus Optical are more than happy to help you see well. All our standard eye tests check for astigmatism among other things. For complex cases we have specialty equipment to map your eye in 3D. Often this is to design a specialty contact lens mould.

Book your next eye test at InFocus Optical  for a complete vision and health check today.