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iOO Intuitive Coloured A4 Overlays

iOO Intuitive Coloured A4 Overlays

sku: MS005-AQUA

Regular price £5.99 GBP
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The Institute Of Ophthalmology produces a scientifically developed range of A4 sized coloured overlays.

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The University College London's Institute of Optometry (i.O.O.) is the oldest and largest centre for ophthalmic treatment, teaching and research in Europe.

The Institute, which is a registered charity, was founded in 1922. It is a centre of excellence within the profession of Optometry, and its main activities are optometric patient care, continuing education for Optometrists and optometric research.

They are the sole providers of Intuitive Overlays.

The ‘Intuitive Overlays’ were developed by Professor Arnold Wilkins of the Visual Perception Unit at Essex University. They have been manufactured by a specialist printer to the highest quality control standards. They are also the only overlays the design and use of which have been described in a quality optometric journal (Ophthal. Physiol. Opt., 1994).

The complete range of colours that we can perceive is described on the CIE u ‘v’ map of colour space. This resembles a triangle, with white being placed near the centre and blue, red, and green at each of the apices. The overlays have been scientifically designed to sample this colour space systematically.

There is now considerable evidence that some people benefit from the use of coloured overlays when reading.These are sheets of coloured transparent plastic that are placed on the page. Research findings suggest that, in some cases, the following conditions may be helped by the use of coloured filters:


  • Visual Stress
  • Migraine
  • Visual discomfort
  • Glare


Nine colours (plus Grey) have been chosen so that the separation between adjacent colours is similar and so that they are equidistant from white and have equivalent saturations.

The overlays can also be combined by superimposing one upon another to obtain a very large range of resultant colours.

The intuitive overlays are scientifically designed, based on human colour space. Spectral reflectance curves are approximate.

i.O.O. Intuitive Overlays are available in the following colours: -


  • Rose
  • Orange
  • Yellow 
  • Lime Green
  • Mint Green
  • Aqua
  • Blue
  • Purple
  • Pink
  • Grey



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