Variantor Dichromatic Spectacles


Colour vision deficiency simulation glasses.

An experience based tool that can be used to aid colour universal design, Variantor helps you to understand what the world looks like to color deficient people.

Just by wearing Variantor, allows you to very simply experience first-hand the confusing colour combinations such people see.

Guide Price: £300



This tool was developed jointly by Prof. Shigeki Nakauchi, Toyohashi University of Technology, Prof. Keizo Shinomori, Kochi University of Technology and Itoh Optical Industrial Co.,Ltd. supported by the Chubu Bureau of Economy, Trade and Industry, Japan. The work was presented at the 2006 ECVP conference in Russia.


Click here to view the poster.

We are gradually recognising the importance of colour universal design in which designers should avoid confusing colour combinations in documents for colour defectives as well as for people with normal colour vision. However, it is not always easy to avoid those confusing colours because it is difficult to describe them only by words in a manual and a special kind of software or a chart with hundreds of colour combinations are needed.

Here, we propose the functional spectral filter with which users with normal colour vision can easily find the confusing colour combinations for dichromats. Spectral transmittance of the filter was designed so that the amount of colour differences for a normal observer with the filter would be close to that for colour dichromats. The designing process of the filter was formulated as an optimisation problem of minimising the discrepancy in colour differences between people with normal vision provided with the filter and dichromats. Evaluation results with a real filter produced by vacuum deposition technology for Ishihara plates, Panel D-15 test and colour discrimination ellipse (Cambridge Colour Test) indicated that observers with normal colour vision with the filter are similar to dichromats in their colour discrimination.

[Supported by the Regional New Consortium Projects from the Ministry of Economy, Trade and Industry of Japan.]

Miyazawa K, Onouchi T, Oda H, Shinomori K, Nakauchi S, 2006, "Functional spectral filter optically simulating colour discrimination property of dichromats" Perception 35 ECVP Abstract Supplement.