Astigmatism

 

If your eye is shaped more like a rugby ball than a football, light rays are focused on more than one place in the eye, so you don’t have one clear image. This may make it hard to tell ‘N’ from ‘H’, for instance.

Glasses which correct this may feel strange at first, although vision with the glasses will be clear. Often astigmatism occurs together with either long- or short-sightedness and glasses are used to make the focus clear.

 

  • In a normal eye, light entering the eye is focussed by the cornea and the lens

  • …to form a sharp image at the back of the eye on the retina.

  • Astigmatism occurs when the cornea is slightly “rugby ball shaped”.

  • The effect of this is that light rays

  • …come to a focus at different points in the eye.

  • This results in blurred vision when looking in the distance and reading.

  • The degree and angle of astigmatism can vary from eye to eye.

  • If you have astigmatism you may notice that objects of certain orientations look clearer.