Acquisition and processing of ERG signals

This paper proposes a low cost acquisition and processing system for electrical biopotentials that can be obtained of the cornea (electroretinography, ERG), of the brain (electroencephalography, EEG) and of the heart (electrocardiography, ECG) to mention ones. This system is built with discrete circuits and has a minimum level of amplification of 60 dB and a maximum of 100 dB alike has a pass band Butterworth filter of 4^th grade with a bandwidth of 0.16 to 300 Hz. For the signal´s acquisition we used the sound card of the PC and through one program developed in MatLab, several techniques of filtered are applied in order to improve the signal and finally show it in a graph. This work shows biological signals acquired from the retina of a 24 years old man.