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EXAMINATION OF COLOUR VISION BY USE OF INDUCED CONTRAST COLOURS
Author(s) -
HANSEN EGILL
Publication year - 1976
Publication title -
acta ophthalmologica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.534
H-Index - 87
eISSN - 1755-3768
pISSN - 1755-375X
DOI - 10.1111/j.1755-3768.1976.tb01290.x
Subject(s) - contrast (vision) , colour vision , chart , hue , lightness , selection (genetic algorithm) , optometry , brightness , artificial intelligence , mathematics , computer science , statistics , pattern recognition (psychology) , computer vision , medicine , optics , physics
The ability to induce contrast colours is evident in normal persons by the tissue paper contrast principle. However, tests of good quality are not easily available. The design of a new series of charts follows two principles: 1) Selection of background hues in accordance with the maximally desaturated regions of the spectrum as seen by the colour defectives. 2) Exact adjustment of the neutral test field (constituted by the chart figures) in order to eliminate any false clue due to brightness contrasts. By introducing chart figures of alternative grey values appropriate tests can be attained for each type of colour vision defect 37 persons with congenital colour defects and 15 persons with acquired defects were examined. The charts, according to the criteria for selection, proved to be selective in their screening efficiency