Abstract

In certain conditions, the isometric projection of a rigidly rotating eight-vertex polygon appears to deform.¹ Sparrow and Stine² suggested that the difference in rotational phase between vertices controls the degree to which a change of shape is perceived during rotation. The degree to which the rotating polygon appeared to deform was measured by asking subjects to adjust the retinal disparity required to just cancel deformation. Given that a rigidly rotating polygon appears rigid when viewed directly (as opposed to viewing an isometric projection of the polygon), our disparity threshold represents the depth information required to resolve ambiguities in the perceived shape of the figure.

© 1987 Optical Society of America