Visual impairment is when a person has sight loss that cannot be fully corrected using glasses or contact lenses.
It's estimated that as many as two million people in the UK may be living with this sort of sight problem. Of these, around 365,000 are registered as blind or partially sighted.
It's important to visit an optometrist (optician) for an eye test at least every two years so they can check for signs of vision loss.
If you already have visual impairment, it is still important to have a regular eye test, as your optometrist can monitor for further changes in the eyes and advise on making best use of your vision.
Find an optician near you.
How vision is tested and measured
There are two main areas that are assessed when your vision is tested:
visual acuity – central vision used to look at objects in detail, such as reading a book or watching television
visual field – ability to see around the edge of your vision while looking straight ahead
The main tests used to assess your visual acuity and field are described below.
Visual acuity testing
A test called the Snellen test is often used to measure your visual acuity. It involves reading letters off a chart on which the letters become progressively smaller. This chart is used during a routine eye test.
After the test you are given a score for your visual acuity. A Snellen score consists of two numbers. The first number represents how far away from the chart you were able to successfully read the letters on the chart. The second number represents how far away a person with healthy vision should be able to read the chart.
So if you were given a visual acuity score of 6/60, it means you can only read at 6 metres away what a person with healthy eyesight can read at 60 metres away.
Visual field testing
There are a number of different tests that can be used to assess your visual field.
One test involves looking straight ahead at a device while lights are flashed on and off at the edges of your vision. You will be asked to press a button every time you see a light. This shows any gaps in your field of vision.
Alternatively, you may be asked to follow an object (or the tester's hand) with your eyes as it is moved across your field of vision. You will be asked to say when you first see the object and when you can no longer see it.
Types of visual impairment
Visual impairment is usually classified as either ’sight impaired’ or ‘severely sight impaired’. These classifications are based on the results of the tests described above.
Sight impairment, previously called ‘partial sight’, is usually defined as:
having poor visual acuity (3/60 to 6/60) but having a full field of vision, or
having a combination of slightly reduced visual acuity (up to 6/24) and a reduced field of vision or having blurriness or cloudiness in your central vision, or
having relatively good visual acuity (up to 6/18) but a significantly reduced field of vision
Severely sight impaired
The legal definition of severe sight impairment (which was previously called ‘blindness’) is when ‘a person is so blind that they cannot do any work for which eyesight is essential’.
This usually falls into one of three categories:
having very poor visual acuity (less than 3/60), but having a full field of vision
having poor visual acuity (between 3/60 and 6/60) and a severe reduction in your field of vision
having slightly reduced visual acuity (6/60 or better) and a significantly reduced field of vision
Causes of visual impairment
Most causes of visual impairment in the UK are conditions that develop as you get older. About 8 in every 10 people with visual impairment are over 65.
However, losing your vision is not an inevitable part of ageing. It is often the result of a condition that can either be treated or sometimes even prevented. This is why it's so important to have regular check-ups with your optometrist.
Some of the most common causes of visual impairment include:
age-related macular degeneration (AMD) – where the central part of the back of the eye (the macula, which plays an important role in central vision) stops working properly
cataracts – where cloudy patches can form within the lenses of the eyes
glaucoma – where fluid builds up inside the eye, damaging the optic nerve (which relays information from the eye to the brain)
diabetic retinopathy – where blood vessels that supply the eye become damaged from a build-up of glucose
In some of these cases, such as cataracts, treatment can at least partially restore your vision.
Vision loss caused by AMD, glaucoma and diabetic retinopathy cannot usually be reversed. However, there are several treatments that can prevent further damage to vision, or at least slow down the progression of these conditions.
Getting help and support
There are support services, charities and devices that can all help make life easier if your vision is impaired.
Just because you have low vision, it does not mean you are no longer able to work or live independently.
With the help of assistive technology, training and support, many people who are either partially sighted or blind can continue to live full lives and work in demanding roles.
