Rotating stripes and the impulse response of the eye: II. Stroboscopic illumination

The visual effect perceived when a rotating sinusoidally striped pattern is viewed under stroboscopic illumination consists of a band of relatively high contrast repeated at intervals across the pattern. On the basis of a previous linear model (Wolf, J. E., 1987, Spatial Vision, Vol. 2, pp. 199-211), the contrast distribution is shown to correspond to the Fourier transform of the temporally sampled impulse response of the eye, the stroboscopic illumination providing such a sampling. The analysis uses the analogy of these perceived contrast effects with the amplitude distribution in a Fraunhofer diffraction pattern established earlier (Wolf, 1987), and in this situation the stroboscopic illumination temporally samples the impulse response of the eye in the same way that the slits sample the 'aperture function' in a diffraction grating.