Open AccessA statistical survey of colour vision
Author(s) -
R. A. Houstoun
Publication year - 1918
Publication title -
proceedings of the royal society of london. series a, containing papers of a mathematical and physical character
Language(s) - English
Resource type - Journals
eISSN - 2053-9150
pISSN - 0950-1207
DOI - 10.1098/rspa.1918.0042
Subject(s) - colour vision , trichromacy , blindness , class (philosophy) , point (geometry) , mathematics , object (grammar) , optometry , artificial intelligence , test (biology) , computer vision , color vision , computer science , medicine , geometry , paleontology , biology
It is well known that there are many people with slightly abnormal colour vision, who would not be differentiated from the normal by any of the usual tests for colour-blindness. The object of this paper was to make a statistical study of such people; such a study is of interest because it enables us to say whether normal colour vision passes gradually into colour-blindness, or whether the colour-blind form a well-defined class by themselves. This is important from the point of view of colour-vision theory. For, suppose we test the colour vision of 1000 persons, chosen entirely at random, and assign marks to it, ranging from 1 to 30, taking 1 for total colour-blindness and 30 for the most perfect colour vision it is possible to have. We could thus divide them into 30 classes. Suppose next that the number of persons in each class is plotted against the number of the class. Then we shall get a frequency curve. Such a curve might have various shapes; if it were to turn out of the shape shown in fig. 1 it would show we were dealing with two classes of persons, and it would be natural to identify the large maximum with the trichromats, and the small one with the dichromats of the Young-Helmholtz theory.