Tinted and coloured filters for visual discomfort

What is visual discomfort?

Visual discomfort is a term often used to describe the symptoms of eye strain or changes in the way the brain interprets the things that you see (visual-perceptual distortions), which may include headaches, difficulty focusing, blurred vision or increased sensitivity to light. Other terms used include visual stress, Meares-Irlen (or Irlen) syndrome, and scotopic sensitivity syndrome. It has been suggested that these symptoms can lead to difficulty reading.

Coloured filters, in the form of lenses or overlays, are sometimes used to treat visual discomfort associated with eye strain while reading and visual-perceptual distortions.

Do coloured filters help with visual discomfort?

There are differing views on the evidence and whether coloured filters help with the symptoms of visual discomfort. Coloured filters are not usually available on the NHS. However, the practice of using coloured filters for visual discomfort is fairly common in the UK and is often used in schools.

What we do know about coloured filters

• There is no firm evidence, but many people feel that coloured filters help reduce or get rid of the symptoms of visual discomfort
• There is little risk of harm in using coloured filters, although your colour perception may be affected
• More research on this topic is needed before we have definite evidence that coloured filters work in these situations
• An optometrist, or eye-health professional, can investigate whether there are other causes of your symptoms before considering using coloured filters
• Your optometrist, or eye-health professional, can advise you on the types of coloured filters available.

Types of coloured filters or lenses

Overlays

These are the simplest and cheapest way to test if coloured filters could help you. You can get them for a few pounds and you simply place them over the text you are reading. Some optometrists offer private tests which can help see which colour filter would benefit you the most.

Precision tinted lenses

These are lenses tinted to a precise colour that aims to help reduce visual discomfort. They will often be a different colour to the overlay.

Coloured filters and dyslexia 

It’s important to make a distinction between visual discomfort and dyslexia. The latest estimates are that visual discomfort affects around one in five people with dyslexia. But although people may be affected by both, visual discomfort and dyslexia are different conditions. There is no clear evidence that visual discomfort affects people with dyslexia more than others. Using coloured filters is not a cure for specific learning difficulties such as dyslexia, and won’t help every patient with visual discomfort, dyslexia or reading problems.

What should I do if I’m experiencing visual discomfort?

The first step is to have a sight test, to check your eyes are healthy and find out whether a pair of glasses or contact lenses would help. The next step is to follow our tips for avoiding visual discomfort. These simple steps help a lot of people.

If none of these steps work, it may be worth investigating coloured filters and lenses.

Tips for avoiding visual discomfort

• Aim for even lighting – avoid bright light sources in your field of vision. Be aware of glare from windows and consider closing curtains or blinds to reduce this
• Reduce glare from screens – adjust the screen position to reduce the glare from overhead lights
• Take regular breaks –  regularly take time away from screens or near tasks, such as reading, during your day
• Hold digital devices further away – holding phones and tablets close to your eyes means your eyes have to work harder to maintain focus. Holding these devices a little further away can help reduce eye tiredness.

Resources for your practice

If you're a practitioner, we recommend that you use this information, following a suitable examination, to reinforce advice given to the patient.

For more information on eye health, go to our For patients section.

Download our leaflet: Tinted and coloured filters for visual discomfort