MEASUREMENTS OF THE SPECTRAL MODULATION SENSITIVITY FUNCTION FOR 2 NORMAL OBSERVERS WITH CRT MONITORS

We have measured the sensitivity of the human visual system to chromat ic stimuli of single chromatic frequency, ranging from 0.2 to 8.2 cycl es/400 nm, and for eight initial phases from 0 degrees to 315 degrees. The optimal phase curves obtained for two observers show a CSF-type s hape, with minima at certain frequencies which did not appear in previ ous computational predictions. The implications of a value of the cut- off frequency of somewhat less than 8 cycles/400 nm are also discussed .