抄録
It is well known that perceived color is not determined by the photometric values alone but instead depends on the surround pattern and the adaptation condition of the eye. It is important that we know how color in complex patterns appears because the scenes we usually see are complicated. In this study, we estimated the surround effect for the appearance of achromatic colors with two and four surrounds using a new matching method that gives us the equivalent luminance of the simple uniform surround. The magnitude of the surround effects of plural stimuli can be qualitatively described by the equivalent luminance. The results show that the average luminance of surround stimuli cannot explain the total surround effects of plural stimuli, and that the spatial additivity of surround effects depends on the stimulus conditions. In addition, some characteristics of the surround effects differ between conditions with a gap and conditions without a gap. The spatial additivity of the surround effects in the present study can be expressed by the summation of the luminance values of each surround weighted by a function of the luminance of the central patch.
