How the Eye works

When you look at something, light passes through the front of your eye, and is focused by the lens onto your retina.


The retina is a delicate tissue that is sensitive to light. It converts the light into electrical signals that travel along the optic nerve to your brain. The brain then interprets these signals to "see" the world around you.

Your retina has two main layers, a thin one called the pigment epithelium and a thicker one, called the neural retina.

The neural retina contains many millions of cells called photoreceptors and these cells convert light into electrical signals that travel to your brain.

Light is focused onto a tiny area of the central retina called the macula. This specialised area of your retina is about the size of a pinhead.

The macula contains a few million specialised photoreceptors called cone cells. These cone cells work best in bright light levels and allow you to see fine detail for activities such as reading and writing and to recognise colours.

The rest of your retina, called the peripheral retina, is mostly made up of the other type of photoreceptors called rod cells. Rod cells enable you to see when light is dim and provide your peripheral vision.

Peripheral vision is what you can see to the sides and above and below when you are looking at something straight ahead.

diagram of eye

Eye ALERT !!!

We recommend that you contact an optometrist or ophthalmologist immediately if you experience an unexpected change in vision, or odd visual effects like:

  • a line you know to be straight looking wavy, or
  • a shadow obscuring part of your vision, or
  • bright flashes of light and/or new and persistent dark blobs (floaters).

Flashes and floaters are harmless in themselves, but they may be a sign of a retinal problem. And because some sight-threatening conditions are symptomless in their early stages we also encourage everybody to have regular eye examinations. If you would like to receive our quarterly newsletter regularly, join us by contacting or download our membership form >>