Clinical experience with the Lovibond Colour Vision Analyser. Results from the examination of normal and congenital colour-deficient subjects.

The Colour Vision Analyser was used for testing 98 persons of both sexes, aged from 10 to 70 years, and recognized as normal by means of pseudo-isochromatic plates and an anomaloscope. A drop of the saturation thresholds from yellow to green and from blue to purple was observed from the age of 40 years. The saturation thresholds from yellow to green was found lower in every age group than that from blue to purple. Congenital colour defects could be completely distinguished from normal subjects. As for the classification in types, those diagnosed as deutan by means of the anomaloscope were also diagnosed as deutan by the Analyser, however, there were, among those diagnosed as protan by the anomaloscope, some subjects who were diagnosed as deutan by the Analyser. Nearly all cases could be classified as anopia or anomaly.