2017 Volume 38 Issue 2 Pages 22-29
The purpose of this study was to clarify the characteristics of color discrimination in mesopic vision by analyzing error scores of the Farnsworth-Munsell 100-hue test under several retinal illuminance conditions, which were at the mesopic luminance level. The retinal illuminance conditions were 0.07, 0.35, 0.71, 3.53, and 7.07 td. The results were as follows.: 1) Under the retinal illuminance conditions of 0.07∼0.35 td, the characteristics of color discrimination in scotopic vision became dominant. 2) When retinal illuminance was kept relatively high in mesopic vision, color discrimination along the yellow-blue confusion axis was reduced. 3) Color discrimination along the rod confusion axis markedly reduced correspondence with retinal illuminance toward scotopic luminance levels. These results suggest that rod signals directly affect S-cone mediated chromatic discrimination, and that scotopic brightness cues are equal to weak S-cone-mediated hue signals.
