Bex P J, Edgar G K
University of Wales, College of Cardiff.
Percept Psychophys. 1995 Nov;57(8):1187-9. doi: 10.3758/bf03208374.
Perceived brightness is nonlinearly related to luminance. Consequently, any mechanism operating on the (transformed) luminance profile of a blurred edge to detect its location should make errors, and the magnitude of these errors should increase with contrast. The perceived location of a blurred edge was measured at a range of contrasts and a range of blur space constants in a vernier alignment task. It was found that the perceived location of a blurred edge was affected by the contrast and the blur space constant of the edge. At low contrasts, the apparent location of the blurred edge was near the calculated location of the edge, assuming the linear transduction of luminance. At higher contrasts, the perceived location of a blurred edge was shifted toward the dark side of the edge, and the shift increased with contrast.
感知亮度与亮度呈非线性关系。因此，任何基于模糊边缘的（变换后的）亮度轮廓来检测其位置的机制都会产生误差，并且这些误差的大小会随着对比度的增加而增大。在游标对齐任务中，在一系列对比度和一系列模糊空间常数下测量了模糊边缘的感知位置。结果发现，模糊边缘的感知位置受边缘的对比度和模糊空间常数的影响。在低对比度下，假设亮度线性转换，模糊边缘的表观位置接近边缘的计算位置。在较高对比度下，模糊边缘的感知位置向边缘的暗侧偏移，并且该偏移随着对比度的增加而增大。
