Linklater & Warren
Chislehurst -
020 8295 5131
Linklaters Optometrists
Bexleyheath -
020 8303 4014
Leslie Warren Opticians
Sevenoaks -
01732 452 135

Colorimetry: tints for visual stress and dyslexia



Specialist assessment for the symptoms of visual stress

colorimetry testing

Several of our Optometrists have a specialist interest in the assessment and treatment of visual stress for both children and adults with reading difficulties.  Visual stress (or Meares-Irlen Syndrome) is a condition referring to reading difficulties, light sensitivity, strain and headaches from exposure to disturbing visual patterns such as text on a page.  Visual stress is thought to be caused by an over-sensitivity of the brain when viewing certain patterns (‘visually induced cortical hyperexcitability’) and can be responsible for rapid fatigue when reading and can affect both adults and children.

The following descriptions and symptoms are often given by individuals with visual stress to describe the discomfort they experience from everyday tasks such as reading:

  • Movement of print.
  • Blurring of print.
  • Doubling or fading of letters.
  • Illusions of colour within the text.
  • Patterns appearing (sometimes described as “worms” or “rivers”).
  • Glare and the page appearing “too bright”.
  • Skipping words or lines.
  • Using finger following.
  • Eyestrain.
  • Rapid fatigue and eye rubbing.

The symptoms of visual stress can be successfully alleviated with precision colour-tinted spectacle lenses and coloured overlays.  The colour needed to alleviate the symptoms is individual-specific and are determined by our accredited Optometrists using the Intuitive Colorimeter.



Relief from Visual Stress - Coloured Overlay Assessment and Colorimetry

Step One – A Thorough Eye Examination

In the first instance we recommend that patients with visual stress or dyslexia have a thorough Eye Examination to rule out an alternative cause of the symptoms.   Specific emphasis will be given to assessing how well the eyes work together.  In some cases a need for spectacles or the prescribing of eye exercises is enough to alleviate the visual discomfort.

Step Two – Coloured Overlay Assesment

Coloured plastic sheets are presented over text to assess for a reduction in the symptoms of visual stress.  Through a process of elimination the best colour is determined.  Reading speed and accuracy is measured using the Wilkin’s Rate of Reading test both with and without the chosen overlay (or combination of overlays).  If there is a significant improvement in reading speed and accuracy a coloured overlay is recommended.  At this point the chosen overlay is taken away for use in home and school. In the case of children we ask parents and teachers to monitor the child’s reading speed, comprehension and how frequently the overlay is used without being reminded. In most instances the overlay assessment and subsequent overlay home trial is used to ascertain whether an individual will benefit from precision colour-tinted spectacle lenses.

Step Three – Colorimetry and the prescribing of tinted spectacles

Following a positive result from the overlay assessment and home trial we recommend a Colorimetry Assessment, following which tinted spectacles can be prescribed.  The Intuitive Colorimeter is a specialist instrument that allows text to be viewed under different coloured light sources.  The hue (colour), saturation (density of colour) and brightness are altered in tiny increments until the precise shade is found that best minimises or eliminates the patient’s symptoms.  Tinted spectacles allow the colour to be accurately specified to the individual's needs and so are more effective than coloured overlays.  Tinted spectacles also more convenient and can be used to reduce visual stress from other sources such as white boards and computer screens.
For more information or to book an appointment for an Eye Examination with Coloured Overlay Assessment or Colorimetry Appointment please contact us and speak to a member of our team.



Visual Stress and Dyslexia

Although problems with sight do not cause dyslexia, visual stress occurs much more often in those with dyslexia and can contribute to difficulties experienced with reading.  We recommend all children with dyslexia have an eye examination to rule out a visual component to their reading difficulties.



Visual Stress, Migraine and other conditions

There are many triggers for migraine such as stress, certain foods or hormonal factors.  For some individuals everyday patterns such as text can trigger a migraine without necessarily causing difficulties reading.  For these people the use of precision colour-tinted lenses can help reduce the frequency of these visually precipitated attacks.  There is also research that suggests these coloured lenses can help those who suffer with photosensitive epilepsy, autism, ADHD and multiple sclerosis.



What is Colorimetry?



Society for Coloured Lens Providers

Our accredited Optometrists are members of the Society of Coloured Lens Prescribers and are experts in providing eye care and treatment for those with visual stress and dyslexia.



For more information visit: