What Happens During an Eye Test: Step by Step, How Long It Takes, and How to Prepare

You check in at reception, confirm your details, and complete a short questionnaire about your health, any medications, family eye history, and any visual symptoms. If you have a previous prescription, bring it along.

The optometrist asks about your vision since your last test, any problems (headaches, difficulty reading, dry eyes), your general health, and any medications. Be honest about symptoms, even minor ones.

The classic letter chart test. You read letters of decreasing size from a set distance (usually 6 metres, or reflected to simulate 6 metres in a smaller room). Tested with each eye separately and then both together. The result is expressed as a fraction such as 6/6 (normal) or 6/12 (reduced).

The optometrist places a series of trial lenses in front of your eyes (using a phoropter or trial frame) and asks 'which is clearer, one or two?' for each combination. This determines your exact prescription for glasses or contact lenses. There is no wrong answer. Just say which looks better.

Measures the pressure inside your eye. High pressure is a risk factor for glaucoma. Usually done with a puff of air (non-contact tonometry) or a small probe that briefly touches the eye (Goldmann tonometry). The puff of air is startling but completely painless.

A microscope with a bright, narrow beam of light examines the front structures of your eye: the cornea, iris, lens, and eyelids. You rest your chin on a support while the optometrist looks through the microscope. Checks for cataracts, corneal damage, and other conditions.

The optometrist shines a light into your eye (direct ophthalmoscopy) or uses the slit lamp with a special lens to see the retina, optic nerve, and blood vessels at the back of your eye. This can detect signs of diabetes, hypertension, macular degeneration, and retinal detachment.

You look straight ahead at a screen and press a button each time you see a small light flash at the edges of your vision. This maps your peripheral vision and is used to screen for glaucoma, strokes, and neurological conditions. Not always included in a routine test.

If you have chosen the enhanced test with OCT, the machine takes a 3D scan of your retina. You rest your chin on a support and look at a target. The scan takes about 30 seconds per eye. Non-invasive and painless.

The optometrist explains the results, whether you need glasses or a prescription change, any conditions found, and when to return. You receive a printed copy of your prescription. This is yours by right, even if you choose not to buy glasses there.