Coloured filters will not give red-green colour deficient observers normal colour vision


  • Elise W. Dees Høgskolen i Buskerud, Avdeling for optometri og synsvitenskap, Frogs vei 41, 3611 Kongsberg, Norge
  • Rigmor C. Baraas



Fargesyn, fargesynssvakheter, fargede filtre, ChromaGen, fargesynstester


There have been several reports over the last 200 years on how coloured filters might improve red-green colour deficient observers’ ability to discriminate colours. Many red-green colour deficient observers have unrealistic expectations with regards to the effect of such filters after reading some of these accounts. This case report presents the accounts of three young men with red-green colour-deficiency who share an ambition to study for a profession that require normal trichromatic colour vision: shipmaster, chief officer and aircraft technician. ChromaGen filters were fitted monocularly and the three men were tested with a range of colour-vision tests. All three were classified as having a deutan colour-vision deficiency. The results from colour-vision testing with and without filters are discussed in relation to functional improvement and also in relation to ethical issues.


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How to Cite

Dees, E. W., & Baraas, R. C. (2011). Coloured filters will not give red-green colour deficient observers normal colour vision. Scandinavian Journal of Optometry and Visual Science, 4(2), 6–13.



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