Brightness for different surround conditions: The effect of transient glare

摘要

We measured the effect of a transient glare source on the perceived brightness of a standard luminance (L-STD) patch (0.5 cd/m(2)) as a function of the surround luminance (L-S). In the experiment, both increment and decrement stimuli were dependent on the value of the L-S (0.01, 0.2, 0.4, 0.6, 0.8,1.0,1.5, or 2.0 cd/m(2)). We adopted a magnitude comparison paradigm using constant stimuli to determine the test matching luminance (L-M). When L-S was lower than the luminance of the patch, which corresponds to increments, LM was lower than L-STD, and this effect was highest for the lowest L-S. There was a small but noticeable cusp as increments shifted to decrements. As L-S increased further (i.e., as the decrement grew), L-M flattened out below L-STD. The overall pattern of results could be interpreted in terms of the concept of contrast brightness, with consideration of the intrinsic differences in brightness evaluations between decrements and increments.