Registering as visually impaired
If you are visually impaired, it is important to register this with your local authority. This is not compulsory, but it can entitle you to a range of benefits, such as:
Disability Living Allowance (DLA) or Personal Independence Payment (PIP) – a tax-free benefit to help with any costs a person has relating to their disability or illness
a reduction in the TV licence fee
a tax allowance
reduced fees on public transport
To register, your visual acuity and visual field will have to be tested by an ophthalmologist (a doctor who specialises in diagnosing and treating eye conditions).
If the results show you are sight impaired or severely sight impaired, you will be issued with what is known as a Certificate of Visual Impairment (CVI) and a copy will also be sent to your local social services who can offer practical support.
Help and support if you have a visual impairment
Being told you have a visual impairment that cannot be treated can be difficult to come to terms with.
Some people go through a process much like bereavement, where they experience a range of emotions - including shock, anger and denial - before eventually coming to accept their condition.
If you are diagnosed with visual impairment, you may be referred to a specialist low-vision clinic. Health professionals working at these clinics can help you understand your condition and cope with your diagnosis. They can also advise on practical things, such as vision aids and lighting, and let you know about further sources of help and support.
Probably the most useful thing you can do after being diagnosed with visual impairment is to contact a support group for people with sight loss.
Royal National Institute of Blind People
The UK’s leading charity for people with visual impairment is the Royal National Institute of Blind People (RNIB).
The RNIB operates a helpline for people affected by visual impairment. The helpline is open from Monday to Friday from 8.45am to 5.30pm on 0303 123 9999. You can also email helpline staff at firstname.lastname@example.org.
The RNIB's website is specially designed for people with a visual impairment and provides a wide range of useful information and resources, and an online community.
The site also has an online shop that sells different products specially designed for people with a visual impairment.
Action for Blind People
Another useful organisation is Action for Blind People, a national charity that provides practical help and support for visually impaired people.
It’s particularly useful for advising on day-to-day practicalities of living with a visual impairment, such as adjusting your home to make it easier to get around and offers advice and courses on independent living, finances and employment.
It also has an online community where people can share experiences with others facing sight loss.
There are many local voluntary organisations around the country that provide support for people with visual impairment.
The website for their umbrella organisation, Visionary, includes a postcode search feature to help find organisations near to you.
It is recommended you contact your local social services department to inform them you have been diagnosed as having a visual impairment.
You may be entitled to a range of benefits as well as practical support, such as help with housework and cooking meals.
Changes to your home
Most people with a visual impairment can continue to live at home. However, you will probably need to make some changes to your home, especially if you live by yourself.
There are several important pieces of equipment you may find useful:
Big-button telephone – both landline and mobile models are available from the RNIB online shop.
Computer – the internet can provide a real sense of connection to friends and family as well as other people with a visual impairment. It is also a practical way of finding out information and obtaining goods and services. Big-button keyboards, screen display software and text readers are available from the RNIB.
Community alarm – this small wearable device has an alarm button. If pressed it sends an alarm signal to a response centre, which will alert a nominated friend or carer. Your local authority should be able to provide you with more information.
Bright lighting – bright light bulbs and adjustable lights are essential for your home, especially in the kitchen and the stairs (areas where you are most likely to have an accident). Fluorescent bulbs are recommended, as these produce the most light and tend to be cheaper in the long term than conventional bulbs.
The way your house is painted can also make it easier to find your way around. Using a two-tone contrast approach, such as black and white, can make it easier to tell the difference between nearby objects, such as a door and its handle or the stairs and its handrail.
Reading and writing
If you are having problems reading standard texts in books, newspapers and magazines, there are several options available.
One of the simplest options is to use one of a number of types of handheld magnifying device that you can hold over the page to help you read. These can obtained from a number of sources including hospital low visions services, optometrists, local voluntary organisations and the RNIB.
The RNIB also has a collection of large print publications you can borrow, as do most libraries.
Some people choose to use an e-reader to help them read. E-readers are handheld devices that allow you to download books and subscribe to newspapers and magazines on the internet. You can then set the device to display text at a larger size.
If you are unable to read at all, you could:
sign up to the National Talking Newspapers and Magazines scheme, which can provide audio versions of more than 230 titles by email or on CD
sign up to the RNIB Talking Books Service, which can send you audio books to listen to on your computer or on a device known as a DAISY player
You can also install screen-reading software on your computer that will read out emails, documents and text on the internet.
