Intuitive Colorimetry (click to download lecture) is a diagnostic test used to determine the optimum tint to help alleviate or reduce symptoms of of perceptual distortions associated with Visual Stress syndrome.reported by some patients who have dyslexia, migraine or photosensitive epilepsy.This technology was developed by Professor Arnold Wilkins at the Applied Psychology Unit, Medical Research Council, Cambridge and is supported by peer reviewed research studies and controlled trials. However, this clinical area is viewed controversial by some clinicians and scientists.  

Barnard Levit Optometrists was one of the first practices in the world to use the Intuitive Colorimeter from August 1993. There is a large evidence base with much published research on this subject but nevertheless, the subject remains controversial and for this reason the practice will usually follow a step by step diagnostic process when assessing children to try and rule out any placebo effect.

The aim of carrying out Intuitive Colorimetry is to determine the optimum tint to help alleviate or reduce symptoms of visual stress The instrument independently changes the 3 parameters of colour, huesaturation and brightness while the eyes are colour adapted.


The test is designed togive a final colour specification which in some cases needs to be very precise to each individual's needs. The colour will be different for each person and the precision coming from a choice of over 100,000 colour combinations now available. In its most effective form this prescription will be delivered as Cerium Precision Tinted Lenses. The tint is selected rapidly and efficiently in an examination lasting about 20-30 minutes carried out.The optimal colour which will benefit each individual can change over time, especially with children.  It is therefore very important that the patient visits the specialised optometrist regularly for re-evaluations. The optimal colour can also be available with soft contact Lenses.


Chris aged 30 from London

“I have been using blue tinted Cerium lenses prescribed by Dr Barnard since 2005 over which time I have found them to be an absolute game changer in increasing my ability to focus on written text. The glasses dramatically reduce the glare I experience when reading which allows me to read and write effectively over long periods and the positive benefits are instantaneous. As a parent I would thoroughly recommend that parents whose children suffer from dyslexia look into whether this solution would be suitable for their children.”