Loading the content... Loading depends on your connection speed!

Eye Test Guide

The following guide provides a brief overview of what is involved in each of the different tests your Optometrist may carry out:

Non-Contact Tonometer:

The tonometer measures the pressure inside your eyes, known as intraocular pressure. A puff of air is directed onto the eye. The air bounces back at the instrument, giving a measurement of the pressure inside each eye. It only takes a couple of seconds to perform and is an important test, as high pressure can indicate the early stages of glaucoma, a sight-threatening condition. Caught early, these can easily be corrected and treated.


By observing how the eye processes a beam of light, your Optometrist can determine if you suffer from myopia (nearsightedness), hypermetropia (farsightedness) or if you have astigmatism. The test only takes a few seconds and is extremely accurate.

The Test Chart:

The test chart is probably the most familiar piece of equipment. The most common chart is the Snellen chart, which is a series of letters of differing sizes – ranging from the largest at the top to the smallest at the bottom. The results for one eye often vary from the other, so each eye will be tested individually before both eyes are finally tested together. The Optometrist flips different lenses in front of your eyes that change how clearly you can see. Depending on your answers, they change the lenses until you have the clearest, most comfortable vision possible.

The Opthalmoscope:

This is used to examine the retina at the back of the eye, including the blood vessels and the front of the optic nerve. It can also detect any changes in the health of this area that may indicate underlying diseases such as diabetes, high blood pressure or macular degeneration. The optician darkens the room and shines a bright light into each eye in turn using the ophthalmoscope.

Fixation Disparity Test:

This determines if your eyes are working well together and how much correction may be needed to balance your eyesight. You will be asked to look at a panel and say whether the bars appear to be in line both horizontally and vertically.

The Slit Lamp:

The slit lamp is a powerful, illuminated microscope that is used to examine the outer surface of your eyes – the cornea, the iris and the lens – to check for abnormalities or scratches. The slit lamp examination is particularly important for contact lens wearers.

Visual Field Screener:

This is used to determine your field of vision and to locate any ‘blind spots’ within that field. A visual field screener randomly flashes dots of light on a black background. If you fail to see any of the dots, this can be an indication of a blind spot.

Testing your Focus:

Most people who have trouble focusing on either near or distant objects can have their eyesight easily corrected by prescription lenses. To find out if you need corrective lenses, your Optometrist will test your ability to focus on both close-up and distant objects.

Digital Retinal Screening:

We aim to provide you with the highest standard of eye care so with the latest technology we can take photographs of the back of your eye (the retina).

The digital retinal camera helps us to detect eye conditions such as Glaucoma, Age related Macular Degeneration and Diabetic Eye Disease. We can monitor conditions by taking and storing photographs on successive visits.

It only takes seconds to take a photograph and it can be carried out during your routine eye examination or at a separate visit.

Mobile version: Enabled