Abstract

It is known that the disparity discrimination thresholds of a feature increase rapidly as the feature is offset from the fixation plane. We confirmed this fact by measuring the thresholds for a single 10-arcmin vertical line as a function of the offset disparity from the fixation plane. Thresholds for this line were also measured as additional features were added in the field of view. The added features were never in the plane as the single test line but had nonzero disparity relative to it. Thresholds were measured as a function of the number of added features, and configurations with the same minimum relative disparity (the relative disparity of the feature closest in disparity to the test line) were compared. The results show that thresholds are significantly lower when the additional features have crossed and uncrossed disparities with respect to the test line, and that the thresholds were unaffected when the fixation plane disparity was changed by as much as 10 arcmin with respect to the test line.

© 1991 Optical Society of America