Fig. 1.

A, stimulus spatial configuration; B, chromaticities. A, a 12°(inner diameter) − 16°(outer diameter) annulus was surrounded by an inner circular field and an outer rectangular field. A “+” (0.14°) served as fixation, which was located in the center of the inner field. The test patch was a section of the annulus with a central angle of 20°. B, stimulus chromaticities. The test annulus had an s chromaticity of 0.6, 0.8, 1.0, 1.2, or 1.6 and l chromaticity of 0.625, 0.665, or 0.705. The chromaticities of the adapting fields were “yellow”–“green” (l, s = 0.625, 0.6), “green” (l, s = 0.625, 1.0), “blue” (l, s = 0.625, 1.6), “yellow” (l, s = 0.665, 0.6), “white” (l, s = 0.665, 1.0), “purple” (l, s = 0.665, 1.6), “orange” (l, s = 0.705, 0.6), “red” (l, s = 0.705, 1.0), and “pink” (l, s = 0.705, 1.6).