Fig. 19 Fusion limit as a function of stimulus pattern of a sinusoidal line (inset). A. For horizontal disparity (upper inset), fusion limit increases for stimuli with large cycles and decreases for stimuli with very small cycles. B. For vertical disparities (lower inset), the fusion limit remains much more constant. (Tyler CW: The spatial organization of binocular disparity sensitivity. Vision Res 15:583, 1975)