Abstract: A software package which could give out three stimuli──Dynamic random dot stereograms (DRDS), Light-dark checkerboard and Random dot background stimulus, was developed. Using the three stimuli respectively, cortical visual evoked potentials (VEPs)in 34 normal subjects were recorded. The results showed that: (1) In the VEP elicited by DRDS, the latency of N1 peak was 265 ± 25ms and the power of the first harmonic was 63.2±18.9 percent of the total power; (2) In the VEP elicited by Light-dark checkerboard, the latency of N1 peak was 190 ± 22ms and the power of the first harmonic was 39.2 ± 19.6 percent of the total power; (3) The VEP elicited by random dot background consisted of some disorderly small waves. The results showed that there were some characteristics in the distribution of harmonics power besides latency of the VEP elicited by DRDS. The above characteristics are helpful in the objective evaluation of stereopsis.

Key words: Stereopsis, Dynamic random dot stereograms, Visual evoked potentials