RESPONSE OF HUMAN EYE TO SPATIALLY SINUSOIDAL GRATINGS AT VARIOUS EXPOSURE DURATIONS

The shapes of human spatial contrast sensitivity functions for sinusoidal luminance patterns were strongly dependent upon exposure duration, exhibiting a linear low frequency decline of threshold for long exposures and no decline for brief exposures. This result confirmed earlier work with square-wave patterns but conflicted with some sine-wave experiments. Narrow-band spatial channels at low spatial frequencies may be approximately equal in sensitivity when temporal properties of the mechanisms are taken into account. The results are related to models for the Craik-O''Brien-Cornsweet phenomenon.