Diagnosis and genetics of defective colour vision / by H. Kalmus.

  • Hans Kalmus
Date:
[1965]
Catalogue details

Licence: Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)

Credit: Diagnosis and genetics of defective colour vision / by H. Kalmus. Source: Wellcome Collection.

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    essentials of colour theory 9 yellow (see p. 56). Accordingly the confusion zones of deuteranopes do not radiate but are parallel to the red-green axis (Fig. 6). Tritanopes which lack the blue sensation have again radiating confusion zones (Fig. 7), in this case originating from the blue corner. RED ( 65^) Fig. 6. Confusion zones for a deuteranope showing the iso-colour zones (after Wright, 1946). Colours as in Fig. 5. The existence of the confusion colours as represented by the zones in these charts are the basis for most tests of defective colour vision with the exception of the anomaloscope. The trichromatic theory postulates that in addition to the rods, which operate at low light intensities (scotopic vision, p. 20) and may at medium levels of illumination also be imphcated in blue perception (p. 20), three kinds of cones operate at higher light intensities (photopic vision) the pigments of which have different maximum sensitivities in the spectrum and also different colour absorption (p. 28). It should be noted that the trichromatic theory does not require the existence of separate yellow receptors. The sensation y^Uow results from the simultaneous stimulation of red
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