AIM: To accurately measure the implicit time and amplitude of a-, b-wave from flash electroretinogram(ERG)through filtering technology, eliminate oscillatory potentials interference.

METHODS: Full-field ERGs were recorded in 30 eyes of 15 physical check-ups, measured the implicit time and amplitude of a-, b-wave, when the passband was set at 0.6～300Hz and 0.6～70Hz, and correlation was performed among those results by paired t-test.

RESULTS: When the passband was set at 0.6～70Hz, a-, b-wave had a single peak, compared with the passband was set at 0.6～300Hz, the implicit time of a-, b-wave was prolonged, amplitude was decreased(P<0.01).

CONCLUSION: A passband of 0.6～70Hz was the best choice to obtain smooth a- and b-waves from the original ERG, It could accurately measure the implicit time and amplitude of a-, b-wave.