Display Area of Sinusoidal Gratings and Low Spatial Frequency Channels

Abstract : The relation between stimulus size of sine gratings and low spatial frequency channels has been systematically investigated by television technique. Experimental data suggest that the human visual system contains low spatial frequency channels. Variation of the stimulus area of gratings is a significant condition for the display of the low spatial frequency channels. It was found that as the area of sine gratings increases (from 1 deg, 2 deg to 5 deg, 10 deg field), human eyes become more sensitive to the low spatial frequency, to which the position of the lowest spatial frequency channels leads. The adaptable range of low spatial frequency is extended (from 3 c/deg to 0.2 c/deg). For a 10 deg visual field, the position of the lowest spatial frequency channels stays at 0.3 c/deg. The asymmetry of the bandwidth of the low spatial frequency channels has also been observed.