Electric charge density distribution around simulation electrode in retinal implant

Electrical stimulation is an important issue in a visual prosthesis. In order to stimulate the nervous system economically, the electric field was analyzed by means of Poisson's equation and the finite element method. Computer simulation has revealed that the magnitude of the electric field was the highest when the stimulation site was located at the same elevation of a substrate surface. When the electrode was located at the deeper than the substrate surface, the magnitude becomes smaller. Although further analysis is necessary, our present results suggest that a computational study is useful to determine the 3D configuration of an electrode array.