Luminance Contrast Affects the Binocular Hue Mixture in a Stereoscopic Display

In stereoscopic displays, binocular disparity generates the perception of stereo vision, as two images with parallax are presented separately to each eye and fused by the brain into a single image. Previous studies on binocular color mixture identified a ‘winner-takes-all’ rule for luminance and saturation, indicating that perceived mixtures tend to align with patches of higher luminance or saturation under low luminance contrast conditions. However, systematic exploration of binocular hue mixture, especially concerning opposite color pairs, has been lacking. This study conducted a series of color matching experiments to obtain the chromaticity of the perceived binocular hue mixture across three levels of background luminance and two levels of stimulus luminance, resulting in six distinct luminance contrast levels. The findings reveal that under low luminance contrast conditions, the binocular hue mixture adheres to the ‘winner-takes-all’ rule, with G, GB, B, and GY identified as the winning hues in their respective opposite hue groups. Additionally, the hue mixture is also biased by the sensory dominant eye for negative contrast conditions. Both the influence of the dominant eye and the winner’ hue diminish with the increasing luminance contrast, especially for negative luminance contrast.