You could be fined £1000 and given three penalty points on your licence if you are found to be driving without meeting specific eyesight standards according to the DVLA.
At the start of a practical driving test, participants are asked to correctly read a number plate on a parked vehicle.
If you cannot, it will result in an automatic fail without even stepping foot inside the car and your licence will be revoked.
However, if your eyesight deteriorates after you've passed your test, you could be driving illegally and can be prosecuted.
Driving eyesight standards that if not met could land you a £1000 fine
According to the DVLA: "You must be able to read (with glasses or contact lenses, if necessary) a car number plate made after 1 September 2001 from 20 metres.
"You must also meet the minimum eyesight standard for driving by having a visual acuity of at least decimal 0.5 (6/12) measured on the Snellen scale (with glasses or contact lenses, if necessary) using both eyes together or, if you have sight in one eye only, in that eye."
The DVLA website adds that drivers must have an "adequate field of vision" which can be tested at an optician.
If your eyesight has changed, or you had a medical condition, and the DVLA aren't told you can be fined up to £1000 or issued points on your licence.
The Gov.uk website says you must tell the DVLA if you:
Have a certain type of eye condition that affects both eyes (or one eye when you only have vision in one eye)
Have been told you may not meet the visual standards for driving by a GP, optician or eye specialist
There are also certain eye conditions you must tell DVLA about:
Diabetic retinopathy (with laser treatment)
Diplopia (double vision)
Nyctalopia (night blindness)
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Tips to protect your eyesight when driving
Car leasing company Hippo Leasing spoke to an optometrist and clinical advisor from the Association of Optometrists to produce some tips to help protect your eyesight when driving.
Wear prescription glasses and sunglasses when driving
Many short-sighted people will need to wear glasses when driving to have a clear view of the road.
According to the DVLA, “You must wear glasses or contact lenses every time you drive if you need them to meet the 'standards of vision for driving'”.
Hippo Leasing said to keep a pair of prescription glasses in your car so you don't forget them, and "opt for no-glare polarised sunglasses that are ideal for driving as they’ll prevent glare from objects or the road".
Reduce the risk of dry eyes when concentrating on the road by using eyedrops
Roshni Kanabar, an Optometrist at the Association of Optometrists (AOP), said: “We generally tend to blink a lot less whilst concentrating which can lead to the natural coating of the tears over your eyes, to start to evaporate, making them dry and uncomfortable.
"Drivers must consider what makes them most comfortable, especially when driving long distances. For example, try and remember to blink, and it’s important to take regular breaks on your journey.”
If you get dry eyes when driving, Hippo Leasing said to be sure to use moisturising eye drops to keep your eyes feeling comfortable.
Use the in-built car visor to block out harmful UV rays
If sunglasses aren’t doing the trick with blocking out the sun, then pull down the in-built car visor to further protect your eyes from the bright light - just be sure it does not interfere with your view of the road.
Keep the windscreen wash topped up to clear any obstructions to vision
The windscreen of a vehicle can easily become dirty due to the build-up of debris from wet roads, insects, and rain - and without screenwash able to wipe this debris away, your vision of the road can be impacted.
Mr Kanabar added: “Glare and dazzle are often a common reason for reduced visibility – a dirty windscreen can affect this so cleaning your car windows inside and out can make a huge difference.”
Failure to drive with a clear windscreen can land motorists with a £1,000 fine as under Regulation 30 of The Road Vehicles (Construction and Use) Regulations 1986 - drivers are told they must keep all glass clear of obstruction.
Install a £5 tinted strip on the windshield for extra protection against UV rays
Another way to protect your eyes from the sun is to install a tinted strip on the top of the windshield.
You can buy a self-clinging sun strip to add to your vehicle for under £5, says Hippo Leasing.
Take a break when travelling long distances to avoid eyestrain
According to Rule 91 of the Highway Code, a break of at least 15 minutes should be taken every two hours on a long-distance journey.
Driving continuously for longer than two hours can cause eye strain, which can lead to headaches, eye discomfort, and dangerous fatigue.
Tom Preston, Founder of Hippo Leasing, says: “Our eyesight is precious and we should all be taking the steps necessary to to protect it at all costs.
“It is dangerous to drive with impaired vision and you could be putting yourself and other people’s lives at risk when you can’t view the road clearly, read road signs properly, or see potential hazards.”
Mr Kanabar added: “Aside from being able to see a good level of detail, which is important for things like reading road signs, it means you can also spot objects moving in your peripheral vision, such as cyclists coming out of side roads, and to be able to detect objects which don’t stand out clearly from the background – enabling you to anticipate what’s about to happen and adapt your driving to the situation.
"Whether you wear glasses or not - regular sight tests are vital for drivers. This is because your optometrist will test your vision as well as examine the health of your eyes.
"You should have a sight test every two years, or more often if your optometrist recommends it.”