Abstract

It is known that in Speillman's illusion, light regions are observed at the intersection of dark bars on a light background and dark regions are noted at the intersection of the light bars on a dark background. The illusion may disappear depending on the observation distance. The optimal visual angle of the distance is 6 and 18 min of arc. This indicates the excitatory region of human receptive fields. Although the process may not be the same as the illusion described above, the present research systematically investigates the perception of the computer-generated geometric figures consisting of fine black grids surrounded by high-frequency colored grids. Six different colors of surrounding grids figures with five different densities of grid were tested. The subjects perceived a black grid figure as various reflecting colors which were complementary to the surrounding grid colors. The perceived colors matched by the subjects and stimulus colors are further analyzed by a photodensitometer.

© 1987 Optical Society of America