Uncovering the Eye Test: What Is It and How Does It Work?

by | Jun 28, 2022 | News

A standard eye test can be highly useful in checking the quality of eyesight, and detecting any underlying health conditions or issues that may be present. It usually involves a general check-up with a conversation about your current vision, followed by a number of tests with a professional optician. But what specifically happens during the eye test and what tools are used to measure the eyesight of an individual? Read on to find out!

What happens?

The first stage will typically involve a pre-test, which can be carried out by either an optical assistant or optician. They will usually begin by asking a series of questions to find out more about your lifestyle and optical history. Some of the questions that might be asked are:

  • Do you currently take any medication at all?
  • Do you have a prescription for anything currently? If so, do you also already wear glasses?
  • Do you have any eye problems or genetic health history that might be useful for us to know, for example glaucoma?
  • Do you have any concerns or issues with your current vision as it is?

Reading from an eye chart with numerous letters on it is then common. This may be a projected or classic version. The optometrist will typically cover an eye at a time in order to get rid of any discrepancies between the right and left eye.

Once this assessment has been carried out, there are several tests that the optician can use with the following tools:


The tonometer is a non-contact instrument used to evaluate the pressure inside the eye. The tool will send several small puffs of air against each of your eyes, which will slightly flatten the cornea (front part of the eye). The length of time that it takes to flatten your cornea is converted into a specific measurement of the pressure within the eye. High pressure inside the eye can be an indicator of the earliest stages of glaucoma.


This is used to find out how well your eyes are able to focus and can be especially useful in determining an estimate of your prescriptions. You will typically be asked to focus on a specific point of light or image. A quick measurement will be taken once your eyes are in full view of the machine.


This is a handheld tool that the optometrist will use to clearly view the inside of your eye. A light will be shone on your eye, allowing the optometrist to see into the pupil right back to the back of the eye at an area known as the fundus.

Slit lamp

This tool is especially important for people who wear contact lenses. A powerfully illuminated microscope is utilised to examine the outer surface of the eyes, and this allows the optometrist to check how well your personal contact lenses are fitting.

Why book an eye test?

No matter how healthy or old you feel, it’s incredibly important to receive consistent eye examinations from a qualified professional. A sight test is a great way to see if your vision has deteriorated, and will also check for any eye conditions that could be potentially harmful in the future.

To book an appointment with Vision Care, click here or give us a call on 01452 410 494 –we’d be happy to hear from you!

 The Eye Site is a collective of reliable and trusted expert Independent Opticians, and we are here to help give you the very best advice, care, and solutions for all of your eye care needs.

 We believe that you and your family deserve to receive the very best care. Our brilliant branches are run by our friendly teams, all of whom will go above and beyond to make sure that your time spent with us is both productive and a pleasant experience.

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