Abstract
Purpose :
Despite tremendous development in image display technologies, most vision exams are still performed using paper-based charts. These procedures are time consuming, labor intensive, and subject to transcription errors and “test preparation.” Display-based color vision screening would provide customized, threshold-based testing and allow integration with other vision tests in a unified platform of an automated vision tester.
Methods :
Test images designed to individually stimulate a specific cone type (L, M, and S) with minimal cross stimulation, were prepared using a commercial graphics editing software. These images were displayed on commercial displays and characterized using a colorimeter. Cone-specific contrast was computed from the cone excitations based on psychophysically derived cone sensitivities by measuring the display luminance and CIE chromaticity. Short-term drift characteristics of the tested displays were also studied by repeating measurements over an extended period.
Results :
Minimum contrast smaller than 0.25% was achieved for all (L, M, S) cone types. The contamination ratio, defined as the maximum contrast in unwanted cone types divided by the target-cone contrast, was below 0.5, demonstrating that selective, high-resolution stimulation of target cone types is possible. To achieve the minimum contrast below 0.25% for the M and S cones, spatial dithering was used. For the maximum stimuli, cone contrasts of 11% (L), 18% (M), and 99% (S) were measured. Shore-term (~hours to days) drift in color was not noticeable.
Conclusions :
Our results indicate that commercial display technologies available today are suitable for high-accuracy color vision screening. A vision tester based on these displays, combined with a software development kit to accommodate various vision tests, will provide an integrated, cost-effective platform that can address all vision screening needs, including acuity, color, ocular motility (hyper/hypo/eso/exo phoria/tropia), and stereo.
* This work is supported by the US Army Medical Research and Materiel Command under Contract No. W81XWH-17-C-0175.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.