Abstract
In the conventional neon-color pattern such as Ehrenstein one, color spreading from the inner grey cross, locating between four black branches and the white background, allows us to perceive a circular transparent veil overlapped on a black cross. The color spreading phenomenon persists as long as the luminance of the inner cross is intermediate between those of the background and the branches, called it Metelli's law (Nakayama et al, 1990). And it is known that the luminance relationship (LR) around each T-junction within the neon pattern uniquely determines whether one could see color spreading or not. To test its generality of such luminance rule, a new pattern is designed: a white cross occludes a grey disk with the black background. Notice that although the LR around each T-junction in the new case is identical to the above case, the neon-color phenomenon is absent. However, the grey disk is seen in front of the white cross as the luminance of the grey areas is increased and almost reached to that of the white cross, accompanying with the neon-color effect spreading into the white cross from four grey areas. Thus, the occluded disk becomes a transparent disk hanging over the cross, i.e. the figure-ground inversion. In addition it is found that this effect can be observed within other T-junction figures that contain occluded grey areas, and its strength depends on the width of the occluder, following Petter's rule. Results suggest that neon-color spreading is perceived within new patterns having occluded greys as well as the conventional neon-color displays.
Meeting abstract presented at VSS 2014