Colorimetry is the formal process of evaluating the effects of colour and light on a person’s visual and perceptual symptoms when they observe pattern and text. When effective, precision coloured filters are prescribed to reduce the symptoms. With the Colorimeter, the effect of colour on visual discomfort and perceptual distortions can be efficiently measured under controlled conditions.
The equipment was developed by Arnold Wilkins while working at the Medical Research Council, to investigate the reported use of coloured overlays and lenses to reduce reading difficulties. The instrument was designed to allow a full range of colours to be sampled in a simple way, so that if there was a colour that reduced distortions, they would be able to find it.
The most effective tool is the Intuitive Colorimeter as it allows the logical and sequential investigation of colour space to find the optimal precision tint to reduce symptoms. The three parameters of colour- hue, saturation of the hue, and brightness – are adjusted independently while the eyes are colour adapted, resulting in a final colour that is extremely precise to the to the individual’s needs. Studies have shown that, for many, slight deviations from the optimal colour can cause the colour to be ineffective.
Once identified in the Colorimeter, a set of trial lenses is assembled to replicate the hue, saturation and brightness. These are trialed by the client in different light sources and for different visual tasks like reading near and in the distance, and when walking. Slight adjustments can be made however 9/10 times, the colour combination remains that which was indicated in the instrument.
A pair of lenses is then tinted, using medically designed tints, to the individual’s unique specifications. The lenses are then installed into the client’s frame of choice. While there may seem to be some consistent choice of colour when a large number of tints are compared, there is no one, two, or even 5 best colours that stand out. In fact, recent research identified that several thousand colours need to be presented to find the best solution.
The instrument is used by hundreds of community optometrist practices, hospitals and university vision clinics in the UK and around the world, with over 750,000 lenses and contacts prescribed to date. The efficacy has been demonstrated in numerous controlled trials and helps individual with many neurological conditions where cortical hyperactivation is present.