A charity called Communication for Blind and Disabled People has released a free screen reader for the PC called Thunder. Similar software is available for Apple devices, although you may have to pay a small fee.
There are also voice recognition programmes where you speak into a microphone and the software translates what you say into writing. These programmes can also be used to issue commands, such as closing down the internet and moving from one website to another.
Some people who are severely sight impaired, particularly if they have had the problem from a young age, choose to learn Braille. Braille is a writing system where raised dots are used as a substitute for written letters.
As well as Braille versions of books and magazines, you can buy Braille display units, which can be attached to computers that allow you to read the text displayed on a computer screen.
Computer keyboards in Braille dots are also available.
There are several different methods you can use to get around independently if you have a visual impairment.
Many people who are visually impaired find it useful to use a long cane when travelling.
This is a long, usually foldable, cane that can help you get around by detecting objects in your path. It also lets drivers and other pedestrians know you have a visual impairment.
To get the most from a cane, you will need to attend a training course in how to use it. The RNIB helpline can provide more details on training.
The charity Guide Dogs has been providing guide dogs for people with visual impairment for many years.
Guide dogs can help people with a visual impairment get around, providing both a sense of independence and companionship.
If you apply for a guide dog, Guide Dogs provide all the essential equipment free of charge and can offer financial assistance if needed for things like food or vet costs.
You don't need to have lost all your sight to benefit from a guide dog and you don't have to be officially registered as blind or partially-sighted to apply for one. See the Guide Dogs website for information about applying for a guide dog.
Guide Dogs also offer a number of other services for people with a visual impairment - even if you don't have a guide dog - such as Children and Young People's Services and mobility training.
The charity also provides the My Guide service, which aims to reduce the isolation that many people with sight loss experience, helping to rebuild their confidence and regain their independence.
Global positioning system (GPS)
GPS is a navigational aid that uses signals from satellites to tell you where you are and help you plan journeys.
GPS devices are available as stand-alone units that can be programmed using a Braille keyboard (see below), which tell you your current location and directions to where you wish to go.
If you have a smartphone, there are a number of GPS apps you can download.
If you are diagnosed with a condition that affects your vision, you have a legal obligation to inform the Driver and Vehicle Licensing Agency (DVLA). Failure to do so is a crime and can result in a fine of up to £1,000.
If you are officially registered as having a sight impairment or a severe sight impairment, the DVLA will assume your driving licence is no longer valid and you will no longer be able to drive.
Occasionally, exceptions are made in people with mild sight impairment. If you think this applies to you, then your doctor will need to fill in a DVLA medical information questionnaire (PDF, 218kb).
You are only legally allowed to drive if you can read a number plate from a distance of 20 metres (65 feet) and an eye test shows your visual acuity is at least 6/12. You are allowed to wear glasses or contact lenses when reading the plate or letter chart.
There are also standards relating to your visual field and driving. If you have a condition that may reduce your visual field, the DVLA may ask you to undertake a visual field test to demonstrate you are safe to drive.
If you are currently employed and have recently been diagnosed with a visual impairment, you should contact the Access to Work scheme.
Access to Work is a scheme run by Jobcentre Plus that provides advice and support on what adjustments and equipment may be required to enable you to do your job.
They also offer a grant to contribute towards the costs of any equipment or training that you may need, such as voice recognition software, a Braille keyboard and display unit and a printer that can convert text into Braille (Braille embossers).
Depending on the size of the company you work for, the grant can pay for 80-100% of costs, up to £10,000.
If you are currently looking for work, there are three main organisations that can provide some extra advice and support:
The RNIB, which has a useful section on their website about looking for work
Action for Blind People.
You do not have to disclose you are visually impaired when applying for a job, but it is usually recommended that you do.
If you feel you have been turned down for a job because of your disability, and you were capable of doing the job, you can make a complaint under the Equality Act 2010.
Some people with a visual impairment decide to become self-employed, often because it allows them the flexibility to work at home for hours they choose.