‘Protanopia, deuteranopia and tritanopia are all types of dichromatism.’
‘Sometimes tritanopia occurs due to disease, because the short wavelength cone is more fragile than the other cone types.’
‘With tritanopia, the person is deficient in blue and yellow perception, although he is still sensitive to red and green.’
‘Only about 0.005% of the population (male and female) are totally colour blind, and 0.003% have tritanopia, or blue-blindness.’
‘A useful tool for reviewing information about color-blindness and checking legibility of images for color-blind users is Vischeck, an on-line tool that simulates the way an image or a website might appear to a user who has deuteranopia, protanopia, or tritanopia.’
Origin
Early 20th century from trito-‘third’ (referring to blue as the third colour in the spectrum) + an-‘without’ + -opia.
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