deuteranopia

   Also known as deutan colour deficiency, deutan colour blindness, *Daltonism, and green-red blindness. The term deuteranopia comes from the Greek words deuteros (second), an (not) and opsis (seeing). It translates roughly to 'not being able to see the second of the primary colours, (i.e. green)'. The term deuteranopia was introduced in or shortly before 1837 by the German physicist August L.F.W. Seebeck (1805-1849) to denote the green-red type of * colour vision deficiency. Deuteranopia can be divided into dichromatic deuteranopia and anomalous trichromatic deuteranopia. In dichromatic deuteranopia the green-red colour blindness is absolute, due to the absence of the medium-wavelength cones or M-cones. In anomalous trichromatic deuter-anopia the M-cones are present, but malfunctioning. As a consequence, there is a diminished ability rather than an absolute inability to distinguish between greens and reds. The latter condition is also referred to as deutanomaly. Deuteranopia is the most common form of the colour vision deficiencies. As it is an X-linked autosomal condition, it affects 6% of all men, but very few women. The term deuteranopia is used in opposition to the terms *protanopia and * tritanopia.

   References

   Hsia, Y., Graham, C.H. (1965). Color blindness. In: Vision and visual perception.Editedby

   Graham, C.H. New York, NY: John Wiley & Sons.

   McIntyre, D. (2002). Colour blindness. Causesand effects. Chester: Dalton Publishing. Seebeck, A. (1837). Ueber den bei manchen Personen vorkommenden Mangel an Farbensinn. Annalen der Physik und Chemie, 42, 177-233.