Abstract

Insensitive regions of the retina, i.e., the optic nerve head and retinal scotomas, are generally not perceived as holes in the perceptual field. This filling-in process can also be evoked by stabilizing the retinal image. We have used the filling-in phenomenon to study the chromatic coding of the visual system. Stabilizing the boundary between a red disk and a yellow or blue annulus evoked the filling-in mechanism. When the disk was stabilized, the color of the annulus filled the disk, producing a uniform circular field whose color matched that of the annulus. We investigated the color coding in the retinal region of the disk by flashing a probe consisting of a mixture of red and green lights. The ratio of red to green that made the probe appear unique yellow was determined at several luminances. We found that the ratio depended on the color appearance of the disk rather than on the light distribution on the retina. When the disk appeared yellow or blue, the ratio was intensity invariant, but when the disk appeared reddish, the ratio was no longer intensity invariant.

© 1989 Optical Society of America