An electronic device for generating drifting grating patterns alternating with diffuse illumination of equal mean luminosity.

Abstract

An electronic device for generating contrast patterns on a display unit is described. The apparatus permits the generation of spatially periodic bright and dark stripes of 5 different spatial frequencies, any desired orientation, and drifting velocities from 0 to 16 c/sec. The pattern is shown either over the whole screen or inside a window which can be shifted to any desired position in the surrounding of equal mean luminosity. The graftings can be alternated with diffuse illumination of equal mean luminosity at repetition frequencies between 0.5 and 16 Hz, with independent control of the duration of the contrast pattern.