The EOG signal, like the other bio-signals is corrupted by environmental interferences and biological artifacts. Current literature states that the EOG signal amplitude is merely dependent upon the position of the eyeballs relative to the conductive environment of the skull, though the signal has been found to be dependent on a few other factors in recently conducted research. The EOG signal has a frequency range between DC and 38Hz and amplitude between 10 to 100mV. The acquisition system employs Ag - AgCl surface electrodes for signal pickup which requires application of sufficient electrolyte gel to reduce the skin impedance.
The placement of electrodes is shown in Fig. This EOG signal is picked up by a bi- channel signal acquisition system consisting of the Horizontal (H) and Vertical (V) channels.
The generation of the Electrooculogram (EOG) signal can be understood by envisaging dipoles located in the eyes with the cornea having relatively positive potential with respect to the retina.
0 kommentar(er)
