Validation of a solid-state anomaloscope used to assess red-green color vision defects

Solid-state anomaloscopes whose stimuli are derived from light-emitting diodes (LEDs) are simpler and less expensive than conventional anomaloscopes. We have assessed the test-retest reliability and the validity of one solid-state anomaloscope and have obtained normative data for it. Reliability and validity were assessed by classifying 36 color-defective observers into one of five categories defined by degree of defect. When all color defectives were considered, both the validity and reliability of the solid-state anomaloscope were found to be high. The primary stimuli of the solid-state anomaloscope are less well separated in chromaticity space than are those of conventional anomaloscopes, but there is no evidence that this results in the incorrect classification of anomalous trichromats as dichromats. The solid-state anomaloscope appears to be an acceptable alternative to standard anomaloscopes for both research and screening applications.