Abstract

When measured with small, sharp-edged targets, sinusoidal-grating thresholds are biased by two types of artifacts related to Weber’s and Ricco’s laws. These artifacts depend on both the nominal frequency of the grating and the phase at its edge: the effect of truncating a low-frequency grating at a given phase is just opposite from the effect of truncating a high-frequency grating at the same phase. These edge effects are predicted by spatial-frequency analyses of the targets, and confirmed by appropriate modulation-threshold measurements, with both rectilinear and circular gratings.

© 1970 Optical Society of America

Adaptation to Pattern Spatial Frequency: Effects on Visual Movement Sensitivity in Humans*†

Allan Pantle
J. Opt. Soc. Am. 60(8) 1120-1124 (1970)

Visual Masking by Low-Frequency Sinusoidally Modulated Light

G. M. SHICKMAN
J. Opt. Soc. Am. 60(1) 107-117 (1970)

Wavelength Discrimination Measured with Square-Wave Gratings*

R. Hilz and C. R. Cavonius
J. Opt. Soc. Am. 60(2) 273-277 (1970)

Effects of average-luminance surrounds on the visibility of sine-wave gratings

John J. McCann and John A. Hall
J. Opt. Soc. Am. 70(2) 212-219 (1980)

Spatial-Frequency Discrimination in Human Vision

Fergus W. Campbell, Jacob Nachmias, and John Jukes
J. Opt. Soc. Am. 60(4) 555-559 (1970)